Aligned Self-Organization Induced by Epitaxial Stress and Shear Deformation in Jahn-Teller Spinel ZnMnGaO4
Aligned Self-Organization Induced by Epitaxial Stress and Shear Deformation in Jahn-Teller Spinel ZnMnGaO4
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Jahn-Teller 尖晶石 ZnMnGaO4 中外延应力和剪切变形诱导的对齐自组织
DOI：
10.1021/acs.jpcc.1c09324
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Matsumoto Kaname
中科院分区：
文献类型：
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作者：
Horide Tomoya;Morishita Kazuki;Horibe Yoichi;Usuki Miya;Ishimaru Manabu;Matsumoto Kaname
尖晶石结构的ZnMnGaO4表现出以相分离和应变为主的自组织特性，实现了有序的纳米结构。为了控制薄膜的自组织，对脉冲激光沉积法制备的薄膜进行了后处理。适中的退火温度和较长的退火时间可以观察到有序的纳米棋盘和略粗的纳米片层结构，而较低的退火温度和较短的退火时间可以使薄膜形成孪晶结构。横截面观察表明，在表面附近有垂直排列的纳米结构(孪晶、纳米棋盘状或纳米片层)，在衬底附近有无缺陷的外延层。无论热处理条件如何，薄膜的面内晶格参数均与MgO[110]//ZMGO[101]上的相同，应力分析表明，由外延的外延应力和外延的剪应力决定了薄膜的垂直结构和孪晶宽度。薄膜的热力学稳定性和Mn、Ga的扩散基本上导致了自组织纳米结构的形成，外延应力和界面剪应力使薄膜中的自组织形成一致。因此，通过调节这些因素，可以在退火态的ZnMnGaO4薄膜中制备高度取向的自组织纳米结构。
Spinel ZnMnGaO4exhibits the characteristic self-organization dominated by phase separation and strain to realize an ordered nanostructure. To control the self-organization, ZnMnGaO4films fabricated using pulsed laser deposition were postannealed. While the ordered nano-checkerboard and the slightly coarse nanolamellar structures were observed for the moderate annealing temperature and the long annealing time, the twin structure was formed in the films annealed at the low temperature for the short annealing time. The cross-sectional observation showed the vertically aligned nanostructure near the surface (twin, nano-checkerboard, or nanolamellar) and the nondefective epitaxial layer near the substrate. The ZnMnGaO4films exhibited the same in-plane lattice parameter as that of MgO along the MgO[110]//ZMGO[101] regardless of annealing conditions, and the stress analysis indicates that the epitaxial stress at the epitaxial ZnMnGaO4/MgO and the shear stress at the epitaxial ZnMnGaO4/twinned ZnMnGaO4determined the vertical structure and the twin width. The thermodynamic stability and the Mn and Ga diffusion basically bring about the self-organized nanostructure formation as in bulk, and the epitaxial stress and the interface shear stress align the self-organization in the films. Thus, the highly aligned self-organized nanostructures can be fabricated in the annealed ZnMnGaO4films by tuning these factors.