Granted Patent
Utility
US 6,494,221 · App. 09/442,190
Device for wet etching an edge of a semiconductor disk
Inventors:
Reinhard Sellmer, Robert KUMNIG
Patented Case
View Patent ↗
Granted: Dec 17, 2002
Filed: Nov 16, 1999
Inventors
Reinhard Sellmer
Robert KUMNIG
Assignee (at issue)
SEZ AG
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.