Development of silicon hybrid SPAD 1D arrays for lidar and spectrometer applications

The MPPC, a sort of silicon photomultiplier, has good photon-counting ability and timing accuracy. Recently, a new type of MPPC that has excellent sensitivity in the green region or near-infrared, wide dynamic range, higher photon detection efficiency, and various format configurations (single channel and 1D array) was developed. To utilize its advantageous performance, dedicated readout electronics is required. For LIDAR applications, the red-enhanced MPPC can be used, and the functional for the readout system are estimating the number of photons and recording the precise time-of-arrival. For these requirements, a time-over-threshold circuit that can recognize the incoming energy down to 1 photon and a time-to-digital converter that can record time-of-arrival with 312ps resolution were integrated onto a single die. We have demonstrated that the system has the capability to measure distance with centimeter accuracy. For situations that require higher dynamic range, a high-speed comparator and counter array configuration can be provided. For weak-light-level applications like spectroscopy, a configuration consisting of a SPAD 1D array, active quenching circuit and gate function can be used. We will propose a 1D hybrid SPAD that is the optimal combination for various applications.