LaAlO3基体上 CaBaCo2 O5＋δ多晶薄膜的微观结构以及生长方式

摘要

CaBaCo2 O 5 +δ thin films were deposited on (001 )LaAlO 3 substrates by pulsed laser deposition.The microstructures of the film and substrate were studied by X-ray diffraction (XRD)and of transmission electron microscopy (TEM).Results show that (1 )dislocations and twins appear in the LaAlO 3 substrates,and the (100)wedge-shaped twin was the main type;(2)CaBaCo2 O 5 +δ thin film was polycrystalline in nature,and the initial grain structure with a grain size of about 5-8 nm during growth was kept at the bottom of the film.While the grain size at the top of the film was larger,about 1 1-1 6 nm.Based on the observation results,a growth mechanism of the film was proposed.Possible processes to improve the film quality have also been discussed.%采用脉冲激光沉积方法,在(001)LaAlO 3上沉积 CaBaCo2 O 5＋δ多晶薄膜,用 X 射线衍射(XRD)和透射电子显微镜(TEM)对基体和薄膜的微观结构进行观察,并探讨了薄膜的生长机制以及改善薄膜质量的可能工艺.结果表明,(1)LaAlO 3基体中存在位错、孪晶等缺陷,且孪晶类型以(100)楔形孪晶为主；(2)CaBaCo2 O 5＋δ薄膜为多晶薄膜,薄膜底部保留了薄膜生长过程中的初始晶粒结构,晶粒大小约5~8 nm,厚度约为5~7 nm.薄膜顶层的晶粒较大,约为11~16 nm.