MICRODOPED AND MICROCOMPENSATED AMORPHOUS-SILICON FILMS FOR INFRARED DETECTION

In this letter, we demonstrate detection at room temperature of near a nd medium infrared (IR) radiation by using microdoped and microcompens ated amorphous silicon as a separation layer in a p-n junction. The IR absorption in the 800-4600-nm wavelength range is due to the high den sity of trap states induced by the dopant impurities. In particular, w e argue that detection in the medium IR range involves localized state s near the valence band associated with boron doping. Detection of nea r-infrared (NIR) radiation can be related, instead, to localized state s near the conduction band caused by distortion of the amorphous netwo rk due to the very low concentration of phosphorous and boron.