Methods are provided for low temperature, rapid baking to remove
impurities from a semiconductor surface prior to in-situ deposition.
Advantageously, a short, low temperature process consumes very little of
the thermal budget, such that the process is suitable for advanced, high
density circuits with shallow junctions. Furthermore, throughput is
greatly improved by the low temperature bake, particularly in combination
with low temperature plasma cleaning and low temperature wafer loading
prior to the bake, and deposition after the bake at temperatures lower
than conventional epitaxial deposition. The process enables epitaxial
deposition of silicon-containing layers over semiconductor surfaces,
particularly enabling epitaxial deposition over a silicon germanium base
layer. By use of a low-temperature bake, the silicon germanium base layer
can be cleaned to facilitate further epitaxial deposition without
relaxing the strained crystal structure of the silicon germanium.