利用GaAs/AlGaAs量子阱结构, 研制了像元规模为640×512、中心响应波长在10.55 μm附近的红外焦平面阵列器件, 与50 K集成式制冷机耦合后, 测试了相关性能, 其等效噪声温差达到22.5 mK。焦平面组件通过了初步的开关机试验以及热真空试验后, 表现良好。考虑封装冷屏导致在面源黑体测试时产生的焦面照度不均匀问题进行了数值计算, 并分析了与近似解析计算的误差, 表明当F数变小时应当采用数值计算, 并认为探测器测试的非均匀性主要由照度不均匀贡献。针对10.55 μm量子阱探测器, 利用开源的MEEP FDTD软件, 进行了近场耦合的光场分布计算, 计算结果表明目前的结构参数在光衍射方面是比较接近优化的。

640×512 Quantum Well Infrared Photo-detector(QWIP) long wavelength infrared(LWIR) focal plane arrays(FPA) were made by using GaAs/AlGaAs quantum well structure. The response spectra were at 10.55 μm. Integrated with rotation sterling cooler which gave a temperature of 50 K, the FPA was measured to find the results that NETD was about 22.5 mK. The FPA assembly kept good performance after the switch-on-off cycling test and thermal vacuum test. The illumination non-uniformity of the focal plane with a cold shield was calculated with a numerical method. The results were compared with the approximate analytic method. It is shown that numerical method should be used for small F-numbers. Thus, the measured non-uniformity is believed to be dominated by the illumination non-uniformity. By using the MEEP FDTD software, calculation about the near-field photo-coupled electrical-field energy were designed and results show that current QWIP structure parameters are near optimized in term of optical diffraction.