摘要
采用半经验紧束缚近似方法对生长在ＧａＳｂｘＰ１－ｘ（００１）衬底上ＧａＰ的电子能带结构进行计算。ＧａＰ为间接能隙型的半导体，计算表明，当衬底中Ｓｂ组分ｘ≥０．５７时，应变的ＧａＰ薄层由间接能隙变成直接能隙的半导体。因应变，ＧａＰ原来简并的最低Ｘ点导带能级及价带顶（Γ点）能级发生分裂。随着Ｘ增大，分裂值变大。文中最后计算了价带能级到导带底跃迁的振子强度，对发光效率作了讨论。
T he energy band structures of a thin strained GaP layer Oil GaSh.P1-x (001) substrate are calculated by the semi-empirical tight-binding method in the paper. The calculated results show that the thin strained GaP layer can change its feature from an indirect gap into direct gap if the composition x is larger than 0. 57. Due to deformation, the degeneration of the lowest conduction band at X point and the top of valence band(at P point)is destroyed. The splitting values increase with the composition x. Finally, oscillator strength between the valence band and the bottom of conduction band is calculated. The light emission efficiency is also discussed.
出处
《固体电子学研究与进展》
CAS
CSCD
北大核心
1996年第4期325-330,共6页
Research & Progress of SSE
关键词
紧束缚近似
直接能隙
能带结构
半导体
Semi-empirical Tight-binding Method Direct Gap Band Structures
