Granted Patent
Utility
US 6,218,681 · App. 09/220,446
Gallium arsenide phosphide epitaxial wafer and light emitting diode
Inventor:
Tadashige Sato
Patented Case
View Patent ↗
Granted: Apr 17, 2001
Filed: Dec 24, 1998
Inventor
Tadashige Sato
Assignee (at issue)
MITSUBISHI CHEMICAL 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.