Hybrid InSb focal plane array fabrication

Abstract

Large two-dimensional photovoltaic infrared detector arrays have been produced using the hybrid combination of InSb coupled to a silicon CCD. The hybridization process uses indium interconnect pads, which electrically couple each InSb photodiode to a CCD input structure. The entire InSb array is optically thin to allow the backside illumination of the InSb for high packing density. This process is also applicable to other intrinsic detector materials, such as InGaSb and HgCdTe. Production of 32 × 32 mosaic arrays with elements on 4-mil centers has demonstrated high interconnect yield and reliability. Fabrication of larger 58 × 62 arrays of similar design is progressing.