具有均匀凹槽势垒结构的横向AlGaN/GaN高电子迁移率晶体管  

Transverse AlGaN/GaN high electron mobility transistors with uniform grooves barrier structures

作　　者：田雨 陈永和[1] 代一丹 刘子玉 马旺 TIAN Yu;CHEN Yonghe;DAI Yidan;LIU Ziyu;MA Wang(Guangxi Key Laboratory of Precision Navigation Technology and Application,Guilin University of Electronic Technology,Guilin 541004,China)

机构地区：[1]桂林电子科技大学,广西精密导航技术与运用重点实验室,广西桂林541004

出　　处：《桂林电子科技大学学报》2021年第4期266-272,共7页Journal of Guilin University of Electronic Technology

基　　金：国家自然科学基金(6216030144);广西自然科学基金(2018GXNSFAA138025);桂林电子科技大学研究生教育创新计划(桂科AD18281037)。

摘　　要：为了改善传统AlGaN/GaN HEMT器件的表面电场、温度分布,提升器件击穿电压和稳定性,提出了一种具有均匀凹槽势垒(UGB)的新型AlGaN/GaN HEMT器件结构。UGB-AlGaN/GaN HEMT结构通过在栅电极和漏电极之间引入均匀分布的凹槽AlGaN势垒,降低了AlGaN层极化强度,导致沟道2DEG浓度下降,形成低浓度的2DEG区域,使器件沟道2DEG分布由均匀分布变成凹槽台阶状分布,从而调节器件的表面电场。利用电场调制效应在凹槽右侧形成新的电场峰值,有效降低栅极边缘的高峰电场。同时,优化器件沟道表面温度分布,使UGB-AlGaN/GaN HEMT表面温度分布更均匀。Silvaco TCAD仿真结果表明,器件在关态漏极高压下,均匀凹槽AlGaN势垒能够调节HEMT器件的表面电场分布,从而保证了栅电极与漏电极距离为10μm时UGB-AlGaN/GaN HEMT器件能够达到821 V的击穿电压,是常规器件击穿电压(260 V)的3.1倍。同时,UGB-AlGaN/GaN HEMT器件的特征导通电阻仅为0.87 mΩ·cm^(-2),因此获得了高达772 MW·cm^(-2)的品质因数。基于新型均匀凹槽势垒结构的HEMT器件具有较高击穿电压,同时保持较低的特征导通电阻及良好的温度特性,这使得该结构在高功率电子元器件领域有很好的应用前景。In order to improve the surface electric field and temperature distribution of conventional AlGaN/GaN HEMT devices and enhance the breakdown voltage and stability of the devices, a new AlGaN/GaN HEMT device structure with uniform groove potential barrier(UGB) is proposed.The UGB-AlGaN/GaN HEMT structure reduces the polarization intensity of the AlGaN layer by introducing a uniformly distributed notch AlGaN barrier between the gate electrode and the drain electrode, resulting in a decrease in the channel 2DEG concentration and the formation of a low concentration 2DEG region, which changes the channel 2DEG distribution of the device from a uniform distribution to a notch step-like distribution, thereby regulate the surface electric field of the device. The electric field modulation effect is used to form a new electric field peak on the right side of the notch to effectively reduce the peak electric field at the gate edge. At the same time, the device channel surface temperature distribution is optimized to make the UGB-AlGaN/GaN HEMT surface temperature distribution more uniform simulation results of Silvaco TCAD show that the uniform notch AlGaN barrier can regulate the surface electric field distribution of the HEMT device under the high voltage of the off-state drain, thus ensuring the surface electric field distribution of the UGB-AlGaN/GaN HEMT device with the distance between the gate electrode and the drain electrode of 10 μm. AlGaN/GaN HEMT devices with a 10 μm distance between the gate electrode and the drain electrode can achieve a breakdown voltage of 821 V, which is 3.1 times higher than the breakdown voltage(260 V) of conventional devices. At the same time, the characteristic on-resistance of UGB-AlGaN/GaN HEMT devices is only 0.87 mΩ·cm^(-2), thus achieving a quality factor of up to 772 MW·cm^(-2). The HEMT devices based on the new uniform notch barrier structure have a high breakdown voltage while maintaining a low characteristic on-resistance and good temperature characteristics, which makes

关 键 词：ALGAN/GAN 凹槽势垒 电场 击穿 

分 类 号：TN386.1[电子电信—物理电子学]