Dissertations / Theses: 'Diodes à avalanche à photon unique'

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Bérubé, Benoît-Louis. "Conception de matrices de diodes avalanche à photon unique sur circuits intégrés CMOS 3D." Thèse, Université de Sherbrooke, 2014. http://savoirs.usherbrooke.ca/handle/11143/92.

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La photodétection est un sujet de recherche très actif encore de nos jours et l’industrie, particulièrement de la physique des hautes énergies et de l’imagerie médicale, est en quête de détecteurs avec une plus grande sensibilité, de meilleures résolutions temporelles et une plus grande densité d’intégration. Pour ces raisons, les photodiodes avalanche à photon unique (Single photon avalanche diode, ou SPAD) suscitent beaucoup d’intérêt depuis quelques années pour ses performances en temps et sa grande photosensibilité. Les SPAD sont des photodiodes avalanche opérées au-dessus de la tension de claquage et un photoporteur atteignant la région de multiplication peut à lui seul déclencher une avalanche soutenue de porteurs et entraîner le claquage de la jonction. Un circuit détecte le courant divergent et l’étouffe en abaissant la polarisation de la jonction sous la tension de claquage. Le circuit recharge ensuite la jonction en réappliquant la tension initiale permettant la détection d’un nouveau photon. Dans le but d’augmenter le nombre de photons simultanés détectables, les SPAD s’intègrent en matrice. Cependant, dans le cas où une matrice de SPAD et leurs circuits d’étouffement s’intègrent sur le même substrat, la surface photosensible devient limitée par l’espace qu’occupent les circuits d’étouffement. Dans le but d’augmenter leur région photosensible, les matrices de SPAD peuvent s’intégrer en trois dimensions (3D) avec leurs circuits d’étouffement. Ce projet porte sur le développement de matrices de SPAD en technologie CMOS HV 0,8 µm de Teledyne DALSA dédiées à une intégration 3D avec leurs circuits d’étouffement actifs. Les résultats de caractérisation montrent que les SPAD atteignent une résolution temporelle de 27 ps largeur à mi hauteur (LMH), possèdent un taux de comptage en obscurité (DCR, ou Dark Count Rate) de 3 s[indice supérieur -1]µm[indice supérieur -2] et ont une probabilité de photodétection (PDP) de 49 %. De plus, une méthode d’isolation utilisant un puits p a été développée. Les SPAD conçus avec cette méthode ont un facteur de remplissage pouvant atteindre 54 % et une probabilité de diaphonie de 6,6 % à une tension excédentaire à la tension de claquage (V[indice inférieur E]) de 4 V.

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B??rub??, Beno??t-Louis. "Conception de matrices de diodes avalanche ?? photon unique sur circuits int??gr??s CMOS 3D." Thèse, Universit?? de Sherbrooke, 2014. http://savoirs.usherbrooke.ca/handle/11143/92.

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La photod??tection est un sujet de recherche tr??s actif encore de nos jours et l???industrie, particuli??rement de la physique des hautes ??nergies et de l???imagerie m??dicale, est en qu??te de d??tecteurs avec une plus grande sensibilit??, de meilleures r??solutions temporelles et une plus grande densit?? d???int??gration. Pour ces raisons, les photodiodes avalanche ?? photon unique (Single photon avalanche diode, ou SPAD) suscitent beaucoup d???int??r??t depuis quelques ann??es pour ses performances en temps et sa grande photosensibilit??. Les SPAD sont des photodiodes avalanche op??r??es au-dessus de la tension de claquage et un photoporteur atteignant la r??gion de multiplication peut ?? lui seul d??clencher une avalanche soutenue de porteurs et entra??ner le claquage de la jonction. Un circuit d??tecte le courant divergent et l?????touffe en abaissant la polarisation de la jonction sous la tension de claquage. Le circuit recharge ensuite la jonction en r??appliquant la tension initiale permettant la d??tection d???un nouveau photon. Dans le but d???augmenter le nombre de photons simultan??s d??tectables, les SPAD s???int??grent en matrice. Cependant, dans le cas o?? une matrice de SPAD et leurs circuits d?????touffement s???int??grent sur le m??me substrat, la surface photosensible devient limit??e par l???espace qu???occupent les circuits d?????touffement. Dans le but d???augmenter leur r??gion photosensible, les matrices de SPAD peuvent s???int??grer en trois dimensions (3D) avec leurs circuits d?????touffement. Ce projet porte sur le d??veloppement de matrices de SPAD en technologie CMOS HV 0,8 ??m de Teledyne DALSA d??di??es ?? une int??gration 3D avec leurs circuits d?????touffement actifs. Les r??sultats de caract??risation montrent que les SPAD atteignent une r??solution temporelle de 27 ps largeur ?? mi hauteur (LMH), poss??dent un taux de comptage en obscurit?? (DCR, ou Dark Count Rate) de 3 s[indice sup??rieur -1]??m[indice sup??rieur -2] et ont une probabilit?? de photod??tection (PDP) de 49 %. De plus, une m??thode d???isolation utilisant un puits p a ??t?? d??velopp??e. Les SPAD con??us avec cette m??thode ont un facteur de remplissage pouvant atteindre 54 % et une probabilit?? de diaphonie de 6,6 % ?? une tension exc??dentaire ?? la tension de claquage (V[indice inf??rieur E]) de 4 V.

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Helleboid, Rémi. "Advanced modeling and simulation of Single-Photon Avalanche Diodes." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPAST193.

