US20030003690A1 - Semiconductor device separation using a patterned laser projection - Google Patents
Semiconductor device separation using a patterned laser projection Download PDFInfo
- Publication number
- US20030003690A1 US20030003690A1 US10/146,267 US14626702A US2003003690A1 US 20030003690 A1 US20030003690 A1 US 20030003690A1 US 14626702 A US14626702 A US 14626702A US 2003003690 A1 US2003003690 A1 US 2003003690A1
- Authority
- US
- United States
- Prior art keywords
- semiconductor wafer
- wafer
- laser projection
- device layer
- patterned laser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000004065 semiconductor Substances 0.000 title claims abstract description 62
- 238000000926 separation method Methods 0.000 title abstract description 23
- 235000012431 wafers Nutrition 0.000 claims abstract description 128
- 238000000034 method Methods 0.000 claims abstract description 56
- 238000005520 cutting process Methods 0.000 claims abstract description 35
- 238000000608 laser ablation Methods 0.000 claims abstract description 7
- 230000003287 optical effect Effects 0.000 claims abstract description 6
- 239000000758 substrate Substances 0.000 claims description 33
- 229910052594 sapphire Inorganic materials 0.000 claims description 21
- 239000010980 sapphire Substances 0.000 claims description 21
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 13
- 238000004140 cleaning Methods 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 8
- 150000004767 nitrides Chemical class 0.000 claims description 6
- 238000007664 blowing Methods 0.000 claims 4
- 238000000151 deposition Methods 0.000 claims 1
- 238000012545 processing Methods 0.000 abstract description 6
- 239000000853 adhesive Substances 0.000 abstract description 5
- 230000001070 adhesive effect Effects 0.000 abstract description 5
- 238000011109 contamination Methods 0.000 abstract description 5
- 239000011241 protective layer Substances 0.000 abstract description 4
- 239000000463 material Substances 0.000 description 15
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 13
- 229910002601 GaN Inorganic materials 0.000 description 11
- 239000010432 diamond Substances 0.000 description 9
- 239000010410 layer Substances 0.000 description 9
- 229910003460 diamond Inorganic materials 0.000 description 7
- 238000002679 ablation Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000008901 benefit Effects 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- 235000002595 Solanum tuberosum Nutrition 0.000 description 1
- 244000061456 Solanum tuberosum Species 0.000 description 1
- 239000002390 adhesive tape Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical group [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 229910052743 krypton Inorganic materials 0.000 description 1
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 description 1
- 238000003698 laser cutting Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 229910052754 neon Inorganic materials 0.000 description 1
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 1
- 230000005693 optoelectronics Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 229920002120 photoresistant polymer Polymers 0.000 description 1
- 239000011214 refractory ceramic Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
- B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
- B23K26/073—Shaping the laser spot
- B23K26/0738—Shaping the laser spot into a linear shape
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
- B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
- B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
- B23K26/066—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms by using masks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
- B23K26/362—Laser etching
- B23K26/364—Laser etching for making a groove or trench, e.g. for scribing a break initiation groove
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
- B23K26/40—Removing material taking account of the properties of the material involved
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L21/6835—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L21/6836—Wafer tapes, e.g. grinding or dicing support tapes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/77—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate
- H01L21/78—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/36—Electric or electronic devices
- B23K2101/40—Semiconductor devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/50—Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/304—Mechanical treatment, e.g. grinding, polishing, cutting
- H01L21/3043—Making grooves, e.g. cutting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2221/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof covered by H01L21/00
- H01L2221/67—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere
- H01L2221/683—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L2221/68304—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L2221/68327—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support used during dicing or grinding
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2221/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof covered by H01L21/00
- H01L2221/67—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere
- H01L2221/683—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L2221/68304—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support
- H01L2221/6834—Apparatus for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components; Apparatus not specifically provided for elsewhere for supporting or gripping using temporarily an auxiliary support used to protect an active side of a device or wafer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/005—Processes
- H01L33/0095—Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S438/00—Semiconductor device manufacturing: process
- Y10S438/94—Laser ablative material removal
Definitions
- This invention relates to the field of semiconductor fabrication, and more particularly to semiconductor device separation.
- Sapphire wafers are an important semiconductor substrate. They are especially important for the development of gallium nitride based materials technology, which is used in blue spectrum light emitting diodes (LEDs). The production of high brightness LEDs in the blue spectrum is a relatively recent optoelectronics technology. The demand for nitride based LEDs, such as bright blue, bright green and other color LEDs, currently exceeds the industry's capability to supply them. Sapphire based device separation, however, remains a significant obstacle to efficient fabrication. Current separation techniques waste valuable wafer surface area, involve costly consumables, and have long process times.
- Semiconductor fabrication processes involve fabricating several thousand individual devices, or die, on one wafer. After processing and testing, the wafer may be thinned and the die must be separated from the wafer. Separation has been traditionally accomplished using either a dicing saw or a scribe-and-break process, both of which rely on diamond chips to cut the material. These two processes have been very effective on silicon and III-V substrates, because the material is much softer than diamond. However, sapphire's crystal structure, crystal orientation, inherent hardness, and material strength inhibit these methods from working well.
- the scribe-and-break separation process also relies on a sharp diamond edge or facet.
- the scribe tip has a diamond head which is quickly dulled by the sapphire. This requires frequent and costly tip replacement. Due to these factors, a sapphire dicing process will produce too low a yield. Moreover, both the sawing and diamond scribing process become very complex due to diamond wear.
- the present invention is a method for efficient and inexpensive separation of semiconductor wafers by laser ablation.
- the method uses a laser to ablate material from the substrate, resulting in a separated wafer.
- Laser separation is advantageous because it permits processing of any sapphire based product, such as blue LEDs, inexpensively and quickly.
- the separation methods are applicable to gallium arsenide (GaAs) and to other semiconductors with the same potential benefits of high throughputs, narrow kerfs and no cutting tips to wear.
- the method of the present invention separates semiconductor wafers into a plurality of devices via laser ablation.
- a laser light emission is generated and sent through optical elements and masks to obtain a patterned laser projection.
- the patterned laser projection is then directed toward a given surface of a semiconductor wafer such that the patterned laser projection is substantially perpendicular to the given surface.
- the patterned laser projection is applied for a specified time at a specified power to obtain at least a partial cut through the semiconductor wafer. If the wafers are not fully cut using the laser, a mechanical method is then applied to complete the separation and create the die.
- the pattern of the laser projection can be selected in view of the type of semiconductor wafer.
- the patterned laser projection of the present invention can be one long, narrow line that cuts several millimeters with one pulse or several smaller lines that cut several rows simultaneously with one pulse.
- a protective layer is applied to the cutting surface to prevent cutting process effluent from contaminating the devices.
- the method of the present invention results in a kerf in the order of 10 ⁇ m wide if cut from a front surface and less than 10 ⁇ m if cut from a back or substrate surface. Consequently, the present invention reduces wastage of wafer space and permits more devices to be placed on the wafer. The above factors make the present invention an efficient, low maintenance and high production method for separating semiconductor wafers. Such a method is a significant step toward meeting the demand for sapphire based devices.
- a cleaning system is used during ablation to draw up particles and smoke to improve the ablation process and reduce post ablation cleaning of the material.
- a reflector is applied to a wafer surface opposite the laser emission to reflect laser light back onto the wafer thereby making more efficient use of the laser emission.
- FIG. 1 is an exemplary embodiment of a laser-based semiconductor separation system in accordance with the present invention
- FIG. 2 shows a more detailed view of a projection delivery system outputting a patterned light projection onto a surface of a semiconductor wafer in accordance with the present invention
- FIG. 3 shows a cross-sectional view of a semiconductor wafer in accordance with the present invention
- FIG. 4 graphically shows the steps involved in the method of the present invention
- FIG. 5 shows one laser cut die in accordance with the present invention
- FIG. 6 shows a plurality of laser cut die in accordance with the present invention
- FIG. 7 shows a laser cut in GaN in accordance with the present invention
- FIG. 8 shows a scanning electron microscope photo of a laser cut die in accordance with the present invention
- FIG. 9 shows a more detailed view of an alternate projection delivery system outputting a patterned light projection onto a surface of a semiconductor wafer having a surface cleaning system in accordance with the present invention.
- FIG. 10 shows an alternate cross-sectional view of a semiconductor wafer in accordance with the present invention.
- the method of the present invention separates a semiconductor wafer into several thousand devices or die by laser ablation.
- Semiconductor wafers are initially pre-processed to create multiple devices, such as blue LEDs, on the wafers.
- the wafers are then mounted with tape coated with a generally high level adhesive.
- the mounted wafer is then placed on a vacuum chuck (which is itself positioned on a computer controlled positioning table) to hold it in place during the cutting process.
- the cutting surface is then covered with a protective layer to prevent contamination from the effluent resulting from the actual cutting process.
- a laser light emission is generated and passed through optical elements and masks to create a pattern, such as a line or multiple lines.
- the patterned laser projection is directed at the wafer at a substantially normal angle and applied to the wafer until at least a partial cut is achieved through it.
- a mechanical separation process completes the separation when only a partial cut is achieved by the patterned laser projection.
- the die are then transferred to a grip ring for further processing.
- System 100 includes a laser 110 coupled to a computer control 120 and a projection delivery system 130 .
- Laser 110 is any laser that has the necessary parameters, for example, power, wavelength and frequency, to cut semiconductor wafers, such as but not limited to KrF lasers, Nd:YAG lasers, and other lasers.
- projection delivery system 130 uses optical elements and masks to shape the laser light emission into a pattern 200 that will optimize the cutting process on semiconductor wafer 105 .
- the optimal pattern may be either one long, narrow line that will cut several millimeters of the surface up to 100 ⁇ m deep with each pulse, or several smaller lines that will cut several rows simultaneously with each pulse. Other patterns, such as a grid pattern can also be used.
- the optimal configuration depends on the type of semiconductor wafer being separated.
- semiconductor wafer 105 is situated on a vacuum chuck 140 to hold semiconductor wafer 105 in place during the cutting process. Moreover, as explained below, vacuum chuck 105 flattens the shape of semiconductor wafer 105 during the cutting process. Vacuum chuck 140 is situated on a xyz theta positioning table 150 .
- Computer control 120 controls the movement of xyz theta positioning table 150 with respect to patterned light projection 155 so as to place the cuts in the correct areas. As the name of the table implies, computer control 120 moves semiconductor wafer 105 in the x, y and z axes and rotates it a given ⁇ . This, along with video monitor 160 provides accurate control and placement of where patterned light projection 155 will cut semiconductor wafer 105 .
- FIG. 3 shows a cross-sectional view of a processed semiconductor wafer 300
- FIG. 4 which illustrates graphically some of the steps in the method of the present invention.
