Development of InGaAs MPPC for NIR photon counting applications

An InGaAs Multi-Pixel Photon Counter (MPPC) has been developed for detecting the near-infrared and shortwaveinfrared wavelength. Numerous studies were made to develop silicon-based photomultipliers with sensitivity in the nearinfrared region, so they can be applied in various applications such as distance ranging. However, achieving sensitivity at 1.0 μm and longer wavelengths was hard to implement. Therefore a hybrid photon countingdevice was designed by improving the InGaAs avalanche photodiode. In our approach, the sensor layer and the circuit layer are prepared separately, and this configuration brings more flexibility to both layers. The 3x3 pixel matrix and the dedicated circuit were fabricated, and characterizations were performed in terms of the sensitivity uniformity and the other essential parameters of a photon countingdevice such as dark count rate, photon detection probability and so on. An excellent uniformity was observed across the active regions in both a single device and the 3x3 matrix device, which indicated that no any abrupt breakdowns were formed. The DCR was 844 kHz and PDP was 8% under the typical conditions of V e = 1.1 V and T = 253 K. The 3x3 matrix device also exhibited the capability of resolving photon numbers, and the result means this work can be applied to numerous photon-countingapplications in infrared.