Granted Patent
Utility
US 4,496,423 · App. 06/550,801
Gas feed for reactive ion etch system
Inventor:
Frank J. Walton
Patented Case
View Patent ↗
Granted: Jan 29, 1985
Filed: Nov 14, 1983
Inventor
Frank J. Walton
Assignee (at issue)
GCA 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.