氨热法GaN单晶生长的位错密度演变研究  

Dislocation Density Evolution Study of GaN Single Crystal Growth by Ammonothermal Method

作　　者：夏政辉 李腾坤 任国强[1] 解凯贺 卢文浩 李韶哲 郑树楠[1] 高晓冬 徐科[1,3,4] XIA Zhenghui;LI Tengkun;REN Guoqiang;XIE Kaihe;LU Wenhao;LI Shaozhe;ZHENG Shunan;GAO Xiaodong;XU Ke(Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China;School of Nano Science and Technology Institute,University of Science and Technology of China,Hefei 230026,China;Suzhou Nanowin Science and Technology Co.,Ltd.,Suzhou 215123,China;Jiangsu Institute of Advanced Semiconductors,Ltd.,Suzhou 215000,China)

机构地区：[1]中国科学院苏州纳米技术与纳米仿生研究所,苏州215123 [2]中国科学技术大学纳米科学与技术学院,合肥230026 [3]苏州纳维科技有限公司,苏州215123 [4]江苏第三代半导体研究院,苏州215000

出　　处：《人工晶体学报》2024年第3期480-486,共7页Journal of Synthetic Crystals

基　　金：国家重点研发计划(2021YFB3602000,2022YFB3605202);国家自然科学基金(62074157,62104246);江苏省重点研发计划(BE2021008)。

摘　　要：氮化镓单晶具有高击穿电压、直接带隙、高饱和电子漂移速率、良好的化学稳定性等特性,在光电子器件和大功率电子器件中有广泛的应用。然而异质外延氮化镓会产生高位错密度,限制了氮化镓基器件的性能发挥。本研究以HVPE-GaN为籽晶,采用氨热法生长了氮化镓单晶,利用扫描电子显微镜(SEM),光学显微镜和湿法腐蚀研究了氨热法氮化镓单晶籽晶区至侧向生长区的位错演变。研究结果表明,侧向生长区的氮化镓单晶位错密度明显低于籽晶区,侧向生长超过25μm后,位错密度降低2个数量级。Gallium nitride(GaN)single crystal has the characteristics of high breakdown voltage,direct band gap,high saturated electron drift rate,good chemical stability,etc.,and has been widely used in optoelectronic devices and high-power electronic devices.However,the heteroepitaxial of GaN produces a high dislocation density,which limits the performance of GaN devices.In this study,GaN single crystal was grown by ammonothermal method using HVPE-GaN as a seed crystal.The dislocation evolution from the seed crystal region to the lateral growth region of GaN single crystal was studied by scanning electron microscopy(SEM),optical microscopy and wet etching.The results show that the dislocation density of GaN single crystal in the lateral growth region is obviously lower than that in the seed crystal region,and the dislocation density decreases by 2 orders of magnitude when the lateral growth exceeds 25μm.

关 键 词：氮化镓单晶 氨热法 侧向生长 位错密度 腐蚀坑 

分 类 号：O77[理学—晶体学] O78