Resistance selection of blind sensitive element in PC PbS IRFPA detector fabrication

Resistance selection of blind element used in linear photoconductive (PC) PbS detector for counteracting background current was analyzed. It was found that the blind element resistance can be chosen to be same as, or to be a fixed ratio to that of relevant sensitive element. And the ratio should be equal with ratio of biases applied to blind element and relevant detector. Two linear PC 1 128 PbS infrared focal plane array (IRFPA) detectors, with sensitive element size of 100 m 100 m, and blind element size of 100 m 100 m and 200 m 50 m, were fabricated and their performance were tested by IRFPA test system. Results show that when the working condition satisfied average responsivity and average detectivety are same for using different blind elements. Results validate the feasibility that background output uniformity improvement of IRFPAs by tuning the resistance of blind element.