The effect of adsorbed atomic hydrogen on the growth of ultrathin silicon films on Ge(100) studied by positron-annihilation-induced Auger electron spectroscopy (PAES)

The effects of adsorbed atomic hydrogen on the stability of silicon films grown on a Ge(100) substrate were studied by using positron-annihilation-induced Auger electron spectroscopy (PAES) and electron-induced Auger electron spectroscopy (EAES). PAES is almost exclusively sensitive to the topmost atomic layer due to the trapping of positrons in an image potential well just outside the surface before annihilation. This surface specificity was exploited in the study of film stability and interfacial mixing during the growth of silicon on Ge(100). The PAES results show that the prior adsorption of hydrogen prevented the segregation of germanium on top of the deposited silicon, and that the hydrogen adsorption was useful in growing a thermally stable structure.