SiC和GaN电力电子器件的研究进展

与传统的Si基器件相比,SiC和GaN器件具有工作温度高、击穿电压高、开关速度快等优势,因此SiC和GaN材料是制备电力电子器件的理想材料。总结了近年来SiC和GaN电力电子器件的研究进展,包括二极管,MOSFET,JFET和BJT结构的SiC器件,以及SBD,PN结二极管,HEMT和MOSFET结构的GaN器件。     

浅析高温Ti4H-SiC肖特基势垒二极管的特性

SiC是新一代高温、高频、大功率和抗辐照半导体器件和集成电路的半导体材料,具有高击穿电场、高饱和电子漂移速率、高热导率及抗辐照能力强等一系列优点肖特基势垒二极管是实现各种SiC器件的基础,因此对SiC肖特基势垒二极管高温特性的研究具有十分重要的理论和实际意义。     

不同退火温度对4H SiC 金半接触的影响

采用高真空电子束蒸发法制作了基于4H SiC外延材料的肖特基二极管,其中欧姆接触材料为Ti/Ni,肖特基接触材料为Ni。常温下,电流-电压(I-V)测试表明Ni/4H SiC肖特基二极管具有良好的整流特性,热电子发射是其主要输运机理。对比分析不同快速退火温度下器件的I-V特性,实验结果表明875 ℃退火温度下欧姆接触特性最好,400 ℃退火温度下器件肖特基接触I-V特性最好,理想因子为1.447,肖特基势垒高度为1.029 eV。     

SiC肖特基二极管势垒不均匀分布理论与研究进展

碳化硅(SiC)半导体具有宽禁带、高临界击穿电场、高热导率等优异的性能,在高温、高频和大功率器件领域具有广阔的应用前景.SiC肖特基二极管是最早商用化的SiC器件,然而,由于决定金属接触性能的肖特基势垒无法得到有效控制,高性能的SiC欧姆接触和肖特基接触制备仍然是SiC肖特基二极管研制中的关键技术难题.基于此,首先对金...     

意法半导体发布2-40 A 1200 V SiC JBS二极管

<正>意法半导体(以下简称ST)近期发布了一款2-40 A1200 V的SiC JBS二极管,具有高转换率、高回收率、恒温特性,广泛用于碳化硅技术领域。ST表示,SiC二极管工艺线生产的器件具有最佳的正向电压(VF最低),设计人员可通过使用低额定电流和低成本的二极管实现高有效性和可靠性的电路设计。因此,SiC     

碳化硅器件发展概述

概要介绍了第三代半导体材料碳化硅(SiC)在高温、高频、大功率器件应用方面的优势,结合国际上SiC肖特基势垒二极管,PiN二极管和结势垒肖特基二极管的发展历史,介绍了SiC功率二极管的最新进展,同时对我国宽禁带半导体SiC器件的研究现状及发展方向做了概述及展望。     

一种新型SiC SBD的高温反向恢复特性

与传统硅基功率二极管相比,碳化硅肖特基势垒二极管(SiC SBD)可提高开关频率并大幅减小开关损耗,同时有更高的耐压范围.设计并制作了具有场限环结终端和Ti肖特基接触的1.2 kV/30 A SiC SBD器件,研究了该SiC SBD在100~300℃时的反向恢复特性.实验结果表明,温度每上升100℃,SiC SBD反向电压峰值增幅为5%左右,而反向恢复电流与反向恢复时间受温度影响不大;温度每升高50℃,反向恢复损耗功率峰值降低5%.实验结果表明该SiCSBD在高温下能够稳定工作,且具有良好的反向恢复特性,适用于卫星、航空和航天探测、石油以及地热钻井探测等需要大功率、耐高温和高速器件的领域.     

3C-SiC功率肖特基二极管特性的计算机分析

由描述功率肖特基二极管电学特性的基本方程出发，结合对典型整流电路效率、器件正向压降、反向耐压及温度特性等参数的数值分析，给出3C－SiC功率肖特基二极管折衷优化设计的理论依据。     

Pt/6H-SiC肖特基势垒二极管特性分析

采用直流磁控溅射法、Pt作肖特基接触的工艺，制作了N型6H—SiC肖特基势垒二极管，对肖特基势垒二极管的电学特性及温度特性进行了研究。实验结果表明，该器件具有很好的整流特性，反向电流小、击穿电压高，且在高温下器件波动很小，能够稳定地工作，适合于在高温(600℃)等恶劣环境下长期可靠地工作。     

英飞凌推出改进型第三代碳化硅肖特基二极管新产品

率先推出碳化硅（SiC）肖特基二极管的功率半导体供应商英飞凌科技股份有限公司近日在应用电源电子大会暨展览会（APEC）上推出第三代thinQ!^TM SiC肖特基二极管。全新thinQ!二极管在任何额定电流条件下都具备业界最低的器件电容．可在高开关频率和轻负载条件下提升整个系统的效率,从而帮助降低电源转换系统成本。     

Static and dynamic characterization of large-areahigh-current-density SiC Schottky diodes

The static and dynamic characteristics of large-area, high-voltage 4H-SiC Schottky barrier diodes are presented. With a breakdown voltage greater than 1200 V and a forward current in excess of 6 A at 2 V forward bias, these devices enable for the first time the evaluation of SiC Schottky diodes in practical switching circuits. These diodes were inserted into standard test circuits and compared to commercially available silicon devices, the results of which are reported here. Substituting SiC Schottky diodes in place of comparably rated silicon PIN diodes reduced the switching losses by a factor of four, and virtually eliminated the reverse recovery transient. These results are even more dramatic at elevated temperatures. While the switching loss in silicon diodes increases dramatically with temperature, the SiC devices remain essentially unchanged. The data presented here clearly demonstrates the distinct advantages offered by SiC Schottky rectifiers, and their emerging potential to replace silicon PIN diodes in power switching applications     

