Thin film detector for color recognition: an experimental and numerical study

We investigated the performance of color sensitive pi-i-i-n diodes based on amorphous silicon. The detectors are developed with respect to the mu r (c arrier mobility x lifetime) product and the band gap of the individual i-la yers resulting in a voltage controlled spectral sensitivity. Since the line ar independence of the spectral response and a linear response of the photo current on the incident light intensity is a prerequisite for the generatio n of a red-green-blue (RGB) signal, the effect of additional bias illuminat ion on the spectral sensitivity is measured. To gain insight into the optoe lectronic properties of these devices we carried out numerical simulations and compared them with experimentally determined spectral sensitivities. (C ) 2000 Elsevier Science B.V. All rights reserved.