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Cette thèse fait progresser la modélisation, la simulation et l'optimisation des diodes à avalanche à photon unique (Single-Photon Avalanche Diodes, ou SPAD), capables de détecter des photons individuels avec une grande sensibilité. Les SPAD sont essentiels dans des applications telles que les communications quantiques, l'imagerie et les mesures de temps de vol, où la détection précise de photons uniques est cruciale. Cependant, les SPAD fonctionnent par des processus complexes et stochastiques, comme la multiplication par avalanche, la gigue temporelle et l'extinction, rendant leur modélisation précise difficile. Cette thèse aborde ces complexités en développant des modèles de simulation avancés, en appliquant des techniques d'optimisation et en explorant des méthodes pour améliorer les performances des SPAD. La thèse commence par une revue de la technologie SPAD et de ses principes. Les SPAD détectent les photons en déclenchant un processus d'avalanche dans un champ électrique élevé, qui amplifie le signal du photon en une impulsion mesurable. Cette thèse étend le modèle de McIntyre, traditionnellement utilisé pour les dispositifs à avalanche, en trois dimensions, permettant des simulations plus précises des géométries complexes et des champs électriques des SPAD. Une contribution majeure est l'introduction de l'optimisation par essaim de particules (Particle Swarm Optimization, ou PSO) couplée à un solveur de Poisson non linéaire pour optimiser des paramètres de SPAD comme la tension de claquage, la largeur de la zone de déplétion et la gigue temporelle. La PSO explore efficacement l'espace de conception, équilibrant les exigences de performance et permettant la création de SPADs adaptés à diverses applications, de l'imagerie en basse lumière à la détection rapide de photons. Pour améliorer la précision des simulations de SPAD, la thèse développe une méthode Monte Carlo par advection-diffusion (ADMC), qui combine les processus d'advection et de diffusion pour modéliser de manière réaliste le transport des porteurs, notamment dans les zones de champ élevé où les avalanches se produisent. Ce modèle surmonte les limites des méthodes Monte Carlo traditionnelles, permettant une représentation précise de la gigue temporelle, de la probabilité de claquage et du taux de comptage de bruit.La thèse culmine avec le développement d'un modèle auto-cohérent Monte Carlo-Poisson pour les simulations transitoires de SPAD. En combinant ADMC avec un solveur de Poisson en 3D, ce modèle capture en temps réel des comportements critiques des SPAD, tels que l'initiation de l'avalanche, la réduction de champ et l'extinction. Cette boucle de rétroaction est essentielle pour comprendre les comportements transitoires des SPAD, car les porteurs influencent le champ électrique lorsqu'ils s'accumulent. Ce modèle est particulièrement utile pour étudier la nature stochastique de l'extinction, qui affecte la fiabilité et la temporalité des SPAD. En résumé, cette thèse apporte des contributions significatives à la modélisation, la simulation et l'optimisation des SPAD. En développant un modèle auto-cohérent Monte Carlo-Poisson et en intégrant des techniques avancées d'optimisation, ce travail fournit un cadre complet pour améliorer les performances des SPAD et soutenir les avancées futures dans des applications de haute précision
This thesis advances the modeling, simulation, and optimization of Single-Photon Avalanche Diodes (SPADs), which detect individual photons with high sensitivity. SPADs are essential for applications in quantum communications, imaging, and time-of-flight measurements, where precise single-photon detection is crucial. However, SPADs operate through complex, stochastic processes such as avalanche multiplication, timing jitter, and quenching, making accurate modeling a challenge. This thesis addresses these complexities by developing advanced simulation models, applying optimization techniques, and exploring methods to enhance SPAD performance. The thesis starts by reviewing SPAD technology and principles. SPADs detect photons by triggering an avalanche process in a high electric field, which amplifies the photon's signal into a measurable pulse. This thesis extends the McIntyre model, traditionally used for avalanche devices, to three dimensions, allowing for more accurate simulations of complex SPAD geometries and electric fields. A core contribution is introducing Particle Swarm Optimization (PSO) coupled with a nonlinear Poisson solver to optimize SPAD parameters like breakdown voltage, depletion width, and timing jitter. PSO navigates the design space effectively, balancing competing performance requirements and enabling customized SPADs for different applications, from low-light imaging to fast photon counting. To improve SPAD simulation accuracy, the thesis develops an Advection-Diffusion Monte Carlo (ADMC) method, which combines advection and diffusion processes for a realistic model of carrier transport, especially in high-field regions where avalanches occur. This model overcomes limitations of traditional Monte Carlo methods, achieving accurate representations of timing jitter, breakdown probability, and dark count rate. The thesis culminates in a self-consistent Monte Carlo-Poisson model for transient SPAD simulations. By combining ADMC with a 3D Poisson solver, this model captures critical SPAD behaviors like avalanche initiation, field depletion, and quenching in real time. This feedback loop is essential for understanding transient SPAD behaviors, as carriers impact the electric field as they accumulate. The model is especially useful for studying the stochastic nature of quenching, which influences SPAD reliability and timing. In summary, this thesis makes significant contributions to SPAD modeling, simulation, and optimization. By creating a self-consistent Monte Carlo-Poisson model and integrating advanced optimization techniques, this work provides a comprehensive framework for improving SPAD performance and supports further advances in high-precision applications

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Sicre, Mathieu. "Study of the noise aging mechanisms in single-photon avalanche photodiode for time-of-flight imaging." Electronic Thesis or Diss., Lyon, INSA, 2023. http://www.theses.fr/2023ISAL0104.

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Les diodes à avalanche à photon unique (SPAD) sont utilisées pour les capteurs à temps de vol afin de déterminer la distance d'une cible. Cependant, ils sont sujets à des déclenchements parasites par des porteurs de charge générés de manière parasitaire, quantifiés en tant que taux de comptage dans l’obscurité (DCR), ce qui peut compromettre la précision de la distance mesurée. Pour résoudre ce problème, une méthodologie de simulation a été mise en place pour évaluer le DCR. Cela est réalisé en simulant la probabilité de claquage d'avalanche, intégrée avec le taux de génération de porteurs de charge à partir de défauts. Cette méthodologie permet d'identifier les sources potentielles de DCR avant stress. Pour garantir l'intégrité des mesures de distance sur une longue période, il est nécessaire de prédire le niveau de DCR dans diverses conditions d'exploitation. La méthodologie de simulation susmentionnée est utilisée pour identifier les sources potentielles de DCR après stress. Pour un modèle cinétique précis de dégradation de type porteurs chauds (HCD), il est essentiel de considérer non seulement la distribution d'énergie des porteurs, mais également la distribution de l'énergie de dissociation de la liaison Si-H à l'interface Si/SiO2. La probabilité de dissociation d'ionisation d'impact est utilisée pour modéliser le processus de création de défauts, qui présente une dépendance temporelle sous-linéaire en raison de l'épuisement progressif des précurseurs de défauts. Une mesure précise de la distance nécessite de distinguer le signal du bruit ambiant et du plancher de DCR. L'impact de DCR peut être estimé en considérant la réflectance de la cible et les conditions d'éclairage ambiant. En résumé, ce travail utilise une méthodologie de caractérisation et de simulation approfondie pour prédire le DCR dans les dispositifs de type SPAD le long de sa durée de vie, permettant ainsi d'évaluer son impact sur les mesures de distance
Single-Photon Avalanche Diode (SPAD) are used for Time-of-Flight (ToF) sensors to determine distance from a target by measuring the travel time of an emitted pulsed signal. These photodetectors work by triggering an avalanche of charge carriers upon photon absorption, resulting in a substantial amplification which can be detected. However, they are subject to spurious triggering by parasitic generated charge carriers, quantified as Dark Count Rate (DCR), which can compromise the accuracy of the measured distance. Therefore, it is crucial to identify and eliminate the potential source of DCR. To tackle this issue, a simulation methodology has been implemented to assess the DCR. This is achieved by simulating the avalanche breakdown probability, integrated with the carrier generation rate from defects. The breakdown probability can be simulated either in a deterministically, based on electric-field streamlines, or stochastically, by means of drift-diffusion simulation of the random carrier path. This methodology allows for the identification of the potential sources of pre-stress DCR by comparing simulation results to experimental data over a wide range of voltage and temperature. To ensure the accuracy of distance range measurements over time, it is necessary to predict the DCR level under various operating conditions. The aforementioned simulation methodology is used to identify the potential sources of post-stress DCR by comparing simulation results to stress experiments that evaluate the principal stress factors, namely temperature, voltage and irradiance. Furthermore, a Monte-Carlo study has been conducted to examine the device-to-device variation along stress duration. For an accurate Hot-Carrier Degradation (HCD) kinetics model, it is essential to consider not only the carrier energy distribution function but also the distribution of Si−H bond dissociation energy distribution at the Si/SiO2 interface. The number of available hot carriers is estimated from the carrier current density according to the carrier energy distribution simulated by means of a full-band Monte-Carlo method. The impact-ionization dissociation probability is employed to model the defect creation process, which exhibits sub-linear time dependence due to the gradual exhaustion of defect precursors. Accurate distance ranging requires distinguishing the signal from ambient noise and the DCR floor, and ensuring the target’s accumulated photon signal dominates over other random noise sources. An analytical formula allows to estimate the maximum distance ranging using the maximum signal strength, ambient noise level, and confidence levels. The impact of DCR can be estimated by considering the target’s reflectance and the ambient light conditions. In a nutshell, this work makes use of a in-depth characterization and simulation methodology to predict DCR in SPAD devices along stress duration, thereby allowing the assessment of its impact on distance range measurements

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Panglosse, Aymeric. "Modélisation pour la simulation et la prédiction des performances des photodiodes à avalanche en mode Geiger pour Lidars spatiaux." Thesis, Toulouse, ISAE, 2019. http://www.theses.fr/2019ESAE0046.

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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

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Pellegrini, Sara. "InGaAs/InP single-photon avalanche diodes." Thesis, Heriot-Watt University, 2005. http://hdl.handle.net/10399/49.

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Rochas, Alexis. "Single photon avalanche diodes in CMOS technology /." [S.l.] : [s.n.], 2003. http://library.epfl.ch/theses/?nr=2814.

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Chitnis, Danial. "Single photon avalanche diodes for optical communications." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:5fd582dd-8167-4fe4-88f8-871ba905ade1.