- the epitaxial growth material can be, for example, any semiconductor material such as any of the III-V materials listed in the periodic chart of elements.
- the substrate material can be, for example, any of the III-V materials, refractory ceramics and any orientations of any of the listed substrate materials.
- a semiconductor wafer 300 has a front surface 305 , which is also referred to as the epi or epitaxial surface, and a back surface 310 , which is also referred to as the substrate surface.
- GaN layer 315 Prior to cutting, GaN layer 315 will have been etched and coated with three metal patterns 320 and a dielectric 350 .
- Sapphire substrate 340 may be thinned from 0.017′′ to 0.004′′. The processing creates approximately 11000 devices on a 2′′ diameter wafer. Due to lattice mismatch in the GaN/sapphire structure, the resulting stress in the structure causes the wafer to “bow”, such that it resembles a potato chip.
- wafer mounting The bow in the wafer is flattened by a process termed wafer mounting.
- the wafer mounting process is also required to keep the 11000 individual devices in order.
- wafer 300 is mounted on 0.003′′ to 0.005′′ thick tape 330 coated with a generally high tack adhesive.
- the mounting process is outlined below:
- the vacuum chuck can either be porous ceramic or contain concentric metal rings. The latter may require a backing so the ring pattern is not pressed into the tape.
- the parameters of the patterned laser projection are set in one embodiment of the method to achieve only a partial cut through the device.
- a mechanical breaking process is used to complete the separation. If a full or total cut through the wafer is desired, another layer must adhered on to the bottom of the mounting tape. This layer, for example, could be an epoxy or double sided tape.
- the user Prior to the wafer mounting process, however, the user must decide which surface of the wafer to cut on. Whether to cut on the front surface or the back may depend upon the cut width or kerf that is produced for the particular type of wafer being cut. To minimize wafer wastage, the kerf value should be on the order of 10 ⁇ m wide. For example, front and back surface cuts should have kerf values of less than 100 ⁇ m. For the illustrative GaN/sapphire structure, the kerf value is about 20 ⁇ m when cutting from the front surface and less than 10 ⁇ m when cutting from the back surface. However, there are additional considerations that must be accounted for before deciding on which surface to cut on.
- a protective layer must be placed on it.
- the cutting process coats the wafer's surface with effluent, which is unacceptable.
- the wafer's surface is protected with either photoresist or polyimide during a laser separation process, and the coating is removed with a solvent after the process. This is not possible in the present case because the solvent may damage mounting tape 330 .
- the contamination problem is overcome by covering the cutting surface with a generally lower tack mounting tape 345 . This provides excellent protection from effluent. Two pieces of tape were used for each wafer-one for X direction cutting and one for Y direction cutting.
- Laser 110 for example, a KrF laser operating at 248 nm or a Nd:YAG operating at 1064 nm, is activated to generate laser light emission operable to cut the semiconductor wafer.
- the laser light emissions are fed through projection delivery system 130 to produce a pattern.
- the patterned light projection is then directed toward a selected cutting surface of the wafer so that it is substantially normal to the cutting surface.
- the parameters of the laser are set to achieve the required cut without inducing cracking and chipping.
- Studies using several types of laser sources have indicated that multiple shallow cuts, for example, cut depths of one mil to three mils for a 13 mil thick wafer, are required to separate sapphire based substrates without cracking.
- deep cuts for example, a 6 mil deep cut, caused cracks in the wafer.
- Cut depths of 45 ⁇ m leave very little effluent on the surface. As stated above, this is a very important consideration in terms of contamination of the separated devices.
- the parameters are also set to achieve the desired partial or full cut through the wafer. As shown in FIG. 3, cuts 360 are made through oxide layers 360 .
- FIG. 4 a graphical representation 400 of how a wafer is cut is shown.
- tape 420 is placed on the cutting surface of wafer 410 (step 2 ).
- Taped wafer 430 is cut in the X direction (step 3 ) and the excess tape is removed (step 4 ).
- X cut wafer 440 is again covered with tape 420 (step 5 ) and is now cut in the Y direction (step 6 ).
- the excess tape is removed, leaving at least a partially cut wafer 450 (step 7 ).
- FIGS. 5 - 6 the above method separates the entire wafer into square die.
- the cuts are on 400 ⁇ m centers, in the X and Y directions.
- the cut depths are roughly 85 ⁇ m.
- the remaining 15 ⁇ m is mechanically broken using conventional techniques.
- a single laser cut die 500 is shown in FIG. 5 and a plurality of die 600 are shown in FIG. 6.
- the actual die size is 372 ⁇ m with a kerf width of 28 ⁇ m.
- FIG. 7 is an example of a laser cut in GaN that has a kerf width of 20 ⁇ m
- FIG. 8 shows a scanning electron microscope photo of characteristic features of a laser cut surface.
- the wax paper is removed and the cut quality is inspected.
- the next steps depend on the wafer's orientation during cutting. If the wafer was mounted with the GaN surface on the mounting tape and cut from the back surface, the individual die must be remounted on tape with the GaN surface facing up. That is done using the following process:
- the wafer and the tape on which it was cut is transferred to a grip ring. If the mounting tape was damaged, then two tape transfers are necessary. The first would place the die, GaN surface down, on a medium tack tape, and the second would place the die, GaN surface up, on a high tack tape.
- a method for separating a semiconductor wafer using a patterned laser projection The patterned laser is incident substantially normal to a cutting surface of the wafer.
- the parameters of the laser system are set to maximize throughput without inducing damage to the wafer.
- the wafer itself is protected from cutting process effluent by the placement of a generally low tack adhesive tape on the cutting surface.
- a projection delivery system 130 uses optical element and masks to shape the laser emission into a linear pattern 900 .
- a gas jet nozzle 902 and vacuum hose 904 are arranged in alignment with the linear pattern from the projection delivery system.
- the jet nozzle projects an inert gas, identified by lines 906 , across the length of the path of the linear pattern.
- the gas is maintained at a level of 2 psi, which is of sufficient force to move particles into the mouth of the vacuum hose.
- nitrogen gas is preferred as it is relatively inexpensive, poses no health risks, and does not interfere with the ablation process.
- any inert gas may be used including, but limited to, helium, argon, krypton, and neon.
- the jets help to remove particles and smoke encountered during the laser ablation process, thereby reducing the cleaning conducted after separation. Additionally, the laser ablation process is improved due to removal of particles that would otherwise interfere and reduce the efficiency of the process.
- the wafer includes a layer of reflective metal 1010 applied to the substrate side of the wafer. Any reflective metal may be chosen; however, the metal selected preferably has reflection properties that are greatest for the wavelength of the light that is generated in the LED.
- a metal of the type suitable for this purpose is aluminum.
- the layer thickness is preferably within the range of 0-0.5 ⁇ m with a workable range of 0-1 ⁇ m.
- the tape 330 is applied to the reflective metal.
- the laser is applied from the side opposite the metal layer and as the laser is directed into the wafer laser light is reflected back from the reflective layer allowing for enhanced laser cutting efficiency on the epitaxial.
- Ablation occurs at the point where the energy density of the laser exceeds the energy density threshold for the material being ablated.
- the relatively transparent nature of the sapphire at the wavelength of the laser allows for laser energy to be reflected off of the metal layer and back towards the ablation point thereby increasing the energy density and improving the efficiency of the cutting process.
- the reflective metal is useful not only for wafer separation, but the material provides a reflective backing to the LED to direct more of the light out of the LED, thereby improving its output efficiency.
Abstract
A method for separating a semiconductor wafer into several thousand devices or die by laser ablation. Semiconductor wafers are initially pre-processed to create multiple devices, such as blue LEDs, on the wafers. The wafers are then mounted with tape coated with a generally high level adhesive. The mounted wafer is then placed on a vacuum chuck (which is itself positioned on a computer controlled positioning table) to hold it in place during the cutting process. The cutting surface is then covered with a protective layer to prevent contamination from the effluent resulting from the actual cutting process. A laser beam is generated and passed through optical elements and masks to create a pattern, such as a line or multiple lines. The patterned laser projection is directed at the wafer at a substantially normal angle and applied to the wafer until at least a partial cut is achieved through it. A mechanical separation process completes the separation when only a partial cut is achieved by the patterned laser projection. The die are then transferred to a grip ring for further processing.
Description
- This application is a continuation-in-part and claims the benefit of U.S. Application Ser. No. 09/178, 287 filed on Oct. 23, 1998 which is incorporated herein by reference.
- This invention relates to the field of semiconductor fabrication, and more particularly to semiconductor device separation.
- Sapphire wafers are an important semiconductor substrate. They are especially important for the development of gallium nitride based materials technology, which is used in blue spectrum light emitting diodes (LEDs). The production of high brightness LEDs in the blue spectrum is a relatively recent optoelectronics technology. The demand for nitride based LEDs, such as bright blue, bright green and other color LEDs, currently exceeds the industry's capability to supply them. Sapphire based device separation, however, remains a significant obstacle to efficient fabrication. Current separation techniques waste valuable wafer surface area, involve costly consumables, and have long process times.
- Semiconductor fabrication processes involve fabricating several thousand individual devices, or die, on one wafer. After processing and testing, the wafer may be thinned and the die must be separated from the wafer. Separation has been traditionally accomplished using either a dicing saw or a scribe-and-break process, both of which rely on diamond chips to cut the material. These two processes have been very effective on silicon and III-V substrates, because the material is much softer than diamond. However, sapphire's crystal structure, crystal orientation, inherent hardness, and material strength inhibit these methods from working well.
- Specifically, the diamond's edge dulls quickly when applied to sapphire. To compensate, dicing saw blades designed to cut sapphire contain diamonds in a resin matrix. The dicing blades wear quickly to constantly expose new, sharp diamonds. Although processing times and the number of blades is dependent on die size, studies have shown that completely dicing a 17 mil thick sapphire substrate into 16 mil×16 mil die would require up to four blades and over 2 hours of process time and the maximum yield would be 25%. A 4 mil thick sapphire substrate completely shatters during dicing. These low yields make it difficult to meet commercial demand. The yields are low because the minimum blade thickness is 8 mil. This results in a kerf width of >0.010″. Thinner blades, however, produce poor quality cuts. A significant amount of available device surface area is therefore wasted during wafer sawing.
- The scribe-and-break separation process also relies on a sharp diamond edge or facet. The scribe tip has a diamond head which is quickly dulled by the sapphire. This requires frequent and costly tip replacement. Due to these factors, a sapphire dicing process will produce too low a yield. Moreover, both the sawing and diamond scribing process become very complex due to diamond wear.
