Low Temperature and Large-Area Deposition of 3C-SiC Films on Si by AC Plasma-Assisted CVD.

用改进的等离子体电极研究了在硅片上大面积沉积3C-SiC膜。采用交流等离子体辅助化学气相沉积技术在60×40 mm×2Si(100)衬底上沉积了碳化硅薄膜，将气压由原来的170Torr降至100Torr，并对等离子体电极进行了修饰。在900~1000ﾟC的衬底上形成的碳化层为单晶碳化硅薄膜，除衬底边缘外，其余表面光滑平整。当衬底温度为950ﾟC时，可以得到接近单晶层的薄膜。随着SiH_4流量的增加，生长层有由多晶相和碳化硅颗粒组成的趋势。当SiH_4喷嘴与衬底的距离变大时，生长层相对平坦，没有碳化硅球形颗粒。然而，它们是多晶碳化硅薄膜，硅源的过量供应使生长表面形成了多晶相。也就是说，在较低的衬底温度下，通过适当的SiH_4气体和直流偏压，可以形成完美的单晶碳化硅生长层。

Large area depositions of 3C-SiC films on Si have been investigated by modified plasma electrode. To make the plasma wider, the pressure was reduced from 170 Torr of the previous pressure to 100 Torr and plasma electrodes were modified.SiC thin films were deposited on 60x40 mm^2 Si (100) wafer by AC plasma-assisted CVD technique. Carbonization layrs formed at the substrate of 900-1000ﾟC were monocrystalline SiC films with smooth and flat surfaces except of substrate edges. Nearly monocrystalline films of grown layrs were obtained at the substrate temperature of 950ﾟC.The grown layr had a tendency to include a polycrystalline phase and SiC spherical particles with increasing the flow rate of SiH_4. When making a distance of the SiH_4 nozzle and the substrate wider, The grown layrs were relatively smooth and flat without SiC spherical particles. However they were polycrystalline SiC films.The excess supply of Si sources onto the growing surface make growth layr polycrystalline phase. In other words, it is suggested that perfect monocrystalline SiC growth layr can be formed at low substrate temperature by supplying the SiH_4 gas and DC bias adequately.