Kinetics of the high-temperature thermal decomposition of silanes and alkylsilanes

Kinetics of dichlorosilylene trapping by methane and mechanism and kinetics of the methyldichlorosilane decomposition

“…Thus H 2 (not HCl) elimination is the main primary dissociation channel of dichlorosilane [1], and methane elimination is only slightly slower (a factor of six) than H 2 elimination in the shock initiated decomposition of methylsilane [11]. As for Si 9 C bond fission, both methane elimination and bond fission are competing reactions in the shock initiated decompositions of dimethylsilane [12] and trimethylsilane [13], in spite of the 25 to 30 kcal/mol higher activation energy for bond fission. Therefore, some bond fission initiation in the MeSiHCl 2 decomposition is possible.…”

Secondary dissociation pathways of ethylsilylene radical on ground and excited state potential energy surfaces

“…This suggests that another channel may be responsible for CH3CH=SiH2 production, viz., reaction (5). The net energy of activation for the formation of CH3CH=SiH2 is 342-6 kJ mol ~ via CH3CH2SiH 3 --~ CH3CH2SiH + H 2 "-* CH3CH=SiH 2 + H 2 (8) as compared to 107.9 kJ mol -~ required by the primary pathway,…”

“…The activation energy for the process is 201.6 kJ mol-t at the MP4/6-3 IG* level. This compares favourably with the experimental estimate of 211.7 kJ mol -t for the activation energy for the formation of silicon atoms from vinylsilylene, viz., CH2=CHSiH --, QH4 + Si( L D) [5].…”

“…The key intermediate implicated in the formation of amorphous silicon thin films is the silylene (Sill2) radical [1][2][3][4][5][6]. Consequently, improving deposition rates of organosilanes entails identifying chemical sources of Sill2 from the decomposition process, so yields of the intermediate can be enhanced.…”

“…One of the simplest alkysilanes is ethylsilane. Silylene has been suggested to result from primary dissociation pathways of ethylsilane through a 1,2-SiH2 elimination process [5,6,12], viz., CH3CHESiH 3 --~ CEH 6 + Sill 2.…”