In_0.52Al_0.48 As Based Single Photon Avalanche Diodes with Stepped E-Field in Multiplication Layers and High Efficiency beyond 60%

We carry out an In0.53Ga0.47As/In0.52Al0.48As single photon avalanche diode which exhibits a single photon detection efficiency exceeding 60% at 1310 nm and neat temporal characteristic of 65 ps. A novel concept of dual multiplication layer is incorporated to avoid the tradeoff between dark count rate, afterpulsing and timing jitter, paving the possibility to improve the overall performance of a single photon detector. Based on this elevated device structure, we further optimize the detection efficiency and timing jitter by employing a delicate mesa structure to better confine the electric field distribution within the central multiplication region. For our detector operated under gated mode, a shorten gate width together with an increase of excess bias percentage leads to a significant improvement in the detection performance. We eventually achieve a single photon detection efficiency of 61.4% without the involvement of afterpulsing at the gating frequency of 10 kHz for 200 K.