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In order to improve the sensitivity of an optical receiver, the gain and the collection area of the photo-detectors within the receiver should be increased. Detectors with internal gain such as avalanche photodiodes (APD) are usually used to increase the sensitivity of the receiver. One problem with APDs is the sensitivity of their gain to their bias voltage, which makes them challenging to be fabricated in a standard CMOS process due to variations in their gain. However, when an APD is biased over its breakdown voltage, it is sensitive to a single photon, hence, referred to as a single photon avalanche diodes (SPAD). The SPADs are photon-counting detectors, which are less sensitive to their bias voltage, and can be integrated with rest of the electronic circuitry that form an optical receiver. An avalanche diode requires dedicated circuits to be operated in the SPAD mode. These circuits make the diode insensitive to an incident photon for a duration that is known as deadtime. Unfortunately, The collection area of the PD, APD, and SPADs are limited to their capacitance. Hence, a large photo-detector leads to a larger capacitance, which reduces the bandwidth of the receiver. In this thesis, a photon counting optical receiver based on an array of SPADs is proposed which increases the collection area with a low output capacitance. The avalanche diode and peripheral circuits which operate and readout-out the SPAD array are fabricated in the commercially available UMC 0.18 μm CMOS process. Initially, the avalanche diode is tested and characterised. A high performance circuit is then designed and tested which is able to achieve short deadtimes up to 4 ns. Once the photon counting operation of the SPAD is verified, a numerical model is developed to investigate the influence of several factors, including the deadtime, on the performance of the photon-counting detector in a communication link. Based on the simulation results, which show the advantages of an array over a single detector, a prototype detector array of 64 asynchronous SPADs is designed and tested. This array uses a high-speed readout mechanism which is inspired by the current steering digital-to-analogue converters. Bit error ratio tests (BERT) verify the photon counting capability of the proposed detector, and a bit error rate of 1E-3 has been achieved at data rate of 100 Mbps. In addition, the array of SPAD is compatible with a front-end of conventional optical receiver which uses a photodiode as a photo detector.

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Alsolami, Ibrahim. "Visible light communications with single-photon avalanche diodes." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:744eeb47-8bb6-4776-8b8f-f7b6374d89bd.

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This thesis explores the use of single-photon avalanche diodes (SPADs) for visible light communications (VLC). The high sensitivity of SPADs can potentially enhance the performance of VLC receivers. However, a SPAD-based system has challenges that need to be addressed before it can be considered as a viable option for VLC. The first challenge is the susceptibility of SPAD-based receivers to variations in ambient light. The high sensitivity of SPADs is advantageous for signal detection, but also makes SPADs vulnerable to variations in ambient light. In this thesis, the performance of a SPAD-based receiver is investigated under changing lighting conditions. Analytical expressions to quantify performance are derived, and an experiment is conducted to gain further understanding of system performance. It is shown that a SPAD-based receiver is highly sensitive to illumination changes when on-off keying (OOK) is employed, and that pulse-position modulation (PPM) is a preferred modulation scheme as it is more robust. The second challenge is broadcasting to SPAD-based receivers with different capabilities. A traditional broadcasting scheme is time-sharing, whereby a transmitter sends data to receivers in an alternating manner. Broadcasting to SPAD-based receivers is challenging as receivers may have diverse capabilities. In this thesis, a new multiresolution modulation scheme is proposed, which can potentially improve system performance over the traditional timesharing approach. The performance of the proposed scheme is analyzed, and a proof-of-concept experiment is performed to demonstrate its viability.

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Jouni, Ali. "Space radiation effects on CMOS single photon avalanche diodes (SPADs)." Electronic Thesis or Diss., Toulouse, ISAE, 2024. http://www.theses.fr/2024ESAE0012.

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Le sujet de cette thèse traite des effets des radiations spatiales sur des détecteurs CMOS à avalanches, et particulièrement sur les dispositifs SPADs (pour Single Photon Avalanche Diode en anglais, ou photodiode à avalanche à photon unique). Ces photodiodes présentent un gain interne presque infini et sont donc sensibles à des très faibles conditions de lumières. Ainsi, avec en plus une excellente résolution temporelle, ces capteurs peuvent être très intéressant pour des applications spatiales nécessitant des mesures de temps de vols, comme la topographie d’objets célestes ou les Rendez-vous spatiaux. Cependant, l’espace est un environnement hostile du fait des radiations provenant du Soleil, des particules piégées dans la magnétosphère terrestre ainsi qu’au-delà du système solaire. De ce fait, dans le cadre de ces travaux de thèse, un modèle est mis en place pour prédire la dégradation du courant d’obscurité des SPADs, le Dark Count Rate (DCR), après des irradiations aux protons. Expérimentalement, deux technologies de matrices de SPADs sont irradiées avec des protons, des rayons X et des rayons γ. De ce fait, les effets ionisants et non-ionisants sont investigués pour ces capteurs à avalanches, et des différences en comparaison avec les pixelsdes capteurs d’images standard sont soulignées. Ensuite, les caractéristiques des défauts induits par la création d’états d’interface entre les oxides et le silicium et les dommages de déplacement atomique dans le substrat sont examinées, avec notamment la présence de comportement RTS (Random Telegraph Signal). Enfin, l’identification de la nature de ces défauts est réalisée par l’intermédiaire de recuits isochrones après l’expositions des matrices de SPADs aux trois différentes radiations mentionnées au-dessus
The subject of this thesis deals with the effects of space radiation on CMOS avalanche detectors, particularly on Single Photon Avalanche Diodes (SPADs). These photodiodes exhibit nearly infinite internal gain and are therefore sensitive to very low light conditions. Thus, with excellent temporal resolution, these sensors can be very interesting for space applications requiring time-of-flight measurements, such as the topography of celestial objects or space Rendezvous. However, space is a hostile environment due to radiation from the Sun, particles trapped in the Earth’s magnetosphere, and beyond the solar system. Consequently, within the framework of this thesis work, a model is established to predict thedegradation of the dark current of SPADs, the Dark Count Rate (DCR), after proton irradiations. Experimentally, two SPAD array technologies are irradiated with protons, X-rays, and γ rays. Hence, ionizing and non-ionizing effects are investigated for these avalanche sensors, and differences compared to pixels of standard image sensors are highlighted. Subsequently, the characteristics of defects induced by the creation of interface traps between oxides and silicon and atomic displacement damage in the substrate are examined, including the presence of Random Telegraph Signal (RTS) behaviors. Finally, the nature of these defects is identified through isochronal annealing after irradiations of the SPAD arrays using the three different radiation types mentioned above

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Dean, Sam Patrick 1956. "The use and design of geiger mode avalanche diodes to count photons." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276761.

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Astronomers need single photon detectors to detect very faint light sources from deep space. An avalanche photodiode in the geiger mode is especially suited for the detection of single photons. Three by three arrays of avalanche photodiodes were fabricated. Breakdown voltages of 200V were measured. Large reverse currents prevented operating the array in the geiger mode. An improved design which minimizes the reverse current is needed. A commercial avalanche photodiode especially made for the geiger mode was tested and compared to a general purpose avalanche photodiode. Using the general purpose avalanche in the geiger mode was found to be unacceptable because when exposed to a weak light source, 90% of the output pulses were dark current pulses. A computer interface circuit was designed to read the time and location where photons were absorbed by the array. The circuit performed its function qualitatively, but it had a false triggering problem.

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Allred, Phil. "The development and optimization of potential germanium on silicon single photon avalanche diodes." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/80601/.

