Academic literature on the topic 'Avalanche photodiode operated in Geiger mode'

The collection optics of Thomson scattering systems for plasma devices are designed with maximum possible étendue to keep the required laser energy low. If the spatial resolution along the laser beam is performed by a time-of-flight method, then the detectors, in addition to a large sensitive area, must offer a high frequency bandwidth. Up until now, only microchannel-plate photomultipliers meet these requirements. Here, we investigate the potential use of digital avalanche photodiode arrays operated in the Geiger mode as alternative detectors. In this mode of operation, each array will serve as a fast, sensitive detector. The use of these detectors will lead to significant improvements of the Thomson scattering diagnostic. Most important of these will be a better spatial resolution, down to about 2 cm without deconvolution. Furthermore, the lifetime of the detectors will be increased; the detectors will cover the whole blue wing of the scattered spectrum when using a single wavelength laser, and this will enable measurements of electron temperature and density profiles at kHz repetition rates.

2008/2009
Remarkable interest has recently arisen about the search for Weakly Inter- acting Sub-eV Particles (WISPs), such as axions, Axion Like Particles (ALPs), Minicharged and chameleon particles, all of which are not included in the Stan- dard Model. Precision experiments searching for WISPs probe energy scales as high as 10^6 TeV and are complementary to accelerator experiments, where the energy scale is a few TeV. The axion, in particular, is the oldest studied and has the strongest theoretical motivation, having its origin in Quantum Chromodynamics. It was introduced for the first time in 1973 by Peccei and Quinn to solve the strong CP problem, while later on the cosmological implications of its postulated existence also became clear: it is a good candidate for the cold dark matter, and it is necessary to fully explain the evolution of galaxies. Among the different interactions of axions, the most promising for its detection, from an experimental point of view, is the coupling to two photons (Primakoff effect). Using this coupling, several bounds on the axion mass and energy scale have been set by astrophysical observations, by laboratory experiments and by the direct observation of celestial bodies, such as the Sun. Most of these considerations, as was recently recognized, not only constrain the mass and coupling of the axion, but are more generally applicable to all ALPs. The current best limits on the coupling, over a wide range of ALP masses, come from the the CAST (Cern Axion Solar Telescope) experiment at Cern, which looks for ALPs produced in the solar core. The experiment is based on the Primakoff effect in a high magnetic field, where solar ALPs can be reconverted in photons. The CAST magnet, a 10 T, 10 m long LHC superconducting dipole, is placed on a mobile platform in order to follow the Sun twice a day, during sunrise and sunset, and has two straight bores instrumented with X-ray detectors at each end. The re- generated photon flux is, in fact, expected to be peaked at a few keV. On the other hand, there are suggestions that the problem of the anomalous temperature profile of the solar corona could be solved by a mechanism which could enhance the low energy tail of the regenerated photon spectrum. A low energy photon counter has, for this reason, been designed and built to cover one of the CAST ports, at least temporarily. Low energy, low background photon counters such as the one just mentioned, are also crucial for most experiments searching for WISPs. The low energy photon counting system initially developed to be coupled to CAST will be applicable, with proper upgrades, to other WISPs search experiments. It consists of a Galilean telescope to match the CAST magnet bore cross section to an optical fiber leading photons to the sensors, passing first through an optical switch. This last device allows one to share input photons between two different detectors, and to acquire light and background data simultaneously. The sensors at the end