The influence of high-temperature annealing on SiC schottky diode characteristics

The influence of high temperature (up to 800C) annealing on the current-voltage characteristics of n-type 6H-SiC Schottky diodes is presented. Our experimental results indicate that high-temperature annealing can result in the improvement of the forw ard and reverse electrical characteristics of SiC Schottky diodes by repairing any leaky low barrier secondary diode parallel to the primary diode that may be present due to the barrier inhomogeneities at the Schottky contact interface.     

The guard-ring termination for the high-voltage SiC Schottkybarrier diodes

In this report, we propose the guard-ring structure as the edge termination for the high-voltage SiC Schottky barrier diodes. The local oxidation process is used to form the mesa of a p-n junction as the guard-ring. The comparison between the Al/Ti Schottky barrier diodes with and without the guard-ring indicates the effectiveness of the guard-ring to relax the electric field, from the results that the breakdown voltage is about two times larger with high yield     

Dual metal SiC Schottky rectifiers with low power dissipation

Nickel and titanium are the most commonly used metals for Schottky barrier diodes on silicon carbide (SiC). Ti has a low Schottky barrier height (i.e. 0.8 eV on 6H-SiC), whilst Ni has a higher barrier (i.e. 1.25 eV). Therefore, the first metal allows to achieve a low forward voltage drop V_F but leads to a high leakage current. On the other hand, the second one presents the advantage of a lower reverse leakage current but has also a high value of V_F. In this work, dual-metal-planar (DMP) Schottky diodes on silicon carbide are reported. The rectifying barrier was formed by using an array of micrometric Ti and Ni₂Si (nickel silicide) stripes. This low/high Schottky barrier allowed to combine the advantages of the two metals, i.e. to fabricate diodes with a forward voltage drop close to that of a Ti diode and with a level of reverse current comparable to that of a Ni₂Si diode. Under the application point of view, using this kind of barrier can lead to a reduction of the device power dissipation and an increase of the maximum operating temperature.     

High-voltage Ni- and Pt-SiC Schottky diodes utilizing metal fieldplate termination

We have fabricated 1 kV 4H and 6H SiC Schottky diodes utilizing a metal-oxide overlap structure for electric field termination. This simple structure when used with a high barrier height metal such as Ni has consistently given us good yield of Schottky diodes with breakdown voltages in excess of 60% of the theoretically calculated value. This paper presents the design considerations, the fabrication procedure, and characterization results for these 1 kV Ni-SiC Schottky diodes. Comparison to similarly fabricated Pt-SiC Schottky diodes is reported. The Ni-SiC ohmic contact formation has been studied using Auger electron spectroscopy and X-ray diffraction. The characterization study includes measurements of current-voltage (I-V) temperature and capacitance-voltage (C-V) temperature characteristics. The high-temperature performance of these diodes has also been investigated. The diodes show good rectifying behavior with ON/OFF current ratios, ranging from 10⁶ to 10 at 27°C and in excess of 10⁶ up to 300°C     

Improved Ni Schottky Contacts on <Emphasis Type="Italic">n</Emphasis>-Type 4H-SiC Using Thermal Processing

High-temperature processing was used to improve the barrier properties of three sets of n-type 4H-SiC Schottky diodes fabricated with Ni Schottky contacts. We obtained an optimum average barrier height of 1.78 eV and an ideality factor of 1.09 using current–voltage measurements on diodes annealed in vacuum at 500°C for 24 h. Nonannealed contacts had an average barrier height of 1.48 eV and an ideality factor of 1.85. The Rutherford backscattering spectra of the Ni/SiC contacts revealed the formation of a nickel silicide at the interface, accompanied by a substantial reduction in oxygen following annealing.     

JTE结构4H-SiC肖特基二极管的研究

借助半导体仿真软件Silvaco,仿真一种具有结终端扩展（JTE）结构的碳化硅（SiC）肖特基二极管（SBD）。其机理是通过JTE结构降低肖特基结边缘的电场集中效应,从而优化肖特基二极管的反向耐压能力。研究JTE区深度、宽度及掺杂浓度对碳化硅肖特基二极管的反向耐压的影响。通过优化结终端结构的结构参数使碳化硅肖特基二极管的反向耐压特性达到更好的性能要求。     

Behaviour of 1.2 kV SiC JBS diodes under repetitive high power stress

A methodology and a dedicated test-bench to evaluate the behaviour of SiC JBS diodes under repetitive high power stresses and surge currents have been developed and illustrated with JBS and Schottky 1.2 kV SiC diodes. The concept of dissipated energy versus the number of cycles is introduced to characterize the degradation evolution of the tested device. The sweeping current pulse technique offers the possibility to evaluate the effect of the self-heating on the I (V). This is especially relevant for JBS SiC diodes whose series resistance highly depends on the junction temperature. JBS diodes show a ×2.66 (×4.16) higher surge current capability at 25 °C (225 °C) than the pure Schottky diodes. The fabricated SiC JBS and Schottky diodes have been submitted to more than 300,000 power cycles at a dissipated energy of 0.7 J, showing no relevant degradation.