AlGaN/GaN横向肖特基势垒二极管抗浪涌电流特性与封装方案  

Current Surging Characteristics and Packaging Methods for Lateral AlGaN/GaN Schottky Barrier Diodes

作　　者：冯威 徐尉宗 周峰 曾昶琨 任芳芳[1] 陆海[1] Feng Wei;Xu Weizong;Zhou Feng;Zeng Changkun;Ren Fangfang;Lu Hai(School of Electronic Science and Engineering,Nanjing University,Nanjing 210046,China)

机构地区：[1]南京大学电子科学与工程学院,南京210046

出　　处：《半导体技术》2022年第5期354-359,396,共7页Semiconductor Technology

基　　金：国家自然科学基金资助项目(61921005,62004099);江苏省自然科学基金资助项目(BK20201253)。

摘　　要：基于AlGaN/GaN异质结构的横向肖特基势垒二极管(SBD)在新一代功率电子技术中具有应用潜力。而面对复杂电气环境中的电流过冲及振荡效应,抗浪涌电流能力是器件可靠工作的重要保障。首先通过对混合阳极结构的优化,降低了AlGaN/GaN基SBD的开启电压(0.22 V),并提高了器件正向导通能力;在此基础上,通过半正弦脉冲电流产生电路评估了器件的抗浪涌电流能力,发现采用引线键合封装的器件可承受的最大浪涌电流密度约为250 A/cm^(2),这一电流强度主要受限于肖特基电极边缘电流拥挤效应导致的热击穿。为提高近表面器件沟道的散热能力,采用了倒装的封装方式。实验证实倒装封装可以有效抑制热集聚效应,并提高器件的抗浪涌电流能力。AlGaN/GaN hetero-structure based lateral Schottky barrier diodes(SBDs)are emerging as promising candidates for new-generation power electronic applications,where the critical operation environment with current overshoot and oscillation effect require devices with high ruggedness against current surges.Firstly,hybrid anode structure was optimized to obtain a low turn-on voltage(0.22 V)and thus to enhance the forward conduction performance of the AlGaN/GaN-based SBDs.Subsequently,current surging capability of the devices was evaluated with the half-sine current-pulse generation circuit,where the device with normal wire-bonding package exhibits a maximum tolerable surge current density of about 250 A/cm^(2).The current level was found to be limited by the thermal breakdown caused by the current crowding effect at the Schottky electrode edge.Correspondingly,to favor the thermal conduction from the near-surface channel,flip-chip package was adopted and proved effective in alleviating the thermal accumulation effect and enhancing the current surging capability of the diodes.

关 键 词：AlGaN/GaN异质结构 肖特基势垒二极管(SBD) 浪涌电流 热效应 倒装封装 

分 类 号：TN311.7[电子电信—物理电子学]