- Another method for device separation is discussed in U.S. Pat. Nos. 5,151,389 and 5,214,261, both of which are issued to Zapella. These references discuss a method for dicing semiconductor substrates using an excimer laser beam. This method uses a laser beam that is oriented out of normal with respect to the substrate to ensure non-tapered cuts. A drawback of this method is that the substrate and the laser beams must be maintained within the critical out of normal ranges. A further drawback is that a polyimide coating is used to prevent “dust” from settling onto the surface. The removal of this coating via chemical peeling introduces the possibility of contamination.
- The present invention is a method for efficient and inexpensive separation of semiconductor wafers by laser ablation. The method uses a laser to ablate material from the substrate, resulting in a separated wafer. Laser separation is advantageous because it permits processing of any sapphire based product, such as blue LEDs, inexpensively and quickly. Importantly, the separation methods are applicable to gallium arsenide (GaAs) and to other semiconductors with the same potential benefits of high throughputs, narrow kerfs and no cutting tips to wear.
- In an exemplary embodiment, the method of the present invention separates semiconductor wafers into a plurality of devices via laser ablation. A laser light emission is generated and sent through optical elements and masks to obtain a patterned laser projection. The patterned laser projection is then directed toward a given surface of a semiconductor wafer such that the patterned laser projection is substantially perpendicular to the given surface. The patterned laser projection is applied for a specified time at a specified power to obtain at least a partial cut through the semiconductor wafer. If the wafers are not fully cut using the laser, a mechanical method is then applied to complete the separation and create the die.
- Advantageously, the pattern of the laser projection can be selected in view of the type of semiconductor wafer. For example, the patterned laser projection of the present invention can be one long, narrow line that cuts several millimeters with one pulse or several smaller lines that cut several rows simultaneously with one pulse. Moreover, a protective layer is applied to the cutting surface to prevent cutting process effluent from contaminating the devices.
- The method of the present invention results in a kerf in the order of 10 μm wide if cut from a front surface and less than 10 μm if cut from a back or substrate surface. Consequently, the present invention reduces wastage of wafer space and permits more devices to be placed on the wafer. The above factors make the present invention an efficient, low maintenance and high production method for separating semiconductor wafers. Such a method is a significant step toward meeting the demand for sapphire based devices.
- In an alternate embodiment, a cleaning system is used during ablation to draw up particles and smoke to improve the ablation process and reduce post ablation cleaning of the material.
- In another embodiment, a reflector is applied to a wafer surface opposite the laser emission to reflect laser light back onto the wafer thereby making more efficient use of the laser emission.
- A more complete understanding of the present invention may be obtained from consideration of the following description in conjunction with the drawings in which:
- FIG. 1 is an exemplary embodiment of a laser-based semiconductor separation system in accordance with the present invention;
- FIG. 2 shows a more detailed view of a projection delivery system outputting a patterned light projection onto a surface of a semiconductor wafer in accordance with the present invention;
- FIG. 3 shows a cross-sectional view of a semiconductor wafer in accordance with the present invention;
- FIG. 4 graphically shows the steps involved in the method of the present invention;
- FIG. 5 shows one laser cut die in accordance with the present invention;
- FIG. 6 shows a plurality of laser cut die in accordance with the present invention;
- FIG. 7 shows a laser cut in GaN in accordance with the present invention;
- FIG. 8 shows a scanning electron microscope photo of a laser cut die in accordance with the present invention;
- FIG. 9 shows a more detailed view of an alternate projection delivery system outputting a patterned light projection onto a surface of a semiconductor wafer having a surface cleaning system in accordance with the present invention; and
- FIG. 10 shows an alternate cross-sectional view of a semiconductor wafer in accordance with the present invention.
- The following description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments disclosed, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
- For purposes of clarity, a top-level functional overview of the present invention is presented, followed by an exemplary embodiment of a laser-based semiconductor separation system incorporating the methodology of the present invention. A more detailed explanation of the methodology is then presented.
- In general, the method of the present invention separates a semiconductor wafer into several thousand devices or die by laser ablation. Semiconductor wafers are initially pre-processed to create multiple devices, such as blue LEDs, on the wafers. The wafers are then mounted with tape coated with a generally high level adhesive. The mounted wafer is then placed on a vacuum chuck (which is itself positioned on a computer controlled positioning table) to hold it in place during the cutting process. The cutting surface is then covered with a protective layer to prevent contamination from the effluent resulting from the actual cutting process. A laser light emission is generated and passed through optical elements and masks to create a pattern, such as a line or multiple lines. The patterned laser projection is directed at the wafer at a substantially normal angle and applied to the wafer until at least a partial cut is achieved through it. A mechanical separation process completes the separation when only a partial cut is achieved by the patterned laser projection. The die are then transferred to a grip ring for further processing.
- Referring to FIG. 1, there is shown an exemplary embodiment of a laser-based
separation system 100 that can be used in conjunction with the method of the present invention to separate asemiconductor wafer 105.System 100 includes alaser 110 coupled to acomputer control 120 and aprojection delivery system 130.Laser 110 is any laser that has the necessary parameters, for example, power, wavelength and frequency, to cut semiconductor wafers, such as but not limited to KrF lasers, Nd:YAG lasers, and other lasers. - As shown in more detail in FIG. 2,
projection delivery system 130 uses optical elements and masks to shape the laser light emission into apattern 200 that will optimize the cutting process onsemiconductor wafer 105. The optimal pattern may be either one long, narrow line that will cut several millimeters of the surface up to 100 μm deep with each pulse, or several smaller lines that will cut several rows simultaneously with each pulse. Other patterns, such as a grid pattern can also be used. The optimal configuration depends on the type of semiconductor wafer being separated. - Referring also to FIG. 1,
semiconductor wafer 105 is situated on avacuum chuck 140 to holdsemiconductor wafer 105 in place during the cutting process. Moreover, as explained below,vacuum chuck 105 flattens the shape ofsemiconductor wafer 105 during the cutting process.Vacuum chuck 140 is situated on a xyz theta positioning table 150.Computer control 120 controls the movement of xyz theta positioning table 150 with respect to patternedlight projection 155 so as to place the cuts in the correct areas. As the name of the table implies,computer control 120 movessemiconductor wafer 105 in the x, y and z axes and rotates it a given θ. This, along withvideo monitor 160 provides accurate control and placement of where patternedlight projection 155 will cutsemiconductor wafer 105. - Given the above laser-based semiconductor separation system, a more detailed explanation of the method of the present invention is presented. This explanation is given with respect to FIG. 3, which shows a cross-sectional view of a processed
semiconductor wafer 300 and FIG. 4, which illustrates graphically some of the steps in the method of the present invention. - Although the following description primarily refers to cutting gallium nitride (GaN) on C-plane sapphire, these are only illustrative materials. The epitaxial growth material can be, for example, any semiconductor material such as any of the III-V materials listed in the periodic chart of elements. The substrate material can be, for example, any of the III-V materials, refractory ceramics and any orientations of any of the listed substrate materials.
- Referring now to FIG. 3, a
semiconductor wafer 300 has afront surface 305, which is also referred to as the epi or epitaxial surface, and aback surface 310, which is also referred to as the substrate surface. Prior to cutting,GaN layer 315 will have been etched and coated with threemetal patterns 320 and a dielectric 350.Sapphire substrate 340 may be thinned from 0.017″ to 0.004″. The processing creates approximately 11000 devices on a 2″ diameter wafer. Due to lattice mismatch in the GaN/sapphire structure, the resulting stress in the structure causes the wafer to “bow”, such that it resembles a potato chip. - The bow in the wafer is flattened by a process termed wafer mounting. The wafer mounting process is also required to keep the 11000 individual devices in order. In an exemplary embodiment,
wafer 300 is mounted on 0.003″ to 0.005″thick tape 330 coated with a generally high tack adhesive. The mounting process is outlined below: - 1. Place wafer on mounting station.
- 2. Center dicing ring (which is a 9″ outer diameter, 8″ inner diameter and 0.10″ thick metal ring) around wafer.
- 3. Place a sheet of tape over wafer and ring.
- 4. Press tape onto ring and wafer.
- 5. Place a sheet of wax paper over the mounting structure (the adhesive side of the tape, wafer, and ring).
- 6. Cut out the center of the wax paper so the wafer is exposed.
- 7. Place mounting structure, wafer side up, on a vacuum chuck, which holds the structure in place and removes the wafer's bow.
- Note that the vacuum chuck can either be porous ceramic or contain concentric metal rings. The latter may require a backing so the ring pattern is not pressed into the tape.
- Because mounting
tape 330 is used, the parameters of the patterned laser projection are set in one embodiment of the method to achieve only a partial cut through the device. A mechanical breaking process is used to complete the separation. If a full or total cut through the wafer is desired, another layer must adhered on to the bottom of the mounting tape. This layer, for example, could be an epoxy or double sided tape. - Prior to the wafer mounting process, however, the user must decide which surface of the wafer to cut on. Whether to cut on the front surface or the back may depend upon the cut width or kerf that is produced for the particular type of wafer being cut. To minimize wafer wastage, the kerf value should be on the order of 10 μm wide. For example, front and back surface cuts should have kerf values of less than 100 μm. For the illustrative GaN/sapphire structure, the kerf value is about 20 μm when cutting from the front surface and less than 10 μm when cutting from the back surface. However, there are additional considerations that must be accounted for before deciding on which surface to cut on.
- Referring to Table 1, although cutting from the back surface results in a low kerf value, the resulting device edges are rough. This may decrease the performance of the device. With regard to blue LEDs, this means that the light output may be decreased. In contrast, the device edges are cleaner when cutting from the front surface. Consequently, this can increase the light output for the blue LEDs.
TABLE 1 Front Surface and Back Surface Cutting Cut surface Advantages Disadvantages Front - GaN Produces cleaner cut on Wider kerf (20 μm) surface device edge, which increases light output Back - sapphire Small kerf (<10 μm) Device edge rough, which surface because we are breaking may decrease light output. through GaN surface - Once the cutting surface has been selected, a protective layer must be placed on it. Studies have shown that the cutting process coats the wafer's surface with effluent, which is unacceptable. Generally, the wafer's surface is protected with either photoresist or polyimide during a laser separation process, and the coating is removed with a solvent after the process. This is not possible in the present case because the solvent may damage mounting
tape 330. The contamination problem is overcome by covering the cutting surface with a generally lowertack mounting tape 345. This provides excellent protection from effluent. Two pieces of tape were used for each wafer-one for X direction cutting and one for Y direction cutting. - Once the wafer is mounted and taped, it is placed on positioning table150.
