J4 ›› 2012, Vol. 11 ›› Issue (4): 32-34.
从理论上计算生长在GaAs衬底上的InxGa1-xAs合金材料的带隙变化,分析应变对其能带结构的影响。结果表明,InxGa1-xAs所受应变与In组分近似为线性关系;在应变的影响下材料带隙变大,价带能级产生分裂。利用合金组分的变化与InGaAs带隙的变化关系,可实现对材料带隙的调节,对器件的研究设计提供参考。
The change of emerge-band gap of InxGa1-xAs ternary alloys grown on GaAs substrate was calculated theoretically. The band structure of epitaxial layer was affected by strain due to differences between the film and substrate lattice constants. Strains in the layer varied almost linearly with composition. It was indicated that the bandgap of strained InxGa1-xAs increased and valence band splitting occurred, compared to unstrained materials. This makes it possible to control the bandgap by altering the alloys composition and hence strain. It is useful to the devices design.