α-SiC“非汉字符号”表面结构的第一性原理计算  

First-principles study on α-SiC “非汉字符号” surface structure

作　　者：谢长坤[1,2] 徐彭寿[1,2] 徐法强[3] 潘海斌[3] 

机构地区：[1]中国科学技术大学结构分析开放实验室 [2]中国科学技术大学国家同步辐射实验室,合肥230029 [3]中国科学技术大学国家同步辐射实验室

出　　处：《物理学报》2002年第12期2804-2811,共8页Acta Physica Sinica

基　　金：国家自然科学基金 (批准号 :5 0 13 2 0 40 );中国科学技术大学"高水平大学建设"研究基地资助的课题~~

摘　　要：用全势缀加平面波方法 (FPLAPW)计算了α SiC及其非极性 (10 10 )表面的原子与电子结构 .计算出的α SiC晶体结构参量 :晶格常量和体积弹性模量与实验值符合得很好 .用平板超原胞模型来计算α SiC(10 10 )表面的原子与电子结构 ,结果表明表面顶层原子发生键长收缩并扭转的弛豫特性 ,表面阳离子Si,C向体内方向发生不同程度的位移 .表面重构的机理为Si,C原子由原来的sp3杂化方式退化为sp2 杂化 ,与其三配位异种原子近似以平面构型成键 .另外 。We present a theoretical calculation on the atomic and electronic structure of α SiC and its non polar (1010) surface using the full potential linear augmented plane wave (FPLAPW) approach. The calculated lattice constants and bulk modulus of α SiC crystal are in excellent agreement with experimental data. The atomic and electronic structure of α SiC (1010) surface have been calculated by employing slab and supercell models. It is found that the surface is characterized by a top layer bond length con tracting rotation relaxation in which both Si and C atoms have the tendency to move down toward the bulk to form planar configuration with their neighbours and Si moves further toward the bulk than C does. Furthermore, surface relaxation induces the transformation from semi metallic to semiconducting characterization.

关 键 词：表面结构 第一性原理计算 碳化硅 FPLAPW方法 电子结构 全势缀加平面波方法 半导体材料 

分 类 号：O472.1[理学—半导体物理]