在4H-SiC中的位移安排及其对当地的晶格特性的影响
Melissa Roder1, Johannes Steiner2, Peter Wellmann2
1Crystallography, Albert-Ludwigs University Freiburg, Hermann-Herder Strasse 5, Freiburg, Baden-Württemberg 79104, Germany.
Journal of applied crystallography
|June 7, 2023
概括
同步白光X射线拓 (SWXRT) 揭示了4H-碳化 (4H-SiC) 晶圆中类似的位移安排,表明在生长过程中存在一致的传播. 这种方法可以详细地绘制失位类型和密度的地图.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 4H-碳化 (4H-SiC) 是高功率电子产品的关键宽带间隙半导体.
- 了解脱位形成和传播对于改善晶体质量和设备性能至关重要.
- 之前的表征方法在完整的晶圆映射和个别失位识别方面存在局限性.
研究的目的:
- 研究4H-SiC散体晶体在生长过程中的脱位形成和传播.
- 建立一种全面的方法,以对位移类型,密度和分布进行完整的晶圆映射.
- 为了将失位特征与晶格张力和倾斜相关联.
主要方法:
- 在反射和传输几何学中使用同步白光束X射线拓 (SWXRT).
- 使用CCD摄像系统在00012反射几何学中绘制全晶片映射.
- 高分辨率的X射线衍光度测量在对称0004反射中的互换空间图 (RSM) 测量.
主要成果:
- SWXRT 首次实现了 4H-SiC 中脱位安排的完整晶圆映射,识别了个别脱位,包括线程螺丝脱位.
- 种子末端和帽子末端的晶圆表现出类似的位移安排,这表明在生长过程中不断传播.
- RSM测量表明,晶格的拉伸和倾斜取决于占主导地位的脱位类型,密度和方向.
结论:
- 在4H-SiC批量晶体中的脱位传播是整个生长过程中的连续过程.
- 带有CCD检测的SWXRT提供了一个强大的工具,用于详细描述晶体缺陷.
- 局部晶格状网的特性受到异位的特定类型和安排的显著影响.
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