Laser 110, for example, a KrF laser operating at 248 nm or a Nd:YAG operating at 1064 nm, is activated to generate laser light emission operable to cut the semiconductor wafer. The laser light emissions are fed throughprojection delivery system 130 to produce a pattern. The patterned light projection is then directed toward a selected cutting surface of the wafer so that it is substantially normal to the cutting surface. - The parameters of the laser, such as cutting speed, laser power, laser pulse rate, number of cuts, cut depth, etc., are set to achieve the required cut without inducing cracking and chipping. Studies using several types of laser sources have indicated that multiple shallow cuts, for example, cut depths of one mil to three mils for a 13 mil thick wafer, are required to separate sapphire based substrates without cracking. In contrast, deep cuts, for example, a 6 mil deep cut, caused cracks in the wafer. Studies have also shown that cut depths of 45 μm leave very little effluent on the surface. As stated above, this is a very important consideration in terms of contamination of the separated devices. In addition, the parameters are also set to achieve the desired partial or full cut through the wafer. As shown in FIG. 3,
cuts 360 are made through oxide layers 360. - Referring now to FIG. 4, a
graphical representation 400 of how a wafer is cut is shown. Starting with a mounted uncut wafer 410 (step 1),tape 420 is placed on the cutting surface of wafer 410 (step 2). Tapedwafer 430 is cut in the X direction (step 3) and the excess tape is removed (step 4). X cutwafer 440 is again covered with tape 420 (step 5) and is now cut in the Y direction (step 6). The excess tape is removed, leaving at least a partially cut wafer 450 (step 7). - Referring now to FIGS.5-6, the above method separates the entire wafer into square die. In an exemplary cut, the cuts are on 400 μm centers, in the X and Y directions. The cut depths are roughly 85 μm. The remaining 15 μm is mechanically broken using conventional techniques. A single laser cut die 500 is shown in FIG. 5 and a plurality of
die 600 are shown in FIG. 6. As indicated, the actual die size is 372 μm with a kerf width of 28 μm. Moreover, these photos show that the edges resulting from the laser cuts are sharp. FIG. 7 is an example of a laser cut in GaN that has a kerf width of 20 μm and FIG. 8 shows a scanning electron microscope photo of characteristic features of a laser cut surface. - After cutting, the wax paper is removed and the cut quality is inspected. The next steps depend on the wafer's orientation during cutting. If the wafer was mounted with the GaN surface on the mounting tape and cut from the back surface, the individual die must be remounted on tape with the GaN surface facing up. That is done using the following process:
- 1. Cover the mounting tape with clean wax paper.
- 2. Cut a hole in the wax paper to expose the wafer.
- 3. Cover the wafer, wax paper, and the ring with a tape that has higher adhesion than the tape on which the wafer was cut.
- 4. Wait until the adhesive strength of the new tape maximizes.
- 5. Peel off the tape on which the wafer was cut.
- 6. Transfer the wafer to a grip ring using commercial equipment.
- If the wafer was cut from the GaN surface and the mounting tape was not damaged, then the wafer and the tape on which it was cut is transferred to a grip ring. If the mounting tape was damaged, then two tape transfers are necessary. The first would place the die, GaN surface down, on a medium tack tape, and the second would place the die, GaN surface up, on a high tack tape.
- In accordance with the present invention, there has been described a method for separating a semiconductor wafer using a patterned laser projection. The patterned laser is incident substantially normal to a cutting surface of the wafer. The parameters of the laser system are set to maximize throughput without inducing damage to the wafer. The wafer itself is protected from cutting process effluent by the placement of a generally low tack adhesive tape on the cutting surface.
- In an alternate embodiment as shown in more detail in FIG. 9, a
projection delivery system 130 uses optical element and masks to shape the laser emission into alinear pattern 900. Agas jet nozzle 902 andvacuum hose 904 are arranged in alignment with the linear pattern from the projection delivery system. The jet nozzle projects an inert gas, identified bylines 906, across the length of the path of the linear pattern. The gas is maintained at a level of 2 psi, which is of sufficient force to move particles into the mouth of the vacuum hose. Presently, nitrogen gas is preferred as it is relatively inexpensive, poses no health risks, and does not interfere with the ablation process. However, it will be appreciated that any inert gas may be used including, but limited to, helium, argon, krypton, and neon. The jets help to remove particles and smoke encountered during the laser ablation process, thereby reducing the cleaning conducted after separation. Additionally, the laser ablation process is improved due to removal of particles that would otherwise interfere and reduce the efficiency of the process. - With reference to FIG. 10, an alternate embodiment of the semiconductor wafer of FIG. 3 is illustrated where like reference numerals refer to like structures. The wafer includes a layer of
reflective metal 1010 applied to the substrate side of the wafer. Any reflective metal may be chosen; however, the metal selected preferably has reflection properties that are greatest for the wavelength of the light that is generated in the LED. A metal of the type suitable for this purpose is aluminum. The layer thickness is preferably within the range of 0-0.5 μm with a workable range of 0-1 μm. Thetape 330 is applied to the reflective metal. The laser is applied from the side opposite the metal layer and as the laser is directed into the wafer laser light is reflected back from the reflective layer allowing for enhanced laser cutting efficiency on the epitaxial. Ablation occurs at the point where the energy density of the laser exceeds the energy density threshold for the material being ablated. The relatively transparent nature of the sapphire at the wavelength of the laser allows for laser energy to be reflected off of the metal layer and back towards the ablation point thereby increasing the energy density and improving the efficiency of the cutting process. The reflective metal is useful not only for wafer separation, but the material provides a reflective backing to the LED to direct more of the light out of the LED, thereby improving its output efficiency. - Numerous modifications and alternative embodiments of the invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Details of the structure may be varied substantially without departing from the spirit of the invention and the exclusive use of all modifications which come within the scope of the appended claims are reserved.
Claims (26)
1. A method for scribing a semiconductor wafer, said method comprising the steps of:
directing a patterned laser projection at a surface of said semiconductor wafer, said semiconductor wafer comprising a substrate layer and a device layer;
applying said patterned laser projection with a given set of parameters until at least a partial cut in said semiconductor wafer is obtained; and
blowing gas across the surface for removing particles during said partial cut.
2. The method of claim 1 , wherein said substrate layer comprises a sapphire substrate layer.
3. The method of claim 2 , wherein said device layer comprises a nitride device layer.
4. The method of claim 2 , further comprising the step of vacuuming said gas received from across the surface with a vacuum hose.
5. The method of claim 2 , wherein said blowing is performed by at least one jet nozzle.
6. The method according to claim 5 , wherein the blowing step adjusts said jet nozzle to blow gas at a rate greater than 2 psi.
7. The method of claim 2 , wherein said patterned laser projection is reflected back into the wafer from a reflector disposed near a second surface of said semiconductor wafer during the applying step.
8. A method for scribing a semiconductor wafer comprising a substrate layer and a device layer, said method comprising the steps of:
directing a patterned laser projection at said device layer of said semiconductor wafer;
applying said patterned laser projection with a given set of parameters until at least a partial cut in said semiconductor wafer is obtained; and
reflecting said patterned laser projection back into said semiconductor wafer during said partial cut.
9. The method of claim 8 , wherein said substrate layer comprises a sapphire substrate layer.
10. The method of claim 9 , wherein said device layer comprises a nitride device layer.
11. A method for preparing a semiconductor wafer comprising the steps of:
providing said semiconductor wafer, the providing step including the step of, on a substrate, depositing a device layer;
directing a laser through optical elements to form a patterned laser projection;
making a plurality of cuts in at least the substrate via laser ablation using the patterned laser projection; and
blowing gas across a surface of said semiconductor wafer for removing particles during said partial cut.
12. The method of claim 11 , wherein said substrate comprises a sapphire substrate layer.
13. The method of claim 12 , wherein said device layer comprises a nitride device layer.
14. The method of claim 12 , further comprising the step of vacuuming said gas received from across the surface with a vacuum hose.
15. A laser-based system for dicing semiconductor wafers, comprising:
a table for holding and positioning a semiconductor wafer having a plurality of devices, said semiconductor wafer comprising a substrate layer and a device layer;
a projection delivery system for directing a patterned laser projection to a surface of said semiconductor wafer;
a controller for applying said patterned laser projection in accordance with given parameters to achieve at least a partial cut through said semiconductor wafer; and
a cleaning system for removing particles during said partial cut.
16. The system of claim 15 , wherein said substrate layer comprises a sapphire substrate layer.
17. The system of claim 16 , wherein said device layer comprises a nitride device layer.
18. The system of claim 16 , wherein said cleaning system blows gas across the surface of the wafer.
19. The system of claim 16 , wherein said cleaning system includes at least one jet nozzle adapted to blow gas across the surface of the wafer.
20. The system of claim 16 , wherein said cleaning system includes at least one vacuum hose to remove particles from the surface being cut.
21. The system according to claim 16 , wherein said projection system includes a reflector underlying the wafer set on said table for reflecting said patterned laser projection back into the wafer to enhance the cutting process.
22. The system according to claim 21 , wherein said reflector is a reflective metal applied to a surface of said wafer.
23. A laser-based system for dicing semiconductor wafers, comprising:
a table for holding and positioning a semiconductor wafer having a plurality of devices, said semiconductor wafer comprising a substrate layer and a device layer;
a projection delivery system for directing a patterned laser projection at said device layer of said semiconductor wafer;
a controller for applying said patterned laser projection in accordance with given parameters to achieve at least a partial cut through said semiconductor wafer; and
a reflector in said substrate layer for reflecting said patterned laser projection back into said semiconductor wafer during said partial cut.
