Granted Patent
Utility
US 6,271,531 · App. 09/363,886
Charged beam drawing apparatus and method thereof
Inventor:
Toshiya Yamaguchi
Patented Case
View Patent ↗
Granted: Aug 7, 2001
Filed: Jul 30, 1999
Inventor
Toshiya Yamaguchi
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.