DE3619342A1 - Internal coating, internal alloying, internal filling of through-holes using a laser - Google Patents

Internal coating, internal alloying, internal filling of through-holes using a laser

Info

Publication number
DE3619342A1
DE3619342A1 DE19863619342 DE3619342A DE3619342A1 DE 3619342 A1 DE3619342 A1 DE 3619342A1 DE 19863619342 DE19863619342 DE 19863619342 DE 3619342 A DE3619342 A DE 3619342A DE 3619342 A1 DE3619342 A1 DE 3619342A1
Authority
DE
Germany
Prior art keywords
internal
workpiece
coating
laser beam
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.)
Withdrawn
Application number
DE19863619342
Other languages
German (de)
Inventor
Klaus Dr Rohr
Rudolf Thoemmes
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to DE19863619342 priority Critical patent/DE3619342A1/en
Publication of DE3619342A1 publication Critical patent/DE3619342A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
    • H05K3/4038—Through-connections; Vertical interconnect access [VIA] connections
    • H05K3/4076—Through-connections; Vertical interconnect access [VIA] connections by thin-film techniques
    • 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
    • B23K26/38—Removing material by boring or cutting
    • B23K26/382—Removing material by boring or cutting by boring
    • 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
    • B23K26/38—Removing material by boring or cutting
    • B23K26/382—Removing material by boring or cutting by boring
    • B23K26/389—Removing material by boring or cutting by boring of fluid openings, e.g. nozzles, jets
    • 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
    • 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
    • B23K2101/34—Coated articles, e.g. plated or painted; Surface treated articles
    • 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
    • B23K2103/08—Non-ferrous metals or alloys
    • B23K2103/10—Aluminium or alloys thereof
    • 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
    • B23K2103/08—Non-ferrous metals or alloys
    • B23K2103/12—Copper or alloys thereof
    • 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
    • B23K2103/16—Composite materials, e.g. fibre reinforced
    • B23K2103/166—Multilayered materials
    • B23K2103/172—Multilayered materials wherein at least one of the layers is non-metallic
    • 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
    • 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
    • B23K2103/52—Ceramics

Abstract

The method represents a universal method with which a laser can be used to coat or fill through-holes in a workpiece with another material. Using the method, the procedure adopted can be in particular such that (Fig. 1) the laser (1) produces the hole to be coated in the workpiece (2) in one operation and, after the undercut coating material (4, 5) is reached, it is expelled and becomes deposited (3) on the inner wall of the tool. Advantages of the method are that: 1. virtually any desired combinations of workpiece and coating material are possible, 2. only small thermal stresses occur and 3. high repetition rates and an easy-to-control processing pattern are possible. The following ranges of application are suitable: through-contacting microcircuits and local processing of for example films for increasing the mechanical, chemical or biological resistance. <IMAGE>

Description

Die Erfindung betrifft ein Verfahren zur Innenbeschich­ tung, Innenlegierung oder Innenfüllung von Durchgangs­ löchern mit Hilfe des Lasers. Hierbei besteht die Mög­ lichkeit, Löcher im gleichen Arbeitsgang mit dem Laser zu bohren und innen zu beschichten. Das Verfahren eignet sich vor allem für kleine Lochdurchmesser (Submillime­ terbereich) entsprechend dem bekannten Anwendungsspek­ trum des Laserbohrens. The invention relates to a method for internal coating processing, interior alloy or interior filling of passage holes with the help of the laser. Here is the possibility holes in the same operation with the laser to drill and coat inside. The procedure is suitable especially for small hole diameters (submillimes terbereich) according to the known application spec of laser drilling.  

Zum Innenbeschichten von Löchern werden bisher vielfach Methoden benutzt, wie das thermische Einschmelzen (z. B. beim Durchkontaktieren elektrischer Mikroschaltkreise), das Eindiffundieren oder das Bedampfen.So far, many have been used for coating holes on the inside Used methods such as thermal melting (e.g. when through-contacting electrical microcircuits), diffusing or vapor deposition.

