High rate deposition of a-Si:H films for optoelectronic detectors by VHF-GD

Abstract Optoelectronic properties of a-Si:H Shottky barrier photodetectors grown by the VHF-GD process (Very High Frequency Glow Discharge) at a rate of 20 A/s are presented. The high deposition rate permits the fabrication of thick low cost a-Si:H layers. The thickness of the intrinsic a-Si:H layer was varied from 0.4 μm to 9 μm for light detection between 400 nm and 700 nm. The authors show that the devices have comparable properties to conventional GD-thin-film detectors even if deposited at high rates. Typically, a photovoltaic gain of 10 6 at 650 nm (1 mW/cm 2 ) and a rise-time of 1 μs were measured for a 5 μm thick detector.