Granted Patent
Utility
US 4,642,672 · App. 06/531,569
Semiconductor device having registration mark for electron beam exposure
Inventor:
Makoto Kitakata
Patented Case
View Patent ↗
Granted: Feb 10, 1987
Filed: Sep 13, 1983
Inventor
Makoto Kitakata
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.