Role of a-Si in enhancing the current gain of Si-based MSM photodetector using conventional method

Role of a-Si in enhancing the current gain of Si-based MSM photodetector using conventional method is reported.the effect of a thin un-hydrogenated amorphous silicon layer (a-Si) on the performance of Si-based MSM photodetector (MSM-PD) was studied. Thermal evaporation technique was used to deposit the aSi layer on crystalline silicon substrate. a-Si layer was shown to decrease dark current of Si-based MSM-PD up to five orders of magnitude. a-Si layer was used as barrier enhancement layer in one MSM structure and capping layer in another structure. At applied bias of 5V, the latter structure exhibits lower dark current leading to photocurrent-to-dark current ratio of ~ 800 (white light 15W).