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InGaAs/InP Negative Feedback Avalanche Diode (NFAD), with a quenching negative feedback resistor integrated, is a new type of high-sensitivity and all-solid-state semiconductor device based on Single Photon Avalanche Diode (SPAD) structure. This paper proposes a near-infrared free-running single photon counting integrated module based on InGaAs/InP NFAD. It contains an active quench and extraction circuit, sampling and processing circuit, upper computer software design and TEC etc., and is designed to serve a NFAD adopting absorption-attenuation-charge-multiplication (SAGCM) structure with InGaAs/InP materials and operating in Geiger mode. In this module, we specifically design a full differential amplifier and comparator to exploit the performance of NFAD by detecting and extracting the weak avalanche signal and converting it into TTL pulse. The avalanche detection discrimination threshold voltage is adjustable by external high-precision DAC, and a programmable dead time could be set by Field Programmable Gate Array (FPGA). The module system provides timing logic in order to avoid false counting caused by the coupling noise of the differential amplifier. By developing Graphical User Interface (GUI) program, we are able to setup detector working parameters configuration, to display real-time counting data and to further meet different application requirements. The fabricated module exhibits good NFAD performance with PDE of 7.9% and 15.8%, DCR of 1.37 kHz and 1.06 kHz and the after-pulse probability of 34.2% and 16.8% at 223 K, 1550 nm with dead time of 200 ns and 1 μs, respectively. It turns out that a near-infrared single photon counting system possessing fast detection speed, fast quenching time, flexible dead time adjustment, small size and high integration will be available in the near future to strongly support lidar and quantum information facilities.
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