SEMICONDUCTOR DEVICES UTILIZING PARTIALLY DOPED STRESSOR FILM PORTIONS

摘要

A method includes providing a gate structure over a semiconductor substrate and forming a source/drain region associated with the gate structure by etching an opening in the semiconductor substrate, performing a first epitaxial growth process while an entirety of a sidewall of the opening is exposed to grow a first epitaxy material in the opening. The first epitaxial growth process is free of a first dopant impurity. A second epitaxial growth process is performed after first epitaxial growth process to grow a second epitaxy material on the first epitaxy material. The second epitaxy material has the first dopant impurity at a first concentration. Further, a third epitaxial growth process is performed after the second epitaxial growth process that includes introducing the first dopant impurity at a second concentration, the second concentration greater than the first concentration.

主权项

1. A method of fabricating a semiconductor device, comprising:
providing a gate structure over a semiconductor substrate; forming a source/drain region associated with the gate structure, wherein the forming the source/drain region includes:
etching an opening in the semiconductor substrate adjacent the gate structure, wherein the opening provides a sidewall extending from a bottom surface of the opening to a top surface of the semiconductor substrate;performing a first epitaxial growth process while an entirety of the sidewall of the opening is exposed to grow a first epitaxy material in the opening, wherein the first epitaxial growth process is free of a first dopant impurity;performing a second epitaxial growth process after first epitaxial growth process to grow a second epitaxy material on the first epitaxy material, wherein the second epitaxial growth process includes introducing the first dopant impurity at a first concentration; andperforming a third epitaxial growth process after the second epitaxial growth process to grow a third epitaxy material on the second epitaxy material, wherein the third epitaxial growth process includes introducing the first dopant impurity at a second concentration, the second concentration greater than the first concentration.