Granted Patent
Utility
US 6,435,474 · App. 09/608,304
Non-contaminating gas-tight valve for semiconductor applications
Inventors:
Dick S. Williams, Treaf Andrus, Timothy J. Kulage, Ken Harrell
Patented Case
View Patent ↗
Granted: Aug 20, 2002
Filed: Jun 30, 2000
Inventors
Dick S. Williams
Treaf Andrus
Timothy J. Kulage
Ken Harrell
Assignee (at issue)
MEMC Electronic Materials, 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.