Diese Methoden belasten thermisch oder chemisch das Werkstück insgesamt, sie sind nur für eine begrenzte Zahl von Stoffkombinationen des zu beschichtenden und des Beschichtungsmaterials prinzipiell verwendbar oder der Wirkungseffekt ist gering (z. B. beim Aufdampfen in dünne Kanäle).These methods put a thermal or chemical strain on this Workpiece total, they are limited only Number of combinations of substances to be coated and the coating material can be used in principle or the effect is low (e.g. when vapor deposition into thin channels).

Der Erfindung liegt die Aufgabe zugrunde eine schnelle, steuerbare, werkstückschonende und bezüglich des Ma­ terials universelle Methode zur Innenbeschichtung von Löchern bereitzustellen.The invention has for its object a quick, controllable, gentle on the workpiece and with respect to the Ma terials universal method for the interior coating of To provide holes.

Die Aufgabe wird erfindungsgemäß dadurch gelöst, daß zum Verdampfen des Beschichtungsmaterials ein Laser benutzt wird, und daß dieser Laser vorteilhaft im glei­ chen Arbeitsgang zum vorherigen Bohren der Löcher ein­ gesetzt werden kann. Dadurch beinhaltet das Verfahren positive Eigenschaften, die bereits vom Laserbohren und der Lasermaterialbearbeitung allein bekannt sind.The object is achieved in that a laser to evaporate the coating material is used, and that this laser is advantageous in the same operation to drill the holes beforehand can be set. As a result, the process includes positive properties already from laser drilling and laser material processing alone are known.

Die Hauptvorteile des Verfahrens sind:The main advantages of the process are:

  • a) es ist sehr schnell, Repititionsraten bis in den kHz- Bereich sind möglich.a) it is very fast to repeat rates up to the kHz Range are possible.
  • b) das Bearbeitungsraster ist computersteuerbar.b) the processing grid is computer-controlled.
  • c) das Werkstück wird thermisch nur in einem Bereich von der Größe des Loches belastet, dadurch können wärmeempfindliche Komponenten auch mit hochschmel­ zenden Stoffen beschichtet werden.c) the workpiece is thermally only in one area burdened by the size of the hole, this can  heat sensitive components also with high melting point fabrics are coated.
  • d) es können Löcher in Materialien mit extremen, phy­ sikalischen oder chemischen Eigenschaften beschichtet werden.d) holes in materials with extreme, phy sical or chemical properties coated will.
  • e) es können gegebenenfalls unter Benutzung von har­ monisierenden Zwischenschichten beliebige Stoffe ein­ gebracht werden, um bestimmte Wirkungen zu opti­ mieren: z. B. elektrisch oder thermisch hochleitende Stoffe bei elektronischen Bauteilen; chemisch oder biologisch resistente Stoffe etwa zur lokalen Verede­ lung oder zum Schutz (Holzschutz), physikalisch harte Stoffe zur Erhöhung der Abriebfestigkeit.e) if necessary using har monizing intermediate layers any substances brought to opti certain effects Mieren: z. B. electrically or thermally highly conductive Fabrics for electronic components; chemical or biologically resistant substances, for example for local consumption or for protection (wood protection), physically hard Fabrics to increase abrasion resistance.
  • f) Variationen des Lasers ermöglichen wahlweises Auf­ dampfen, Auflegieren oder Innenfüllen eines geome­ trisch wählbaren Loches.f) Variations in the laser enable optional opening steaming, alloying or filling a geome selectable hole.

Das Prinzip des Verfahrens ist in Abb. 1 darge­ stellt. Ein geeignet dimensionierter Laserstrahl (1) durchbohrt das Werkstück (2), wobei das Erruptionsgut (3) in Gegenrichtung zum Laserstrahl (1) herausgeschleu­ dert wird. Anschließend trifft der Laserstrahl auf die (dünne) harmonisierende Zwischenschicht (4) und auf das aufzudampfende Material (5). Je nach dessen physika­ lischen Eigenschaften und Wahl der Laserparameter (z. B. zeitliche Pulsform, Energie, Wellenlänge) bildet sich plasmaförmiges, dampfförmiges oder flüssiges Be­ schichtungsgut (im letzten Fall ist eine temperaturab­ hängige Einstellung der Viskosität möglich) welches ebenfalls in Gegenrichtung zum Laserstrahl ausgetrieben wird. Dieses kann in der gewünschten Wandstärke im Bohrkanal zum Niederschlagen, Erstarren oder unter Ausnutzung der harmonisierenden Schicht zum Auflegieren gebracht werden. The principle of the process is shown in Fig. 1 Darge. A suitably dimensioned laser beam ( 1 ) pierces the workpiece ( 2 ), the material to be erupted ( 3 ) being ejected in the opposite direction to the laser beam ( 1 ). The laser beam then strikes the (thin) harmonizing intermediate layer ( 4 ) and the material to be vapor-deposited ( 5 ). Depending on its physical properties and choice of laser parameters (e.g. temporal pulse shape, energy, wavelength), plasma-shaped, vaporous or liquid coating material is formed (in the latter case, a temperature-dependent adjustment of the viscosity is possible), which is also in the opposite direction to the laser beam is driven out. This can be made to precipitate, solidify, or use the harmonizing layer to alloy it in the desired wall thickness in the drill channel.