of this chain are a photomultiplier tube and an avalanche photodiode operated in Geiger mode. Each detector was preliminary characterized on a test bench, then it was coupled to the optical system. The final integrated setup was subsequently mounted on one of the CAST magnet bores. A set of measurements, including live sun tracking, was carried out at Cern during 2007-2008. The background ob- tained there was the same measured in the test bench measurements, around 0.4 Hz, but it is clear that to progress from these preliminary measurements a lower background sensor is needed. Different types of detectors were considered and the final choice fell on a Geiger mode avalanche photodiode (G-APD) cooled at liquid nitrogen temperature. The aim is to drastically reduce the dark count rate, al- though an increase in the afterpulsing phenomenon is expected. Since the detector is designed to be operated in a scenario where a very low rate of signal photons is predicted, the afterpulsing effect can be accepted and corrected by an increase in the detector dead time. First results show that a reduction in background of a factor better than 10^4 is obtained, with no loss in quantum e ciency. In addition, an optical system based on a semitransparent mirror (transparent to X-rays and re ective for 1-2 eV photons) has been built. This setup, covering the low energy spectrum of solar ALPs, will be installed permanently on the CAST beamline. Current work is centered on further tests on the liquid nitrogen cooled G-APD concept involving different types of sensors and different layouts of the front-end read-out electronics, with a particular attention to the quenching cir- cuit, whether active or passive. Once these detector studies are completed, the final low background sensor will be installed on the CAST experiment. It is important to note that the use of a single photon counter for low energy photons having a good enough background (<1 Hz at least) is not limited to the CAST case, but is of great importance for most WISPs experimental searches, with special regard for photon regeneration experi- ments, and, in general, for the field of precision experiments in particle physics.
Negli ultimi tempi è riemerso un notevole interesse nel campo della ricerca di particelle leggere debolmenti interagenti (Weakly Interacting Sub-eV Particles - WISPs), come ad esempio assioni, particelle con comportamenti simili agli assioni (Axion Like Particles - ALPs), particelle con carica frazionaria e particelle camaleonte; tutti tipi di particelle non inclusi nel Modello Standard. Vista la loro natura debolmente interagente, la scala di energia coinvolta è dell'ordine dei 10^6 TeV, queste particelle non sono visibili nelle collisioni realizzabili negli attuali acceleratori e possono invece essere studiate in esperimenti di precisione, che, sotto questo punto di vista, diventano complementari agli esperimenti su acceleratori. L'assione in particolare è la prima particella, da un punto di vista cronologico, ad essere stata ipotizzata, ed inoltre la sua esistenza è supportata da forti basi teoriche: la sua origine va infatti ricercata all'interno della Cromodinamica Quantistica (QCD). L'assione fu introdotto per la prima volta nel 1973 da Peccei e Quinn come soluzione del problema di violazione di CP nelle interazioni forti, mentre le sue implicazioni cosmologiche risultarono chiare solo in seguito. L'assione infatti può essere considerato un buon candidato per la materia oscura fredda e la sua introduzione è necessaria per spiegare l'evoluzione delle galassie. Tra le diverse interazione degli assioni con la materia e la radiazione, la più interessante da un punto di vista sperimentale è l'accoppiamento con due fotoni (effetto Primakoff). Usando questo tipo di accoppiamento numerosi limiti, sia sulla massa dell'assione che sulle scale di energia coinvolte, possono essere ottenuti da osservazioni astrofisiche e da esperimenti di laboratorio così come dalla diretta osservazione di oggetti celesti tipo il Sole. Queste considerazioni possono essere applicate non solo all'assione ma più in generale a tutte le ALPs. Attualmente i limiti migliori sulla costante di accoppiamento, su