Voltage controlled colour separation in two-terminal a-Si:H based sensor structures

Abstract

Various arrangements of stacked thin film photodiodes are capable of generating colour signals from two-terminal devices in a sequential manner with a properly cycled sequence of read-out voltages. We report on the performance and internal limitations of different amorphous silicon based n-i-p-i-n or p-i-i-n sensor structures. For the latter, the band gap varies during the course of deposition of the intrinsic layers. The full benefit of this type of sensors unfolds in conjunction with the advantage of the speed, flexibility, maturity, and cost-effectiveness of modern application-specific integrated circuits in Thin-Film on ASIC systems.