Fin sculpting and cladding during replacement gate process for transistor channel applications

Abstract

Techniques are disclosed for sculpting and cladding the channel region of fins on a semiconductor substrate during a replacement gate process (e.g., for transistor channel applications). The sculpting and cladding can be performed when the channel region of the fins are re-exposed after the dummy gate used in the replacement gate process is removed. The sculpting includes performing a trim etch on the re-exposed channel region of the fins to narrow a width of the fins (e.g., by 2-6 nm). A cladding layer, which may include germanium (Ge) or silicon germanium (SiGe), can then be deposited on the trimmed fins, leaving the source/drain regions of the fins unaffected. The sculpting and cladding may be performed in-situ or without air break to increase the quality of the trimmed fins (e.g., as compared to an ex-situ process).