Characteristics Of Avalanche Photodiodes Research Articles

Development of the Calibration System and Characterization of the Avalanche Photodiode for Scintillation Detection

Branches of physics and application technologies have widely utilized avalanche photodiodes (APDs) by coupling of scintillators with advantages of multiplication process and effective photosensitivity in a wide range of visible light wavelength. In addition, to meet the requirements for the purpose of each experiment, various types of APDs have been developed. The calibration system and characteristics of APD were constructed and studied by comparing several calibration methods. Electronics calibration is presented with charge injection and quantum efficiency (QE)-calibrated photodiode. By utilizing visible light-emitting diodes (LEDs) and with conventional electronic characteristics and a scintillation crystal with <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">22</sup> Na radioactive source, the APD gain was measured. Furthermore, the following were measured from the calibration method: QE, excess noise factor, and noise level. In this article, we compare our test results with one another, which are provided in the datasheet presented by the manufacturer, and discuss the possibility of standardizing the characterization of APDs by this calibration system.

An Analytic Approach to Study the Effects of Optical Phonon Scattering Loss on the Characteristics of Avalanche Photodiodes

In this paper, we have introduced an efficient analytic approach to study the effects of optical phonon scattering loss on the characteristics of avalanche photodiode (APDs) with multiplication regions as narrow as 25 nm. To do so, we have considered the energy loss caused by collision between carriers and optical phonons. We have also considered the effects of the carrier's dead space and its previous ionization history to develop a new compact model for predicting multiplication gains as well as breakdown conditions in APDs valid for a vast range of temperature. These predicted values can be used to extract carriers' impact ionization coefficients and ionization threshold energies. As an example, we have used our model to predict and extract the aforementioned characteristics and parameters for Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.6</sub> Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.4</sub> As-APDs operating at temperatures over the range of 13 K ¿ T ¿ 290 K. Comparisonof these results with experimental data available in literature has demonstrated the capability of the new developed model as a powerful tool for simulating APDs' behavior and interpreting their experimentally measured characteristics.

A closed-form analytic model to study the characteristics of avalanche photodiodes

In this paper, we introduce for the first time an approximate analytical model that leads to a closed formula to calculate gain, breakdown voltage and excess noise factor of homojunction avalanche photodiodes (APDs) by considering the approximation for dead space. Comparison of our results with experimental data demonstrates that there is an excellent agreement between the results of our calculation and the existing experimental results.

Afterpulsing in Geiger-mode avalanche photodiodes for 1.06μm wavelength

We consider the phenomenon of afterpulsing in avalanche photodiodes (APDs) operating in gated and free-running Geiger mode. An operational model of afterpulsing and other noise characteristics of APDs predicts the noise behavior observed in the free-running mode. We also use gated-mode data to investigate possible sources of afterpulsing in these devices. For 30-μm-diam, 1.06-μm-wavelength InGaAsP∕InP APDs operated at 290K and 4V overbias, we obtained a dominant trap lifetime of τd=0.32μs, a trap energy of 0.11eV, and a baseline dark count rate 245kHz.

Readout of scintillator light with avalanche photodiodes for positron emission tomography

Abstract The noise properties and other relevant characteristics of avalanche photodiodes have been investigated with the perspective of replacing photomultiplier tubes in positron emission tomography. It is clearly demonstrated that they are a valid alternative to photomultiplier tubes in this application.

Avalanche photodiodes with a gain-bandwidth product of more than 200 GHz

The design and characteristics of avalanche photodiodes with a gain-bandwidth product in the range of 250 GHz are reported. The planar front-illuminated silicon diodes are of the n+-p-π-p+ reach-through type.