C incorporation mechanisms on Si(001) investigated by ab initio calculations

Substitutional C in Si or SiGe alloys is desirable for heterobipolar transi stors. How to incorporate C substitutionally during film deposition and gro wth is critical and has been the subject of much experimental research. In this paper we describe a recent development in understanding C incorporatio n mechanisms on Si using ab initio calculations at the atomic level. Both s ubstitutional and interstitial incorporation mechanisms were elucidated bas ed on the results of C adsorption and diffusion on the Si(001) surface and subsurface. Favorable deposition and growth conditions were predicted and a re consistent with the findings of several experimental groups.