Void-free β-SiC films were deposited on Si（001） substrates by laser chemical vapor deposition using hexamethyldisilane（HMDS） as the precursor. The effect of the time of introducing HMDS, i e, the substrate temper...Void-free β-SiC films were deposited on Si（001） substrates by laser chemical vapor deposition using hexamethyldisilane（HMDS） as the precursor. The effect of the time of introducing HMDS, i e, the substrate temperature when HMDS introduced（T_（in））, on the preferred orientation, surface microstructure and void was investigated. The orientation of the deposited SiC films changed from 〈001〉 to random to 〈111〉 with increasing T_（in）. The surface showed a layer-by-layer microstructure with voids above T_（in） ≥ 773 K, and then transformed into mosaic structure without voids at T_（in）= 298 K. The mechanism of the elimination of voids was discussed. At T_（in） =298 K, Si surface can be covered by an ultrathin SiC film, which inhibits the out-diffusion of Si atoms from substrate and prohibites the formation of the voids.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51372188 and 51521001)the 111 Project(B13035)+3 种基金the International Science&Technology Cooperation Program of China(2014DFA53090)the Natural Science Foundation of Hubei Province,China(2016CFA006)the National Key Research and Development Program of China(2017YFB0310400)the Fundamental Research Funds for the Central Universities(WUT:2017II43GX,2017III032)
文摘Void-free β-SiC films were deposited on Si（001） substrates by laser chemical vapor deposition using hexamethyldisilane（HMDS） as the precursor. The effect of the time of introducing HMDS, i e, the substrate temperature when HMDS introduced（T_（in））, on the preferred orientation, surface microstructure and void was investigated. The orientation of the deposited SiC films changed from 〈001〉 to random to 〈111〉 with increasing T_（in）. The surface showed a layer-by-layer microstructure with voids above T_（in） ≥ 773 K, and then transformed into mosaic structure without voids at T_（in）= 298 K. The mechanism of the elimination of voids was discussed. At T_（in） =298 K, Si surface can be covered by an ultrathin SiC film, which inhibits the out-diffusion of Si atoms from substrate and prohibites the formation of the voids.
