Dilute nitride resonant cavity enhanced photodetector with internal gain for the λ ～ 1.3 μm optical communications window

摘要

We report on a novel dilute nitride-based resonant cavity enhanced photodetector (RCEPD) operating at 1.286 μm. The RCEPD was fabricated using 21 pairs top and 24 pairs bottom GaAs/AlGaAs distributed Bragg reflectors for mirrors and 7nm thick nine GaAs/Ga_(0.65)In_(0.35)N_(0.02)As_(0.98) quantum wells as the absorption region. For a 15 μm diameter window, the photocurrent at 1.286 μm is 27 μA and 42 μA, at V = 0 and -1V, respectively, whereas the dark current is as low as 1.7 nA at -1 V. At the operating wavelength, an excellent wavelength selectivity with a full width at half maximum (FWHM) of 5 nm, and a high quantum efficiency of 43% are demonstrated. The device exhibits significant internal gain at very small reverse bias voltages of V ≥ -2 V with an overall quantum efficiency of 67%. These are the best ever recorded values for a dilute nitride RCEPD.