Granted Patent
Utility
US 6,031,291 · App. 08/550,159
Common contact hole structure in semiconductor device
Inventors:
Norifumi Sato, Takami Hiruma, Hitoshi Mitani, Hidetaka Natsume
Patented Case
View Patent ↗
Granted: Feb 29, 2000
Filed: Oct 30, 1995
Inventors
Norifumi Sato
Takami Hiruma
Hitoshi Mitani
Hidetaka Natsume
Assignee (at issue)
NEC 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.