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The work presented in this thesis explores a potential single photon detection technology using Silicon and Germanium, and a possible direction for the future. Instead of the more commonly used III-V materials, the desirable characteristics of each of the Group IV materials is implemented in designing a separate absorption and multiplication region device. Key structural features of the device are investigated and optimised, so that single photon detection in the near infrared is made possible. Growth of these layers is performed using an RP-CVD system, the ultimate industry tool in this field of research. Doping profiles and smooth crystalline growth is implemented using a range of techniques, to produce suitable epitaxial structures which are ideal for further fabrication. Several techniques are used to ensure that the quality of these layers are fully optimised. This optimisation work has resulted in the first single photon detection at a wavelength of 1550 nm, and has also brought the Silicon and Germanium device onto a comparable level to their III-V counterparts at 1330 nm. The superior repetition rate of these Group IV devices also holds an advantage over those designed using InGaAs/InP. The boron doping of Silicon has also been investigated. It has been shown that fully crystalline Silicon boron layers can be produced with boron concentrations (4.5x1020 cm-3) that are higher than their solubility limit at 700oC. The reproducibility of these layers, along with quick turnaround, offers an excellent possibility for industrial use, with a significant advantage over other competing growth techniques. In relation to the work on the single photon detection devices, these B-doped layers offer an interesting etch resistant capability. Suspended structures (wires and membranes) have been produced and characterized using synchrotron measurements. Layers have shown small levels of strain, similar to structures made using Germanium, but overall exhibit a flat platform for further growth. This has led to the idea that suspending a single photon detector that incorporates a reflective mirror could enhance detection efficiency.

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Chaves, De Albuquerque Tulio. "Integration of Single Photon Avalanche Diodes in Fully Depleted Silicon-on-Insulator Technology." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI091.

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Ce travail a pour objectif la conception, la simulation, la modélisation et la caractérisation électrique de diodes à avalanche à photon unique (Single Photon Avalanche Diodes - SPAD) intégrées dans une technologie CMOS Fully Depleted Silicon on Insulator - FDSOI. Les SPAD sont des diodes (jonctions PN) polarisées en inverse au-delà de la tension de claquage, fonctionnant dans le mode Geiger. Grace à leur haute sensibilité et rapidité, les SPAD sont utiles pour plusieurs applications, telles que les mesures de temps de vol (Time of Flight - ToF), l’imagerie médicale (Fluorescence Lifetime Imaging Microscopy - FLIM), ainsi que la détection de particules chargées, dans le domaine de la physique de haute énergie. L’intégration de SPAD dans une technologie CMOS FDSOI permet d’obtenir une intégration 3D monolithique intrinsèque avec la diode sous l’oxyde enterré, et l’électronique associée dans le film silicium, en optimisant ainsi le facteur de remplissage. Afin d’analyser le comportement des SPAD FDSOI, plusieurs cellules ont été conçues, respectant les principales règles de dessin imposées par la fonderie, mais présentant des variantes structurelles telles que la zone d'intégration, la géométrie, la distance de garde et le circuit d’étouffement. Des simulations TCAD et des calculs analytiques ont été effectués afin d'estimer les principales figures du mérite de SPAD. Plusieurs modèles d'avalanche et de génération de porteurs ont été étudiés pour une meilleure adaptation du modèle simulé aux dispositifs fabriqués. Des caractérisations électriques ont été réalisées pour estimer des paramètres importants tels que la tension de claquage, le taux de comptage dans l'obscurité (DCR) et la réponse en l'électroluminescence. Bien que les résultats obtenus restent inférieurs par rapport à l'état de l’art, la faisabilité d’intégration de SPAD dans une technologie FDSOI a été démontrée comme preuve de concept, mais des améliorations sont nécessaires et certaines pistes sont proposées
This work aims at the design, simulation, modelling and electrical characterization of Single Photon Avalanche Diodes (SPAD) in an advanced Fully Depleted Silicon on Insulator (FDSOI) technology. SPADs are PN junctions reversed bias above breakdown voltage, operating in the so-called Geiger mode. Such an implementation should provide an intrinsic monolithic integration of those devices, along with their mandatory associated electronics, thanks to the buried oxide layer present in that technology, optimizing fill factor. Due to its high sensitivity, SPAD are useful for several applications, such as Time of Flight (ToF) and Fluorescence Lifetime Imaging Microscopy (FLIM) measurements, as well as the detection of charged particles, in high-energy physics domain. The designed cells follow the main design rules imposed by the foundry and present variations in aspect as integration zone, geometry, guard distance and quenching circuit. TCAD simulations were performed in order to estimate some of the SPAD main Figures of Merit. Several avalanche and carrier generation models were studied for better adapting the simulated model to the actual fabricated devices. Electrical characterizations were realized for estimating important parameters such as breakdown voltage, Dark Count Rate (DCR) and electroluminescence response. Although the obtained results are still poor when compared to State-of-the-Art, its feasibility was demonstrated and can be used as a proof of concept, at the same time that improvements are proposed

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Fancey, Stuart James. "Single-photon avalanche diodes for time-resolved photoluminescence measurements in the near infra-red." Thesis, Heriot-Watt University, 1996. http://hdl.handle.net/10399/1309.

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Devita, Marie. "Mesure et dangerosité des métaux nobles pour les photodétecteurs à avalanche à photon unique." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD029/document.

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Les métaux nobles (Au, Ag, Pt, Ir, Pd et Ru) sont utilisés en salle blanche pour la réalisation de dispositifs électroniques ou peuvent être apportés par les équipements de fabrication (composants d’alliage par exemple). Il a été montré qu’ils pouvaient impacter fortement les dispositifs. Il est alors nécessaire de procéder au contrôle des équipements pour diagnostiquer au plus tôt une contamination. Or, il n’existe pas de technique industrielle pour leur suivi et ce à des niveaux d’au moins 5.109 at.cm-2 - recommandation ITRS. Il se pose la question de la pertinence de ces recommandations en fonction des types de dispositifs (SPAD notamment). Dans un premier temps, les travaux ont consisté à développer une technique physico-chimique pour l’analyse des métaux nobles sur silicium par VPD-DC-ICPMS. Enfin, leur dangerosité vis-à-vis des équipements et des dispositifs a été évaluée d’après leur comportement en température et le DCR généré sur SPAD
Noble metals (Au, Ag, Pt, Ir, Pd and Ru) are used for the fabrication of microelectronics devices or can be brought by manufacturing tools (alloy components for example). It is well known that these impurities are detrimental to the efficiency of the devices. This implies a real and present need for control of their introduction in clean rooms to diagnose as soon as possible a contamination. Yet, there are no industrial technique for their follow-up at levels about 5.109 at.cm-2 - ITRS recommendations. The relevance of these recommendations according to the electronic device (SPAD in particular) could be questioned. At first, this study consisted in developing a physicochemical technique for the analysis of noble metals on Si wafers by VPD-DC-ICPMS. Then, their dangerousness towards tools and devices was established according to their behavior in temperature and the DCR generated on SPAD devices

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Finkelstein, Hod. "Shallow-trench-isolation bounded single-photon avalanche diodes in commercial deep submicron CMOS technologies." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3274523.

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Thesis (Ph. D.)--University of California, San Diego, 2007.
Title from first page of PDF file (viewed October 3, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 256-271).

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Zhang, Yun. "Fabrication and characterization of GaN visible-blind ultraviolet avalanche photodiodes." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29604.

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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.

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Webster, Eric Alexander Garner. "Single-Photon Avalanche Diode theory, simulation, and high performance CMOS integration." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/17987.