24. The system of claim of 23, wherein said substrate layer comprises a sapphire substrate layer.
25. The system of claim 24 , wherein said device layer comprises a nitride device layer.
26. The system according to claim 24 wherein said reflector is a reflective metal applied to a surface of said substrate.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/146,267 US20030003690A1 (en) | 1998-10-23 | 2002-05-15 | Semiconductor device separation using a patterned laser projection |
US11/123,796 US20050263854A1 (en) | 1998-10-23 | 2005-05-06 | Thick laser-scribed GaN-on-sapphire optoelectronic devices |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/178,287 US6413839B1 (en) | 1998-10-23 | 1998-10-23 | Semiconductor device separation using a patterned laser projection |
US10/146,267 US20030003690A1 (en) | 1998-10-23 | 2002-05-15 | Semiconductor device separation using a patterned laser projection |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/178,287 Continuation-In-Part US6413839B1 (en) | 1998-10-23 | 1998-10-23 | Semiconductor device separation using a patterned laser projection |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/123,796 Continuation-In-Part US20050263854A1 (en) | 1998-10-23 | 2005-05-06 | Thick laser-scribed GaN-on-sapphire optoelectronic devices |
Publications (1)
Publication Number | Publication Date |
---|---|
US20030003690A1 true US20030003690A1 (en) | 2003-01-02 |
Family
ID=22651952
Family Applications (5)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/178,287 Expired - Lifetime US6413839B1 (en) | 1998-10-23 | 1998-10-23 | Semiconductor device separation using a patterned laser projection |
US10/114,099 Expired - Lifetime US6902990B2 (en) | 1998-10-23 | 2002-04-02 | Semiconductor device separation using a patterned laser projection |
US10/137,904 Expired - Lifetime US6849524B2 (en) | 1998-10-23 | 2002-05-02 | Semiconductor wafer protection and cleaning for device separation using laser ablation |
US10/146,267 Abandoned US20030003690A1 (en) | 1998-10-23 | 2002-05-15 | Semiconductor device separation using a patterned laser projection |
US10/845,790 Abandoned US20050003634A1 (en) | 1998-10-23 | 2004-05-13 | Semiconductor device separation using a patterned laser projection |
Family Applications Before (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/178,287 Expired - Lifetime US6413839B1 (en) | 1998-10-23 | 1998-10-23 | Semiconductor device separation using a patterned laser projection |
US10/114,099 Expired - Lifetime US6902990B2 (en) | 1998-10-23 | 2002-04-02 | Semiconductor device separation using a patterned laser projection |
US10/137,904 Expired - Lifetime US6849524B2 (en) | 1998-10-23 | 2002-05-02 | Semiconductor wafer protection and cleaning for device separation using laser ablation |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/845,790 Abandoned US20050003634A1 (en) | 1998-10-23 | 2004-05-13 | Semiconductor device separation using a patterned laser projection |
Country Status (2)
Country | Link |
---|---|
US (5) | US6413839B1 (en) |
TW (1) | TW521334B (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040224508A1 (en) * | 2003-05-06 | 2004-11-11 | Applied Materials Israel Ltd | Apparatus and method for cleaning a substrate using a homogenized and non-polarized radiation beam |
US20040253796A1 (en) * | 2003-06-10 | 2004-12-16 | Na Jeong Seok | Method for manufacturing gallium nitride (GaN) based single crystalline substrate |
US20050093016A1 (en) * | 2003-11-05 | 2005-05-05 | Sharp Kabushiki Kaisha | Nitride semiconductor light-emitting diode chip and method of manufacturing the same |
US20050242073A1 (en) * | 2004-04-28 | 2005-11-03 | Disco Corporation | Laser beam processing method |
US20050263854A1 (en) * | 1998-10-23 | 2005-12-01 | Shelton Bryan S | Thick laser-scribed GaN-on-sapphire optoelectronic devices |
US20060030125A1 (en) * | 2004-08-04 | 2006-02-09 | Gelcore, Llc | Laser separation of encapsulated submount |
US20060154390A1 (en) * | 2005-01-11 | 2006-07-13 | Tran Chuong A | Systems and methods for producing light emitting diode array |
US20070161211A1 (en) * | 2006-01-06 | 2007-07-12 | Masahiro Sunohara | Method for manufacturing semiconductor device |
US20070235430A1 (en) * | 2006-04-10 | 2007-10-11 | Disco Corporation | Laser beam processing machine |
CN100389485C (en) * | 2003-12-27 | 2008-05-21 | 上海华虹(集团)有限公司 | Method for producing integrated circuit sample section using laser |
US20080237189A1 (en) * | 2007-03-30 | 2008-10-02 | Oc Oerlikon Balzers Ag | Method for laser scribing of solar panels |
US20100258539A1 (en) * | 2007-07-18 | 2010-10-14 | Hamamatsu Photonics K.K. | Machining information supply equipment and supply system |
WO2015072598A1 (en) * | 2013-11-14 | 2015-05-21 | (주)정원기술 | Laser optic device for bonding flip chip by laser pressing |
CN113782654A (en) * | 2021-09-13 | 2021-12-10 | 錼创显示科技股份有限公司 | Light emitting diode structure and manufacturing method thereof |
TWI782703B (en) * | 2021-09-13 | 2022-11-01 | 錼創顯示科技股份有限公司 | Light-emitting diode structure and manufacturing method thereof |
WO2024006962A3 (en) * | 2022-06-30 | 2024-02-29 | University Of Virginia Patent Foundation | Use of lasers to selectively remove materials from substrates |
Families Citing this family (136)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4659300B2 (en) | 2000-09-13 | 2011-03-30 | 浜松ホトニクス株式会社 | Laser processing method and semiconductor chip manufacturing method |
TW504774B (en) * | 2001-07-05 | 2002-10-01 | Chipbond Technology Corp | System and method of laser die-sintering and the die sintered by laser |
US6744072B2 (en) * | 2001-10-02 | 2004-06-01 | Xerox Corporation | Substrates having increased thermal conductivity for semiconductor structures |
ES2377521T3 (en) | 2002-03-12 | 2012-03-28 | Hamamatsu Photonics K.K. | Method to divide a substrate |
US7749867B2 (en) | 2002-03-12 | 2010-07-06 | Hamamatsu Photonics K.K. | Method of cutting processed object |
TWI326626B (en) * | 2002-03-12 | 2010-07-01 | Hamamatsu Photonics Kk | Laser processing method |
JP2005523583A (en) * | 2002-04-19 | 2005-08-04 | エグシル テクノロジー リミテッド | Programmed dicing of substrates using pulsed laser |
US6580054B1 (en) * | 2002-06-10 | 2003-06-17 | New Wave Research | Scribing sapphire substrates with a solid state UV laser |
US6806544B2 (en) * | 2002-11-05 | 2004-10-19 | New Wave Research | Method and apparatus for cutting devices from conductive substrates secured during cutting by vacuum pressure |
US6960813B2 (en) * | 2002-06-10 | 2005-11-01 | New Wave Research | Method and apparatus for cutting devices from substrates |
US6995032B2 (en) * | 2002-07-19 | 2006-02-07 | Cree, Inc. | Trench cut light emitting diodes and methods of fabricating same |
JP2004160483A (en) * | 2002-11-12 | 2004-06-10 | Disco Abrasive Syst Ltd | Laser beam machining method, and laser beam machining apparatus |
TWI520269B (en) | 2002-12-03 | 2016-02-01 | Hamamatsu Photonics Kk | Cutting method of semiconductor substrate |
CN1729582A (en) * | 2002-12-20 | 2006-02-01 | 克里公司 | Methods of forming electronic devices including semiconductor mesa structures and conductivity junctions and related devices |
TWI248244B (en) * | 2003-02-19 | 2006-01-21 | J P Sercel Associates Inc | System and method for cutting using a variable astigmatic focal beam spot |
FR2852250B1 (en) | 2003-03-11 | 2009-07-24 | Jean Luc Jouvin | PROTECTIVE SHEATH FOR CANNULA, AN INJECTION KIT COMPRISING SUCH ANKLE AND NEEDLE EQUIPPED WITH SUCH ANKLE |
US8685838B2 (en) * | 2003-03-12 | 2014-04-01 | Hamamatsu Photonics K.K. | Laser beam machining method |
EP1634673A4 (en) * | 2003-04-25 | 2009-04-08 | Nitto Denko Corp | Method of producing laser-processed product and adhesive sheet, for laser processing used therefor |
GB2404280B (en) * | 2003-07-03 | 2006-09-27 | Xsil Technology Ltd | Die bonding |
JP2005032903A (en) * | 2003-07-10 | 2005-02-03 | Oki Electric Ind Co Ltd | Semiconductor device and its manufacturing method |
US6949449B2 (en) * | 2003-07-11 | 2005-09-27 | Electro Scientific Industries, Inc. | Method of forming a scribe line on a ceramic substrate |
US20050029646A1 (en) * | 2003-08-07 | 2005-02-10 | Matsushita Electric Industrial Co., Ltd. | Semiconductor device and method for dividing substrate |
KR100537494B1 (en) * | 2003-10-02 | 2005-12-19 | (주)한빛레이저 | The method for Silicon wafer laser dicing with surfactant coating |
US6956210B2 (en) * | 2003-10-15 | 2005-10-18 | Micron Tchnology, Inc. | Methods for preparing samples for atom probe analysis |
US7064010B2 (en) * | 2003-10-20 | 2006-06-20 | Micron Technology, Inc. | Methods of coating and singulating wafers |
US7008861B2 (en) * | 2003-12-11 | 2006-03-07 | Cree, Inc. | Semiconductor substrate assemblies and methods for preparing and dicing the same |
WO2005063435A1 (en) * | 2003-12-25 | 2005-07-14 | Nitto Denko Corporation | Laser processing protection sheet and production methodfor laser processed article |
US7202141B2 (en) * | 2004-03-29 | 2007-04-10 | J.P. Sercel Associates, Inc. | Method of separating layers of material |
US7700413B2 (en) * | 2004-04-20 | 2010-04-20 | Showa Denko K.K. | Production method of compound semiconductor light-emitting device wafer |
JP2005322738A (en) * | 2004-05-07 | 2005-11-17 | Toshiba Corp | Manufacturing method of semiconductor device |
US7459377B2 (en) * | 2004-06-08 | 2008-12-02 | Panasonic Corporation | Method for dividing substrate |
JP4890746B2 (en) * | 2004-06-14 | 2012-03-07 | 株式会社ディスコ | Wafer processing method |
US8383982B2 (en) * | 2004-06-18 | 2013-02-26 | Electro Scientific Industries, Inc. | Methods and systems for semiconductor structure processing using multiple laser beam spots |
