Granted Patent
Utility
US 4,967,248 · App. 07/181,136
Structure of semiconductor memory cell with trench-type capacitor
Inventor:
Toshiyuki Shimizu
Patented Case
View Patent ↗
Granted: Oct 30, 1990
Filed: Apr 13, 1988
Inventor
Toshiyuki Shimizu
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.