Study On Geiger Mode Single Photon Avalanche Diode Pixel Circuit Based On CMOS Technology

Single photon detection technology has wide application prospect in theconstruction of national defense, industrial and civil life field, such as: DNA sequencingand fluorescence lifetime imaging in the biology, radar ranging and deep sea explorationin the military, exploration of outer space and3D vision system in the astronomy,particle image velocimetry and quantum cryptography in the physics, instantaneous gasimaging and iron concentration in the chemistry, and so on. Single photon avalanchediodes based on the CMOS technology is acted as the core device inner the photondetectors, which is becoming more and more focused and valued by the researchers.This paper that is supported by the central colleges and universities scientificresearch basic business funding, referenced to the single photon avalanche diode devicestructure at home and abroad, designed single photon avalanche diode(SPAD) devicestructure with the p+/n-planar structure as the active region and with deep p-well as theguard ring. Using Atlas tool realized the device structure design, and simulated theseparameters of the SPAD, such as: avalanche breakdown voltage, electric field intensity,impact generation rate, dark current, light current, avalanche generation rate of carriers,current density and current flowing and so on. Simulation results of these parametersshow that the structural design of the device is meet the prior designing requirements.The paper introduced the main characteristic parameters of the SPAD in the Geigermode: photon detection efficiency, dark count rate, jitter(time resolution), after pulserate, sensitivity and bandwidth. after deep analysis and comparison of the principle anddifferences among the various quenching and resetting circuits, this paper designed theactive quenching and recharging circuit for pixel circuit. Adopting the monostabletrigger combined with the tube switch and the parasitic capacitance of diode depletionlayer, the parasitic junction capacitance of diode, the breakdown voltage source of diode,the body resistance of diode built the Spice mode of SPAD and simulated. Simulationresults show that the gate signal of switch tube will not suffer to be influenced by thefalling edge of pulse high level, reflected an independent feedback process. Using theCMOS technology of the0.5μm DPTM designed quenching and resetting circuit,completed the simulation of circuit, drawed layout.