金属—半导体界面附近的空位电子态

THE ELECTRONICAL STATES OF THE VACANCY NEAR A METAL-SEMICONDUCTOR INTERFACE

本文用紧束缚模型发展了金属—半导体界面附近的空位理论。研究结果发现:空位对它附近区域的态密度有一定影响;空位的生成能随空位-界面间距的变化是一个振荡函数;空位趋向于朝界面处吸引。当系统中同时存在两个空位时,由于介质极化,空位之间要发生间接相互作用,其间接相互作用能随空位-空位间距的改变发生振荡。

This paper develops the theory of vacancies near a metal-semiconductor interface within a tight-binding model. It is shown that the local density of states is influenced only in the immediate vicinity of the vacancy,and that the vacancy-formation energy is an oscillatory function of the distance of the vacancy from the interface. For the specific interface considered the vacancies tend to be attracted towards the interface. When two vacancies are presented in the system,they interact,This is due to the polarization of the medium. This interaction is shown to have an oscillatory dependence on the interva-cancy separation.