Investigation of a-Si:H PII(I)N color detector operation

Using numerical simulator, the operational principle of two-terminal a-Si:H based three-color detectors with the multi-layer multi-bandgap PIIN or PIIIN structure is investigated. Two different approaches, which lead to bias-controlled three-color detection, are described and evaluated in terms of spectral response, rejection ratio, color suppression, illumination intensity and bias-light. For both PIIN and PIIIN structure, bias-light dependence and intensity dependence is investigated. Numerical simulation results showed strong negative correlation between color separation and bias-light sensitivity. The importance of the transparent conducting oxide for the three-color detection limits is demonstrated.