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What is SiPM? What is SPAD?
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Author : JIUZHOU
Update time : 2024-09-13 09:11:10
SiPM (Silicon photomultiplier) and SPAD(Single Photon Avalanche Diode), what are these two devices? This article will answer your questions.
SiPM (Silicon photomultiplier)
Definition: Silicon photomultiplier, referred to as SiPM, HAMAMATSU is called MPPC (multi-pixel photon counter) according to the principle. It is a new type of photodetector.
It consists of an avalanche diode array that works in Geiger mode. This setup has high gain and high sensitivity. It also uses low bias voltage and is not affected by magnetic fields. Additionally, it has a compact structure.
It was invented in the late 1990s and is widely used in high-energy physics and nuclear medicine (PET) and other fields. In recent years, nuclear medicine has grown quickly. It is seen as the future for very weak light detectors.
Structure: The most basic unit of MPPC is composed of an APD in Geiger mode and a quenching resistor in series, which are combined to form a pixel. Silicon photomultiplier tubes are composed of a large number of such pixels arranged in two dimensions.
SPAD (Single Photon Avalanche Diode)
Definition: SPAD (Single Photon Avalanche Diode) is a photodetection avalanche diode with single photon detection capability. It works in Geiger mode, that is, when the operating voltage is higher than its avalanche breakdown voltage. It uses the avalanche breakdown phenomenon to achieve single photon detection capability.
SPAD often has high photon detection efficiency and a wide range of spectral response. It is very sensitive and uses little power. These features make it useful in many fields.
Structure: The working principle of SPAD is based on the Geiger mode. In this mode, when a photon is absorbed by the SPAD, an electron-hole pair is generated.
If this electron-hole pair gets enough energy from the electric field, it will cause an avalanche effect.
This will cause a sharp increase in current, thereby realizing the detection of a single photon. This effect allows SPAD to function in very low light. It can even detect one single photon.
SiPM (Silicon photomultiplier)
Definition: Silicon photomultiplier, referred to as SiPM, HAMAMATSU is called MPPC (multi-pixel photon counter) according to the principle. It is a new type of photodetector.
It consists of an avalanche diode array that works in Geiger mode. This setup has high gain and high sensitivity. It also uses low bias voltage and is not affected by magnetic fields. Additionally, it has a compact structure.
It was invented in the late 1990s and is widely used in high-energy physics and nuclear medicine (PET) and other fields. In recent years, nuclear medicine has grown quickly. It is seen as the future for very weak light detectors.
Structure: The most basic unit of MPPC is composed of an APD in Geiger mode and a quenching resistor in series, which are combined to form a pixel. Silicon photomultiplier tubes are composed of a large number of such pixels arranged in two dimensions.
SPAD (Single Photon Avalanche Diode)
Definition: SPAD (Single Photon Avalanche Diode) is a photodetection avalanche diode with single photon detection capability. It works in Geiger mode, that is, when the operating voltage is higher than its avalanche breakdown voltage. It uses the avalanche breakdown phenomenon to achieve single photon detection capability.
SPAD often has high photon detection efficiency and a wide range of spectral response. It is very sensitive and uses little power. These features make it useful in many fields.
Structure: The working principle of SPAD is based on the Geiger mode. In this mode, when a photon is absorbed by the SPAD, an electron-hole pair is generated.
If this electron-hole pair gets enough energy from the electric field, it will cause an avalanche effect.
This will cause a sharp increase in current, thereby realizing the detection of a single photon. This effect allows SPAD to function in very low light. It can even detect one single photon.
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