Charge collection mechanisms in a sub-micron grated MSM photodector: field analysis

Abstract

Enhanced charge collection mechanisms due to sub-micron wall-like silicon structures on the active surface of a metal-semiconductor-metal (MSM) photodetector were studied through the analysis of transmitted electromagnetic energy with and without the structural changes. Analysis shows that rearranging the walls to a square lattice (cubic or rectangular shaped structures) could improve the charge collection efficiency further. Further studies were done to show that there exists a certain critical percentage of the area covered by the gratings over the detector after which the charge collection efficiency starts to decrease.