Vibrational study on the carbonization of Si surface

Abstract

The initial carbonization of Si (100) and (111) in the temperature range 600–1200°C, under atmospheric pressure, was investigated by probing changes of the surface Si–H vibrational modes using FTIR-ATR. When the samples were exposed to C 3H 8 with H 2 at 1000°C, without cooling down after in-situ etching, both Si–H vibrational modes associated with carbonization and Si–H vibrational modes indicating a H-terminated clean Si surface were observed simultaneously. This indicates that initial carbonization occurred as an island growth mode. When the samples were exposed to C 3H 8 with H 2 and heated up to the temperature range 600–1200°C, with a cooling down process after in-situ etching, Si–H vibrational modes associated with carbonization with broad spectral feature were obtained in the temperature range 1050–1200°C. This indicates that the carbonized surfaces were microscopically rough.