Foreword

This work reports on the performances of ohmic contacts fabricated on highly p-type doped 4H-SiC epitaxial layer selectively grown by vapor-liquid-solid transport. Due to the very high doping level obtained, the contacts have an ohmic behavior even without any annealing process. Upon variation of annealing temperatures, it was shown that both 500 and 800 °C annealing temperature lead to a minimum value of the Specific Contact Resistance (SCR) down to 1.3×10−6 Ω⋅cm2. However, a large variation of the minimum SCR values has been observed (up to 4×10−4 Ω⋅cm2). Possible sources of this fluctuation have been also discussed in this paper

Procedimiento para la purificación de Triglicéridos que contienen ácido Estearidónico en posición SN-2

Número de publicación: ES2363518 A1 (08.08.2011)También publicado como: ES2363518 A8 (10.04.2012), ES2363518 B1 (13.06.2012)Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P201000070(23.01.2010)Procedimiento para la purificación de triglicéridos que contiene ácido estearidónico en posición sn-2. La invención se refiere a un procedimiento para la purificación de TGs ricos en SDA en posición sn-2 mediante cromatografía en columna gravimétrica, a un extracto de TGs ricos en SDA en posición sn-2 obtenido mediante dicho procedimiento y su uso en la industria.Univerisda de Almerí

Comparison of electrical properties of ohmic contact realized on p-type 4H-SiC

International audienceN+ 4H-SiC commercial substrates with n-type epilayers have been used to realize bipolar diodes and TLM structures. The p-type emitter of diodes was realized by Al implantations followed by a post-implantation annealing with or without a graphite capping layer. Ohmic contacts were formed by depositing Ti/Ni on the backside and Ni/Al on the topside of the wafer. It appears that capping the sample during the annealing reduces considerably the surface roughness and the specific contact resistance. Sheet resistance and specific contact resistance as low as 2kΩ/□ and respectively 1.75×10-4 Ωcm² at 300 K have been obtained. I-V measurements as a function of temperature have been performed from ~100 to ~500 K. The variations of the series resistance vs. temperature can be explained by the freeze-out of carriers and by the variation of carrier mobility

Simulation and design of junction termination structures for diamond Schottky diodes

International audienceIn this paper, the first step of the design of a junction termination structure usable on diamond Schottky diodes is introduced. Through the collaboration of AMPERE and LAAS laboratories, a study of junction termination structures using field plates and semiresistive materials was carried out. Several results from simulations of P type Schottky diodes protected by MESA coated with several layers of dielectric materials are shown in this paper. The analysis of those simulations, conducted on pseudo-vertical diodes protected by a field plate on a semi-resistive layer deposited on top of a dielectric, shows a great efficiency of such junction termination structures

Simulation and design of junction termination structures for diamond Schottky diodes

International audienceIn this paper, the first step of the design of a junction termination structure usable on diamond Schottky diodes is introduced. Through the collaboration of AMPERE and LAAS laboratories, a study of junction termination structures using field plates and semiresistive materials was carried out. Several results from simulations of P type Schottky diodes protected by MESA coated with several layers of dielectric materials are shown in this paper. The analysis of those simulations, conducted on pseudo-vertical diodes protected by a field plate on a semi-resistive layer deposited on top of a dielectric, shows a great efficiency of such junction termination structures

Using a two step plasma etching process for diamond power devices

International audienc

Electrical characteristics (I-V) of field plate protected vertical diamond Schottky diodes

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Study and optimization of a 600V Pseudo-vertical GaN-on-silicon rectifier by finite elements simulation

International audienceReal performance breakthrough have been demonstrated for high voltage, high power, high temperature and high frequency devices by using wide band-gap semiconductors, such as 4H-SiC, GaN and AlGaN, over the previously existing devices based on group-IV and III-V lower band-gap semiconductor material. One of the key devices for high power switching converter is a fast rectifier. 4H-SiC based Schottky diodes are now commercially available from many companies with breakdown voltage up to 1,7 kV. However, bulk SiC substrates are very expensive and the hetero-epitaxial SiC layers on low cost substrates have too many crystal defects. These are the main reasons for the ongoing research programs toward GaN based-rectifiers on Silicon substrate for medium voltage range applications (600 V < Vbr < 1.2 kV)