Granted Patent
Utility
US 6,042,972 · App. 09/098,785
Phase shift mask having multiple alignment indications and method of manufacture
Inventor:
Steffen Schulze
Patented Case
View Patent ↗
Granted: Mar 28, 2000
Filed: Jun 17, 1998
Inventor
Steffen Schulze
Assignee (at issue)
Siemens Aktiengesellschaft
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.