Abb. 2 zeigt die Elektronenmikroskopaufnahme eines Loches (⌀0,2 mm) in einer Al2O3 Keramikscheibe (Dicke 0,7 mm), welches mit einem ersten Laserpuls gebohrt wur­ de. Die Laserparameter sind hierbei so eingestellt, daß das Beschichtungsmaterial noch nicht erreicht wurde. Bei einem zweiten, unmittelbar folgenden Laserpuls wird Erruptionsgut der harmonisierenden Zwischenschicht (hier Alu-Folie, 0,05 mm Dicke) und des Bedampfungsguts (hier Cu-Blech) in die Bohrung gedrückt und erstarrt dort. Das Ergebnis ist in Abb. 3 wiedergegeben. Durch die Einbringung des Kupfers hat sich der ursprüngliche Lochdurchmesser um ca. 20% verringert. Fig. 2 shows the electron micrograph of a hole (⌀0.2 mm) in an Al 2 O 3 ceramic disc (thickness 0.7 mm), which was drilled with a first laser pulse. The laser parameters are set so that the coating material has not yet been reached. In the case of a second, immediately following laser pulse, the eruption material of the harmonizing intermediate layer (here aluminum foil, 0.05 mm thick) and the material to be vaporized (here copper sheet) is pressed into the bore and solidifies there. The result is shown in Fig. 3. By introducing the copper, the original hole diameter has been reduced by approx. 20%.

Als Laser diente im vorliegenden Fall ein gepulstes Nd- Glas-System im Spiking-Betrieb (Multimode, Wellenlänge 1,06 µm, Pulslänge ca. 100 µs). Die Energie lag bei etwa 1 Joule.In the present case, a pulsed Nd- Glass system in spiking mode (multimode, wavelength 1.06 µm, pulse length approx. 100 µs). The energy was about 1 joule.

Claims (4)

