GaN单晶衬底上同质外延界面杂质的研究  

Impurities of Homoepitaxy Interface on Bulk GaN Substrate

作　　者：邵凯恒 夏嵩渊 张育民 王建峰[1,2,4,5] 徐科[1,2,4,5] SHAO Kaiheng;XIA Songyuan;ZHANG Yumin;WANG Jianfeng;XU Ke(School of Nano-Tech and Nano-Bionics,University of Science and Technology of China,Hefei 230026,China;Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China;School of Physical Science and Technology,Shanghai Tech University,Shanghai 201210,China;Suzhou Nanowin Science and Technology Co.,Ltd.,Suzhou 215123,China;Key Laboratory of Nanophotonic Materials and Devices,Chinese Academy of Sciences,Suzhou 215123,China)

机构地区：[1]中国科学技术大学纳米技术与纳米仿生学院,合肥230026 [2]中国科学院苏州纳米技术与纳米仿生研究所,苏州215123 [3]上海科技大学物质科学与技术学院,上海201210 [4]苏州纳维科技有限公司,苏州215123 [5]中国科学院纳米光子材料与器件重点实验室,苏州215123

出　　处：《人工晶体学报》2021年第3期441-446,共6页Journal of Synthetic Crystals

基　　金：国家重点研发计划(2017YFB0404101,2017YFB0403000);国家自然科学基金(61704187);中国科学院前沿科学重点研究计划(QYZDB-SSW-SLH042)。

摘　　要：氮化镓单晶衬底上的同质外延具有显著的优势,但是二次生长界面上的杂质聚集一直是困扰同质外延广泛应用的难题,特别是对电子器件会带来沟道效应,对激光器应用会影响谐振腔中的光场分布。本文通过金属有机化合物化学气相沉积(MOCVD)生长的原位处理,实现了界面杂质聚集的有效抑制。研究发现,界面上的主要杂质是C、H、O和Si,其中C、H、O可以通过原位热清洗去除;界面Si聚集的问题主要是由衬底外延片保存过程中暴露空气带来的,其次是氮化镓衬底中Si背底浓度,在外延过程中,生长载气对氮化镓单晶衬底不稳定的N面造成刻蚀,释放的杂质元素会对二次生长界面产生影响,本文较系统地阐明了界面杂质的形成机制,并提出了解决方案。Homoepitaxy on bulk GaN substrate has significant advantages.However,accumulation of impurities on the regrowth interface has always been a problem that plagues the wide application of homoepitaxial,especially for electronic devices,which will bring channel effect,and for laser applications,which will affect the light field distribution in the resonator.In this paper,the in-situ treatment of metal-organic chemical vappor deposition(MOCVD)growth has achieved effective inhibition of the accumulation of interfacial impurities.The study found that the main impurities on the interface are C,H,O and Si,of which C,H,O can be removed by in-situ thermal cleaning.The problem of interface Si accumulation is mainly caused by exposure to air during the preservation of the substrate.During the growth process,the etching of the substrate by the carrier gas will release impurity elements which will accumulate at the regrowth interface.High Si background content and unstable N face of the GaN substrate are also sources of regrowth interface impurities.This paper systematically clarified the formation mechanism of interface impurities and proposed solutions.

关 键 词：氮化镓衬底 二次生长界面 界面杂质 杂质来源 同质外延 Si聚集 

分 类 号：O734[理学—晶体学] TN304[电子电信—物理电子学]