United States Patent 6,054,333
Real time etch measurements and control using isotopes
Abstract
A method is provided for determining etching characteristics
during gas phase etching of thin film materials such as semiconductors
during manufacture of devices. Etch end point, rate of etching,
uniformity of etching and uniformity of growth of thin films can be
determined. Isotopically enriched materials are deposited in layers
which may be only a few nanometers thick at selected locations during
growth of the thin films. The isotopes are removed during gas phase
etching, carried by gas into an analysis chamber, condensed on a
surface, and analyzed for isotopical composition. Mass spectroscopy
of recoiled ions is a preferred detection technique.
Inventors:
Bensaoula, Abdelhak (Houston, TX)
Assignee:
University of Houston (Houston, TX)
Appl. No.:
950344
Filed:
14 Oct 1997