abstract |
Mechanisms for forming source/drain (S/D) regions of field effect transistors (FETs) are provided. The mechanisms eliminate dislocations near gate corners and gate corner defects (GCDs), and maintain transistor performance. The mechanisms described involve using a post-deposition etch to remove residual dislocations near gate corners after a cyclic deposition and etching (CDE) process is used to fill a portion of the recess regions with an epitaxially grown silicon-containing material. The mechanisms described also minimize the growth of dislocations near gate corners during the CDE process. The remaining recess regions may be filled by another silicon-containing layer deposited by an epitaxial process without forming dislocations near gate corners. The embodiments described enable gate corners to be free of dislocation defects, preserve the device performance from degradation, and widen the process window of forming S/D regions without gate corner defects and chamber matching issues. |