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This thesis explores Single-Photon Avalanche Diodes (SPADs), which are solid-state devices for photon timing and counting, and concentrates on SPADs integrated in nano-scale CMOS. The thesis focuses on: the search for new theory regarding Geiger-mode operation; proving the utility of calibrated Technology Computer- Aided Design (TCAD) tools for accurately simulating SPADs for the first time; the investigation of how manufacture influences device operation; and the integration of high performance SPADs into CMOS which rival discrete devices. The accepted theories of SPAD operation are revisited and it is discovered that previously neglected minority carriers have many significant roles such as determining: after-pulsing, Dark Count Rate (DCR), bipolar “SPAD latch-up,” nonequilibrium DCR, and “quenching”. The “quenching” process is revisited and it is concluded that it is the “probability time” of ≈100-200ps, and not the previously thought latching current that is important. SPADs are also found to have transient negative differential resistance. The new theories of SPADs are also supported by steady-state 1D, 2D and 3D TCAD simulations as well as novel transient simulations and videos. It is demonstrated as possible to simulate DCR, Photon Detection Efficiency (PDE), guard ring performance, breakdown voltage, breakdown voltage variation, “quenching,” and transient operation of SPADs with great accuracy. The manufacture of SPADs is studied focusing on the operation and optimisation of guard rings and it is found that ion implantation induced asymmetry from the tilt and rotation/twist is critical. Where symmetric, guard rings fail first along the <100> directions due to enhanced mobility. Process integration rules are outlined for obtaining high performance SPADs in CMOS while maintaining compatibility with transistors. The minimisation of tunnelling with lightly-doped junctions and the reduction of ion implantation induced defects by additional annealing are found essential for achieving low DCR. The thesis demonstrates that it is possible to realise high performance SPADs in CMOS through the innovation of a “Deep SPAD” which achieves record PDE of ≈72% at 560nm with >40% PDE from 410-760nm, combined with 18Hz DCR, <60ps FWHM timing resolution, and <4% after-pulsing which is demonstrated to have potential for significant further improvement. The findings suggest that CMOS SPAD-based micro-systems could outperform existing photon timing and counting solutions in the future.

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Rae, Bruce R. "Micro-systems for time-resolved fluorescence analysis using CMOS single-photon avalanche diodes and micro-LEDs." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4219.

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Fluorescence based analysis is a fundamental research technique used in the life sciences. However, conventional fluorescence intensity measurements are prone to misinterpretation due to illumination and fluorophore concentration non-uniformities. Thus, there is a growing interest in time-resolved fluorescence detection, whereby the characteristic fluorescence decay time-constant (or lifetime) in response to an impulse excitation source is measured. The sensitivity of a sample’s lifetime properties to the micro-environment provides an extremely powerful analysis tool. However, current fluorescence lifetime analysis equipment tends to be bulky, delicate and expensive, thereby restricting its use to research laboratories. Progress in miniaturisation of biological and chemical analysis instrumentation is creating low-cost, robust and portable diagnostic tools capable of high-throughput, with reduced reagent quantities and analysis times. Such devices will enable point-of-care or in-the-field diagnostics. It was the ultimate aim of this project to produce an integrated fluorescence lifetime analysis system capable of sub-nano second precision with an instrument measuring less than 1cm3, something hitherto impossible with existing approaches. To accomplish this, advances in the development of AlInGaN micro-LEDs and high sensitivity CMOS detectors have been exploited. CMOS allows electronic circuitry to be integrated alongside the photodetectors and LED drivers to produce a highly integrated system capable of processing detector data directly without the need for additional external hardware. In this work, a 16x4 array of single-photon avalanche diodes (SPADs) integrated in a 0.35μm high-voltage CMOS technology has been implemented which incorporates two 9-bit, in-pixel time-gated counter circuits, with a resolution of 400ps and on-chip timing generation, in order to directly process fluorescence decay data. The SPAD detector can accurately capture fluorescence lifetime data for samples with concentrations down to 10nM, demonstrated using colloidal quantum dot and conventional fluorophores. The lifetimes captured using the on-chip time gated counters are shown to be equivalent to those processed using commercially available external time-correlated single-photon counting (TCSPC) hardware. A compact excitation source, capable of producing sub-nano second optical pulses, was designed using AlInGaN micro-LEDs bump-bonded to a CMOS driver backplane. A series of driver array designs are presented which are electrically contacted to an equivalent array of micro-LEDs emitting at a wavelength of 370nm. The final micro-LED driver design is capable of producing optical pulses of 300ps in width (full width half maximum, FWHM) and a maximum DC optical output power of 550μW, this is, to the best of our knowledge, the shortest reported optical pulse from a CMOS driven micro-LED device. By integrating an array of CMOS SPAD detectors and an array of CMOS driven AlInGaN micro-LEDs, a complete micro-system for time-resolved fluorescence analysis has been realised. Two different system configurations are evaluated and the ability of both topologies to accurately capture lifetime data is demonstrated. By making use of standard CMOS foundry technologies, this work opens up the possibility of a low-cost, portable chemical/bio-diagnostic device. These first-generation prototypes described herein demonstrate the first time-resolved fluorescence lifetime analysis using an integrated micro-system approach. A number of possible design improvements have been identified which could significantly enhance future device performance resulting in increased detector and micro-LED array density, improved time-gate resolution, shorter excitation pulse widths with increased optical output power and improved excitation light filtering. The integration of sample handling elements has also been proposed, allowing the sample of interest to be accurately manipulated within the micro-environment during investigation.

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Richardson, Justin Andrew. "Time resolved single photon imaging in nanometer scale CMOS technology." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/7588.

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Time resolved imaging is concerned with the measurement of photon arrival time. It has a wealth of emerging applications including biomedical uses such as fluorescence lifetime microscopy and positron emission tomography, as well as laser ranging and imaging in three dimensions. The impact of time resolved imaging on human life is significant: it can be used to identify cancerous cells in-vivo, how well new drugs may perform, or to guide a robot around a factory or hospital. Two essential building blocks of a time resolved imaging system are a photon detector capable of sensing single photons, and fast time resolvers that can measure the time of flight of light to picosecond resolution. In order to address these emerging applications, miniaturised, single-chip, integrated arrays of photon detectors and time resolvers must be developed with state of the art performance and low cost. The goal of this research is therefore the design, layout and verification of arrays of low noise Single Photon Avalanche Diodes (SPADs) together with high resolution Time-Digital Converters (TDCs) using an advanced silicon fabrication process. The research reported in this Thesis was carried out as part of the E.U. funded Megaframe FP6 Project. A 32x32 pixel, one million frames per second, time correlated imaging device has been designed, simulated and fabricated using a 130nm CMOS Imaging process from ST Microelectronics. The imager array has been implemented together with required support cells in order to transmit data off chip at high speed as well as providing a means of device control, test and calibration. The fabricated imaging device successfully demonstrates the research objectives. The Thesis presents details of design, simulation and characterisation results of the elements of the Megaframe device which were the author’s own work. Highlights of the results include the smallest and lowest noise SPAD devices yet published for this class of fabrication process and an imaging array capable of recording single photon arrivals every microsecond, with a minimum time resolution of fifty picoseconds and single bit linearity.

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Meng, Xiao. "InGaAs/InAlAs single photon avalanche diodes at 1550 nm and X-ray detectors using III-V semiconductor materials." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/11405/.

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Pellion, Denis. "Modélisation, fabrication et évaluation des photodiodes à avalanche polarisées en mode Geiger pour la détection du photon unique dans les applications Astrophysiques." Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00358847.

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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.

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Repich, Marina. "Development of a simulation environment for the analysis and the optimal design of fluorescence detectors based on single photon avalanche diodes." Doctoral thesis, University of Trento, 2010. http://eprints-phd.biblio.unitn.it/327/1/PhD-Thesis-Repich.pdf.

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Time-resolved fluorescence measurements enable the study of structure of molecular systems and dynamical processes inside them. This is possible because of a very high sensitivity of fluorescence lifetime to the physical and chemical properties of micro-environment in which fluorophores are situated. However, proper detection of the fluorescence lifetime is a challenging task, due to the fact that the fluorescence decay time of commonly used fluorophores lies in a nanosecond range. This puts strict requirements on the parameters of the fluorescence detectors. The features of single-photon avalanche diodes (SPAD) make these optical detectors a good alternative to conventional photomultiplier tubes and micro-channel plates. CMOS technology allows cointegration of a SPAD and electronic circuits on the same substrate and provides advantages in time resolution and noise characteristics. Monolithic integration of signal processing circuits and detectors on the same chip allows using such detectors without additional external hardware. New SPAD sensors with improved characteristics are produced every year. However, the designers consider various performance metrics while the importance of each particular detector characteristic depends on its application. Therefore, the validation and optimization of SPAD characteristics should be performed in a close connection with the analysis of a specific system, wherein this detector will be used. This work was aimed at developing of a model able to describe a typical fluorescence experiment with SPAD-based detector. The model simulates all essential parts of the fluorescence experiment starting from the light emission, through photo-physical processes occurring inside a bio-sample, to a detector itself and read-out electronics. The ability of the developed model to simulate various light sources (laser and micro-LED), fluorescence measurement techniques (time-correlated single photon counting and time-gating) was verified. The simulated results were in good agreement with the experimental data and the model proved its flexibility. Furthermore, the model provided the explanation of the distortions in experimental fluorescent curves measured under a very high ambient light when pile-up effects appear. Finally, a set of virtual experiments were established to investigate the influence of noisy pixels in SPAD array on a lifetime estimation and to study the feasibility of time-filtering instead of conventional optical filtering. Simulation results are in good agreement with data available in literature.

