Parameter Study of Resonator-Quantum Well Infrared Photodetectors

We recently proposed a resonator structure to increase the quantum efficiency (QE) of a quantum well infrared photodetector. In this paper, we performed a systematic study on its QE as a function of detector size and doping density. We found that the experimental result generally agrees with the prediction from electromagnetic modeling, and the resonant coupling scheme is effective with the pixel pitch as small as 6 μm. In addition, we modeled the potential detector performance at even smaller pixel pitches and found that the maximum QE occurs at 3-μm pixel pitch for 9-μm detection, where QE is predicted to be above 80%.