1. Verfahren zum Innenbeschichten, Innenlegieren und/oder Innenfüllen von Durchgangslöchern in Werkstücken mit Hilfe eines Laserstrahles, insbesondere zur elektrischen Durchkontaktierung, zum Innenlegieren oder Innenfüllen von Mikrobohrungen, dadurch gekennzeichnet, daß das zum Beschichten, Le­ gieren und/oder Füllen dienende Material (im folgenden zur Abkürzung als Beschichtungsmaterial bezeichnet) an der Rückseite des Werkstückes angebracht ist, das Werkstück von einem Laserstrahl durchbohrt wird, wonach das Beschichtungsmaterial, sobald es vom Laserstrahl erreicht wird, im plasmaförmigen, dampfförmigen und/oder flüssigen Zustand, entgegen dem Laserstrahl in das gebohrte Loch eindringt und dort erstarrt.1. A method for the internal coating, internal alloying and / or filling of through holes in workpieces with the aid of a laser beam, in particular for electrical through-plating, for internal alloying or internal filling of micro bores, characterized in that the material used for coating, alloying and / or filling (in hereinafter referred to for short as coating material) is attached to the back of the workpiece, the workpiece is pierced by a laser beam, after which the coating material, as soon as it is reached by the laser beam, in the plasma-shaped, vaporous and / or liquid state, counter to the laser beam into the drilled Hole penetrates and solidifies there. 2. Verfahren nach Anspruch 1 zum Innenbeschichten, Innen­ legieren und/oder Innenfüllen eines vorhandenen Loches in einem Werkstück, dadurch gekennzeichnet, daß ein Laserstrahl durch das Loch fokussiert wird und auf das Beschichtungsmaterial einwirkt, welches auf der Rückseite angebracht ist. 2. The method according to claim 1 for internal coating, indoor alloy and / or fill an existing hole in a workpiece, characterized in that a laser beam through the Hole is focused and on the coating material acts, which is attached to the back.   3. Verfahren nach Anspruch 1 und 2 zum Beschichten oder Legieren von offenen Konturen eines Werkstückes, dadurch gekennzeichnet, daß der Laserstrahl bzw. bei ortsfestem Laserstrahl das Werkstück entlang der je­ weiligen Kontur geführt wird.3. The method according to claim 1 and 2 for coating or Alloying open contours of a workpiece, characterized in that the laser beam or at stationary laser beam along the workpiece due contour is performed. 4. Verfahren nach Anspruch 1, 2 und 3, dadurch gekennzeichnet, daß zwischen Rückseite des Werkstückes und Beschichtungsmaterial mindestens eine das Verfahren begünstigende Zwischenschicht angebracht ist.4. The method according to claim 1, 2 and 3, characterized in that between the back of the Workpiece and coating material at least one intermediate layer favoring the process is.
DE19863619342 1986-06-09 1986-06-09 Internal coating, internal alloying, internal filling of through-holes using a laser Withdrawn DE3619342A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19863619342 DE3619342A1 (en) 1986-06-09 1986-06-09 Internal coating, internal alloying, internal filling of through-holes using a laser

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19863619342 DE3619342A1 (en) 1986-06-09 1986-06-09 Internal coating, internal alloying, internal filling of through-holes using a laser

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DE3619342A1 true DE3619342A1 (en) 1987-12-10

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5498850A (en) * 1992-09-11 1996-03-12 Philip Morris Incorporated Semiconductor electrical heater and method for making same
WO1996012830A1 (en) * 1994-10-20 1996-05-02 Electro Scientific Industries, Inc. Laser method for plating vias
US5593606A (en) * 1994-07-18 1997-01-14 Electro Scientific Industries, Inc. Ultraviolet laser system and method for forming vias in multi-layered targets
WO2002029845A2 (en) * 2000-10-04 2002-04-11 Plasmion Displays, Llc Method of fabricating plasma display panel using laser process
WO2009059752A2 (en) * 2007-11-07 2009-05-14 Solarion Ag Method and means for connecting thin metal layers
DE102018215069A1 (en) * 2018-09-05 2020-03-05 Robert Bosch Gmbh Method for connecting individual film-shaped foils of a battery foil stack

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5498850A (en) * 1992-09-11 1996-03-12 Philip Morris Incorporated Semiconductor electrical heater and method for making same
US5659656A (en) * 1992-09-11 1997-08-19 Philip Morris Incorporated Semiconductor electrical heater and method for making same
US5593606A (en) * 1994-07-18 1997-01-14 Electro Scientific Industries, Inc. Ultraviolet laser system and method for forming vias in multi-layered targets
US5614114A (en) * 1994-07-18 1997-03-25 Electro Scientific Industries, Inc. Laser system and method for plating vias
WO1996012830A1 (en) * 1994-10-20 1996-05-02 Electro Scientific Industries, Inc. Laser method for plating vias
DE19581659T1 (en) * 1994-10-20 1997-05-22 Electro Scient Ind Inc Storage system and method for metallizing passageways
WO2002029845A2 (en) * 2000-10-04 2002-04-11 Plasmion Displays, Llc Method of fabricating plasma display panel using laser process
WO2002029845A3 (en) * 2000-10-04 2003-04-17 Plasmion Displays Llc Method of fabricating plasma display panel using laser process
WO2009059752A2 (en) * 2007-11-07 2009-05-14 Solarion Ag Method and means for connecting thin metal layers
WO2009059752A3 (en) * 2007-11-07 2009-12-03 Solarion Ag Method and means for connecting thin metal layers
DE102018215069A1 (en) * 2018-09-05 2020-03-05 Robert Bosch Gmbh Method for connecting individual film-shaped foils of a battery foil stack

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