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Benhammou, Younes. "Développement de SPADs (Single Photon Avalanche Diodes) à cavité de germanium sur silicium en intégration 3D avec une technologie silicium CMOS 40nm." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI123.

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Cette thèse porte sur une famille de photo-détecteurs appelés SPAD pour Single Photon Avalanche Diodes qui sont des jonctions PN polarisées en inverse au-delà de la tension de claquage. Les diodes SPADs sont reconnues pour présenter de très bonnes performances en détection de faibles flux lumineux avec une réponse extrême rapide. Afin d’améliorer l’efficacité de détection dans le proche infrarouge de diodes SPAD sur silicium, les objectifs de la thèse sont de concevoir, fabriquer et caractériser une nouvelle génération de photodiodes SPADs dans une technologie CMOS 40nm en intégrant une cavité de germanium. Les travaux menés comportent i) un volet conception en utilisant des outils de simulation TCAD pour proposer une architecture originale optimisée, ii) le développement du flot complet du procédé technologique avec la création de nouvelles briques telles que la gravure de la cavité et l’épitaxie de germanium dopé in-situ, 3) la caractérisation électro-optique des composants issus des premiers lots fabriqués. Les analyses et interprétations des résultats obtenus révèlent la difficulté technologique pour réaliser une hétérojonction silicium-germanium sans défauts et une couche germanium de qualité. Néanmoins, les mesures réalisées ont démontré la capacité de cette nouvelle famille de SPAD à cavité de germanium sur plateforme silicium pour détecter les flux jusqu’à 1300nm, démontrant un fort potentiel applicatif pour les applications d’aide à la navigation
This thesis deals with a family of photo-detectors called SPAD for Single Photon Avalanche Diodes which are a PN junctions reverse biased beyond the breakdown voltage. SPADs diodes are known to have very good performance in detecting low light fluxes with an extremely fast response. In order to improve the near infrared detection efficiency of SPAD diodes on silicon, the objectives of the thesis are to design, manufacture and characterize a new generation of SPAD photodiodes in 40nm CMOS technology by integrating a germanium cavity. The work carried out includes i) design and simulation using TCAD tools to propose an optimized original architecture, ii) development of the process flow in industrial imager technological with the creation of new bricks such as etch of the cavity and epitaxy of germanium in-situ doped 3) the electro-optical characterization of the manufactured devices. The results obtained reveal technological difficulty to produce a silicon-germanium heterojunction without defects. Nevertheless, the measurements carried out demonstrated the ability of this new family of germanium cavity SPADs on a silicon platform to detect wavelengths up to 1300nm, demonstrating a strong potential for time of light applications

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Corbeil, Therrien Audrey. "Conception et modélisation de détecteurs de radiation basés sur des matrices de photodiodes à avalanche monophotoniques pour la tomographie d'émission par positrons." Thèse, Université de Sherbrooke, 2018. http://hdl.handle.net/11143/11909.

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La tomographie d'émission par positrons (TEP) se distingue des autres modalités d'imagerie par sa capacité à localiser et quantifier la présence de molécules marquées, appelées radiotraceurs, au sein d'un organisme. Cette capacité à mesurer l'activité biologique des différents tissus d'un sujet apporte des informations uniques et essentielles à l'étude de tumeurs cancéreuses, au fonctionnement du cerveau et de ses maladies neurodégénératives et de la pharmacodynamique de nouveaux médicaments. Depuis les tout débuts de la TEP, les scientifiques rêvent de pouvoir utiliser l'information de temps de vol des photons pour améliorer la qualité de l'image TEP. L'arrivée des photodiodes avalanche monophotoniques (PAMP), rend maintenant ce rêve possible. Ces dispositifs détectent la faible émission de lumière des scintillateurs et présentent une réponse grandement amplifiée avec une faible incertitude temporelle. Mais le potentiel des PAMP n'est pas encore entièrement exploré. Plutôt que de faire la somme des courants d'une matrice de PAMP, il est possible d'utiliser leur nature intrinsèquement binaire afin de réaliser un photodétecteur numérique capable de déterminer avec précision le temps d'arrivée de chaque photon de scintillation. Toutefois, la conception de matrices de PAMP numériques en est encore à ses débuts, et les outils de conception se font rares. Ce projet de doctorat propose un simulateur facilitant la conception de matrices de PAMP, que celles-ci soient analogiques ou numériques. Avec cet outil, l'optimisation d'une matrice de PAMP numérique basée dans une technologie Teledyne DALSA HV CMOS \SI{0,8}{\micro\metre} est proposée. En plus de guider les choix de conception de l'équipe, cette optimisation permet de mieux comprendre quels paramètres influencent les performances du détecteur. De plus, puisque le photodétecteur n'est pas l'unique acteur des performances d'un détecteur TEP, une étude sur l'impact des scintillateurs est aussi présentée. Cette étude vérifie l'amélioration apportée par l'intégration de photons prompts dans des scintillateurs LYSO. Enfin, une approche novatrice pour discriminer l'énergie des évènements TEP basée sur l'information temporelle des photons de scintillation a été développée et vérifiée à l'aide du simulateur. Bien que ce simulateur et les études réalisées dans le cadre de cette thèse soient concentrés sur des détecteurs TEP, l'utilité des PAMP et du simulateur ne se limite pas à cette application. Les matrices de PAMP sont prisées pour le développement de détecteur en physique des particules, physique nucléaire, informatique quantique, LIDAR et bien d'autres.
Abstract : Positron emission tomography (PET) stands out among other imaging modalities by its ability to locate and quantify the presence of marked molecules, called radiotracers, within an organism. The capacity to measure biological activity of various organic tissues provides unique information, essential to the study of cancerous tumors, brain functions and the pharmacodynamics of new medications. Since the very beginings of PET, scientists dreamed of using the photon's time-of-flight information to improve PET images. With the recent progress of Single Photon Avalanche Diodes (SPAD), this dream is now possible. These photodetectors detect the scintillators' low light emission and offers a greatly amplified response with only a small time uncertainty. However the potential of SPAD has not yet been entirely explored. Instead of summing the currents of a SPAD array, it is possible to use their intrinsically binary operation to build a digital photodetector, able to establish with precision the time of arrival of each scintillation photon. With this information, the time-of-flight measurements will be much more precise. Yet the design of digital SPAD arrays is in its infancy and design tools for this purpose are rare. This project proposes a simulator to aid the design of SPAD arrays, both analog and digital. With this tool, we propose an optimised design for a digital SPAD array fabricated in Teledyne Dalsa HV CMOS \SI{0.8}{\micro\metre} technology. In addition to guiding the design choices of our team, this optimisation led to a better understanding which parameters influence the performance of a PET detector. In addition, since the photodetector is not the sole actor in the performance of a PET detector, a study on the effect of scintillators is also presented. This study evaluates the improvement brought by incorporating a prompt photon emission mechanism in LYSO crystals. Finally, we describe a novel approach to energy discrimination based on the timing information of scintillation photons was developped and tested using the simulator. While this simulator and the studies presented in this thesis focus on PET detectors, SPAD are not limited to this sole application. SPAD arrays are promising for a wide variety of fields, including particle physics, high energy physics, quantum computing, LIDAR and many more.

