Si中B-空位复合缺陷的电子结构

本文对Si中B-空位(BV)缺陷的电子结构,提出一个“五个空杂化轨道”的简化理论模型。用紧束缚的Koster-Slater格林函数方法,算得的空位最近邻原子的超精细相互作用常数,以及电子波函数在远离空位的几率分布都同电子-核子双共振实验结果相符合。理论确定的深能级位置同深能级瞬态谱的实验值相比拟。协调了现有BV°缺陷的实验资料,支持了B原子位于空位的次近邻,BV°缺陷处于B^-V⁺电荷态的结论。 关键词：

ELECTRONIC STRUCTURE OF BORON-VACANCY COMPLEX IN SILICON

A simplified "five vacant hybrid orbital" model is proposed for the boron-vacancy complex, and the defect wave function are calculated using an empirical tight binding Green function method under extended defect potential approximation. The calculated hyperfine interaction constants of the nearest neighbors of the vacancy and the probability distribution of defect wave function localized at atomic distants from the vacancy, are in good agreement with the electron-nuclear double-resonance experiment. The deep energy obtained is comparable with the value measured by deep-level transient-spectroscopy. The theoretical results provide a strong support to the conclusion that boron atom is located at the lattice position next to the vacancy and the defect is a B^-V⁺ charge state.