A sub-micron-thick InGaAs broadband (400-1700 nm) photodetectors with a high external quantum efficiency (>70%).

A sub-micron-thick InGaAs photodetectors (PDs) with a broad spectrum coverage (400-1700 nm) and high external quantum efficiency (EQE) (>70%) were successfully demonstrated through guided-mode resonance structure and surface layer thinning process. It showed the outstanding EQE of 83.8%, and 65.5% at 1000 nm, 1550 nm for 500-nm-thick InGaAs absorption layer, respectively. Compared to previous results, thickness reduction by 6.8 times and comparable QE were simultaneously achieved.