A novel sensor concept for detecting the fundamental components of the visible light has been developed. The multi-channel sensors based on three stacked amorphous thin film detectors are color moiré or color aliasing free due to their vertical integration. The four terminal devices enable the generation of three or six linearly independent spectral response curves at the same spatial position. The 3-channel sensor based on three stacked pin-diodes generates a red-green- blue signal with one shot, whereas the 6-channel sensor with three stacked pinip structures allows the detection of up to six linearly independent spectral response curves. The reproducibility of the complex layer sequences is enhanced by introducing a textured TCO-layer in the rear part of the device, which leads to a distinct scattering of the incoming light for longer wavelengths.
In order to gain information on how to improve the sensor performance, the sensors are characterized. The presented characterization model facilitates the quantification of color errors with regard to the human perception. Furthermore, the color errors of amorphous thin film sensors are compared with a commercial color CCD camera and a BiCMOS color-sensor.