In this study, the initial growth characteristics of a SiGe film realized by ultrahigh-vacuum chemical vapor deposition (UHV CVD) using GeH{sub}4 and Si{sub}2H{sub}6 on high-K gate oxide, ZrO{sub}2, has been investigated in the temperature range from 475°C to 550°C. The influence of surface reactions on growth characteristics such as the incubation of growth, roughness of the SiGe layer, and the interface reaction of the SiGe film with ZrO{sub}2 were studied using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). From our analysis we conclude that ZrO{sub}2 reacts with Si and forms zirconium silicide in the temperature range between 500°C and 550°C. The surface roughness of amorphous SiGe layers increase from 0.5nm to 1.5nm by increasing Ge content from 0.1 to 0.3. A further increase of surface roughness is observed from less than mm to 5nm as SiGe layer transitions from an amorphous to a poly crystalline layer.
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