Patent · US Active

Exposure control for phase shifting photolithographic masks

US7629109B2 · kind B2 · utility

0Cited by
59References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 7, 2008
Grant dateDec 8, 2009
Priority date—
Expiry dateApr 7, 2028

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70558
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

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 the same exposure conditions. These approaches facilitate better exposure profiles for the resulting ICs and can thus improve chip yield and increase throughput by reducing the need to alter settings and/or switch reticles between exposures.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.