Granted Patent
Utility
US 4,832,496 · App. 06/925,485
Method and apparatus for measuring the monocrystal diameter and the melt level during crucible drawing in the Czochralski process
Inventor:
Friedrich-Werner Thomas
Patented Case
View Patent ↗
Granted: May 23, 1989
Filed: Oct 29, 1986
Inventor
Friedrich-Werner Thomas
Assignee (at issue)
Leybold-Heraeus GmbH
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.