单轴应力对量子阱红外探测器吸收波长的影响

Dependence of the Quantum Well Infrared Photodetector Absorption Wavelength on Uniaxial Stress

以单轴应力作用下超晶格量子阱应变能带理论为基础,采用电子反射与干涉方法,研究了单轴应力对超晶格能带的影响,推导了单轴应力与超晶格导带子能级的定量关系。以GaAs-AlGaAs-GaAs为例,具体计算了导带中子能级对应力的依赖关系,进而给出了单轴应力对n型AlGaAs-GaAs量子阱红外探测器(QWIP)吸收波长的影响。计算结果表明,随着单轴压应力的增大,量子阱红外探测器的吸收波长表现出较明显的变化。当单轴压力增大到1.3GPa,量子阱红外探测器的吸收峰值移动了将近1.1μm,并且基本与应力呈线性关系。量子阱红外探测器吸收波长连续可调范围5.57～4.46μm。

The dependence of the bandgaps of strained superlattice and quantum wells on uniaxial stress is studied, by using of the method of electron reflection and interference. The quantitative relation between the stress and the energy levels of GaAs-AIGaAs superlattice and quantum wells is obtained. Furthermore, the dependence of the energy levels in conduction band on uniaxial stress is calculated for GaAs-A1GaAs-GaAs. Then the dependence of absorption wavelength on the uniaxial stress is given in a quantum well infrared photodetector （QWIP）. The results show that the absorption peak moves nearly 1.1 ~m when the stress is increased to 1.3 GPa and the change with stress is basically linear. The peak of absorption wavelength can be tuned from 5.57 um to 4.46 um continuously in QWIP.