COLOR DETECTION USING AMORPHOUS-SEMICONDUCTOR THIN-FILM ALLOYS

The optical and opto-electronic properties of amorphous silicon-based semiconductor alloy films have been used to construct colour-sensing d evices in combination with conventional silicon photodetectors. it is shown that these films can be used either in a passively or an activel y filtering mode, with the first mode allowing for spectrally dispersi ve colour sensing and the second for the sensing of small relative cha nges with sub-nanometre resolution. The fabrication and properties of such sensors are described and potential applications with regard to t he measurement of non-optical quantities are pointed out.