A Comprehensive Study, Characterization & Simulation of Silicon Photo Multiplier:A New Device for Low Light Detection

In recent years, a new kind of semiconductor detector called SiPM has been developed to detect a single optical photon as an alternative to PMT & APD. SiPM have many advantages in terms of very fast timing response, high gain at low bias voltage, low power consumption, good temperature to voltage stability, insensitive to magnetic fields. Reliability, ruggedness, compactness, no excess light damages and long life span are our favorable characteristics. This device SiPM is a promising to find wide spread uses in nuclear medical imaging application, Environmental chemical, high energy physics and many other fields. Silicon photomultipliers are Silicon single photon sensitive devices built from an avalanche photodiode (APD) array on common Si substrate. The idea behind this device is the detection of single photon events in sequentially connected Si APDs. The dimension of each single APD can vary from 20 to 100 micrometers, and their density can be up to 103/mm2. Every APD in SiPM operates in Geiger-mode and is coupled with the others by a polysilicon quenching resistor. Although the device works in digital/switching mode, the SiPM is an analog device because all the microcells are read in parallel making it possible to generate signals within a dynamic range from a single photon to 1000 photons for just a single square millimeter area device. The supply voltage (Vb) depends on APD technology used, and typically varies between 25 V and 70 V, thus being from 30 to 50 times lower than the voltage required for a traditional photomultiplier tubes (PMTs) operation. SiPM has been invented in Russia in Moscow Engineering Physics Institute. This design idea was then used with some variations by SensL, Photonique, Hamamatsu, KETEK, Voxtel Inc.