un largo spettro di masse di ALPs, si sono ottenuti dall'esperimento CAST (Cern Axion Solar Tele- scope) al Cern, che guarda agli ALPs prodotti nel Sole. L'esperimento è basato sull'effetto Primakoff in un campo magnetico elevato, dove gli ALPs solari sono riconvertiti in fotoni. Il magnete dell'esperimento CAST è costituito da un prototipo per un dipolo superconduttore di LHC, lungo 10 m e con un campo magnetico totale di 10 T. Il magnete è posto su di un affusto mobile per poter seguire il sole durante le fasi di alba e tramonto. Alle due estremità del magnete sono disposti quattro rivelatori sensibili nel campo degli X molli. Il picco del usso di fotoni rigenerato è infatti atteso a pochi keV. Tuttavia, ci sono suggerimenti che il prob- lema ancora aperto del profilo di temperatura della corona solare può essere risolto tramite un meccanismo che contemporaneamente incrementerebbe le code a bassa energia dell'atteso usso di fotoni rigenerati. A questo scopo un contatore di fotoni sensibile nell'intervallo del visibile è stato progettato ed assemblato per coprire una delle quattro porte del magnete di CAST, almeno temporaneamente. I contatori di fotoni studiati hanno un largo campo di applicazione e possono essere usati in altri tipi di esperimenti per la ricerca di WISPs. Il sistema inizialmente sviluppato per CAST consiste in un telescopio Galileiano per accoppiare una fibra ottica all'apertura del magnete di CAST, la fibra ottica è quindi collegata ad un interruttore ottico che permette di utilizzare due rivelatori contemporaneamente. La fibra in ingresso è infatti collegata alternativamente a due fibre in uscita, in questo modo ciascun rivelatore acquisisce per metà del tempo segnale e per metà del tempo fondo, lasciando inalterato il tempo totale di integrazione. I sensori utilizzati fino ad ora al termine della catena ottica sono un tubo fotomoltiplicatore e un avalanche photodiode operato in modalità Geiger. Ciascun rivelatore è stato preliminarmente caratterizzato su un banco di prova e quindi collegato al sistema ottico. Il sistema finale è stato quindi installato su CAST. Una serie di misure, che includono reali prese dati, sono state condotte al Cern durante il 2007-2008. La misura del fondo ottenuta a CAST è stata la stessa misurata durante i test di prova a Trieste, circa 0.4 Hz, ma risulta chiaro che il vero sviluppo futuro è basato su un sensore a fondo molto più basso. A questo scopo sono stati considerati diversi tipi di sensore e la scelta finale è ricaduta su di un avalanche photodiode operato in modalità Geiger e raffreddato all'azoto liquido. Lo scopo è quello di ridurre drasticamente i conteggi di fondo, sebbene a queste temperature sia atteso un incremento del rateo di afterpulses. Tuttavia il rivelatore è pensato per essere utilizzato in un applicazione a basso rateo e quindi il fenomeno degli afterpulses può essere ridotto agendo direttamente sul tempo morto del rivelatore, cioè aumentandolo. I primi test condotti sul rivelatore mostrano un decremento del fondo pari ad un fattore meglio di 10^4, senza rilevabili variazioni in efficienza. In aggiunta a questo sistema, per ottenere un'installazione permanente sul fascio di CAST, è stato realizzato uno specchio semitrasparente, che lascia pressocchè inalterato il fascio di raggi X e invece de ette il fascio di fotoni con energia nel visibile. Il lavoro attuale è incentrato sullo sviluppo del rivelatore a basso fondo raffreddato all'azoto liquido, includendo anche lo studio di diversi tipi di sensore e diversi tipi di elettronica di lettura, con particolare attenzione all'elettronica di quenching del circuito con le varianti attiva e passiva. Una volta terminati gli studi sui diversi tipi di rivelatori, l'apparato finale sarà installato su CAST. E' comunque importante notare che l'uso di un rivelatore a singolo fotone sensibile tra 1-2 eV con un fondo sufficientemente basso (<1 Hz almeno) non è limitato all'uso su CAST ma in tutti gli altri esperimenti per la ricerca di WISPs, con particolare riguardo agli esperimenti di rigenerazione risonante, e in generale, nel campo di applicazione degli esperimenti di precisione alla fisica delle particelle.
1982

