碳化硅金属-半导体双极型晶体管的研究

项目名称： 碳化硅金属-半导体双极型晶体管的研究

项目编号： No.60876061

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 轻工业、手工业

项目作者： 张玉明

作者单位： 西安电子科技大学

项目金额： 40万元

中文摘要： 在功率半导体器件中，4H-SiC双极晶体管（BJTs）作为一种双载流子工作器件，越来越受到人们的重视，国内外的许多科研机构已经相继展开了从器件结构到工艺实验等各方面的研究。本项目的研究工作基于4H-SiC的材料特性和器件基本工作原理，创造性的提出了一种新型的金属-发射极双极晶体管以及双外延基区4H-SiC双极晶体管结构。其中基区结构采用连续二次外延的方式形成。依据漂移扩散理论，求解了这两种器件的基区渡越时间的解析表达式，并根据该解析模型，对该双极晶体管的基区结构进行了重点研究。依据正交实验结果，针对包括掺杂浓度及厚度在内的多个参数进行了优化设计。以提高器件击穿电压为目的，器件结构设计中引入了多种不同的结终端结构，通过模拟计算对不同结终端结构的参数进行了优化设计，包括掺杂浓度、离子注入深度、注入剂量和能量的计算等。最后还对双外延基区器件进行了版图设计并投片实验，优化的ICP刻蚀工艺能有效的保证发射区台面刻蚀精度。测试结果显示当IC=28.6mA (JC=183.4A/cm2)时，共发射极电流增益β6.8，比导通电阻Rsp-on为32.3mΩm2，基极开路击穿电压BV为410V。

中文关键词： 4H-SiC；双极晶体管；金半接触；电流增益

英文摘要： Among the high power devices, 4H-SiC Bipolar Junction Transistors(BJTs) have been a subject of more and more study.This research work presents a new type of metal-emitter BJTs and double-base-epilayer 4H-SiC BJTs, and the design, fabrication and testing of these typical BJTs has been demonstrated. According to the drift-diffusion theory, the analytical model of the base transit time of these two structures have been established in our research work.And the base configuration of these typical devices have been investigated selectively based on this model. Followed by the orthogonal experimental results, the device parameters of the base region including the doping concentration and the thickness have been optimized. In order to increase the breakdown voltage, two junction termination structures have been introduced in this device configuration. The parameters including doping concentration, the depth of the ion implantation, the implantation dosage and energy are calculated for different JTT structure. Based on the theoretical achievements antecedent, the layout is designed and the fabrication is proceeded. An improved method that controls the precision of the ICP etching is put forward. The measured results show that the max gain is 16.8 when IC=28.6mA(JC=183.4A/cm2) and it increases first and then decreases with the collector current density increasing. The specific on-resistance(Rsp-on) is 32.3mΩm2 and the blocking voltage with open base is 410V.

英文关键词： 4H-SiC; Bipolar Junction Transistors; Metal-Semiconductor Contact;Current Gain