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Parent, Samuel. "Conception, caractérisation et optimisation de SPAD en technologie Dalsa HV CMOS 0.8 μm pour intégration dans un 3D-SiPM." Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8850.

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Résumé : Les photodiodes à avalanche monophotonique (SPAD) sont d'intérêts pour les applications requérant la détection de photons uniques avec une grande résolution temporelle, comme en physique des hautes énergies et en imagerie médicale. En fait, les matrices de SPAD, souvent appelés photomultiplicateurs sur silicium (SiPM), remplacent graduellement les tubes photomultiplicateurs (PMT) et les photodiodes à avalanche (APD). De plus, il y a une tendance à utiliser les matrices de SPAD en technologie CMOS afin d'obtenir des pixels intelligents optimisés pour la résolution temporelle. La fabrication de SPAD en technologie CMOS commerciale apporte plusieurs avantages par rapport aux procédés optoélectroniques comme le faible coût, la capacité de production, l'intégration d'électronique et la miniaturisation des systèmes. Cependant, le défaut principal du CMOS est le manque de flexibilité de conception au niveau de l'architecture du SPAD, causé par le caractère fixe et standardisé des étapes de fabrication en technologie CMOS. Un autre inconvénient des matrices de SPAD CMOS est la perte de surface photosensible amenée par la présence de circuits CMOS. Ce document présente la conception, la caractérisation et l'optimisation de SPAD fabriqués dans une technologie CMOS commerciale (Teledyne DALSA 0.8µm HV CMOS - TDSI CMOSP8G). Des modifications de procédé sur mesure ont été introduites en collaboration avec l'entreprise CMOS pour optimiser les SPAD tout en gardant la compatibilité CMOS. Les matrices de SPAD produites sont dédiées à être intégrées en 3D avec de l'électronique CMOS économique (TDSI) ou avec de l'électronique CMOS submicronique avancée, produisant ainsi un SiPM 3D numérique. Ce SiPM 3D innovateur vise à remplacer les PMT, les APD et les SiPM commerciaux dans les applications à haute résolution temporelle. L'objectif principal du groupe de recherche est de développer un SiPM 3D avec une résolution temporelle de 10 ps pour usage en physique des hautes énergies et en imagerie médicale. Ces applications demandent des procédés fiables avec une capacité de production certifiée, ce qui justifie la volonté de produire le SiPM 3D avec des technologies CMOS commerciales. Ce mémoire étudie la conception, la caractérisation et l'optimisation de SPAD fabriqués en technologie TDSI-CMOSP8G.
Abstract : Single Photon Avalanche Diodes (SPAD) generate much interest in applications which require single photon detection and excellent timing resolution, such as high energy physics and medical imaging. In fact, SPAD arrays such as Silicon PhotoMultipliers (SiPM) are gradually replacing PhotoMultiplier Tubes (PMT) and Avalanche PhotoDiodes (APD). There is now a trend moving towards SPAD arrays in CMOS technologies with smart pixels control for high timing demanding applications. Making SPAD in commercial CMOS technologies provides several advantages over optoelectronic processes such as lower costs, higher production capabilities, easier electronics integration and system miniaturization. However, the major drawback is the lack of flexibility when designing the SPAD architecture because all fabrication steps are fixed by the CMOS technology used. Another drawback of CMOS SPAD arrays is the loss of photosensitive areas caused by the CMOS circuits integration. This document presents SPAD design, characterization and optimization made in a commercial CMOS technology (Teledyne DALSA 0.8 µm HV CMOS - TDSI CMOSP8G). Custom process variations have been performed in partnership with the CMOS foundry to optimize the SPAD while keeping the CMOS line compatibility. The realized SPAD and SPAD arrays are dedicated to 3D integration with either low-cost TDSI CMOS electronics or advanced deep sub-micron CMOS electronics to perform a 3D digital SiPM (3D-SiPM). The novel 3D-SiPM is intended to replace PMT, APD and commercially available SiPM in timing demanding applications. The group main objective is to develop a 10 ps timing resolution 3D-SiPM for use in high energy physics and medical imaging applications. Those applications require reliable technologies with a certified production capability, which justifies the actual effort to use commercial CMOS line to develop our 3D-SiPM. This dissertation focuses on SPAD design, characterization and optimization made in the TDSI-CMOSP8G technology.

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Liu, Mingguo. "Infrared single photon avalanche diodes /." 2008. http://wwwlib.umi.com/dissertations/fullcit/3302223.

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Huang, Yi-Hsiang, and 黃翊翔. "Size Effect and Crosstalk in Single Photon Avalanche Diodes." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/s5eawg.

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碩士
國立交通大學
電子研究所
105
To improve the spatial resolution, the scale-down detector structure design becomes the recent research trend. Our group has developed a small size single-photon avalanche diodes (SPAD) with 8 μm diameter active region. Though it owns extremely low dark counts, its sensitivity is much lower. In this work, we design SPADs in standard 0.18 μm high-voltage CMOS technology provided by TSMC. By measuring the SPADs with various sizes, we analyze and investigate the size effect. With TCAD simulation, we observe that the high impact ionization area and its proportion to active region become smaller when SPADs scale down. We infer that decreasing impact ionization area proportion to active region may be the main reason to the lower sensitivity of small-size SPADs. With Size effect research, we can provide the information which is beneficial to SPAD array design. Besides, we provide two 2x2 SPAD array structure design: the one is the SPAD array with electrode-ring sharing, the other is cathode-well sharing SPAD array. Comparing to the conventional SPAD array, our work provides high filling- factor(FF) advantage, which FF is up to 34 %. Though our device design has higher DCR, it still owns the low dark counts and high detection efficiency. Since the SPAD array intensity increases by reducing the space between devices, optical crosstalk problem becomes the main issue. We attempt to research device crosstalk with the 2x8 SPAD array provided by ITRI. Through the measurement, we observe that the crosstalk decay follows the inverse ratio to the distance square. We infer direct optical path dominates optical crosstalk, which benefits us to design the minimum spacing between SPADs.

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Fiore, Daniela, Salvatore Critelli, Calogero Pace, Felice Crupi, Capua Francesco Di, and Elio Angelo Tomarchio. "Random telegraph signal in CMOS single photon avalanche diodes." Thesis, 2019. http://hdl.handle.net/10955/1788.

