中文摘要：

分别在未沉积Ge和不同衬底温度（300、500、700℃）沉积Ge条件下，利用固源分子束外延（SSMBE）技术在Si衬底上外延SiC薄膜。通过反射式高能电子衍射（RHEED）、X射线衍射（XRD）、原子力显微镜（AFM）和傅里叶变换红外光谱（FFIR）等仪器对样品进行测试。测试结果表明，预沉积Ge的样品质量明显好于未沉积Ge的样品，而且随着预沉积温度的升高，薄膜的质量在逐渐地变好。

英文摘要：

The SiC films were grown by solid source molecular beam expitaxy （SSMBE）on substrates of Si and Si with a Ge layer,pre-deposited at different temperatures（300,500 and 700℃ ）. The microstructures and properties of the SiC films were characterized with reflection high energy electron diffraction（RHEED）,X-ray diffraction （XRD）, atomic force microscopy（AFM）, and Fourier transform infrared spectroscopy （FTIR）. The impact of Ge layer on SiC properties was studied. The results show that the Ge layer and its growth temperature strongly improve the properties of SiC films. In- teresting finding is that a higher Ge growth temperature results in a better crystal structure. Possible mechanisms were also tentatively discussed.