Analysis of total dose-induced dark current in CMOS image sensors from interface state and trapped charge density measurements

The origin of total ionizing dose induced dark current in CMOS image sensors is investigated by comparing dark current measurements to interface state density and trapped charge density measurements. Two types of photodiode and several thick-oxide-FETs were manufactured using a 0.18-µm CMOS image sensor process and exposed to 10-keV X-ray from 3 krad to 1 Mrad. It is shown that the radiation induced trapped charge extends the space charge region at the oxide interface, leading to an enhancement of interface state SRH generation current. Isochronal annealing tests show that STI interface states anneal out at temperature lower than 100°C whereas about a third of the trapped charge remains after 30 min at 300°C

Origin of Second Harmonic Generation from individual Silicon Nanowires

We investigate Second Harmonic Generation from individual silicon nanowires and study the influence of resonant optical modes on the far-field nonlinear emission. We find that the polarization of the Second Harmonic has a size-dependent behavior and explain this phenomenon by a combination of different surface and bulk nonlinear susceptibility contributions. We show that the Second Harmonic Generation has an entirely different origin, depending on whether the incident illumination is polarized parallel or perpendicularly to the nanowire axis. The results open perspectives for further geometry-based studies on the origin of Second Harmonic Generation in nanostructures of high-index centrosymmetric semiconductors.Comment: 7 Pages, 4 Figures + 3 Pages, 6 Figures in Appendi

Displacement Damage Effects in Pinned Photodiode CMOS Image Sensors

This paper investigates the effects of displacement damage in Pinned Photodiode (PPD) CMOS Image Sensors (CIS) using proton and neutron irradiations. The DDD ranges from 12 TeV/g to ${1.2 times 10^{6}}$ TeV/g. Particle fluence up to $5 times 10^{14}$ n.cm $^{-2}$ is investigated to observe electro-optic degradation in harsh environments. The dark current is also investigated and it would appear that it is possible to use the dark current spectroscopy in PPD CIS. The dark current random telegraph signal is also observed and characterized using the maximum transition amplitude

Radiation Effects in CMOS Isolation Oxides: Differences and Similarities With Thermal Oxides

Radiation effects in thick isolation oxides of modern CMOS technologies are investigated using dedicated test structures designed using two commercial foundries. Shallow Trench Isolation and Pre-Metal Dielectric are studied using electrical measurements performed after X-ray irradiations and isochronal annealing cycles. This paper shows that trapping properties of such isolation oxides can strongly differ from those of traditional thermal oxides usually used to process the gate oxide of Metal Oxide Semiconductor Field Effect Transistors. Buildup and annealing of both radiation-induced oxide-trap charge and radiation-induced interface traps are discussed as a function of the oxide type, foundry and bias condition during irradiation. Radiation-induced interface traps in such isolation oxides are shown to anneal below 100°C contrary to what is usually observed in thermal oxides. Implications for design hardening and radiation tests of CMOS Integrated Circuits are discussed

Adolescent hockey players’ predispositions to adopt sport and exercise behaviours: an ecological perspective

Organized sport yields many cognitive, social and physical benefits and is one of the most popular types of physical activity for children and adolescents. Despite the benefits of sports participation, a substantial proportion of adolescents fail to meet Canadian guidelines regarding physical activity. In this regard, it is relevant to understand the mechanisms underlying the adoption of various active behaviours. This study aims to identify the predisposing, enabling and reinforcing factors that potentially influence 4 categories of active behaviours using the Youth Physical Activity Promotion model (YPAP). Data was drawn from 416 male adolescent hockey players (Mage = 15.4; SD = 2) who completed a pre-validated questionnaire. Structural equation modeling and interaction analyses were performed to explain the contribution of each determinant. Findings reveal that there are different behavioural patterns based on the type of activity. The interaction between attitudes and environmental factors was a key predictor for each type of behaviour. Perceived competence was associated with more recreational activities, whereas the support of parents and coaches determined involvement in ice hockey. This study refined our understanding of physical activity participation among adolescents already involved in organized sports and emphasized the importance of considering multiple factors surrounding their environment. Several practical recommendations are made to improve young athletes’ predisposition to practice physical activity in an organized sports setting. © 2020 Huard Pelletier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Evolutions technologiques des rotors Eurocopter

