• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Investigation of extended defects in silicon carbide and gallium nitride by scanning techniques.
【24h】

Investigation of extended defects in silicon carbide and gallium nitride by scanning techniques.

机译：通过扫描技术研究碳化硅和氮化镓中扩展缺陷。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Silicon carbide and gallium nitride are wide bandgap compound semiconductors suitable for high breakdown voltage, high power, and high frequency device applications. The major drawback is the effects of structural defects, which often limit the performance, yield, and reliability of the fabricated devices. Effective and rapid nondestructive characterization scanning techniques are required to identify and study the defects.; An electron beam-induced current (EBIC) investigation of the grown-in defects in 4H-SiC epilayers confirmed the significant effect of extended defects on Schottky diode ideality, barrier height, and reverse breakdown voltage. The device parameters degrade gradually as the number of defects visualized by EBIC increases. The defects were also observed by molten KOH etching and consist mainly of basal-plane and threading dislocations; and dislocation clusters. The EBIC images were compared with conductive atomic force microscopy (CAFM) images of leakage current associated with the dislocations.; Polytypic 3C quantum wells (double Shockley stacking faults) are spontaneously generated during thermal processing of moderately doped 4H-SiC epilayers grown on substrates with heavy n-type doping above ∼3x10 19cm-3. They intersect the wafer surface as straight lines, due to the 8∩ misorientation of the wafer from the c-axis. The electric fields, charge, and conductivity associated with these intersections were studied in detail. These intersections appear as bright lines in secondary electron images. Electrostatic force microscopy (EFM), scanning Kelvin probe microscopy (SKPM), and CAFM also produce clear images of the quantum well intersections. The results are compared to two-dimensional electrostatic simulations.; Gallium nitride epitaxial layers grown on 6H-SiC substrates were studied using the SEM, cathodoluminescence (CL), atomic force microscopy (AFM), and CAFM techniques. These layers exhibit a columnar subgrain structure, which depends on layer thickness, doping, and substrate preparation. These dependencies are investigated and explained.; Folded prismatic stacking faults formed in GaN epitaxial layers grown on 6H-SiC substrates offcut 3.5° towards the [1-210] direction were studied using CL, SEM, AFM and CAFM. Trenches due to the intersections of these faults with the surface are observed by SEM and AFM, and correlated to monochromatic CL imaging to identify luminescence features related to stair-rod dislocations and the associated lattice disconnections.
机译：碳化硅和氮化镓是适用于高击穿电压，高功率和高频设备应用的宽带隙化合物半导体。主要缺点是结构缺陷的影响，通常会限制所制造器件的性能，良率和可靠性。需要有效，快速的非破坏性特征扫描技术来识别和研究缺陷。电子束感应电流（EBIC）对4H-SiC外延层中缺陷的研究表明，扩展缺陷对肖特基二极管的理想性，势垒高度和反向击穿电压具有显着影响。随着EBIC可视化缺陷数量的增加，器件参数逐渐降低。缺陷还通过熔融KOH蚀刻观察到，主要由基面和螺纹位错组成。和位错簇。将EBIC图像与与位错相关的泄漏电流的导电原子力显微镜（CAFM）图像进行了比较。多型3C量子阱（双重Shockley堆垛层错）是在对厚约3x10 19cm-3的n型重掺杂衬底上生长的中等掺杂4H-SiC外延层进行热处理时自发产生的。由于晶片相对于c轴的8°错位，它们以直线与晶片表面相交。详细研究了与这些交叉点相关的电场，电荷和电导率。这些交点在二次电子图像中显示为亮线。静电力显微镜（EFM），扫描开尔文探针显微镜（SKPM）和CAFM也可以产生清晰的量子阱相交图像。将结果与二维静电仿真进行比较。使用SEM，阴极发光（CL），原子力显微镜（AFM）和CAFM技术研究了在6H-SiC衬底上生长的氮化镓外延层。这些层表现出柱状亚晶结构，这取决于层厚度，掺杂和衬底制备。对这些依赖性进行了调查和解释。使用CL，SEM，AFM和CAFM研究了在6H-SiC衬底上生长的GaN外延层中形成的折叠棱柱堆叠缺陷，该衬底朝[1-210]方向偏移了3.5°。通过SEM和AFM观察到由于这些断层与表面的相交而产生的沟槽，并与单色CL成像相关联，以识别与楼梯杆位错和相关的晶格断开相关的发光特征。

著录项

  • 作者

    Mikhov, Mikhail K.;

  • 作者单位

    Arizona State University.;

  • 授予单位 Arizona State University.;
  • 学科 Engineering Electronics and Electrical.; Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2005
  • 页码 115 p.
  • 总页数 115
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 无线电电子学、电信技术;工程材料学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号