Research On The Miniature Single Photon Detection Module Based On InGaAs(P)/InP Single Photon Avalanche Photodiode

Lidar has been widely used in the fields of surveying and mapping,autonomous driving and remote sensing.In high-performance lidar systems,by introducing single-photon detection technology,the power of active illumination can be reduced,the load weight and power consumption can be effectively reduced,and the working distance can be increased.Different application scenarios have very different requirements for the performance,working conditions,and volume power consumption of single-photon detectors.In order to meet the integrated single-point or multi-beam lidar application requirements of volume-constrained systems such as unmanned platforms,this paper developed a miniaturized single-photon detector based on InGaAsP/InP SPAD,and tested and analyzed its performance.And carried out the dual-channel integrated free-running single-photon detector research based on domestic InGaAsP/InP SPAD to achieve more integrated detection components and improve its ease of use in the field of lidar.The main research contents are as follows:In order to overcome the differential interference signal generated by the distributed capacitance and junction capacitance of the avalanche photodiode,a capacitance balance method is designed.By adding an RC circuit to the balance circuit,over-balance is achieved,and the amplitude and duration of the spikes reaching the reverse input of the avalanche comparator are increased,so that the tolerance of the entire circuit to the residual spike noise is greatly improved.The minimum avalanche discrimination level that can be set outside the noise relaxation time is reduced,and the discrimination level is reduced from 5.8 mV to 2.4 mV.While effectively reducing the avalanche pulse duration,the detector's extraction efficiency for weak avalanche signals is further improved.In order to reduce the quenching time of SPAD and obtain better performance of the detector,an active quenching recovery circuit with ultra-low delay is designed.The quenching delay is reduced to 400 ps,which is about 20%lower than before.And successfully developed a free-running single-photon detector based on InGaAsP/InP SPAD.For light with a wavelength of 1060 nm,under the conditions of a temperature of-30?,a detection efficiency of 20%,and a dead time of 1 ?s,the post-pulse probability is only It is 11.8%,the dark count rate is about 2?5 kHz,the shortest dead time is 50 ns,and the maximum detection efficiency can reach 30%.The comprehensive performance exceeds other current free-running single-photon detectors based on InGaAsP/InP SPAD.In order to realize the miniaturization of the detector,its application on the movable carrier is more portable and stable.By optimizing the integrated packaging of SPAD,key components such as balance circuit,temperature measuring resistor,TEC and SPAD chip are integrated and packaged.The optimized package structure makes the SPAD and the balanced capacitor circuit share similar electromagnetic environment and distribution parameters,and reduces the power consumption of the detector from about 60 W in the past to about 6 W,realizing the low power consumption of the detector and the lowest cooling temperature It can reach-35?.The overall size of the detector is reduced to 63 mm×54 mmx44 mm,which is the smallest size of the same type of detector currently known in the world.In order to achieve the high performance and integration of the multi-element detector and make it more suitable for multi-beam lidar applications under the condition of limited system volume,an integrated dual-channel single-photon detector based on domestic InGaAs(P)/InP SPAD has been developed.By optimizing the detector's recovery circuit and avalanche extraction circuit,designing a new type of refrigeration control technology and designing a new type of circuit board,the size of the detector's circuit module is reduced to 44 mm×28 mm.The available dead time of the detector is 100 ns.At-30?,the detection efficiency is about 11.4%,and the dead time is 1 ?s,the post-pulse probability is about 18.7%,and the dark count rate is about 20 kHz.The two-channel detectors can perform good detection at the same time.