外延阻挡杂质带探测器的抗反射

Antireflection coating for epitaxial blocked impurity band detector

传统外延阻挡杂质带探测器由于其材料物性和特殊的结构设计存在很强的反射,这些能量损失非常不利于器件的探测性能。报道了一种类光栅双层超构表面微结构阵列,并将此人工微结构引入到外延阻挡杂质带红外探测器以抑制对入射光的反射。实验结果显示,具有超构表面微结构阵列的器件在波长30μm处反射率低于3%,在25.3∼32.2μm波段范围内反射率低于20%。同时,该超表面减反微结构对入射光的偏振还具有很强的选择性,符合第四代焦平面发展需求。

When an infrared wave is incident on the traditional epitaxial blocked impurity band detector,part of wave energy would be reflected by the device due to its special structural design and the properties of the constituent materials. The energy loss is obviously detrimental to the performance of the device. Here,a kind of bilayer metasurfacebased microstructure array is introduced into the epitaxial blocked impurity band infrared detector for suppression of reflection. Experimental results show that the reflectance of the proposed metasurface-based device is lower than 20% in the wavelength range of 25. 3~32. 2 μm,particularly,which is even less than 3% at the wavelength of 30 μm. Meanwhile,the proposed metasurface antireflection coating also has strong polarization selectivity for incident wave,which meets the requirement for the fourth-generation focal plane arrays development.