The chemisorption of H2C[Si(CH3)3]2 and Si6(CH3)12 on Si(100) surfaces
نویسندگان
چکیده
The chemisorption of bis~trimethylsilyl!methane ~BTM, CH2@Si~CH3!3#2! and dodecamethylcyclohexasilane ~DCS, Si6~CH3!12! on clean Si~100! surfaces has been studied by C 1s core-level and valence-band photoemission spectroscopy. Our model for the deposition of carbon by BTM involves decomposition into a –CH2Si~CH3!3 surface moiety for room-temperature adsorption, which further decomposes upon annealing to 550 °C to form a surface terminated primarily by CHx units. DCS deposits almost three times as much C on the surface as BTM. The data are consistent with DCS undergoing a ring opening and bonding to the surface as polydimethylsilane chains. Annealing both adsorbates to 950 °C causes a large decrease in the C 1s signal due to the fact that Si segregates to the surface at temperatures above 900 °C. The valence-band photoemission of Si~100! dosed with DCS at 950 °C is in good agreement with that of b-SiC, whereas the analogous BTM spectrum deviates significantly. @S0021-8979~97!02716-3#
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