在Si(111)上用有机溶胶凝胶甩膜热解法制备(0001)定向的6H-SiC薄膜

在Si(111)衬底上用聚苯乙烯溶胶凝胶甩膜并经950℃真空(10^-3Pa)热解处理法,制备出晶态SiC薄膜.用FTIR,XRD,TEM,RamanXPS等方法研究了SiC薄膜的晶体结构、微结构、组成以及各元素的化学态等性质.结果表明制得的是沿(0001)高度择优取向的晶态6H-SiC薄膜.膜中SiC晶粒沿c轴柱状生长,其最大尺寸约150nm,膜厚约为0.3μm,SiC中的Si/C比约为1.表层有少许污染C(CH和CO)和少量O(Si₂O₃,CO态氧和吸附氧).从对比实验可知,在热解时将甩膜的Si片与另一空白Si片面面相贴可明显增加SiC的生成量.关键词：碳化硅薄膜溶胶凝胶

EPITAXIAL GROWTH OF (0001)ORIENTED 6H-SiC FILMS ON Si(111) SUBSTRATE BY ORGANIC SOL-GEL FILM ANNEALING

SiC films were prepared on Si(111) substrates by annealing polystyrene gel films at temperature 950℃ in vacuum(10－3 Pa).Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD), Transmission electron microscopy(TEM).Raman scattering and X-ray photoelectron spectroscopy(XPS) were used to study the morphology of the surface, crystal structure. composition and chemical state of the element of the SiC films. It revealed that the films consisted of preferentially oriented crystalline 6H-SiC epilayer which grew along(0001) planes parallel to Si(111) planes. The ratio of Si to C was about 1 and there were some carbon and oxide contaminant species in the form of CH, CO and Si2O3 along with a small amount of adsorptive oxide at the surface of the films. The polycrystalline grains in the films grew cylindrically along c axis.Their maximum size was about 150nm. The film was smooth. dense and uniform with a thickness of about 0.3 μm. It was found that covering the polystyrene film with a Si plate could increase the quantity of SiC during anncaling.