Granted Patent
Utility
US 6,797,441 · App. 10/294,253
Method and apparatus for using a complementary mask to clear phase conflicts on a phase shifting mask
Inventor:
Christophe Pierrat
Patented Case
View Patent ↗
Granted: Sep 28, 2004
Filed: Nov 14, 2002
Inventor
Christophe Pierrat
Assignee (at issue)
Numerical Technologies, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.