US Patent 11164944 Method of manufacturing a semiconductor device

A semiconductor device having an improved source/drain region profile and a method for forming the same are disclosed. In an embodiment, a method includes etching a semiconductor fin to form a first recess; and forming a source/drain region in the first recess, forming the source/drain region including epitaxially growing a first semiconductor material in the first recess, the first semiconductor material being silicon; epitaxially growing a second semiconductor material over the first semiconductor material, the second semiconductor material including silicon germanium; and epitaxially growing a third semiconductor material over the second semiconductor material, and the third semiconductor material having a germanium concentration from 60 to 80 atomic percent, the third semiconductor material having a germanium concentration greater than the germanium concentration of the second semiconductor material.