SELECTIVE OPTICAL SENSORS FROM 0.25 TO 1.1-MU-M BASED ON METAL-OXIDE-SEMICONDUCTOR HETEROJUNCTIONS

We present a set of high-efficiency optical sensors for I.he spectral range from 0.25 to 1.1 mu m based on metal oxide-semiconductor heteros tructures using different substrates: GaP, GaSe, AlxGa1-xAs, GaAs and Si. A set of several transparent conductive metal oxide films such as indium, tin and zinc oxides fabricated by the spray pyrolysis method a nd its doping procedure has been investigated. The results show that h eavily doped indium and tin oxide films are preferable as the active t ransparent conductive electrode in heterojunction surface-barrier stru ctures. The fabricated sensors exhibit several features such as proces s simplicity, high quantum efficiency, uniformity of sensitivity over the active area and a high response speed. Such sensors can be used fo r precision measurements in different scientific and technical applica tions. (C) 1998 Elsevier Science S.A. All rights reserved.