Surface reaction of CH SiH on Ge 100/ and Si 100/

Surface reaction of CH3SiH3on the Ge 100.and Si 100.surfaces was investigated in the low-temperature region of 400–5008C using ultraclean hot-wall low-pressure chemical vapor deposition CVD.systems, where CH3SiH3was supplied at a partial pressure of 18 Pa for 0–240 min. On Ge 100., the concentrations of Si and C deposited at 4008C and 4508C saturate to the value corresponding to the single atomic layer, but those at 5008C increase continuously with exposure time. Nevertheless, at all the temperatures studied, the concentration of deposited Si is nearly the same as that of deposited C. In the case of SiH4 exposure at 4508C at partial pressures of 6 and 60 Pa, it was found that the Ge atoms segregate on the top surface at the early stage of Si deposition. By comparing these results, it is considered that the adsorption of CH3SiH3 suppresses the Ge segregation. On Si 100., the C deposition by CH3SiH3has a similar tendency to that on Ge 100., but the initial deposition efficiency is lower than that on Ge 100.. Moreover, the FTIRrRAS Si-hydride peak shifts to the lower wave numbers after CH3SiH3exposure. These results suggest that CH3SiH3is adsorbed without breaking the Si`C bond on Ge 100.and Si 100.at 400–5008C. q2000 Elsevier Science B.V. All rights reserved