Cette présentation a pour but de retracer l’évolution des technologies sur l’élément qui fait la particularité des hélicoptères: le rotor. Après avoir clairement explicité les enjeux à relever, nous détaillerons les échecs et les succès ayant conduit aux toutes dernières générations de rotors d’hélicoptères

Géométrie algébrique : théorèmes d'annulation sur les variétés toriques

Ce mémoire se veut une bonne introduction au sujet des variétés toriques ainsi qu’à la théorie des faisceaux. On exposera des résultats déjà présents dans la littérature, mais dont les preuves sont partielles, découpées dans plusieurs sources ou simplement trop complexes pour un lecteur débutant. On synthétisera et détaillera ces résultats en limitant (dans la mesure du possible) les connaissances requises à leur compréhension. On terminera ce mémoire par la démonstration de théorèmes d’annulation, permettant entre autres d’aborder la preuve (pour les variétés toriques) du théorème de Grauert-Riemenschneider. Prérequis : des connaissances de base sur les variétés algébriques ou sur l’homologie pourraient aider à mieux appréhender les concepts discutés dans ce mémoire, et certains exemples font référence aux surfaces de Riemann ou aux CW-complexes. Toutefois, aucune connaissance de niveau gradué n’est nécessaire.This master’s thesis is meant to be a good introduction to toric varieties and sheaves theory. We will show some results already present in the literature whose proofs are either incomplete, divided in multiple sources or too complex for a novice. We will synthesize and detail these results while avoiding (as much as possible) required knowledge of the subject. We will finish this thesis with a proof of some vanishing theorems, required to tackle the Grauert-Riemenschneider theorem’s proof (in the toric case). Prerequisite : some basic knowledge of algebraic varieties or homology would help understand some of the concepts we discuss and a few examples we give refer to Riemann surfaces or CW complexes. But no knowledge past undergraduate-level is required

Dossier n° 13 – Auto support en santé mentale en France

Cet article a pour objectif de situer le contexte historique et politique d’émergence d’un nouveau type d’organisation associative dans le champ de la santé mentale en France : les groupes d’entre aide mutuelle (GEM). Il s’agit d’avoir une approche descriptive du phénomène en s’interrogeant particulièrement sur l’entraide. Deux analyses seront proposées, l’une portant sur la dimension relationnelle de l’entraide, l’autre portant sur les effets bénéfiques de l’entraide. Les GEM sont apparus so..

Displacement damage effects due to neutron and proton irradiations on CMOS image sensors manufactured in deep submicron technology

Displacement damage effects due to proton and neutron irradiations of CMOS image sensors dedicated to imaging are presented through the analysis of the dark current behavior in pixel arrays and isolated photodiodes. The mean dark current increase and the dark current nonuniformity are investigated. Dark current histogram observations are compared to damage energy distributions based on GEANT 4 calculations. We also discuss, through annealing analysis, which defects could be responsible for the dark current in CMOS image sensors

Sublogarithmic uniform Boolean proof nets

Using a proofs-as-programs correspondence, Terui was able to compare two models of parallel computation: Boolean circuits and proof nets for multiplicative linear logic. Mogbil et. al. gave a logspace translation allowing us to compare their computational power as uniform complexity classes. This paper presents a novel translation in AC0 and focuses on a simpler restricted notion of uniform Boolean proof nets. We can then encode constant-depth circuits and compare complexity classes below logspace, which were out of reach with the previous translations.Comment: In Proceedings DICE 2011, arXiv:1201.034