Granted Patent
Utility
US 6,749,974 · App. 10/234,790
Disposable hard mask for photomask plasma etching
Inventor:
David Chan
Patented Case
View Patent ↗
Granted: Jun 15, 2004
Filed: Sep 3, 2002
Inventor
David Chan
Assignee (at issue)
PHOTRONICS, 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.