ZnTe—ZnS应变超晶格的光学性质

OPTICAL PROPERTIES OF ZnTe-ZnS STRAINED LAYER SUPERLATTICES

研究了常压MOCVD方法生长在GaAs(100)衬底上的ZnTe-ZnS应变超晶格光学性质。在77K温度下观测到了与载流子有关的带间跃迁复合。随着激发密度增加,高能子能带上的载流子参与发光过程增强。通过Kroing-Penney模型计算了ZnTe-ZnS应变超晶格的能带结构,并拟合实验结果解释了发光的起因。

Photoluminescence properties of ZnTe-ZnS strained layer superlattices (SLS) grown on GaAs (100) substrates by metal-organic chemical vapor deposition (MOCVD) at atmospheric pressure (AP) were studied. The interband transitions of the superlattices due to free electron-hole recombination were observed at 77K. At higher excess carrier densities, the recombination of subbands lying higher in energy becomes increasingly important. Energy band structures of the ZnTe-ZnS SLSs were calculated by using the Kronig-Penney model and taking into account the strain effects due to the lattice mismatches between the materials. The structure dependence of the PL is explained by the theoretical calculation fitted to the experimental data.