物理气相传输法生长碳化硅单晶原生表面形貌研究  

As-grown Surface Morphologies of SiC Single Crystals Grown by PVT Method

作　　者：崔潆心 胡小波[3] 徐现刚[3] CUI Ying-Xin;HU Xiao-Bo;XU Xian-Gang(Microsystem and Terahertz Research Center,China Academy of Engineering Physics,Chengdu 610200,China;Institute of Electronic Engineering,China Academy of Engineering Physics,Mianyang 621999,China;State Key Laboratory of Crystal Materials,Shandong University,Jinan 250100,China)

机构地区：[1]中国工程物理研究院微系统与太赫兹研究中心,成都610200 [2]中国工程物理研究院电子工程研究所,绵阳621999 [3]山东大学晶体材料国家重点实验室,济南250100

出　　处：《无机材料学报》2018年第8期877-882,共6页Journal of Inorganic Materials

基　　金：科学挑战专题(TZ2018003)~~

摘　　要：晶体的生长原生面在一定程度上能反应出晶体生长机制和晶体缺陷分布的丰富信息。采用激光共聚焦显微镜偏光拼接技术和原子力显微镜对物理气相传输法生长的4H、6H-SiC单晶原生小面的表面形貌进行了观察和测试。偏光显微镜和原子力显微镜测试结果显示4H-SiC原生小面扩展后,其周边趋向于形成六边形的生长台阶;而6H-SiC原生小面扩展后,其周边趋向于形成圆形的生长台阶。基于Jackson双层界面模型,从热力学角度计算了4H、6H-SiC单晶的Jackson因子α分别为33.15和31.87,故导致4H、6H-SiC单晶原生小面台阶形貌差异的是生长界面的粗糙程度和生长温度。原生面上的微管缺陷是生长台阶的起源,借助原子力显微镜对多个微管进行了测试。由测试结果可知,微管直径分布在760 nm–6.0 um之间,相应的伯格斯矢量绝对值分布在5c^14c,微管直径与伯格斯矢量平方值的商D/B2分布在11.1~23.6 nm^(–1)之间,即通过原子力显微镜测试获得的微管结构数据不严格遵守Frank理论。As-grown surface of single crystal can reflect abundant information including crystal growth mechanism and defect distribution of the single crystal after growth. The as-grown surface morphologies of 4H-SiC and 6H-SiC single crystals were observed and measured by laser confocal microscope DIC splicing technique and atomic force microscope（AFM）. It is found that as-grown 4H-SiC surface tends to appear hexagonal growth steps, while the as-grown 6H-SiC surface tends to appear circular growth steps. Based on Jackson model and thermodynamics theory, Jackson factors of the 4H-SiC and 6H-SiC single crystals are calculated to be 33.15 and 31.87, respectively. Therefore, the surface morphology difference between 4H-SiC and 6H-SiC is caused by the roughness of growth interface and crystal growth temperature. The micropipe on the as-grown surface is the origin of growth steps and multiple micropipes on the as grown surface were measured by AFM. Their diameters are in the range of 760 nm-6.0 μm, and the corresponding absolute values of Burgers vector are in the range of 5 c-14 c. Through structure characterization and statistical analysis, the values of micropipe diameters divided by squares of the burgers vectors（D/B2） are in the range of 11.1 nm-1-23.6 nm^（–1）, which means the structure data of these micropipes obtained by AFM cannot strictly obey the Frank theory.

关 键 词：碳化硅 原生小面 微管结构 

分 类 号：O766[理学—晶体学]