Si(111)衬底上3C-SiC的固源MBE异质外延生长

Heteroepitaxial Growth of 3C-SiC on Si(111) by Solid Source Molecular Beam Epitaxy

国内首次利用固源分子束外延(MBE)技术,在衬底温度为1100℃时,以Si(111)为衬底成功地外延生长出了3C-SiC单晶薄膜。通过X射线衍射(XRD)、拉曼光谱(Raman)以及原位反射高能电子衍射(RHEED)等手段研究了外延薄膜的晶型、结晶质量、外延膜与衬底的外延取向关系,并考察了薄膜制备过程中衬底的碳化对薄膜质量的影响。结果表明,外延膜与衬底晶格取向完全一致;碳化可以减小SiC和衬底Si之间的晶格失配、释放应力、引入成核中心,有利于薄膜单晶质量的提高;碳化温度存在最佳值,这一现象与成核过程有关。

Monocrystalline 3C,-SiC films were successfully grown on Si（ 111 ） substrates at an optimized subbstrate temperature of 1100℃ by molecular beam epitaxy（MBE） using solid-sources of C and Si for the first time in China.The fdms, the epitaxial orientation,and the rehfions between the fdms and sustrates were characterized by in-situ reflection high energy electron diffraction （RHEED）, X-my diffraction （XRD） and Raman spectra. The effect of substrate carbonization on growth of SiC was studied. The results show that the films are 3C- SiC with all cubic axes parallel to the substrates＇. The carbonization benefits the quality of films because it can compensate the large lattice-mismatch and introduce more nucleation centers of SiC microcrystal.