Adsorption of Disilyne [Si(H[sub 2])Si] and Disilene (H[sub 2]SiSiH[sub 2]) on the Si(100)-2×1 Surface and on the H-Terminated Si(100)-2×1 Surface

Abstract

Disilyne [Si (H2) Si] and disilene (H2 SiSiH2) adsorption on the Si (100) -2?1 surface and the H-terminated Si (100) -2?1 surface was investigated by density functional theory calculations using the Si9 H12 and Si9 H14 cluster models of the surface. It was found that on the Si (100) -2?1 surface, a positive activation energy does not exist for the adsorptions of both disilyne and disilene. On the H-terminated Si (100) -2?1 surface, disilyne adsorbs through a positive activation energy around 10.9-14.7 kcal mol-1 at the Becke-3 Lee-Yang-Parr functional and the 6-31G(d) basis set level. No stable disilene adsorption structure on the H-terminated Si (100) -2?1 surface was found, which indicates that disilene rarely reacts with the H-terminated Si (100) -2?1 surface. For the adsorption of disilyne on the H-terminated Si (100) -2?1 surface, the adsorption energy calculated using the Si41 H42 cluster model (24.8 kcal mol-1) is in reasonable agreement with that calculated using the Si9 H14 cluster model (25.3 kcal mol-1). ? 2008 The Electrochemical Society.