The next generation of particle colliders will be characterized by linear lepton colliders, where the collisions between electrons and positrons will allow to study in great detail the new particle discovered at CERN in 2012 (presumably the Higgs boson). At present time, there are two alternative projects underway, namely the ILC (International Linear Collider) and CLIC (Compact LInear Collider). From the detector point of view, the physics aims at these particle colliders impose such extreme requirements, that there is no sensor technology available in the market that can fulfill all of them. As a result, several new detector systems are being developed in parallel with the accelerator. This thesis presents the development of a GAPD (Geiger-mode Avalanche PhotoDiode) pixel detector aimed mostly at particle tracking at future linear colliders. GAPDs offer outstanding qualities to meet the challenging requirements of ILC and CLIC, such as an extraordinary high sensitivity, virtually infinite gain and ultra-fast response time, apart from compatibility with standard CMOS technologies. In particular, GAPD detectors enable the direct conversion of a single particle event onto a CMOS digital pulse in the sub-nanosecond time scale without the utilization of either preamplifiers or pulse shapers. As a result, GAPDs can be read out after each single bunch crossing, a unique quality that none of its competitors can offer at the moment. In spite of all these advantages, GAPD detectors suffer from two main problems. On the one side, there exist noise phenomena inherent to the sensor, which induce noise pulses that cannot be distinguished from real particle events and also worsen the detector occupancy to unacceptable levels. On the other side, the fill-factor is too low and gives rise to a reduced detection efficiency. Solutions to the two problems commented that are compliant with the severe specifications of the next generation of particle colliders have been thoroughly investigated. The design and characterization of several single pixels and small arrays that incorporate some elements to reduce the intrinsic noise generated by the sensor are presented. The sensors and the readout circuits have been monolithically integrated in a conventional HV-CMOS 0.35 μm process. Concerning the readout circuits, both voltage-mode and current-mode options have been considered. Moreover, the time-gated operation has also been explored as an alternative to reduce the detected sensor noise. The design and thorough characterization of a prototype GAPD array, also monolithically integrated in a conventional 0.35 μm HV-CMOS process, is presented in the thesis as well. The detector consists of 10 rows x 43 columns of pixels, with a total sensitive area of 1 mm x 1 mm. The array is operated in a time-gated mode and read out sequentially by rows. The efficiency of the proposed technique to reduce the detected noise is shown with a wide variety of measurements. Further improved results are obtained with the reduction of the working temperature. Finally, the suitability of the proposed detector array for particle detection is shown with the results of a beam-test campaign conducted at CERN-SPS (European Organization for Nuclear Research-Super Proton Synchrotron). Apart from that, a series of additional approaches to improve the performance of the GAPD technology are proposed. The benefits of integrating a GAPD pixel array in a 3D process in terms of overcoming the fill-factor limitation are examined first. The design of a GAPD detector in the Global Foundries 130 nm/Tezzaron 3D process is also presented. Moreover, the possibility to obtain better results in light detection applications by means of the time-gated operation or correction techniques is analyzed too.
Aquesta tesi presenta el desenvolupament d’un detector de píxels de GAPDs (Geiger-mode Avalanche PhotoDiodes) dedicat principalment a rastrejar partícules en futurs col•lisionadors lineals. Els GAPDs ofereixen unes qualitats extraordinàries per satisfer els requisits extremadament exigents d’ILC (International Linear Collider) i CLIC (Compact LInear Collider), els dos projectes per la propera generació de col•lisionadors que s’han proposat fins a dia d’avui. Entre aquestes qualitats es troben una sensibilitat extremadament elevada, un guany virtualment infinit i una resposta molt ràpida, a part de ser compatibles amb les tecnologies CMOS estàndard. En concret, els detectors de GAPDs fan possible la conversió directa d’un esdeveniment generat per una sola partícula en un senyal CMOS digital amb un temps inferior al nanosegon. Com a resultat d’aquest fet, els GAPDs poden ser llegits després de cada bunch crossing (la col•lisió de les partícules), una qualitat única que cap dels seus competidors pot oferir en el moment actual. Malgrat tots aquests avantatges, els detectors de GAPDs pateixen dos grans problemes. D’una banda, existeixen fenòmens de soroll inherents al sensor, els quals indueixen polsos de soroll que no poden ser distingits dels esdeveniments reals generats per partícules i que a més empitjoren l’ocupació del detector a nivells inacceptables. D’altra banda, el fill-factor (és a dir, l’àrea sensible respecte l’àrea total) és molt baix i redueix l’eficiència detectora. En aquesta tesi s’han investigat solucions als dos problemes comentats i que a més compleixen amb les especificacions altament severes dels futurs col•lisionadors lineals. El detector de píxels de GAPDs, el qual ha estat monolíticament integrat en un procés HV-CMOS estàndard de 0.35 μm, incorpora circuits de lectura en mode voltatge que permeten operar el sensor en l’anomenat mode time-gated per tal de reduir el soroll detectat. L’eficiència de la tècnica proposada queda demostrada amb la gran varietat d’experiments que s’han dut a terme. Els resultats del beam-test dut a terme al CERN indiquen la capacitat del detector de píxels de GAPDs per detectar partícules altament energètiques. A banda d’això, també s’han estudiat els beneficis d’integrar un detector de píxels de GAPDs en un procés 3D per tal d’incrementar el fill-factor. L’anàlisi realitzat conclou que es poden assolir fill-factors superiors al 90%.

