In/Nb共掺杂TiO2薄膜结构特性的电子显微学研究

In/Nb共掺杂TiO₂薄膜结构特性的电子显微学研究

路  璐，李博宸，成绍鸫，米少波^*

（1.季华实验室，广东佛山528200；2. 材料科学与工程学院，西安交通大学，陕西西安710049）

摘  要   本文研究了In/Nb共掺杂TiO₂（TINO）薄膜在LaAlO₃（001）和m面a-Al₂O₃衬底上的生长行为和显微结构特征。研究发现TINO薄膜在LaAlO₃衬底上呈现锐钛矿结构（A-TINO），在m面a-Al₂O₃衬底上呈现金红石结构（R-TINO）。薄膜与衬底的晶体学取向关系分别为：(001)[100]A-TINO//(001)[100]LaAlO₃和(001)[100]R-TINO//(1 00)[0001]a-Al₂O₃。通过原子分辨率扫描透射高角环形暗场像技术确定了A-TINO/LaAlO3和R-TINO/a-Al2O3异质界面以及薄膜中孪晶和晶界的精细结构。本工作有助于理解TiO₂基薄膜的外延生长行为以及掺杂元素在材料中的偏聚特征。

关键词   二氧化钛；薄膜材料；掺杂；缺陷；界面结构

中图分类号：O484.1；O766+.1；O77+1    文献标识码：A   doi:10.3969/j.issn.1000-6281.2023.06.007

Microstructural characterization of (In/Nb) Co-doped TiO₂ thin films by advanced electron microscopy

LU Lu¹, LI Bo-Chen², CHENG Shao-Dong², MI Shao-Bo^1*

(1. Ji Hua Laboratory, Foshan Guangdong 528200; 2. School of Materials Science and Engineering, Xi'an Jiaotong University, Xi’an Shaanxi 710049，China)

Abstract   The growth and microstructures of In/Nb co-doped TiO₂(TINO) thin films prepared on LaAlO₃(001) and m-plane a-Al₂O₃ were investigated by advanced transmission electron microscopy (TEM). TINO thin films have an anatase structure (A-TINO) on LaAlO₃ and a rutile structure (R-TINO) on m-plane a-Al₂O₃. The film-substrate orientation relation was determined to be (001)[100]A-TINO//(001)[100]LaAlO₃ and (001)[100]R-TINO//(1 00)[0001] a-Al2O3. By high-angle annular dark-field imaging of scanning TEM, the structural details of A-TINO/LaAlO3 and R-TINO/a-Al2O3 heterointerface, twins, and grain boundaries were characterized at the atomic scale. Our findings provide a better understanding of the growth behavior of TiO2-based thin films on various substrates and cation segregation in the doped TiO2 materials.

Keywords   TiO₂; thin film; doping; defects; interface structure

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