Efficiency of Solid State Photomultipliers in Photon Number Resolution (original) (raw)
Related papers
Direct photon-counting scintillation detector readout using an SSPM
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2007
Gamma-ray detector technologies, capable of providing adequate energy information, use photomultiplier tubes (PMTs) or silicon avalanche photodiodes to detect the light pulse from a scintillation crystal. A new approach to detect the light from scintillation materials is to use an array of small photon counting detectors, or a "detector-on-a-chip" based on a novel "Solid-state Photomultiplier" (SSPM) concept. A CMOS SSPM coupled to a scintillation crystal uses an array of CMOS Geiger photodiode (GPD) pixels to collect light and produce a signal proportional to the energy of the radiation. Each pixel acts as a binary photon detector, but the summed output is an analog representation of the total photon intensity. We have successfully fabricated arrays of GPD pixels in a CMOS environment, which makes possible the production of miniaturized arrays integrated with the detector electronics in a small silicon chip. This detector technology allows for a substantial cost reduction while preserving the energy resolution needed for radiological measurements.
Advances in CMOS solid-state photomultipliers for scintillation detector applications
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2010
Solid-state photomultipliers (SSPMs) are a compact, lightweight, potentially low-cost alternative to a photomultiplier tube for a variety of scintillation detector applications, including digital-dosimeter and medical-imaging applications. Manufacturing SSPMs with a commercial CMOS process provides the ability for rapid prototyping, and facilitates production to reduce the cost. RMD designs CMOS SSPM devices that are fabricated by commercial foundries. This work describes the characterization and performance of these devices for scintillation detector applications.
Solid-State Photomultiplier In CMOS Technology For Gamma-Ray Detection And Imaging Applications
IEEE Nuclear Science Symposium Conference Record, 2005, 2005
1 -A CMOS solid-state photomultiplier (SSPM) coupled to a scintillation crystal uses an array of CMOS Geiger-mode avalanche photodiode (GPD) pixels to collect light and produce a signal proportional to the energy of the radiation. Each pixel acts as a binary photon detector, but the summed output is an analog representation of the total photon intensity. We have successfully fabricated arrays of GPD pixels in a CMOS environment, which makes possible the production of miniaturized arrays integrated with the detector electronics in a small silicon chip.
Performance Characteristics of the Next Generation Solid-State Photomultipliers
A typical method for detection of radiation consists of using a scintillation material with a photomultiplier tube (PMT), which continues to provide excellent performance in comparison to the solid-state photomultiplier (SSPM). The SSPM has a number of features that makes it a viable alternative, as in being insensitive to magnetic fields, robust, compact, and requiring low voltages for operation, but the major limiting factor associated with a direct replacement for the PMT with SSPMs is the dark current. We will demonstrate a potential, low-cost solution for an upgrade to the PRIMEX experiment at Jefferson Laboratories. We will discuss the characteristics of SSPMs fabricated with commercial and non-commercial CMOS processes. Where the commercial process is reliable but limited in design features, the non-commercial process, which allows for greater control of the design, may have challenges with process control without a dedicated foundry. Fabricated designs show an increase in th...
First results of scintillator readout with silicon photomultiplier
IEEE Transactions on Nuclear Science, 2000
A new type of silicon device has been realized that has many properties comparable to, or better than, a conventional PMT (Photomultiplier Tube). This paper presents the first results of using these photodetectors in place of a PMT in the readout of scintillators for possible PET (Positron Emission Tomography) applications. This device, the Silicon Photomultiplier (SiPM), is effectively an avalanche photodiode operated in Geiger mode. In Geiger-mode detectors, a very large current signal is produced regardless of the size of the input, giving just logical rather than proportional information. However, the SiPM is subdivided into a large number (1440) of microcells that act as independent and virtually identical Geiger-mode photodiodes. The outputs of all these individual microcells are connected so that the total output signal is the sum of the signals from all of the microcells that were activated. In this way proportional information can be obtained. As a consequence of their design, these detectors have potentially very fast timing, high gain (10 5 10 6 ) at low bias voltage ( 50 V), a high quantum efficiency (35% at 500 nm), excellent single photoelectron resolution and are cheap to manufacture. Here we present results obtained with this new photodetector when used with pulsed LED and scintillator pixels.
