Bias sensitive a-Si(C): H multispectral detectors

New types of a-Si(C):H thin-film multispectral detectors were designed and successfully fabricated. It was found that the controlling of drift length in the active regions provides a simple and useful criterion for the design, by the aid of which novel multispectral detectors with ni´pi´δ(n)in or pini´δ(p)ip structure were developed. The device with a ni´pi´(δn)in structure show´s spectral response peaks located at 450, 550, and 600 nm under bias voltages of 4.5, -1.5, and -7.0 V, respectively. This response is very similar to that of the human eye. In the corresponding pi´ni´δ(p)ip structure the maximum response can be shifted to 510 nm at a bias of -6.0 V, 560 nm at 1.0 V, and 610 nm at 5.5 V. Moreover, the prototypes exhibit excellent linearity within an illumination range from 10¹¹ to 10¹⁵ photons cm^-2 s^-1 and a high dynamic range of more than 56 dB under illumination of 1000 Ix