Metal-Silicon Schottky Barrier Infrared Vidicon

A new type of infrared vidicon camera tube has been developed which overcomes many of the objections previously raised against this approach to infrared imaging. This new vidicon employs high beam velocity scanning of a matrix of metal-silicon Schottky barrier diodes. These diodes achieve mid-IR response as a result of internal photoemission over the metal-silicon barrier. Feasibility demonstration experiments have demonstrated good imagery, and have permitted the evaluation of certain key parameters such as the quantum efficiency coefficient C1 and resolution element size Ae. Using these parameters, it can be shown that a 5 micron tube using PtSip-type silicon diodes will be capable of 0.2 C Minimum Resolvable Temperature Difference at 500 TV lines resolution. For detection of high temperature 1000 K point sources, Noise Equivalent Power of 1.3 x 10 to the minus 11th power watts at Ae 0. 00008 sq cm is predicted. Considering the fact that infrared imagers employing these vidicons will be substantially less expensive 1 to 2 orders of magnitude than conventional imagers of comparable performance, these performance predictions appear quite attractive.