Semiconductor devices and methods of forming

Abstract

A method includes forming a fin structure that protrudes above a substrate; forming a source / drain opening in the fin structure adjacent to the gate structure; and forming a source / drain region in the source / drain opening. Forming the source / drain region comprises forming a first doped epitaxial material in the source / drain opening, wherein the first doped epitaxial material comprises a first semiconductor material doped with a first dopant; after forming the first doped epitaxial material, removing a portion of the first doped epitaxial material to form a cavity in the first doped epitaxial material; and forming a second doped epitaxial material in the cavity, wherein the second doped epitaxial material comprises the first semiconductor material doped with the first dopant, wherein a second concentration of the first dopant in the second doped epitaxial material is higher than a first concentration of the first dopant in the first doped epitaxial material.