摘 要近年来，半导体在不同条件下费米能级的确定，以及深能级缺陷对发光效率的影响等，都受到了研究人员的广泛关注。本文中所使用的方法是以密度泛函理论为基础的第一性原理方法，采用 Materials Studio 8.0 中的 CASTEP 模块建立不同电荷的氧空位和氧间隙位的 β-Ga2O3，对于不同的结构进行优化，在优化的基础上我们计算了每个结构的生成焓及形成能，并找到生成焓最低的结构，分析这些结构的晶格常数、体系总能量的变化趋势，以及形成能随费米能级的变化。得出了 三 种 氧 空 位 对 应 的 缺 陷 能 级 到 价 带 顶 之 间 的 距 离 分 别 为 VO(I) =3.31eV、VO(II)=2.70eV 和 VO(III)=3，57eV。以上距离均比 1 大，这种情况说明了VO 均为深施主。并由实验得出 β-Ga2O3 一号氧空位是深能级缺陷。上述分析对于本实验中对影响半导体发光效率的因素进行研究探讨具有指导意义。关键词：β-Ga2O3；第一性原理；形成能AbstractIn recent years, the determination of Fermi energy levels in semiconductors under different conditions and the effect of defects in deep energy levels on luminous efficiency have attracted extensive attention from researchers.Used in this article the method is based on density functional theory of the primary principle of method, using Materials Studio CASTEP module in the 8.0 to build different charge oxygen vacancy and interstitial oxygen beta Ga2O3, for different structure optimization, on the basis of optimized we calculated the formation enthalpy of each structure and formation energy, and find the lowest formation enthalpy structure, analyzing the structure of the lattice constant and the change trend of total energy system, and can form along with the change of Fermi level.The distances between the defect energy level corresponding to the three oxygen vacancies and the valence band top are VO(I) =3.31eV, VO(II)=2.70eV and VO(III)= 3,57 eV, respectively.The above distances are all larger than 1, which indicates that ...
