Short Wavelength a-Si:H Photodetector for Bio-molecular Fragment Sizing

Abstract

A gel electrophoresis technology based on absorption of ultraviolet radiation for fragment sizing of bio-molecular segments such as protein and nucleic acid is introduced for the first time. The new technology has the potential to improve conventional gel electrophoresis method by lowering the cost and increasing the throughpxcvfut. A cost effective, high sensitivity, short wavelength selective detector is an essential component to enable the proposed technology. In this thesis, hydrogenated amorphous silicon (a-Si:H) metal semiconductor metal(MSM) are investigated as the short wavelength detector of choice. The operation of planar MSM photoconductor-based photo detectors with very thin a-Si:H film thickness and aluminium electrodes is investigated. Experimental results of photocurrent measurements as well as responsivity and quantum efficiency are presented. The MSM photodetectors presented are fully compatible with state-of-the-art staggered gate thin film transistor (TFT) fabrication processes to enable large area pixel arrays for bio-molecular imaging.