V-Shaped Dislocation Prevention by Selective SiGe Epitaxy Process Tuning

Dislocation is an important factor affecting the stress of SiGe epitaxial films. Besides being related to the surface treatment of the previous process, the parameter control of the epitaxial process is crucial for dislocations. Currently, V-shaped dislocation defects have appeared in the 28nm PMOS embedded source drain SiGe epitaxial films. Unlike other dislocations, this type of dislocation can cause sunken phenomenon in high germanium concentration film and having a risk of device failure. This article studies the causes and solutions of dislocations from the perspective of process recipe design.