First-principle calculation on the defect energy level of carbon vacancy in 4H-SiC
First-principle calculation on the defect energy level of carbon vacancy in 4H-SiC
复制标题
4H SiC中碳空位缺陷能级的第一性原理计算
DOI：
10.1088/1674-1056/19/10/107105
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发表时间：
2010-10-01
影响因子：
1.7
通讯作者：
Zhang Yi-Men
中科院分区：
文献类型：
--
作者：
Jia Ren-Xu;Zhang Yu-Ming;Zhang Yi-Men
首先，采用基于密度泛函理论的平面波第一性原理超软赝势方法计算了纤锌矿4 H-SiC的电子结构，研究了其结构变化、能带结构和态密度.然后用碳空位取代4 H-SiC中的碳，研究了带隙中碳空位的缺陷能级。计算结果表明，碳空位在4 H-SiC中产生了新的缺陷能级，并确定了其在带隙中的位置，具有深受主的特征。根据计算结果，对4 H-SiC的绿色发光给出了合理的解释，并与测量结果进行了比较。
First, electronic structures of perfect wurtzite 4H-SiC were calculated by using first-principle ultra-soft pseudo-potential approach of the plane wave based on the density functional theory; and the structure changes, band structures, and density of states were studied. Then the defect energy level of carbon vacancy in band gap was examined by substituting the carbon in 4H-SiC with carbon vacancy. The calculated results indicate the new defect energy level generated by the carbon vacancy, and its location in the band gap in 4H-SiC, which has the character of deep acceptor. A proper explanation for green luminescence in 4H-SiC is given according to the calculated results which are in good agreement with out measurement results.