Infrared detector cell - pref. based on cadmium mercury telluride or lead tin telluride semiconductors with getter layers

摘要

The surface (al) of the semiconductor (a), and/or the metal contacts (b) covering surface (al) are at least partly covered with a getter layer (c). Layer (c) is pref. a silicon oxide, a silicon nitride, polycrystalline Si, or a mixt. of these substances, and layer (c) pref. includes getter doping elements from gps. III or V of the periodice system, esp. P, As or B. Layer (c) pref. covers the side of semiconductor (a) opposite the light entry window, or both side and in the window, where layer (c) has an appropriate refractive index. Layer (c) is pref. formed in an evacuated plasma reactor fed with a mixt. of SiH4, N2, residual O2, and a gas contg. the dopant, layer (c) being formed at 20-300 degrees C. A passivating layer (d) of ZnS may be used on the cell. Used esp. for photoconductors with no barrier layer junciton; or photodiodes with a barrier layer. The semiconductors (a) must be driven at very low temp. (77 degrees K.), and the invention provides a getter layer (c) increasing the sensitivity and working life of the cell.