Abstract: 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.

Abstract: 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.

Abstract: A semiconductor structure and method for forming the same provide a high mobility stressor material suitable for use as source/drain regions or other active devices. The structure is formed in a substrate opening and is doped with an impurity such as boron in upper portions but is void of the impurity in regions that contact the surfaces of the opening. The structure is therefore resistant to out-diffusion of the dopant impurity during high temperature operations and may be formed through selective deposition using reduced pressure chemical vapor deposition or reduced pressure epitaxial deposition.

Abstract: A semiconductor structure and method for forming the same provide a high mobility stressor material suitable for use as source/drain regions or other active devices. The structure is formed in a substrate opening and is doped with an impurity such as boron in upper portions but is void of the impurity in regions that contact the surfaces of the opening. The structure is therefore resistant to out-diffusion of the dopant impurity during high temperature operations and may be formed through selective deposition using reduced pressure chemical vapor deposition or reduced pressure epitaxial deposition.