Programmable, Reconfigurable Silicon Photodiode Array Module

Many planned nextgeneration experiments in high energy physics, astroparticle physics, and nuclear physics need a plethora of photon detectors with singlephoton sensitivity, large dynamic range, and accessibility throughout experiment lifetime. These requirements constrain the sensor: low sensitivity against temperature and bias fluctuations; very compact; very robust; cheap; insensitive to magnetic fields; no aging over years; radiation hard; very low response to passing ionizing particles (low nuclear counter effect). Silicon photomultiplier are promising photon detectors. Also called Geigermode avalanche photodiode, single photon avalanche photodiodes, or micropixel avalanche photon detectors, benefits of solidstate silicon photomultiplier detectors are largely demonstrated with limited applicationspecific functionality. Most single photon applications require precise timing, event counting, and precise x/y coordinate resolution. These requirements introduce significant systemdesign challenges: Reading out data from every channel becomes intractable in systems with tens of thousands of parallel channels. Moreover, required inpixel functionality reduces sensitive area and introduces incompatible semiconductor processing requirements. A camera systeminapackage is developed that efficiently partitions pixelated detector array functions. Using vertical stacking of reconfigurable logic (fieldprogrammable gate array) and processors, made using lowpower, highdensity, costeffective 28nm CMOS to allow many hundreds of inputoutput connects, it is possible to develop a robust, reconfigurable imager, programmable for efficient implementation of applicationspecific functions. This reduces cost and risk of designing deepsubmicron detector arrays with circuit functions that encroach on the detector area, reducing fill factor. Programmability provides flexibility, enabling multigenerational singlephoton avalanche photodiode designs to be implemented, readily configured for experiments, and adapted to various data transmission formats. A camera systeminapackage architecture is developed, including a bare die fieldprogrammable gate array, a glass or silicon interposer board, and a simple CMOS readout circuit, containing only the basic functions of a single photon avalanche photodiode, including pixel enable/disable, activequenching circuits, and unit cell routing and interconnections. The singlephoton avalanche photodiode can be programmed to be processed in 512 parallel processing channels. The systeminapackage is designed and electrically and thermally modeled, and a manufacturing flow is defined. Capability of timestamping, timeoverthreshold, multiple timeoverthreshold encoding on 512 parallel channels with 30picosecond time resolution, and realtime auto and crosscorrelation will be shown. Commercial Applications and Other Benefits: Highly functional singlephoton detectors are needed for a variety of nuclear and particle physics experiments, biomedical imaging devices such as positron emission tomography imaging systems and Xray imaging devices, human computer and gesture recognition devices, and for military 3D imaging applications.