La genèse des travaux présentés dans ce mémoire se situe dans le domaine de l'astrophysique des très hautes énergies. Il y a un siècle les scientifiques de la planète ont identifié un nouveau type de messagers venant de l'espace : les rayons cosmiques. Ce rayonnement est constitué de particules (photons et autres) de très haute énergie qui bombardent la terre en permanence. Le passage de rayonnements cosmiques dans l'atmosphère terrestre se traduit par la génération de brefs éclairs lumineux (5ns) d'une intensité très faible (1pW) : le flash Tcherenkov, devenant alors visible du sol.

Dans l'état de l'art le meilleur détecteur de lumière est aujourd'hui le Photomultiplicateur (PMT), grâce à ses caractéristiques de sensibilité et de vitesse. Mais il présente quelques inconvénients : faible efficacité quantique, coût, poids etc. Nous présentons dans cette thèse une nouvelle technologie alternative : les compteurs de photons sur semi-conducteur, constitués de photodiodes polarisées en mode Geiger.
Ce mode de fonctionnement permet d'obtenir un effet de multiplication au moins identique à celui des PMT. Un modèle physique et électrique a été développé pour reproduire le comportement de ce détecteur.
Nous présentons ensuite dans ce travail de thèse un procédé technologique original permettant la réalisation de ces dispositifs dans la centrale de technologie du LAAS-CNRS, avec la simulation de chaque opération du processus.
Nous avons mis au point une fiche pour la caractérisation électrique des dispositifs, du mode statique au mode dynamique, et vérifié la conformité aux simulations SILVACO, et au modèle initial. Les résultats obtenus sont déjà excellents, compte tenu qu'il s'agit d'une première étape de prototypage, et comparables avec les résultats publiés dans la littérature.
Ces composants sur silicium peuvent intervenir dans toutes les applications où il y a un photomultiplicateur, et le remplacer. Les applications sont donc très vastes et la croissance du marché très rapide. Nous présentons une première expérience d'astrophysique installée au Pic du Midi qui a détecté des flashs Tcherenkov de rayons cosmiques avec cette nouvelle technologie à semi-conducteur.

