Mask and integrated circuit fabrication approaches are described to facilitate use of so called “full phase” masks. This facilitates use of masks where substantially all of a layout is defined using phase shifting. In one embodiment, the phase shifting mask and the trim mask are exposed using substantially...http://www.google.de/patents/US7629109?utm_source=gb-gplus-sharePatent US7629109 - Exposure control for phase shifting photolithographic masks
