表面悬挂键导致硅纳米线掺杂失效机理的第一性原理研究  

Investigation of the doping failure induced by DB in the SiNWs using first principles method

作　　者：梁培[1] 刘阳[1] 王乐[1,2] 吴珂[1,2] 董前民[1] 李晓艳[1] 

机构地区：[1]中国计量学院光学与电子科技学院,杭州310018 [2]浙江大学信息学部,杭州310018

出　　处：《物理学报》2012年第15期142-146,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61006051;61177050);浙江省自然科学基金(批准号:Y407370;Y6100244;Z1110222)资助的课题~~

摘　　要：利用第一性原理方法,本文计算了B/N单掺杂SiNWs,以及含有表面悬挂键的B/N单掺杂硅纳米线的总能和电子结构,计算结果表明,悬挂键的出现会导致单原子掺杂失效.能带结构分析表明,B/N掺杂的H钝化的SiNWs表现出正常的p/n特性,而表面悬挂键(dangling binding,DB)的存在会导致P型(B原子)或者n型(N原子)掺杂失效;其失效的原因主要是因为表面悬挂键所引入的缺陷能级俘获了n型杂质(p型杂质)所带来的电子(空穴);利用小分子(SO_2)吸附饱和悬挂键可以起到激活杂质的作用,进而实现Si纳米线的有效掺杂.First-principles calculations are employed to investigate total energies and electronic structures of the B/N doped silicon nanowires,the B/N doped silicon nanowires with and without dangling bond（DB）.And the calculation indicates that the DB would lead to the doping failure.Band-structure calculations indicate that B/N doped silicon nanowires without dangling bond show regular p/n type of the charge carrier,while the dangling bond would cause signal atom doping failure,which is not due to the transfer of electrons, but results from the capturing of the electron（hole） by the defect energy level induced by the surface dangling bond.Moreover, the small molecule adsorption can reactivate impurities doping p/n characteristics.The reactivation mechanism is not the transfer of the electrons,thus it can hold the doping characteristics.

关 键 词：掺杂失效 第一性原理 硅纳米线 悬挂键 

分 类 号：TB383.1[一般工业技术—材料科学与工程]