Calibration of a 2 dimensional hydrogenated amorphous silicon thin film position sensitive detector (2D a-Si:H TFPSD)

Abstract

It is well known that for a 2 dimensional hydrogenated amorphous silicon thin film position sensitive detector (a-Si:H TFPSD), the calculated coordinates of the position, from the currents measured on the PSD, do not represent the real spot position. The errors result from the generally used position-current expression, and also from device fabrication defects such as the inhomogeneity of TCO thickness and the electrode contact resistance. The best way to correct the errors is to calibrate the device. In this paper, we present a calibration method developed earlier for a smart pressure sensor to calibrate a 2D tetralateral a-Si:H TFPSD. The calibration algorithm is presented. Experimental results are shown and the calibration error is discussed.