US7435927B2 (en) | 2004-06-18 | 2008-10-14 | Electron Scientific Industries, Inc. | Semiconductor link processing using multiple laterally spaced laser beam spots with on-axis offset |
US7935941B2 (en) * | 2004-06-18 | 2011-05-03 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laser beam spots spaced on-axis on non-adjacent structures |
US7687740B2 (en) * | 2004-06-18 | 2010-03-30 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laterally spaced laser beam spots delivering multiple blows |
US7425471B2 (en) * | 2004-06-18 | 2008-09-16 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laser beam spots spaced on-axis with cross-axis offset |
US7629234B2 (en) * | 2004-06-18 | 2009-12-08 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laterally spaced laser beam spots with joint velocity profiling |
US8148211B2 (en) * | 2004-06-18 | 2012-04-03 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laser beam spots spaced on-axis delivered simultaneously |
US7633034B2 (en) * | 2004-06-18 | 2009-12-15 | Electro Scientific Industries, Inc. | Semiconductor structure processing using multiple laser beam spots overlapping lengthwise on a structure |
US7550367B2 (en) * | 2004-08-17 | 2009-06-23 | Denso Corporation | Method for separating semiconductor substrate |
KR20070073764A (en) * | 2004-10-05 | 2007-07-10 | 코닌클리케 필립스 일렉트로닉스 엔.브이. | Method for laser dicing of a substrate |
GB2420443B (en) * | 2004-11-01 | 2009-09-16 | Xsil Technology Ltd | Increasing die strength by etching during or after dicing |
KR20060040277A (en) * | 2004-11-05 | 2006-05-10 | 엘지.필립스 엘시디 주식회사 | Method for cutting of substrate using femtosecond laser |
TWI290500B (en) * | 2004-12-14 | 2007-12-01 | Arima Optoelectronics Corp | Laser dicing apparatus for a silicon wafer and dicing method thereof |
TWI237322B (en) * | 2004-12-14 | 2005-08-01 | Cleavage Entpr Co Ltd | Method and device by using a laser beam to cut Gallium arsenide (GaAs) epitaxy wafer |
TWI255749B (en) * | 2004-12-14 | 2006-06-01 | Cleavage Entpr Co Ltd | High-power solid-state laser dicing apparatus for a gallium nitride wafer and dicing method thereof |
TWI237852B (en) * | 2004-12-14 | 2005-08-11 | Cleavage Entpr Co Ltd | Device utilizing high power laser to manufacture dies and its production method |
JP4854061B2 (en) * | 2005-01-14 | 2012-01-11 | 日東電工株式会社 | Manufacturing method of laser processed product and protective sheet for laser processing |
JP4873863B2 (en) * | 2005-01-14 | 2012-02-08 | 日東電工株式会社 | Manufacturing method of laser processed product and pressure-sensitive adhesive sheet for laser processing |
JP4728671B2 (en) * | 2005-03-11 | 2011-07-20 | 日本メクトロン株式会社 | Flexible printed circuit board transfer device |
NL1028588C2 (en) * | 2005-03-22 | 2006-09-25 | Fico Bv | Method and device for separating products with a controlled cut edge and separated product. |
US20060289966A1 (en) * | 2005-06-22 | 2006-12-28 | Dani Ashay A | Silicon wafer with non-soluble protective coating |
JP5022576B2 (en) * | 2005-07-08 | 2012-09-12 | 株式会社ジャパンディスプレイイースト | Display panel and display device |
JP2007036143A (en) * | 2005-07-29 | 2007-02-08 | Disco Abrasive Syst Ltd | Machining method of semiconductor wafer |
KR100674440B1 (en) * | 2005-08-12 | 2007-01-25 | 주식회사 파이컴 | Probe card manufacture method and device |
US8778780B1 (en) * | 2005-10-13 | 2014-07-15 | SemiLEDs Optoelectronics Co., Ltd. | Method for defining semiconductor devices |
TWI270223B (en) * | 2005-11-21 | 2007-01-01 | Epistar Corp | A method of making a light emitting element |
US7682937B2 (en) * | 2005-11-25 | 2010-03-23 | Advanced Laser Separation International B.V. | Method of treating a substrate, method of processing a substrate using a laser beam, and arrangement |
CN100407461C (en) * | 2005-11-28 | 2008-07-30 | 晶元光电股份有限公司 | Method for producing luminous element with high-illuminating effect |
JP2007173465A (en) * | 2005-12-21 | 2007-07-05 | Rohm Co Ltd | Manufacturing method of nitride semiconductor light-emitting element |
NL2000039C2 (en) * | 2006-03-28 | 2007-10-01 | Fico Bv | Method and device for shielding encapsulated electronic components during laser cutting. |
US20070272666A1 (en) * | 2006-05-25 | 2007-11-29 | O'brien James N | Infrared laser wafer scribing using short pulses |
US7892891B2 (en) * | 2006-10-11 | 2011-02-22 | SemiLEDs Optoelectronics Co., Ltd. | Die separation |
US8486742B2 (en) | 2006-11-21 | 2013-07-16 | Epistar Corporation | Method for manufacturing high efficiency light-emitting diodes |
US8043878B2 (en) * | 2006-11-21 | 2011-10-25 | Epistar Corporation | Method for manufacturing high efficiency light-emitting diodes |
KR100825798B1 (en) * | 2006-12-29 | 2008-04-28 | 삼성전자주식회사 | Method of dicing |
JPWO2008152945A1 (en) * | 2007-06-15 | 2010-08-26 | ローム株式会社 | Semiconductor light emitting device and manufacturing method thereof |
US20080314311A1 (en) * | 2007-06-24 | 2008-12-25 | Burrows Brian H | Hvpe showerhead design |
WO2009014707A2 (en) | 2007-07-23 | 2009-01-29 | Qd Vision, Inc. | Quantum dot light enhancement substrate and lighting device including same |
US20090149008A1 (en) * | 2007-10-05 | 2009-06-11 | Applied Materials, Inc. | Method for depositing group iii/v compounds |
KR101485451B1 (en) * | 2007-12-19 | 2015-01-23 | 가부시키가이샤 토쿄 세이미쯔 | Laser dicing apparatus and dicing method |
US20100078418A1 (en) * | 2008-09-26 | 2010-04-01 | Electro Scientific Industries, Inc. | Method of laser micro-machining stainless steel with high cosmetic quality |
US20110300692A1 (en) * | 2008-10-29 | 2011-12-08 | Oerlikon Solar Ag, Trubbach | Method for dividing a semiconductor film formed on a substrate into plural regions by multiple laser beam irradiation |
US7960201B2 (en) * | 2009-01-29 | 2011-06-14 | Emcore Solar Power, Inc. | String interconnection and fabrication of inverted metamorphic multijunction solar cells |
TWI470823B (en) * | 2009-02-11 | 2015-01-21 | Epistar Corp | Light-emitting device and manufacturing method thereof |
US8247886B1 (en) | 2009-03-09 | 2012-08-21 | Soraa, Inc. | Polarization direction of optical devices using selected spatial configurations |
US8609512B2 (en) * | 2009-03-27 | 2013-12-17 | Electro Scientific Industries, Inc. | Method for laser singulation of chip scale packages on glass substrates |
US8183132B2 (en) * | 2009-04-10 | 2012-05-22 | Applied Materials, Inc. | Methods for fabricating group III nitride structures with a cluster tool |
US8491720B2 (en) * | 2009-04-10 | 2013-07-23 | Applied Materials, Inc. | HVPE precursor source hardware |
US8138069B2 (en) * | 2009-04-24 | 2012-03-20 | Applied Materials, Inc. | Substrate pretreatment for subsequent high temperature group III depositions |
US20100273291A1 (en) * | 2009-04-28 | 2010-10-28 | Applied Materials, Inc. | Decontamination of mocvd chamber using nh3 purge after in-situ cleaning |
WO2010127156A2 (en) * | 2009-04-29 | 2010-11-04 | Applied Materials, Inc. | Method of forming in-situ pre-gan deposition layer in hvpe |
US8216867B2 (en) * | 2009-06-10 | 2012-07-10 | Cree, Inc. | Front end scribing of light emitting diode (LED) wafers and resulting devices |
US8444850B2 (en) * | 2009-08-17 | 2013-05-21 | Exxonmobil Research And Engineering Company | Operating method for hydrodenitrogenation |
JP5446631B2 (en) * | 2009-09-10 | 2014-03-19 | アイシン精機株式会社 | Laser processing method and laser processing apparatus |
US9583678B2 (en) | 2009-09-18 | 2017-02-28 | Soraa, Inc. | High-performance LED fabrication |
US8334162B2 (en) | 2009-09-22 | 2012-12-18 | First Solar, Inc | System and method for tracking and removing coating from an edge of a substrate |
US20130256286A1 (en) * | 2009-12-07 | 2013-10-03 | Ipg Microsystems Llc | Laser processing using an astigmatic elongated beam spot and using ultrashort pulses and/or longer wavelengths |
JP2011134955A (en) * | 2009-12-25 | 2011-07-07 | Disco Abrasive Syst Ltd | Method of producing chip component from plate material |
US10147850B1 (en) | 2010-02-03 | 2018-12-04 | Soraa, Inc. | System and method for providing color light sources in proximity to predetermined wavelength conversion structures |
JP2011204806A (en) * | 2010-03-24 | 2011-10-13 | Nitto Denko Corp | Processing method of wafer |
US20110256692A1 (en) | 2010-04-14 | 2011-10-20 | Applied Materials, Inc. | Multiple precursor concentric delivery showerhead |
US9190560B2 (en) | 2010-05-18 | 2015-11-17 | Agency For Science Technology And Research | Method of forming a light emitting diode structure and a light diode structure |
US9450143B2 (en) | 2010-06-18 | 2016-09-20 | Soraa, Inc. | Gallium and nitrogen containing triangular or diamond-shaped configuration for optical devices |
EP2409808A1 (en) | 2010-07-22 | 2012-01-25 | Bystronic Laser AG | Laser processing machine |
TWI447845B (en) * | 2010-09-24 | 2014-08-01 | Powertech Technology Inc | Chuck table and method for unloading wafer using the same |
US9287175B2 (en) | 2010-11-05 | 2016-03-15 | Win Semiconductors Corp. | Fabrication method for dicing of semiconductor wafers using laser cutting techniques |
TWI438836B (en) * | 2010-11-05 | 2014-05-21 | Win Semiconductors Corp | A fabrication method for dicing of semiconductor wafers using laser cutting techniques |
CN102569544A (en) * | 2010-12-27 | 2012-07-11 | 同方光电科技有限公司 | Method for manufacturing individual light-emitting diodes |
US8786053B2 (en) | 2011-01-24 | 2014-07-22 | Soraa, Inc. | Gallium-nitride-on-handle substrate materials and devices and method of manufacture |
TWI534291B (en) | 2011-03-18 | 2016-05-21 | 應用材料股份有限公司 | Showerhead assembly |
US8686431B2 (en) | 2011-08-22 | 2014-04-01 | Soraa, Inc. | Gallium and nitrogen containing trilateral configuration for optical devices |
US9646827B1 (en) | 2011-08-23 | 2017-05-09 | Soraa, Inc. | Method for smoothing surface of a substrate containing gallium and nitrogen |
