Formation par projet et opportunité d'accès à distance à des ressources pédagogiques

National audienceLorsque l'apprentissage par projet couvre plusieurs thématiques, il apparaît que les étudiants sont d'autant plus sensibles à la qualité des ressources mises à disposition et à leur disponibilité. L'évaluation des étudiants est contrastée entre leur plébiscite du contenu de la formation et leur critique des ressources. L'accès à distance à de telles ressources répond à une partie de la problématique. La communication décrit une première expérience de formation par projet qui débouche sur une mise à disposition à distance d'un lot de ressources, assistée d'une pédagogie adaptée. Fort de cette expérience, une seconde proposition est présentée dans un contexte différent mais où des contraintes similaires persistent sur les ressources. La discussion fera l'objet d'un poster avec démonstration sur machine (PR). Il est évident que les propositions mises en oeuvre sont maintenant connues, mais peu usitées en fait, et elles sont applicables à d'autres contextes. Si l'opportunité d'accessibilité à distance de ressources est une réponse à une partie importante des faiblesses des retours d'expérience décrits ici, il n'est pas envisagé de formation à distance, problématique très différente

Optimisation de la terminaison d'une diode Schottky diamant haute tension

National audienceUne nouvelle architecture de terminaison est proposée pour les diodes Schottky diamant. En utilisant des simulations par éléments finis avec les outils Sentaurus TCAD (Technology Computer-Aided Design), nous avons étudié l'impact de simples modifications de l'architecture des plaques de champ sur la tension de claquage. La tenue en tension augmente, mais ces modifications ne permettent pas de réduire la valeur du champ électrique au bord de la plaque de champ dans le diélectrique. Plusieurs topologies avec des formes originales ont été proposées pour résoudre ce problème. Les simulations paramétriques ont été utilisées pour optimiser les paramètres technologiques de ces structures de terminaison en vue de réduire la valeur crête du champ électrique en bord de terminaison, tout en maintenant la tension de claquage élevée. La solution retenue a permis de réduire le champ électrique maximal de 57 à 13 MV/cm

High voltage (6kV) diamond TMBS diode design

International audienc

High voltage (6kV) diamond TMBS diode design

International audienc

A Review on Selected Patents about Trends Regarding Silicon Monolithic Power AC Switches

International audienceThis article deals with the evolution regarding silicon monolithic power AC switches design through reviewing selected patents. Key criteria that are considered in this review are device structure topologies, performances related to application areas and manufacturability. Three main categories of monolithic AC switches are presented and selected patents of each of these categories are described and discussed. Possible future developments and trends are also explored

3D TCAD Simulations for More Efficient SiC Power Devices Design

International audienceSiC devices become more and more prominent in the power semiconductor industry. Thanks to a technology that seems to be mature enough, SiC devices become more and more sophisticated. Therefore, they can be serious competitors to existing silicon devices in not so distant future at least for high temperature and high power applications. In addition to undoubtedly better electrical and thermal properties, SiC devices still require attention regarding their design. Indeed, the material is still more expensive than silicon and some limitations such as the inability to create deep p-n junctions prevent from re-using existing silicon design. Therefore, SiC devices should be designed so that the best trade-off between active area and breakdown voltage is achieved. In such a context, 3D TCAD can be become an interesting approach mostly thanks to modern computer farms

Simulation-Based Study About the Lifetime and Incident Light Properties Dependence of the Optically Triggered 4H-SiC Thyristors Operation

International audienceWe investigated a methodology to design light-triggered thyristors thanks to TCAD. The simulation model accuracy, especially the holding current and the minimum incident light intensity to turn-ON, were compared with experimental results. The influence of SiC epitaxial layer lifetime and the incident light properties (wavelength and intensity) on the optically triggered 4H-SiC thyristor characteristics have been studied by simulation. We considered the wavelength dependence of quantum efficiency, penetration depth, and photon energy. The holding current and turn-ON time depends on the lifetime. The minimum intensity to turn-ON the device significantly depends on the wavelength. This intensity becomes less than 0.003 times when the wavelength changed from 380 to 325 nm. In addition, the breakover voltage is affected by the constant incident light even if the intensity is tiny

Experimental and simulation results of optical beam induced current technique applied to wide bandgap semiconductors

International audiencePower electronic devices based on wide bandgap (WBG) semiconductors such as silicon carbide (SiC), gallium nitride (GaN) and diamond (C) offer better performances when compared to those based on silicon (Si). However, the peripheral protection of these devices must be carefully designed to sustain high voltage bias. This paper shows how the OBIC (Optical Beam Induced Current) technique applied to WBG semiconductor devices could be useful to study the efficiency of different protection techniques. Firstly, a theoretical approach is given to present the this electro-optical characterization method. Then, it is performed on high voltage power devices in a vacuum chamber allowing to study the spatial distribution of the electric field in the semiconductor. In addition, comparisons with Finite Elements Methods using TCAD tools are performed showing the local high electric field strength. Results are mainly focused on SiC devices for the sake of availability. This paper shows additional results and measurements on GaN and diamond Schottky diodes also. Finally, extraction of OBIC signals allows to know some physical features like ionization coefficients, minority carrier lifetime and local defects in semiconductors as shown in the last section

Simulation, characterization and implementation of a new SCR-based device with a turn-off capability for EOS-immune ESD power supply clamps in advanced CMOS technology nodes

International audienceA new SCR-based device for ESD protection is presented through TCAD simulation and experimental results on a standalone configuration and for a power supply ESD clamp strategy. The new device can turn-off even if the voltage power supply is applied at its Anode. We use 3D TCAD simulation for understanding its turn-on and turn-off behavior. At the same time, the flexibility of the EOS test bench allows for standalone and power supply clamp characterizations at chip level at ambient and high temperature