High efficiency, high speed GaAs thin film inversed MSM photodetectors

MSM photodetectors are attractive for integration with receiver circuits since they have lower capacitance p-i-n detectors with the same surface area. Low external quantum efficiency however, is a disadvantage of MSMs. Several research teams had investigated novel ways to enhance the quantum efficiency such as transparent indium tin oxide electrodes (ITO-MSM), and a Bragg mirror on the bottom to define a Fabry-Perot cavity. In this article, inverted MSMs (I-MSMs), with metallized fingers on the bottom of the MSMs, are reported at 950 nm in GaAs/AlGaAs, with record external quantum efficiency for normal incidence MSMs at this speed.

Duke Scholars

Author Nan Marie Jokerst Electrical and Computer Engineering