高压SiC PiN器件的研制与静动态特性研究

发布时间：2018-02-24 05:40

本文关键词： 碳化硅 PiN二极管制造工艺载流子寿命　出处：《电子科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：第三代半导体中的碳化硅(Silicon Carbide,SiC)材料,以拥有许多独特而优越的物理特性,诸如宽禁带,高热导率,高临界击穿电场,高电子漂移速度等而备受关注。在功率半导体器件领域,随着Si基器件技术的完备,取得新突破变得比较困难,SiC基器件相比Si基器件有着更高的耐压,更高功率密度,更快的开关速度等优势,拥有更宽广的应用前景和研究价值。国内的SiC功率器件研究起步较晚,研究水平落后于国际先进水平。本文以高压4H-SiC PiN二极管为研究对象,对其结构进行了设计和优化,并结合国内工艺试验条件,进行流片实验和测试分析,旨在为国内高压4H-SiC PiN二极管的研究提供参考,研究的主要内容分为三部分。首先,通过Silvaco半导体数值仿真软件,设计优化了4500V高压SiC PiN二极管结构。其中,元胞漂移区厚度为40μm,击穿电压为5600V,正向电流密度为100A/cm~2时的开启电压为3.5V。器件终端采用台面结终端拓展(Junction Termination Extension,JTE)型结终端结构,终端效率为96%。通过仿真研究了高压SiC PiN二极管的反向恢复特性。针对SiC PiN二极管的电导调制问题,研究了SiC材料中深能级对载流子寿命的影响,并通过仿真验证了不同载流子寿命下SiC PiN二极管的正向导通特性变化。其次,开展了高压SiC PiN二极管的关键制造工艺技术研究,优化开发出:高质量、低损伤、无微沟槽的SiC台面ICP刻蚀工艺技术,以及低比接触电阻率的P型和N型SiC材料的金属-半导体欧姆接触工艺技术。通过关键制造工艺技术的研发,获得了角度31~49°,高度为2μm的Si C台面结果和比接触电阻率为1e-6Ω·cm~2的N型欧姆接触,5e-5Ω·cm~2的P型的欧姆接触结果。最后,制定了高压SiC PiN二极管的工艺流程,进行了高压SiC PiN二极管的流片实验研制,并对实验样品进行了测试与分析。测试结果表明:SiC PiN二极管的正向导通压降约为3.4V@100A/cm~2,正向导通电压4V时正向导通电流11A,反向击穿电压大于4700V。
[Abstract]:The third generation of semiconductor silicon carbide (Silicon Carbide, SiC) materials, to have many unique and superior physical properties, such as wide band gap, high thermal conductivity, high breakdown field, high electron drift velocity is attracting more and more attention. In the field of power semiconductor devices, devices with Si based technology breakthroughs become complete, more difficult, SiC based devices compared to Si based devices have a higher voltage, higher power density, faster switching speed and other advantages, has broad application prospect and the research value. The research started relatively late in China SiC power devices, research lags behind the international advanced level. Based on the 4H-SiC PiN high voltage diode the object of study, has carried on the structure design and optimization, and combining the domestic technology test conditions, carried out experiments and analysis, to provide reference for the research of domestic high voltage 4H-SiC PiN diode, research The main content is divided into three parts. First, through the Silvaco numerical simulation software to optimize the design of semiconductor, 4500V high voltage SiC PiN diode structure. The thickness of the cellular drift region is 40 m, the breakdown voltage is 5600V, current density of 100A/cm~2 positive turn-on voltage is 3.5V. when the device terminal node terminal expansion (using the table Junction Termination Extension, JTE) junction termination structure, terminal efficiency for 96%. high voltage SiC PiN diode reverse recovery characteristics is studied through simulation. Aiming at the problem of SiC conductivity modulation of PiN diode, the effect of SiC material of deep level on carrier lifetime, and verified by simulation under different positive conduction carrier lifetime PiN diode SiC through the characteristic change. Secondly, the key of high voltage SiC PiN diode manufacturing technology research, optimization development: high quality, low damage, SiC ICP micro groove of the table Etching technology, and is lower than that of the P type and N type SiC material contact resistance of metal semiconductor ohmic contact technology. Through the development of key manufacturing technology, the 31~49 angle, the height is Si C 2 m and the surface contact resistivity of 1e-6. Cm~2 and N type ohmic contact the results of P, ohmic contact type 5e-5. Cm~2. Finally, we design the process of high voltage SiC PiN diode, developed high voltage SiC PiN diode chip experiment, and the experimental samples were tested and analyzed. The test results show that the SiC PiN diode forward voltage drop of about 3.4V@100A/cm~2, the positive guide through the forward conduction voltage 4V current 11A, the reverse breakdown voltage is higher than 4700V.

【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN303

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