Synchrotron Topography Studies of Growth and Deformation-Induced Dislocations in 4H-SiC
Synchrotron Topography Studies of Growth and Deformation-Induced Dislocations in 4H-SiC
复制标题
4H-SiC 中生长和变形引起的位错的同步加速器形貌研究
DOI：
10.1557/opl.2012.1141
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
M. Loboda
中科院分区：
文献类型：
--
作者：
M. Dudley;H. Wang;Fangzhen Wu;S. Byrappa;S. Shun;B. Raghothamachar;E. Sanchez;G. Chung;D. Hansen;S. Mueller;M. Loboda
同步加速器形貌研究介绍了 4H-SiC 单晶中生长位错和变形诱导位错的行为。生长位错包括线方向近似沿 c 的螺纹取向位错，伯格矢量为 a 、 c 和 n a + m c （其中 n 和 m 为整数），而变形引起的位错包括线方向局限于基面的位错，伯格矢量为 a 和肖克利部分位错，伯格矢量为 1/3，以及线方向在 {1-100} 棱柱面内的位错，伯格矢量为一个。讨论了导致生长位错成核的过程以及在可逆过程中晶体生长期间它们在基面上的偏转。后一过程可以导致偏转生长位错的片段转变为形变诱发位错。在某些情况下，这可能会通过跳跃弗兰克-里德源机制导致位错倍增，而在其他情况下，可能会导致单个肖克利部分位错的运动，从而导致肖克利堆垛层错扩展。研究还提出了螺纹生长位错与伯格矢量的 c 分量之间的相互作用，该相互作用是由爬升过程促进的，而爬升过程是由与非平衡空位浓度的相互作用介导的。这可能导致发生完全或部分位错伯格斯矢量湮灭的反应。
Synchrotron topography studies are presented of the behavior of growth dislocations and deformation-induced dislocations in 4H-SiC single crystals. The growth dislocations include those in threading orientation with line directions approximately along c with Burgers vectors of a , c , and n a + m c (where n and m are integers) while the deformation-induced dislocations include those with line directions confined to the basal plane with Burgers vectors of a and Shockley partial dislocations with Burgers vectors of 1/3 as well as those with line directions in the {1-100} prismatic planes with Burgers vectors of a . Processes leading to the nucleation of the growth dislocations are discussed as well as their deflection onto the basal plane during crystal growth in a reversible process. This latter process can lead to the conversion of segments of the deflected growth dislocations into deformation induced dislocations. In some cases this can lead to dislocation multiplication via the Hopping Frank-Read source mechanism and in others to the motion of single Shockley partial dislocations leading to Shockley stacking fault expansion. Studies are also presented of interactions between threading growth dislocations with c -component of Burger’s vector facilitated by climb processes which are mediated by interactions with non-equilibrium concentrations of vacancies. This can lead to reactions whereby complete or partial dislocation Burgers vector annihilation occurs.