Granted Patent
Utility
US 5,159,421 · App. 07/722,709
Double channel heterostructures
Inventor:
Peter Wolff
Patented Case
View Patent ↗
Granted: Oct 27, 1992
Filed: Jun 28, 1991
Inventor
Peter Wolff
Assignee (at issue)
NEC Research Institute, 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.