A method for designing electromagnetic resonance enhanced silicon-on-insulator metal-semiconductor-metal photodetectors

Methods of using a combination of electromagnetic resonance modes including surface plasmons and Fabry-Perot cavity resonances and other optical modes including Wood-Rayleigh anomalies and diffraction to enhance the performance of metal-semiconductor-metal photodetectors (MSM-PDs) fabricated on silicon-on-insulator (SOI) substrates are described. The characteristics of these optical modes are briefly described and their proper use in SOI MSM-PDs is described ill detail. Three algorithms that model the electromagnetic field produced by the incident beam, the quasi-static electric field produced by the applied bias, and the charge carrier motion, recombination and induced photocurrent are integrated together in a time-dependent way to accurately calculate the bandwidth and responsivity for a series of optical pulses. By using, a combination of optical modes, a structure with theoretical values of 50 GHz bandwidth and 0.17 A W-1 responsivity is designed. Other structures using different combinations of optical modes are described.