US8728849B1 (en) | 2011-08-31 | 2014-05-20 | Alta Devices, Inc. | Laser cutting through two dissimilar materials separated by a metal foil |
US8728933B1 (en) | 2011-08-31 | 2014-05-20 | Alta Devices, Inc. | Laser cutting and chemical edge clean for thin-film solar cells |
US8361828B1 (en) | 2011-08-31 | 2013-01-29 | Alta Devices, Inc. | Aligned frontside backside laser dicing of semiconductor films |
US8399281B1 (en) | 2011-08-31 | 2013-03-19 | Alta Devices, Inc. | Two beam backside laser dicing of semiconductor films |
US8912025B2 (en) * | 2011-11-23 | 2014-12-16 | Soraa, Inc. | Method for manufacture of bright GaN LEDs using a selective removal process |
US10052848B2 (en) | 2012-03-06 | 2018-08-21 | Apple Inc. | Sapphire laminates |
US9595636B2 (en) | 2012-03-28 | 2017-03-14 | Sensor Electronic Technology, Inc. | Light emitting device substrate with inclined sidewalls |
US10096742B2 (en) | 2012-03-28 | 2018-10-09 | Sensor Electronic Technology, Inc. | Light emitting device substrate with inclined sidewalls |
CN104470713B (en) | 2012-05-03 | 2019-02-05 | 3M创新有限公司 | Durable solar energy specular reflection film |
CN104334350A (en) * | 2012-05-03 | 2015-02-04 | 3M创新有限公司 | Durable solar mirror films |
US9221289B2 (en) | 2012-07-27 | 2015-12-29 | Apple Inc. | Sapphire window |
RU2509391C1 (en) * | 2012-09-21 | 2014-03-10 | Федеральное государственное бюджетное учреждение науки Институт физики полупроводников им. А.В. Ржанова Сибирского отделения Российской академии наук (ИФП СО РАН) | Method of forming chip boundaries for inlaid photodetector modules |
US9978904B2 (en) | 2012-10-16 | 2018-05-22 | Soraa, Inc. | Indium gallium nitride light emitting devices |
US9232672B2 (en) | 2013-01-10 | 2016-01-05 | Apple Inc. | Ceramic insert control mechanism |
JP6062315B2 (en) * | 2013-04-24 | 2017-01-18 | 株式会社ディスコ | Wafer processing method |
US8994033B2 (en) | 2013-07-09 | 2015-03-31 | Soraa, Inc. | Contacts for an n-type gallium and nitrogen substrate for optical devices |
DE102013108583A1 (en) * | 2013-08-08 | 2015-03-05 | Osram Opto Semiconductors Gmbh | Method for separating a composite into semiconductor chips and semiconductor chip |
US9678540B2 (en) | 2013-09-23 | 2017-06-13 | Apple Inc. | Electronic component embedded in ceramic material |
US9632537B2 (en) | 2013-09-23 | 2017-04-25 | Apple Inc. | Electronic component embedded in ceramic material |
US9419189B1 (en) | 2013-11-04 | 2016-08-16 | Soraa, Inc. | Small LED source with high brightness and high efficiency |
US9154678B2 (en) | 2013-12-11 | 2015-10-06 | Apple Inc. | Cover glass arrangement for an electronic device |
EP2883647B1 (en) | 2013-12-12 | 2019-05-29 | Bystronic Laser AG | Method for configuring a laser machining device |
US9225056B2 (en) | 2014-02-12 | 2015-12-29 | Apple Inc. | Antenna on sapphire structure |
US9601437B2 (en) * | 2014-09-09 | 2017-03-21 | Nxp B.V. | Plasma etching and stealth dicing laser process |
US10406634B2 (en) | 2015-07-01 | 2019-09-10 | Apple Inc. | Enhancing strength in laser cutting of ceramic components |
JP2018060993A (en) * | 2016-09-29 | 2018-04-12 | 東レエンジニアリング株式会社 | Transfer method, mounting method, transfer device, and mounting device |
CN108269888B (en) * | 2016-12-31 | 2020-02-14 | 山东华光光电子股份有限公司 | Method for preparing sapphire patterned substrate by utilizing laser etching and application |
JP2019033134A (en) * | 2017-08-04 | 2019-02-28 | 株式会社ディスコ | Wafer generation method |
DE102019130898A1 (en) | 2019-08-16 | 2021-02-18 | Infineon Technologies Ag | TWO-STAGE LASER PROCESSING OF AN ENCAPSULATING AGENT OF A SEMICONDUCTOR CHIP HOUSING |
KR20210135128A (en) | 2020-05-04 | 2021-11-12 | 삼성전자주식회사 | semiconductor package and method for manufacturing the same |
KR20220008501A (en) | 2020-07-14 | 2022-01-21 | 삼성전자주식회사 | semiconductor package |
CN112122797A (en) * | 2020-09-24 | 2020-12-25 | 松山湖材料实验室 | Laser processing slag removal method, system, computer device and readable storage medium |
Citations (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3629545A (en) * | 1967-12-19 | 1971-12-21 | Western Electric Co | Laser substrate parting |
US3699644A (en) * | 1971-01-04 | 1972-10-24 | Sylvania Electric Prod | Method of dividing wafers |
US3824678A (en) * | 1970-08-31 | 1974-07-23 | North American Rockwell | Process for laser scribing beam lead semiconductor wafers |
US3970819A (en) * | 1974-11-25 | 1976-07-20 | International Business Machines Corporation | Backside laser dicing system |
US4046985A (en) * | 1974-11-25 | 1977-09-06 | International Business Machines Corporation | Semiconductor wafer alignment apparatus |
US4224101A (en) * | 1976-09-03 | 1980-09-23 | U.S. Philips Corporation | Method of manufacturing semiconductor devices using laser beam cutting |
US4543464A (en) * | 1982-07-19 | 1985-09-24 | Tokyo Shibaura Denki Kabushiki Kaisha | Apparatus for scribing semiconductor wafer with laser beam |
US4729971A (en) * | 1987-03-31 | 1988-03-08 | Microwave Semiconductor Corporation | Semiconductor wafer dicing techniques |
US4851371A (en) * | 1988-12-05 | 1989-07-25 | Xerox Corporation | Fabricating process for large array semiconductive devices |
US4865686A (en) * | 1986-09-26 | 1989-09-12 | Semiconductor Energy Laboratory Co., Ltd. | Laser scribing method |
US4964212A (en) * | 1988-09-29 | 1990-10-23 | Commissariat A L'energie Atomique | Process for producing electrical connections through a substrate |
US4992393A (en) * | 1989-06-01 | 1991-02-12 | Ricoh Company, Ltd. | Method for producing semiconductor thin film by melt and recrystallization process |
US5075201A (en) * | 1990-10-31 | 1991-12-24 | Grumman Aerospace Corporation | Method for aligning high density infrared detector arrays |
US5151389A (en) * | 1990-09-10 | 1992-09-29 | Rockwell International Corporation | Method for dicing semiconductor substrates using an excimer laser beam |
US5185295A (en) * | 1990-05-16 | 1993-02-09 | Kabushiki Kaisha Toshiba | Method for dicing semiconductor substrates using a laser scribing and dual etch process |
US5214261A (en) * | 1990-09-10 | 1993-05-25 | Rockwell International Corporation | Method and apparatus for dicing semiconductor substrates using an excimer laser beam |
US5385633A (en) * | 1990-03-29 | 1995-01-31 | The United States Of America As Represented By The Secretary Of The Navy | Method for laser-assisted silicon etching using halocarbon ambients |
US5543365A (en) * | 1994-12-02 | 1996-08-06 | Texas Instruments Incorporated | Wafer scribe technique using laser by forming polysilicon |
US5552345A (en) * | 1993-09-22 | 1996-09-03 | Harris Corporation | Die separation method for silicon on diamond circuit structures |
US5631190A (en) * | 1994-10-07 | 1997-05-20 | Cree Research, Inc. | Method for producing high efficiency light-emitting diodes and resulting diode structures |
US5641416A (en) * | 1995-10-25 | 1997-06-24 | Micron Display Technology, Inc. | Method for particulate-free energy beam cutting of a wafer of die assemblies |
US5864171A (en) * | 1995-03-30 | 1999-01-26 | Kabushiki Kaisha Toshiba | Semiconductor optoelectric device and method of manufacturing the same |
US5872046A (en) * | 1996-04-10 | 1999-02-16 | Texas Instruments Incorporated | Method of cleaning wafer after partial saw |
US5916460A (en) * | 1995-07-07 | 1999-06-29 | Hitachi Cable, Ltd. | Method and apparatus for dicing a substrate |
US5922224A (en) * | 1996-02-09 | 1999-07-13 | U.S. Philips Corporation | Laser separation of semiconductor elements formed in a wafer of semiconductor material |
US5932118A (en) * | 1994-05-16 | 1999-08-03 | Sanyo Electric Co., Ltd. | Photoprocessing method |
US5976691A (en) * | 1996-12-19 | 1999-11-02 | Lintec Corporation | Process for producing chip and pressure sensitive adhesive sheet for said process |
US6117347A (en) * | 1996-07-10 | 2000-09-12 | Nec Corporation | Method of separating wafers into individual die |
US6140151A (en) * | 1998-05-22 | 2000-10-31 | Micron Technology, Inc. | Semiconductor wafer processing method |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61219535A (en) | 1985-03-26 | 1986-09-29 | Toshiba Corp | Manufacture of blanking die |
CA1269164A (en) * | 1986-03-24 | 1990-05-15 | Metin Aktik | Photosensitive diode with hydrogenated amorphous silicon layer |
JPH07100234B2 (en) | 1987-01-14 | 1995-11-01 | 株式会社ダイヘン | Laser beam cutting method for alloy steel |
JPS63183885A (en) | 1987-01-26 | 1988-07-29 | Nec Corp | Method of marking on semiconductor substrate |
US5974069A (en) * | 1994-09-16 | 1999-10-26 | Rohm Co., Ltd | Semiconductor laser and manufacturing method thereof |
US5597767A (en) * | 1995-01-06 | 1997-01-28 | Texas Instruments Incorporated | Separation of wafer into die with wafer-level processing |
JPH09298339A (en) * | 1996-04-30 | 1997-11-18 | Rohm Co Ltd | Manufacture of semiconductor laser |
JP4203132B2 (en) * | 1997-03-31 | 2008-12-24 | シャープ株式会社 | Light emitting device and manufacturing method thereof |
US6063696A (en) * | 1997-05-07 | 2000-05-16 | Texas Instruments Incorporated | Method of reducing wafer particles after partial saw using a superhard protective coating |
-
1998
- 1998-10-23 US US09/178,287 patent/US6413839B1/en not_active Expired - Lifetime
-
2001
- 2001-12-03 TW TW090129808A patent/TW521334B/en not_active IP Right Cessation
-
2002
- 2002-04-02 US US10/114,099 patent/US6902990B2/en not_active Expired - Lifetime
- 2002-05-02 US US10/137,904 patent/US6849524B2/en not_active Expired - Lifetime
- 2002-05-15 US US10/146,267 patent/US20030003690A1/en not_active Abandoned
-
2004
- 2004-05-13 US US10/845,790 patent/US20050003634A1/en not_active Abandoned
