Ultra Thin-Film MSM Photodetector with Low Parasitic Capacitance

Parasitic capacitance analysis of an ultra thin-film metal-semiconductor-metal (MSM) photodetector (PD) having the lowest capacitance per unit surface area is reported in this paper. Through cladding layers removing process using etching, 50-60 % decrease in the parasitic capacitance of the MSM photodetectors, compared to the conventional inverted thin-film MSM photodetectors, was obtained. The parasitic capacitance of the MSM photodetectors depending on etching time was optimized and analyzed using RF modeling techniques in this report.