低LIGBT衬底漏电流新结构研究

发布时间：2018-01-24 19:58

本文关键词： LIGBT 隔离衬底漏电流温度击穿电压　出处：《南京邮电大学》2016年硕士论文　论文类型：学位论文

【摘要】：LIGBT作为一类重要的栅控双极功率器件,既具有MOSFET的控制功率小、输入阻抗高、驱动电路简单、开关速度高的优点,又有双极型功率晶体管的饱和压降低、电流密度大、电流处理能力强的优点,因此LIGBT器件被广泛地应用在各种功率集成电路以及电力电子系统中。但在工作中,由于电导调制作用,阳极会向漂移区注入大量空穴,其中部分空穴会在正漏极电压作用下直接注入到衬底,从而产生严重的衬底漏电流,影响电路性能。为降低LIGBT的衬底漏电流,本文提出如下两类新结构:(1)针对自热效应严重,击穿电压低的的问题,提出了分层SO ILIGBT结构:新结构引入了埋氧层阳极和中间窗口,通过利用衬底参与承担电压体和利用硅窗口传导热量,提高了整个器件的耐受电压并且降低了自热效应。仿真结果表明:新结构的击穿电压提高1.5倍以上,工作时的热点温度下降15K以上,同时衬底漏电流低至7×10-12A/μm,开关速度基本不变。(2)针对第一种结构工艺复杂,电流导通能力不够强的问题,提出了双通道SO ILIGBT,新结构引入了双栅结构,并且进一步缩短埋氧层的长度,通过增加导电通道的方法,提高了电流导通能力,仿真结果表明,新结构的击穿电压达到400V左右,饱和电流浓度最高达到3.7A/μm,同时衬底漏电流在7×10-12A/μm以下,开关速度基本不变。
[Abstract]:As a kind of important gate controlled bipolar power device, LIGBT has the advantages of low control power, high input impedance, simple drive circuit and high switching speed of MOSFET. The bipolar power transistor has the advantages of low saturation voltage, high current density and strong current processing ability. Therefore, LIGBT devices are widely used in various power integrated circuits and power electronic systems, but in operation, the anode will inject a large number of holes into the drift region due to the effect of conductance modulation. Some of the holes will be injected directly into the substrate under the positive drain voltage, resulting in serious substrate leakage current, which will affect the circuit performance. In order to reduce the substrate leakage current of LIGBT. In this paper, two kinds of new structure: 1) aiming at the serious self-heating effect and low breakdown voltage, a layered so ILIGBT structure is proposed: the buried oxygen layer anode and the middle window are introduced into the new structure. By using substrate to take part in the voltage body and using silicon window to conduct heat, the withstand voltage of the whole device is improved and the self-heating effect is reduced. The simulation results show that the breakdown voltage of the new structure is increased by more than 1.5 times. At the same time, the substrate leakage current is as low as 7 脳 10 ~ (-12) A / 渭 m, and the switching speed is almost unchanged. Because the current conduction ability is not strong enough, the double channel so ILIGBT is put forward. The new structure introduces the double gate structure, and further shortens the length of the buried oxygen layer by increasing the conductive channel. The simulation results show that the breakdown voltage of the new structure is about 400V, and the saturation current concentration is up to 3.7A / 渭 m. At the same time, the substrate leakage current is below 7 脳 10-12 A / 渭 m, and the switching speed is almost unchanged.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN322.8

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