Strong Responsivity Enhancement of Quantum Dot-in-a-Well Infrared Photodetectors Using Plasmonic Structures

Detector responsivity enhancement from integrating optimized plasmonic structure layers into quantum dot-in-a-well photodetectors is investigated by a finite integration technique-based simulation. It is found that by including a 0.1 mu m thick gold hole-array layer onto a backside illuminated photodetector, the peak detector responsivity is enhanced by nearly a factor of 8. A 0.2 mu m thick gold disk-array layer improves the peak responsivity by around 15 instead. The calculated enhancement factors show a good agreement with experimental data by Gu etal.([1]) and Lee etal.([2]) Simulation method and analytical analysis accomplished in this paper provide a generalized approach to design optimal plasmonic structures integrated to various infrared detecting device configurations.