Optical Probing Position Sensitivity Characteristics of a Photodetecting Element Based on High-Resistivity CdSe Layers

Abstract

The output voltage, position sensitivity, and spectral sensitivity of a photodetecting element based on high-resistivity photosensitive CdSe layers have been shown for the first time to decrease hyperbolically with increasing layer thickness (in the range 6–60 μm) and increase linearly with increasing input electric current. The high position and spectral sensitivity found in this study (70.8 mV/(mm μA mW) and 375 mV/(μA mW), respectively), which considerably exceeds that of cadmium telluride layers, demonstrate that high-resistivity CdSe layers have considerable potential as a material of position-sensitive photodetectors.