Adsorption studies of digermane and disilane on Ge(100)

Abstract

Adsorption studies of digermane (Ge2H6) and disilane (Si2H6) on Ge(100) are reported. Temperature‐programmed desorption (TPD) experiments suggest the existence of two hydrogen adsorption states in the submonolayer regime for both digermane and disilane. The TPD spectra observed for disilane on Ge(100) are qualitatively similar to previous studies of disilane adsorbed on thin epitaxial layers of germanium on Si(100). These spectra show the existence of an α‐state arising from the germanium monohydride and a β1‐state arising from a silicon monohydride. The two‐peak structure observed in the hydrogen TPD spectra for digermane on Ge(100) suggests the existence of both germanium monohydride and germanium dihydride, about which there is disagreement in the literature. However, high‐resolution electron energy‐loss spectroscopy and low‐energy electron diffraction provide additional evidence for the existence of both germanium hydrides on the digermane/Ge(100) system. Kinetic energy distributions of electronically desorbed H+ and hydrogen removal cross‐sections obtained through electron‐stimulated desorption are also presented for both systems. Copyright © 2000 John Wiley & Sons, Ltd.

NO adsorption on Ge(1 0 0) studied by TPD

“…This study used an ultra-high vacuum system which has been described in detail elsewhere [4,5]. Additional details and drawings may be found in several Ph.D.…”

XPS study of electron‐induced surface processes in trimethylsilane‐covered Ge(100) surfaces

“…Total cross-sections for electron-induced processes on surfaces typically vary over several orders of magnitude from 10 20 to 10 16 cm 2 , depending upon the adsorption system. For example, Ateca et al 11 for disilane on Ge(100) found total cross-sections for hydrogen removal to be ¾3 ð 10 17 cm 2 .…”

“…This type of nucleation of silicon on the Ge(100) surface has been observed previously for disilane adsorption. 11 Three-dimensional island growth would result in shrinkage of the surface area occupied by silicon, resulting in an apparent decrease in Si-Si bond concentration. The trends shown in Fig.…”

“…3 Previous AFM studies of disilane-dosed Ge(100) have shown the formation of Si islands. 11 Even though we have not done AFM studies on this system, it is certainly reasonable to assume that silicon aggregates/islands are formed with the TMSiH adsorbate as well. Consequently, even with the occurrence of silicon islanding, the trends shown in the relative carbon and silicon signals are reasonable.…”

Dimerization of NO and transformation to N2O on Ge()

“…This study used an ultra-high vacuum system which has been described in detail elsewhere [32,33]. Additional details and drawings may be found in several Ph.D.…”