电场对含空位缺陷硅结构影响的第一性原理研究  

First-principle study on effects of electric field on Si vacancy structures

作　　者：秦汉[1] 盛洁[1] 李雷[1] 朱灿焰[1] 毛凌锋[1] QIN Han;SHENG Jie;LI Lei;ZHU Canyan;MAO Lingfeng

机构地区：[1]苏州大学智能结构与系统研究所,江苏苏州215000

出　　处：《电子元件与材料》2018年第3期10-17,共8页Electronic Components And Materials

基　　金：国家自然科学基金项目(61076102;61272105);江苏省自然科学基金项目(BK2012614);江苏省高校自然科学研究面上项目(15KJB510027);江苏省自然科学青年基金项目(BK20170346)

摘　　要：用分子动力学模拟和第一性原理计算分析方法,研究电场对含空位缺陷硅结构的影响。分子动力学结果表明,硅(100)晶面处的空位数量,总体随着电场强度的增强而增加。当电场在8.90×10~6 V/cm和1.35×10~7 V/cm之间时,空位数达到最大饱和数值10,并保持稳定。第一性原理计算结果表明,能带结构中的缺陷能级等效于降低价带和导带之间的带隙值,导致空位结构中隧穿电流变大。此外,缺陷能级也会导致空位结构中的静态介电常数变大,从而引起电容-电压特性值变大。By using molecular dynamic simulation method and first principle calculations method,the influence of electric field on silicon with vacancies were investigated.The molecular dynamics results demonstrate that the vacancy quantity in Si(100)surface increases along with the increase of electric field in general.The vacancy quantity reaches and keeps a maximum saturation value of10,when the electric field is between8.90×106V/cm and1.35×107V/cm.The first principle calculations reveal that the tunneling current is enhanced in vacancy structure.It is owing to that the gap value between valence band and conduction band is reduced by the defect levels in band structure.Besides,the static dielectric constant in vacancy structure gets lager,resulting in higher capacitor-voltage value.

关 键 词：硅晶体 电场 空位缺陷 带隙 电容-电压特性 隧穿电流密度 

分 类 号：TN304[电子电信—物理电子学] TB303[一般工业技术—材料科学与工程]