蓝宝石衬底上6H-SiC单晶薄膜的化学气相淀积生长  

Single-crystalline 6H-SiC heteroepitaxial growth by chemical vapor deposition on sapphire substrates at reduced temperatures

作　　者：孙澜[1] 陈平[1] 韩平[1] 郑有[1] 史君[1] 朱嘉[1] 朱顺明[1] 顾书林[1] 张荣[1] 

机构地区：[1]南京大学物理系,江苏南京210093

出　　处：《功能材料》2004年第2期192-194,共3页Journal of Functional Materials

基　　金：国家重点基础研究专项资助项目(G20000683);国家自然科学基金资助项目(60136020)

摘　　要：　采用低压化学气相淀积方法以相对较低的生长温度(900～1050℃)在蓝宝石(0001)衬底上外延生长了6H SiC单晶薄膜。其晶体质量和结构由X射线衍射谱和喇曼散射谱的测量结果得到确定。俄歇电子能谱和X射线光电子能谱的观察表明所制备的6H SiC薄膜中的Si—C键的结合能为181.4eV,Si与C的原子比符合SiC的化学配比。扫描电子显微镜的分析显示6H SiC外延层和蓝宝石衬底间的界面相当平整。由紫外及可见光波段吸收谱的结果得到所生长的6H SiC的禁带宽度为2.83eV、折射系数在2.5～2.7之间,均与6H SiC体材料的相应数据一致。Single crystalline 6H-SiC films were heteroepitaxially grown directly on sapphire (0001) substrates at relatively low deposition temperatures of 900～1050℃ by a hot-wall low-pressure chemical vapor deposition system. The crystal quality and polytype of SiC epilayers are measured by the X-ray diffraction spectrum and the Raman scattering spectrum. The Auger electron spectrum and the X-ray photoelectron spectroscopy indicate that 6H-SiC films were stoichiometric and the bonding energy of the Si—C bond was 181.4eV. From the graph of the cross-sectional scanning electron microscopy, we can also find the interface between the 6H-SiC film and the sapphire substrate was rather flat. By the UV-vis optical-absorption spectrum the lowest indirect gap of the 6H-SiC epilayer was determined to be about 2.83eV. The 6H-SiC films have refractive indexes of 2.5～2.7 between 2.1eV and 3.1eV of the photon energy, identical to the value of the bulk 6H-SiC.

关 键 词：化学气相淀积 蓝宝石 6H-SIC 单晶薄膜 低温生长 碳化硅 

分 类 号：TN304.24[电子电信—物理电子学]