Granted Patent
Utility
US 5,998,797 · App. 09/060,078
Mask for electron beam exposure and electron beam drawing method
Inventor:
Ken Nakajima
Patented Case
View Patent ↗
Granted: Dec 7, 1999
Filed: Apr 15, 1998
Inventor
Ken Nakajima
Assignee (at issue)
NEC CORPORATION
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.