Granted Patent
Utility
US 4,728,869 · App. 06/845,212
Pulsewidth modulated pressure control system for chemical vapor deposition apparatus
Inventors:
Noel H. Johnson, Gary Elliott
Patented Case
View Patent ↗
Granted: Mar 1, 1988
Filed: Mar 27, 1986
Inventors
Noel H. Johnson
Gary Elliott
Assignee (at issue)
Anicon, 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.