Granted Patent
Utility
US 4,885,472 · App. 07/167,601
Silicon grid as a reference and calibration standard in a particle beam lithography system
Inventor:
Lydia J. Young
Patented Case
View Patent ↗
Granted: Dec 5, 1989
Filed: Mar 14, 1988
Inventor
Lydia J. Young
Assignee (at issue)
PerkinElmer, 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.