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Ph.D. Course Science and Engineering of the Environment, the Structures and the Energy. Ciclo XXI
This dissertation is focused on single photon devices that have triggered a real revolution in the world of imaging, the Single Photon Avalanche Diodes (SPADs). These devices acquired immediately a great interest in the field of single photon imaging, since they showed great performances in several fields, such as quantum mechanics, optical fibres, fluorescent decays and luminescence in physics, chemistry, biology, medical imaging, etc. These applications require single photon detectors able to assure high performances in photon counting, such as high photon detection efficiency, high speed and extremely low noise detection. The interest on SPAD became wider as they have been implemented in Complementary Metal-Oxide Semiconductor (CMOS) technology, reaching the integration of quenching and post-processing circuits on the pixel itself. The high timing and spatial resolution, the low power performance, the easy integration of circuits made CMOS SPADs the best choice in the field of single photon detectors. The ability to detect individual photons with very high timing resolution, at the order of few tens of picoseconds, and with an internal gain of 106 allowed to reduce the complexity in amplification circuit. However, SPAD performance is also influenced by Dark Count Rate (DCR), i.e. no-photon induced count rate, and by Random Telegraph Signal (RTS) occurrence, i.e. DCR discrete fluctuations. DCRs are mainly due to defects introduced in the semiconductor lattice and in the oxide during the fabrication process. In addition, radiation environment can induce new defects in the silicon structure, knows as radiation-induced defects. These defects or cluster of defects create new energy levels in the bandgap and cause the generation of carriers in depletion regions through thermal processes (Shockley Read-Hall, SRH, processes) and tunneling processes. This results in the increase of the mean dark current and in RTS. An increased occurrence of RTS effects degrades the performances of the devices, since the randomisation of this signal makes impossible to calibrate correctly the device. Therefore, it is important to investigate RTS behaviour and recognize the defects involved in this mechanism. The identification of defects responsible for RTS and the understanding of its evolution could be very useful to limit the effects on the devices operating in radiation environment. The thesis is structured in four chapters. The first chapter introduces the semiconductor-based photodetectors, the evolution of these devices until to CMOS Single-Photon Counting Detectors (SPADs). SPADs are described in detail, by explaining the working principle and the associated electronic circuits. SPAD performances are also discussed, taking into consideration the crosstalk and afterpulse. The second chapter explains the mechanisms responsible for DCR increase and RTS occurrence, focusing on generated electron-hole pairs due to thermal trap-assisted transition or to trap-assisted tunnelling (TAT) and band-to-band tunnelling (BTBT) at high electric field. RTS phenomenon is described and several theoretical models to explain its origin are presented in this chapter. The third chapter describes SPADs device investigated in the experimental analysis, focusing on two different layouts implemented in the test-chip: P+/Nwell and Pwell/Niso layout. The experimental setup and SPAD characterization before irradiation is reported. The fourth chapter describes the proton irradiation test and presents the experimental RTS data and the evolution in frequency and time domain. The chapter reports also the experimental results obtained by RTS investigation on two different SPAD layouts. The results allowed to hypothesize an explanation involved in RTS phenomenon.
Università della Calabria

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Hsiao, Yu-Jung, and 蕭有容. "Image Array of Single Photon Avalanche Diodes with Parallel Output." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/76063886838182084149.

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碩士
國立交通大學
電子工程學系電子研究所
104
In this work, we realize a 12X12 pixels parallel output image array with a single photon avalanche diodes (SPADs) by using TSMC 0.18μm technology and by applying the passive-quenching active-reset circuit. We also build a read out interface for the SPAD array. In the system, FPGA and RS232 are used for signal counting and data transmission, and Labview software is for measured image display. The SPADs array has a good device uniformity with the mean dark count rate of 8082.87 Hz and with the mean photon detection efficiency of 2.97 %. The size of fabricated image array is 1.2X1.2 mm2, and its fill factor is 1.61%. The imaging function is demonstrated by taking a picture of a ready-made 0.36 inch red light seven segment.

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Chang, Shih-Cheng, and 張世承. "Design and Characteristics of InGaAs/InAlAs Single-photon Avalanche Diodes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/9zsz88.

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碩士
國立中央大學
電機工程學系
107
Single-photon Avalanche Diode (SPAD) is used to detect low power light via absorbing one photon and generating carriers to induce impact ionization process. SPAD attracts great interest in the field of near-infrared detection such as light detection and ranging (LiDAR), 3D imaging, fiber-optic communication, etc. In0.47Ga0.53As/In0.48Al0.52As SPAD, consisting of InGaAs absorption layer for the detection of near infrared light and InAlAs multiplication layer for achieving impact ionization process, have several advantages in comparison with the SPAD using a InP multiplication layer. The breakdown voltage of SPAD with InAlAs multiplication layer is more stable to the temperature than that of SPAD with InP multiplication layer. InAlAs also has higher avalanche breakdown probability than InP, hence higher photon detection efficiency is expected. Therefore, InAlAs becomes an alternative candidate for next generation of InGaAs SPAD. In this work, we design and fabricate top-illuminated and mesa type SACM avalanche photodiodes. With the aid of technology computer-aided design (TCAD) methods, we optimize the doping concentration of charge layers for gaining high enough electric field in the multiplication layer and low enough electric field in the absorption layer. We apply sulfur treatment on the exposed sidewall by using (NH4)2S before depositing passivation layer to reduce surface leakage current. With appropriate thickness of passivation and bonding pad, we have successfully carried out SPAD devices. The basic current-voltage characteristics of SPAD have been measured and analyzed. The breakdown voltage is around 47 V at room temperature and the temperature coefficient of breakdown voltage is 52 mV/K below 200K and 16 mV/K above 200K, 60 and 21 mV/K for another one. We analyzed the origin of dark current via different activation energy. For reducing the afterpulsing effect, we use gated mode operation. The avalanche signal is acquired under dark condition. Then the temperature dependences of dark count rate and photon count rate are measured for temperatures down to 77K. Finally, we discuss the main factors affecting the dark count rate and the photon detection efficiency of our devices.

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Chien, Sheng-Yu, and 簡盛宥. "Dark and Illumination Characteristics of InGaAs/InP Single Photon Avalanche Diodes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bpa2qs.

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碩士
國立中央大學
電機工程學系
107
InGaAs/InP single photon avalanche diodes are of great potential in the application of near-infrared optical fiber communication. However, comparing to Si single photon avalanche diodes, InGaAs/InP single photon avalanche diodes have higher dark count due to its material and structural characteristics. In this thesis, we characterize the dark count performance at different temperature ranges by operating the device under gated mode with frequency of 10 kHz and voltage pulse width of 20 ns. The device is cooled down to 77 K by using liquid nitrogen. From the experiments, different mechanisms are dominant over different temperature ranges. In high temperature region (200 K-300 K), the dark counts originate from the thermal generation. For the low temperature region (77 K-125 K), afterpulsing dominates. While in the intermediate temperature region (125 K-200 K), the dark count rates should be restricted to the tunneling carriers, however, a non-monotonic behavior in the dark count performance is observed, that is, a local maximum of dark count rates occurs at around 150 K. In order to study this phenomenon, we vary the internal electric field and found that the local maximum shifts to lower temperature, showing that the local maximum is sensitive to the internal electric field and hence is attributed to the charge persistence effect. To further evidence this argument, we illuminate the device with a time-varying incoming pulse laser. It is found that the charge persistence effect gets most serious at 150 K, where the local maximum of dark count rate occurs. At 200 K, where the thermal carriers are greatly suppressed, the device is almost free from the charge persistence effect. The investigation reflects that the charge persistence effect is involved in the intermediate temperature rage and it is iii caused not only by the photo-generated carriers but also by the thermal-generated carriers. We also attempt to see the impact of charge persistence effect on the photon detection efficiency. Our results reveal that the photon detection efficiency could be overestimated due to the existence of charge persistence effect.

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Lu, Ping-Keng, and 呂秉耕. "Temporal Characteristics of Photo-Counts and Dark Counts in Single Photon Avalanche Diodes." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/85944239133439573927.

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碩士
國立交通大學
電子工程學系電子研究所
102
In this work, the afterpulsing and timing jitter of several single-photon avalanche diodes (SPADs) of various structures and processes (TSMC 0.25μm High Voltage and 0.18μm) are measured. These two measurements can reveal the temporal characteristics of dark counts and photo-counts, respectively. They also provide information about the physical behavior of carriers in the devices. Regarding the measurement of afterpulsing, we take an approach different from the conventional one, with the intent to obtain the same outcome with a simpler experimental setup, which we call “timed pulse measurement”. In this method, quenching circuits are not required, and devices can be measured in several modes, from which the most suitable mode of measurement should be chosen considering the performance of the device of interest. According to the results, we compare the pros and cons of the modes and also evaluate the afterpulsing effects in each device. On the other hand, using a Ti:Sapphire femtosecond laser and a TCSPC module, we measure the timing jitter of the devices at 4ps resolution. In addition to observing the correlation of jitter value and the excess bias, we also examine the dependence on the position of the laser spot and on the device diameter, confirming some of the physical origins of timing jitter. The experimental data of both measurements can serve as a good reference for future modification on the device structures. Last of all, a group of devices with multiple cathodes are designed for further study of the temporal characteristics of breakdown propagation. Apart from enabling the study of breakdown propagation, these devices have great potential to be developed into position-sensitive detectors, opening a new direction for future research.

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