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美国陆军研究实验室以前已验证过一个大规格的1024×1024元的波纹量子阱红外光电探测器的焦平面列阵。该焦平面列阵的截止波长为8.6μm,并且用f/1.8的光具在76K温度处达到了背景限性能.像元的几何形状为短梯形,这种形状简化了处理技术,但却限制了量子效率。本文介绍使波纹量子阱红外光电探测器达到更高量子效率的两种方法。第一种方法是增加波纹的尺寸以获得更多的有效体积,并且采用一种近似三角形的像元形状以获得更大的反光面积。采取了这些改进措施之后,预计一对倾斜侧壁的量子效率约为35%,这已是以前所获值的两倍以上。第二种方法是利用波纹腔体内部的法布里-珀罗共振来增强垂直电场的强度.用这种方法可在某些谱区达到50%的高量子效率,而且既不必使用很厚的敏感层,也无须涂覆抗反射涂层.第一种方法已被用以生产一系列单色焦平面列阵,其实验结果将另文介绍.本文还描述一种电压可调探测器材料,用这种材料可使这些焦平面列阵获得多色探测的能力.
The US Army Research Laboratory has previously verified a large-format 1024 × 1024-element corrugated quantum well infrared photodetector focal plane array. The focal plane array has a cut-off wavelength of 8.6 μm and achieves a background limiting capability with f / 1.8 at 76 K. The geometry of the cell is short trapezoidal, which simplifies the processing technique but limits Quantum efficiency This article describes two ways to achieve a higher quantum efficiency of a ripple QWR photodetector. The first method is to increase the size of the corrugation to obtain more effective volume, and adopt an approximate triangular pixel shape to obtain a larger reflective area. With these improvements, it is expected that the quantum efficiency of a pair of sloping sidewalls will be about 35%, which is more than twice the value previously obtained. The second method is to use the Fabry-Perot resonances inside the corrugated cavity to enhance the vertical electric field intensity, which achieves a high quantum efficiency of 50% in certain spectral regions without the need for thick Sensitive layer, there is no need to apply anti-reflective coating.The first method has been used to produce a series of monochromatic focal plane arrays, the experimental results will be introduced separately.This paper also describes a voltage-adjustable detector material, With this material, these focal plane arrays are capable of multi-color detection.