Large area and high sensitivity a-Si:H/a-SiC:H based detectors for visible and ultraviolet light

In this article we discuss the fabrication and performance of a-Si:H/a-SiC:H based ultraviolet sensitive devices. They were deposited over a large area (10 cm310 cm) in p-i-n configuration using a new, multichamber, ultrahigh vacuum plasma enhanced chemical vapor deposition facility. The intrinsic layer thickness was 10–100 nm. The devices were characterized in the spectral range 365–660 nm and showed good sensitivity in the UV ~365 nm!. A good rejection of visible light was also measured. Responsivity as high as 0.30 A/W was measured at 365 nm for samples where the p layer and i layer were 5 and 10 nm thick, respectively. The linearity of the photogenerated current as a function of photon flux was measured. It was found that over an area of 25 cm 2 the uniformity was within 15%. Using a laser ~200 mW at 351 and 363 nm! the aging characteristics were measured and showed a 25% decrease in responsivity after the absorption of 105 J cm22 under operating conditions.