Characteristics of scintillation detectors based on inorganic scintillators and SiPM light readout
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2013
Recently, a silicon photomultiplier (SiPM) became one of the strongest candidates for application in PET-MR or SPECT-MR dual-modality scanners. However, optimization of the scintillation detectors with SiPM light readout requires different approach than in the case of classic photomultipliers. The finite number of micro-cells in a SiPM creates nonlinear response for high number of incident photons. Moreover, the size and total number of micro-cells defines fill factor, which in turn affects the photon detection efficiency (PDE). Response of SiPMs is also highly sensitive to bias voltage causing changes in PDE and excess noise factor (ENF). Finally, each cell posses an effective dead time needed to fully recharge that cell after the photon detection. In this work the listed above unique features of SiPMs are overviewed. The reported data also contain measurements of energy resolution and 22 Na time resolution.
Journal of Instrumentation, 2006
Properties of a hybrid photodetector (HPD), type PP0275C, produced by Delft Electronic Products B.V., for scintillation detection and spectrometry were studied and compared to a standard XP2020Q photomultiplier. The study was performed for several scintillators, as NaI(Tl), CsI(Tl), and LSO of different dimensions. The excellent capability of the HPD to resolve single photoelectron events was fully confirmed. However, the study of the HPD with the scintillators showed a dramatically reduced number of photoelectrons and a further deterioration of energy resolution, depending on the size (diameter or length) of the crystals. For a 10 mm diameter NaI(Tl) the number of photoelectrons of 5000±250 phe/MeV was measured, which correspond to about 56% of that observed with the XP2020Q with comparable quantum efficiency. Energy resolution of 9.2% for 662 keV γ-rays from a 137 Cs source measured with the HPD light readout showed a serious degradation, larger than that arising from the statistics of photoelectrons. In conclusion, the study showed that this HPD is optimized for single photon detection and its application to scintillation detection is very limited.
A Comprehensive Model of the Response of Silicon Photomultipliers
IEEE Transactions on Nuclear Science, 2000
The response of a silicon photomultiplier (SiPM) to optical signals is inherently nonproportional due to saturation, afterpulsing, and crosstalk. Existing models of the SiPM response do not account for all of these effects, and therefore, these models are not sufficiently accurate for many applications. In this work, a comprehensive model of the SiPM response is developed that is generally applicable to exponentially decaying light pulses and that can be simplified in the case of very short (e.g., laser) light pulses. The model accounts for the total number and the temporal distribution of the incident photons as well as for the relevant SiPM parameters, viz. the recovery time, afterpulsing, crosstalk, and their cross correlations. The model is shown to correspond well with measurements on a SiPM-based scintillation detector. Furthermore, it is shown to be in agreement with several cases for which the SiPM response is known a priori. Having thus validated the model, its use is demonstrated by predicting the response of the Hamamatsu multipixel photon counter (MPPC) S10362-33-050C SiPM to several different scintillators.
IEEE Transactions on Nuclear Science, 2000
Silicon photomultipliers (SiPMs) are expected to replace photomultiplier tubes (PMTs) in several applications that require scintillation detectors with excellent timing resolution, such as time-of-flight positron emission tomography (TOF-PET). However, the theory about the timing resolution of SiPM-based detectors is not yet fully understood. Here we propose a comprehensive statistical model to predict the timing resolution of SiPM-based scintillation detectors. It incorporates the relevant SiPM-related parameters (viz. the single cell electronic response, the single cell gain, the charge carrier transit time spread, and crosstalk) as well as the scintillation pulse rise and decay times, light yield, and energy resolution. It is shown that the proposed model reduces to the well-established Hyman model for timing with PMTs if the number of primary triggers (photoelectrons in case of a PMT) is Poisson distributed and crosstalk and electronic noise are negligible. The model predictions are validated by measurements of the coincidence resolving times (CRT) for 511 keV photons of two identical detectors as a function of SiPM bias voltage, for two different kinds of scintillators, namely LYSO:Ce and LaBr :5%Ce. CRTs as low as ps FWHM for LYSO:Ce and ps FWHM for LaBr :5%Ce were obtained, demonstrating the outstanding timing potential of SiPM-based scintillation detectors. These values were found to be in good agreement with the predicted CRTs of 140 ps FWHM and 95 ps FWHM, respectively. Utilizing the proposed model, it can be shown that the CRTs obtained in our experiments are mainly limited by photon statistics while crosstalk, electronic noise and signal bandwidth have relatively little influence. Index Terms-Gamma ray detection, model, multi pixel photon counter (MPPC), nuclear medicine, positron emission tomography (PET), scintillation counters, silicon photomultiplier (SiPM), time of flight (TOF), timing resolution.