Patent Citations (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3629545A (en) * | 1967-12-19 | 1971-12-21 | Western Electric Co | Laser substrate parting |
US3824678A (en) * | 1970-08-31 | 1974-07-23 | North American Rockwell | Process for laser scribing beam lead semiconductor wafers |
US3699644A (en) * | 1971-01-04 | 1972-10-24 | Sylvania Electric Prod | Method of dividing wafers |
US3970819A (en) * | 1974-11-25 | 1976-07-20 | International Business Machines Corporation | Backside laser dicing system |
US4046985A (en) * | 1974-11-25 | 1977-09-06 | International Business Machines Corporation | Semiconductor wafer alignment apparatus |
US4224101A (en) * | 1976-09-03 | 1980-09-23 | U.S. Philips Corporation | Method of manufacturing semiconductor devices using laser beam cutting |
US4543464A (en) * | 1982-07-19 | 1985-09-24 | Tokyo Shibaura Denki Kabushiki Kaisha | Apparatus for scribing semiconductor wafer with laser beam |
US4865686A (en) * | 1986-09-26 | 1989-09-12 | Semiconductor Energy Laboratory Co., Ltd. | Laser scribing method |
US4729971A (en) * | 1987-03-31 | 1988-03-08 | Microwave Semiconductor Corporation | Semiconductor wafer dicing techniques |
US4964212A (en) * | 1988-09-29 | 1990-10-23 | Commissariat A L'energie Atomique | Process for producing electrical connections through a substrate |
US4851371A (en) * | 1988-12-05 | 1989-07-25 | Xerox Corporation | Fabricating process for large array semiconductive devices |
US4992393A (en) * | 1989-06-01 | 1991-02-12 | Ricoh Company, Ltd. | Method for producing semiconductor thin film by melt and recrystallization process |
US5385633A (en) * | 1990-03-29 | 1995-01-31 | The United States Of America As Represented By The Secretary Of The Navy | Method for laser-assisted silicon etching using halocarbon ambients |
US5185295A (en) * | 1990-05-16 | 1993-02-09 | Kabushiki Kaisha Toshiba | Method for dicing semiconductor substrates using a laser scribing and dual etch process |
US5214261A (en) * | 1990-09-10 | 1993-05-25 | Rockwell International Corporation | Method and apparatus for dicing semiconductor substrates using an excimer laser beam |
US5151389A (en) * | 1990-09-10 | 1992-09-29 | Rockwell International Corporation | Method for dicing semiconductor substrates using an excimer laser beam |
US5075201A (en) * | 1990-10-31 | 1991-12-24 | Grumman Aerospace Corporation | Method for aligning high density infrared detector arrays |
US5552345A (en) * | 1993-09-22 | 1996-09-03 | Harris Corporation | Die separation method for silicon on diamond circuit structures |
US5932118A (en) * | 1994-05-16 | 1999-08-03 | Sanyo Electric Co., Ltd. | Photoprocessing method |
US5631190A (en) * | 1994-10-07 | 1997-05-20 | Cree Research, Inc. | Method for producing high efficiency light-emitting diodes and resulting diode structures |
US5912477A (en) * | 1994-10-07 | 1999-06-15 | Cree Research, Inc. | High efficiency light emitting diodes |
US5543365A (en) * | 1994-12-02 | 1996-08-06 | Texas Instruments Incorporated | Wafer scribe technique using laser by forming polysilicon |
US5864171A (en) * | 1995-03-30 | 1999-01-26 | Kabushiki Kaisha Toshiba | Semiconductor optoelectric device and method of manufacturing the same |
US5916460A (en) * | 1995-07-07 | 1999-06-29 | Hitachi Cable, Ltd. | Method and apparatus for dicing a substrate |
US5641416A (en) * | 1995-10-25 | 1997-06-24 | Micron Display Technology, Inc. | Method for particulate-free energy beam cutting of a wafer of die assemblies |
US5922224A (en) * | 1996-02-09 | 1999-07-13 | U.S. Philips Corporation | Laser separation of semiconductor elements formed in a wafer of semiconductor material |
US5872046A (en) * | 1996-04-10 | 1999-02-16 | Texas Instruments Incorporated | Method of cleaning wafer after partial saw |
US6117347A (en) * | 1996-07-10 | 2000-09-12 | Nec Corporation | Method of separating wafers into individual die |
US5976691A (en) * | 1996-12-19 | 1999-11-02 | Lintec Corporation | Process for producing chip and pressure sensitive adhesive sheet for said process |
US6225194B1 (en) * | 1996-12-19 | 2001-05-01 | Lintec Corporation | Process for producing chip and pressure sensitive adhesive sheet for said process |
US6140151A (en) * | 1998-05-22 | 2000-10-31 | Micron Technology, Inc. | Semiconductor wafer processing method |
Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050263854A1 (en) * | 1998-10-23 | 2005-12-01 | Shelton Bryan S | Thick laser-scribed GaN-on-sapphire optoelectronic devices |
US20040224508A1 (en) * | 2003-05-06 | 2004-11-11 | Applied Materials Israel Ltd | Apparatus and method for cleaning a substrate using a homogenized and non-polarized radiation beam |
US20040253796A1 (en) * | 2003-06-10 | 2004-12-16 | Na Jeong Seok | Method for manufacturing gallium nitride (GaN) based single crystalline substrate |
US6902989B2 (en) * | 2003-06-10 | 2005-06-07 | Samsung Electro-Mechanics Co., Ltd. | Method for manufacturing gallium nitride (GaN) based single crystalline substrate that include separating from a growth substrate |
US7105859B2 (en) * | 2003-11-05 | 2006-09-12 | Sharp Kabushiki Kaisha | Nitride semiconductor light-emitting diode chip and method of manufacturing the same |
US20050093016A1 (en) * | 2003-11-05 | 2005-05-05 | Sharp Kabushiki Kaisha | Nitride semiconductor light-emitting diode chip and method of manufacturing the same |
CN100389485C (en) * | 2003-12-27 | 2008-05-21 | 上海华虹(集团)有限公司 | Method for producing integrated circuit sample section using laser |
US20050242073A1 (en) * | 2004-04-28 | 2005-11-03 | Disco Corporation | Laser beam processing method |
US20060030125A1 (en) * | 2004-08-04 | 2006-02-09 | Gelcore, Llc | Laser separation of encapsulated submount |
US7087463B2 (en) | 2004-08-04 | 2006-08-08 | Gelcore, Llc | Laser separation of encapsulated submount |
US20070004088A1 (en) * | 2004-08-04 | 2007-01-04 | Gelcore, Llc. | Laser separation of encapsulated submount |
US20060154390A1 (en) * | 2005-01-11 | 2006-07-13 | Tran Chuong A | Systems and methods for producing light emitting diode array |
US7378288B2 (en) * | 2005-01-11 | 2008-05-27 | Semileds Corporation | Systems and methods for producing light emitting diode array |
US7494898B2 (en) * | 2006-01-06 | 2009-02-24 | Shinko Electric Industries Co., Ltd. | Method for manufacturing semiconductor device |
US20070161211A1 (en) * | 2006-01-06 | 2007-07-12 | Masahiro Sunohara | Method for manufacturing semiconductor device |
US20070235430A1 (en) * | 2006-04-10 | 2007-10-11 | Disco Corporation | Laser beam processing machine |
US8610030B2 (en) * | 2006-04-10 | 2013-12-17 | Disco Corporation | Laser beam processing machine |
US20080237189A1 (en) * | 2007-03-30 | 2008-10-02 | Oc Oerlikon Balzers Ag | Method for laser scribing of solar panels |
US8299396B2 (en) * | 2007-03-30 | 2012-10-30 | Oerlikon Solar Ag, Trubbach | Method for laser scribing of solar panels |
US20100258539A1 (en) * | 2007-07-18 | 2010-10-14 | Hamamatsu Photonics K.K. | Machining information supply equipment and supply system |
US8436273B2 (en) * | 2007-07-18 | 2013-05-07 | Hamamatsu Photonics K.K. | Machining information supply equipment and supply system |
WO2015072598A1 (en) * | 2013-11-14 | 2015-05-21 | (주)정원기술 | Laser optic device for bonding flip chip by laser pressing |
CN113782654A (en) * | 2021-09-13 | 2021-12-10 | 錼创显示科技股份有限公司 | Light emitting diode structure and manufacturing method thereof |
TWI782703B (en) * | 2021-09-13 | 2022-11-01 | 錼創顯示科技股份有限公司 | Light-emitting diode structure and manufacturing method thereof |
US20230083176A1 (en) * | 2021-09-13 | 2023-03-16 | PlayNitride Display Co., Ltd. | Light-emitting diode structure and manufacturing method thereof |
WO2024006962A3 (en) * | 2022-06-30 | 2024-02-29 | University Of Virginia Patent Foundation | Use of lasers to selectively remove materials from substrates |
Also Published As
Publication number | Publication date |
---|---|
US20020127824A1 (en) | 2002-09-12 |
US20050003634A1 (en) | 2005-01-06 |
US6902990B2 (en) | 2005-06-07 |
US6849524B2 (en) | 2005-02-01 |
US20020177288A1 (en) | 2002-11-28 |
US6413839B1 (en) | 2002-07-02 |
TW521334B (en) | 2003-02-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20030003690A1 (en) | Semiconductor device separation using a patterned laser projection | |
KR100854986B1 (en) | Production method of compound semiconductor device wafer | |
US7008861B2 (en) | Semiconductor substrate assemblies and methods for preparing and dicing the same | |
CN1943050B (en) | compound semiconductor light-emitting device, wafer and production method of wafer | |
JP3449201B2 (en) | Method for manufacturing nitride semiconductor device | |
JP2006135309A (en) | Manufacturing method of semiconductor device | |
JP2005109432A (en) | Manufacturing method of group iii nitride-based compound semiconductor device | |
JP2765644B2 (en) | Gallium nitride based compound semiconductor wafer cutting method | |
JP2002329684A (en) | Nitride semiconductor chip and its manufacturing method | |
JP2748354B2 (en) | Method of manufacturing gallium nitride based compound semiconductor chip | |
JP2859478B2 (en) | Gallium nitride based compound semiconductor wafer cutting method for light emitting device | |
JPH06283758A (en) | Method of cutting gallium nitride compound semiconductor wafer | |
JP4244618B2 (en) | Method of manufacturing nitride semiconductor device | |
JP2005286098A (en) | Group iii nitride compound semiconductor element and its manufacturing method | |
Shelton et al. | Nitride LED chip separation technologies |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |
|
AS | Assignment |
Owner name: POWER INTEGRATIONS, INC., CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:VELOX SEMICONDUCTOR CORPORATION;REEL/FRAME:024927/0893 Effective date: 20100826 |