Granted Patent
Utility
US 4,889,588 · App. 07/345,795
Plasma etch isotropy control
Inventor:
Gianni O. Fior
Patented Case
View Patent ↗
Granted: Dec 26, 1989
Filed: May 1, 1989
Inventor
Gianni O. Fior
Assignee (at issue)
TEGAL 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.