Some aspects of position‐sensitive photodetectors made of amorphous silicon

Abstract

AbstractPosition‐sensitive photodetectors detect an illuminated position without using image scanning. A large area detector of dual‐axis tetralateral PSD has been fabricated using amorphous silicon for low cost. The effective area of the device was 9.6 × 9.6 mm2, the detection deviation within 2 mm from the center was 0.3 mm and the pulse response time was around 1.5 ms. The resistive divider layer using Pd and Mo thin films provided good results. The position‐sensitive characteristics were simulated numerically by using Lucovsky's equation and the result was in good agreement with the experimental result. The analytical results lead us to the conclusion that in case of two‐dimensional dual‐axis tetralateral PSD, the nonlinearity in the position coordinate of the measured signal is caused by the introduction of both coordinate components for illuminated position (x0, y0) to each signal potential components at the x or y axis.