US Patent 12119401 Semiconductor device and methods of forming

In an embodiment, a device includes a first fin extending from a substrate. The device also includes a first gate stack over and along sidewalls of the first fin. The device also includes a first gate spacer disposed along a sidewall of the first gate stack. The device also includes and a first source/drain region in the first fin and adjacent the first gate spacer, the first source/drain region including a first epitaxial layer on the first fin, the first epitaxial layer having a first dopant concentration of boron. The device also includes and a second epitaxial layer on the first epitaxial layer, the second epitaxial layer having a second dopant concentration of boron, the second dopant concentration being greater than the first dopant concentration.