Ce travail porte sur la modélisation pour la simulation et la prédiction desparamètres de performance des photodiodes à avalanche polarisée en mode Geiger en technologieCMOS, ou SPADs CMOS, pour Lidars spatiaux. Ce travail de thèse vise à développerune méthodologie basée sur : des modèles de la physique du semi-conducteur, des mesuresfournissant des informations sur le procédé technologique visé et des outils commerciaux desimulation. Ceci, dans le but de simuler les paramètres de performance des SPADs en serapprochant autant que possible de la réalité du procédé technologique afin d’améliorer lesprédictions. Des SPADs ont été conçues et caractérisées de manière à acquérir les paramètresde performances et les confronter aux résultats de simulation pour valider notre approche.De plus, la conception des SPADs s’est faite en regard des spécifications Lidar du CNESet d’Airbus Defence and Space en vue d’obtenir des structures permettant d’améliorer nosconnaissances en matière de : compréhension des mécanismes physiques, conception et méthodede caractérisation des SPADs CMOS. Ceci, dans l’intention d’étudier la possibilitéd’intégrer ces détecteurs dans leurs futurs systèmes Lidars spatiaux
This work focuses on modelling for simulation and prediction purposes ofCMOS SPADs performance parameters used in spaceborne Lidars. The innovative side ofthis work lies in a new methodology based on physical models for semiconductor devices,measurements performed on the targeted CMOS process and commercial simulation tools topredict CMOS SPADs performances. This method allows to get as close as possible to theprocess reality and to improve predictions. A set of SPAD has been designed and fabricated,and is used for measurements and model validation. SPAD design has been done with respectto CNES and Airbus Defence Space Lidar specification, in order to produce devices that willimprove our knowledge in terms of understanding of the involved physical mechanisms, SPADsdesign and test method, for a possible integration within their future spaceborne Lidars

Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Shen, Shyh-Chiang; Committee Member: Doolittle, William A.; Committee Member: Dupuis, Russell Dean. Part of the SMARTech Electronic Thesis and Dissertation Collection.

碩士
國立臺灣大學
電子工程學研究所
107
This thesis is divided into two parts to discuss the Avalanche Photodiode(APD). The front part analyses the electrical properties of the planer-type InP/InGaAs SAGCM (Separate Absorption, Grading, Charge, and Multiplication) APD. The measurement includes current-voltage analysis, capacitance-voltage analysis, and the effect of temperature variation on device. And we also discuss the influence on punch-through voltage and breakdown voltage with different pattern parameters. From the result of current-voltage measurement, when there is no spacing between the guard ring and the active region, the punch-through voltage is the smallest, the breakdown voltage is the biggest, and the dark current before breakdown is larger than others. It is also known form variable temperature current-voltage measurement that the main source of the dark current is generation-recombination current from InGaAs absorption layer, and the higher the temperature, the larger the breakdown voltage. The latter part is the measurement of Geiger-mode Si-APD operates on Passive Quenching Circuit(PQC). And we measure the real breakdown voltage and APD internal resistance with PQC. At last, we also propose the place where traditional PQC model needs to be modified.

碩士
國立臺北科技大學
光電工程系
106
In this thesis, the changing in temperature, excess bias and gated frequency to detect single photon using a dual avalanche photodiode (APD) scheme was proposed and demonstrated. The characteristics of single photon detection, including dark count probability (DCP), single photon detection efficiency (SPDE), noise equipment power (NEP) and afterpulsing probability, are measured and discussed. In this work, APD1 was cooled down by TE cooler and operated excessed breakdown voltage. APD2 was operated in room temperature and bias act a proper voltage to match APD1. Then, the signals of APD1 and APD2 were self-differencing to reduce spiking noise and avalanche signal can be easy detected. Finally, the avalanche signals are observed by scope or recorded by photon counter. Temperature of -30°C, gated frequency of 1 MHz, gated pulse of 2 ns and excess bias of 3.2 V, the best single-photon performances. In this study are : dark count probability of 2.48×10-3, single photon detection efficiency of 12.86 %, noise equipment power of 1.56×10-15 (W/Hz)1/2 and afterpulsing probability of 5.67 %.

The Antarctic Miniature Lidar (AML) instrument has been assembled, tested, and deployed to the NOAA Clean Air Facility at the Amundsen-Scott South Pole Station. AML uses redundant commercially available, single element semiconductor lasers, operated CW, and a silicon avalanche photodiode (APD) operated in the Geiger or photon counting mode. We present preliminary lidar measurements made at both Goddard Space Flight Center, prior to deployment, and at the Clean Air Facility after installation at the South Pole Station in early February, 1995.

Useful photon-counting and correlation properties of Si APD's in sub-geiger mode are described, with potential of high quantum efficiency and ultralow afterpulsing in an alternative single-photon-counting array detector.