Electrical properties and structural optimization of GaN/InGaN/GaN tunnel junctions grown by molecular beam epitaxy  

作　　者：Jun Fang Fan Zhang Wenxian Yang Aiqin Tian Jianping Liu Shulong Lu Hui Yang 

机构地区：[1]School of Nano-Tech and Nano-Bionics,University of Science and Technology of China,Hefei 230026,China [2]Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China

出　　处：《Journal of Semiconductors》2024年第1期48-54,共7页半导体学报（英文版）

基　　金：supported by the National Key Research and Development Program of China (2017YFE0131500, 2022YFB2802801);the National Natural Science Foundation of China (61834008, U21A20493);the Key Research and Development Program of Jiangsu Province (BE2020004, BE2021008-1);the Suzhou Key Laboratory of New-type Laser Display Technology (SZS2022007)

摘　　要：The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases and the surface roughness of the samples increases.V-pits and trench defects were not found in the AFM images.p++-GaN/InGaN/n++-GaN TJs were investigated for various In content,InGaN thicknesses and doping concentration in the InGaN insert layer.The InGaN insert layer can promote good interband tunneling in GaN/InGaN/GaN TJ and significantly reduce operating voltage when doping is sufficiently high.The current density increases with increasing In content for the 3 nm InGaN insert layer,which is achieved by reducing the depletion zone width and the height of the potential barrier.At a forward current density of 500 A/cm^(2),the measured voltage was 4.31 V and the differential resistance was measured to be 3.75×10^(−3)Ω·cm^(2)for the device with a 3 nm p++-In_(0.35)Ga_(0.65)N insert layer.When the thickness of the In_(0.35)Ga_(0.65)N layer is closer to the“balanced”thickness,the TJ current density is higher.If the thickness is too high or too low,the width of the depletion zone will increase and the current density will decrease.The undoped InGaN layer has a better performance than n-type doping in the TJ.Polarization-engineered tunnel junctions can enhance the functionality and performance of electronic and optoelectronic devices.

关 键 词：GaN/InGaN/GaN tunnel junctions polarization-engineering molecular beam epitaxy 

分 类 号：TN304.054[电子电信—物理电子学]