Chemical trends and s-p hybridization in the DX center in GaAs.
Chemical trends and s-p hybridization in the DX center in GaAs.
复制标题
GaAs DX 中心的化学趋势和 s-p 杂化。
DOI：
10.1103/physrevb.48.11804
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Oshiyama
中科院分区：
文献类型：
--
作者：
Saito;Oshiyama
基于局域密度近似下的超原胞模型，用第一性原理计算方法研究了GaAs中与Sn和S相关的DX中心。Sn相关的DX中心与断键配置的计算的发射势垒是由0.18 eV比在Si中低，与观察到的值（0.16 eV）从深能级瞬态光谱吻合得很好。这种相当低的发射势垒在锡相关的DX中心是由于弱的s-p杂化的Sn悬挂键在断键配置。在S的情况下，第一邻Ga畸变断键构型（Ga 1VGaSAs）-1比S畸变断键构型（S1 VAs）-1具有更低的能量，并且被证实在带负电荷的几何构型中具有最低的能量
The Sn- and S-related DX centers in GaAs are studied from first-principles calculations based on supercell models within the local-density approximation. The calculated emission barrier for the Sn-related DX center with the broken-bond configuration is lower by 0.18 eV than that in Si, in good agreement with the observed value (0.16 eV) from the deep-level transient spectroscopy. This considerably low emission barrier in the Sn-related DX center is attributed to weak s-p hybridization of the Sn dangling bond in the broken-bond configuration. In the case of S, the first-neighbor Ga distorted broken-bond configuration (Ga 1 V Ga S As ) -1 has lower energy than the S-distorted broken-bond configuration (S 1 V As ) -1 , and is confirmed to have the lowest energy among the negatively charged geometries