Semiconductor device source/drain region with arsenic-containing barrier region

A method of manufacturing a semiconductor device, the method comprising:

• etching a recess in a fin proximate a gate structure, the gate structure being on the fin on a substrate;
• forming a barrier region along a bottom surface and side surface of the recess, the barrier region comprising arsenic;
• and
• epitaxially growing an epitaxial material on the barrier region, the epitaxial material comprising phosphorous.

A method of manufacturing a semiconductor device, the method comprising:

• forming a first gate structure over a first semiconductor fin;
• forming a first recess and a second recess in the first semiconductor fin on opposing sides of the first gate structure;
• forming a barrier region along a bottom surface and side surface of the first recess and the second recess, the barrier region comprising arsenic;
• and
• epitaxially growing an epitaxial material on the barrier region, the epitaxial material comprising an n-type dopant.