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

用改性等离子体电极研究了在硅表面大面积沉积3C-SiC薄膜。为了使等离子体变宽，将压力从原来的170 Torr降低到100 Torr，并对等离子体电极进行了改进。采用交流等离子体辅助CVD技术在60x40 mm^2 Si（100）晶圆上沉积了SiC薄膜。在900 ~ 1000℃的基片上形成的碳化层为除基片边缘外表面光滑平坦的单晶SiC薄膜。在950℃的衬底温度下，生长层得到了接近单晶的薄膜。随着SiH_4流动速率的增加，生长层中有包含多晶相和SiC球形颗粒的趋势。当SiH_4喷嘴与衬底的距离变宽时，生长层相对光滑平坦，没有SiC球形颗粒。然而，它们是多晶SiC薄膜。生长表面上过量的硅源使生长层形成多晶相。也就是说，在较低的衬底温度下，只要提供足够的SiH_4气体和直流偏压，就可以形成完美的单晶SiC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.