Patent ID: 10991630

Abstract:
In an embodiment, a method includes: forming a first gate stack and a second gate stack on a fin; etching the fin to form a recess in the fin between the first gate stack and the second gate stack; forming an epitaxial source/drain region in the recess, the forming including: forming a first layer lining sides and a bottom of the recess by dispensing silane, dichlorosilane, trichlorosilane, and hydrochloric acid in the recess; and after forming the first layer, forming a second layer on the first layer by dispensing the silane, dichlorosilane, trichlorosilane, and hydrochloric acid in the recess, where each of the silane, dichlorosilane, trichlorosilane, and hydrochloric acid are dispensed at a first flow rate when forming the first layer and at a second flow rate when forming the second layer.