Granted Patent
Utility
US 5,677,092 · App. 08/383,839
Process for fabricating phase shift mask and process of semiconductor integrated circuit device
Inventors:
Toshitsugu Takekuma, Haruo Ii, Kazuya Ito
Patented Case
View Patent ↗
Granted: Oct 14, 1997
Filed: Feb 6, 1995
Inventors
Toshitsugu Takekuma
Haruo Ii
Kazuya Ito
Assignees (at issue)
HITACHI, LTD.
Hitachi VLSI Engineering Corp.
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.