基于自支撑GaN和蓝宝石衬底AlGaN/GaN MISHEMT器件对比  

Comparation of AlGaN/GaN MISHEMTs on Free-Standing GaN and Sapphire Substrates

作　　者：李淑萍[1] 孙世闯 张宝顺[2] Li Shuping Sun Shichuang Zhang Baoshun(Suzhou Industrial Park Institute of Services Outsourcing , Suzhou 215123, China Suzhou Institute of Nano- Tech and Nano-Bionics （ S I NANO） , Chinese Academy of Sciences, Suzhou 215123, China Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China)

机构地区：[1]苏州工业园区服务外包职业学院,江苏苏州215123 [2]中国科学院苏州纳米技术与纳米仿生研究所,江苏苏州215123 [3]华中科技大学武汉光电国家实验室(筹),武汉430074

出　　处：《微纳电子技术》2017年第11期734-739,共6页Micronanoelectronic Technology

基　　金：国家自然科学基金青年科学基金资助项目(11404372);江苏省重点研发计划资助项目(BE2016084)

摘　　要：通过金属有机化学气相沉积(MOCVD)法,在氢化物气相外延(HVPE)自支撑GaN衬底和蓝宝石(0001)衬底上外延生长AlGaN/AlN/GaN结构的高电子迁移率晶体管(HEMT)材料,采用低压化学气相沉积SiN_x作为栅介质层,形成金属绝缘半导体高电子迁移率晶体管(MISHEMT)结构,对比研究了两种器件的材料性能和电学特性。阴极发光测试表明HVPE的自支撑GaN衬底缺陷密度可降至6×10~5 cm^(-2)量级。自支撑GaN衬底上AlGaN/GaN HEMT结构具有良好的表面形貌,其表面粗糙度R_a仅为0.51 nm,具有较大的源漏电极饱和电流I_(DS)=378 mA/mm和较高跨导G_m=47 mS/mm。动态导通电阻测试进一步表明,自支撑GaN衬底上同质外延生长的GaN缓冲层具有低缺陷密度,使AlGaN/GaN MISHEMT电流崩塌特性得到抑制。By the metal organic chemical vapor deposition （MOCVD） method, an A1GaN/GaN structure of high electron mobility transistors （HEMTs） was grown on free-standing GaN and sapphire （0001） substrates by hydride vapor phase epitaxy （HVPE）. With SiNx grown by the low pressure chemical vapor deposition as gate dielectric layer, the metal-insulator semiconductor high electron mobility transistor （MISHEMT） structure was prepared. The material and electri- cal properties of two kinds of the devices were compared. The cathodoluminescence test result shows that the defect density of the HVPE free-standing GaN substrate can reduce to 6 x 105 cm-2. The A1GaN/GaN HEMT structure grown on the free-standing GaN substrate has a smooth surface morphology with a surface roughness R. of 0. 51 nm, large saturation current of source and drain electrode of IDS= 378 mA/mm and large transconductance Gm= 47 mS/mm. The dynamic on-resistance measurements result indicates that the homoepitaxy GaN buffer layer on the free-standing GaN substrate has low defect density, and then the current collapse characteris- tic of the A1GaN/GaN MISHEMT is suppressed.

关 键 词：氢化物气相外延(HVPE)GaN衬底 金属有机化学气相沉积(MOcVD) AlGaN/ GaN金属绝缘半导体高电子迁移率晶体管(MIsHEMT) 同质外延 电流崩塌 

分 类 号：TN386[电子电信—物理电子学]