Discontinuity prevention for SiGe deposition

摘要

The present disclosure provides a process for producing a SiGe layer in a bipolar device having a reduced amount of gaps or discontinuities on a shallow trench isolation (STI) region use for a base electrode connection. The process is used for forming an SiGe layer for use in a semiconductor device. The process includes doping a single crystal substrate with a first dopant type, baking the doped single crystal substrate at a temperature less than 900° C., and at a pressure less than 100 torr; and depositing the SiGe layer on the baked single crystal substrate (epi SiGe) to serve as the base electrode and on the STI region (poly SiGe) to serve as a connection for the base electrode. The semiconductor device is thereby created from the combination of the doped single crystal substrate and the deposited SiGe layer.