La_(0.9)Sr_(0.1)MnO_3/Si体系界面的电子显微学研究

Transmission electron microscopy study of the La_(0.9)Sr_(0.1)MnO_3/Si interface

本文利用透射电子显微术,研究了通过激光分子束外延方法在Si基体上生长的La0.9Sr0.1MnO3功能薄膜的显微结构特征及界面处的微区成分分布规律。结果表明,在Si基体上生长的La0.9Sr0.1MnO3薄膜由单相多晶体构成。这些多晶体颗粒以柱状结构生长,柱状晶垂直于界面并一直贯穿整个LSMO薄膜。La0.9Sr0.1MnO3薄膜具有正交点阵结构,其颗粒大小为10 nm^20 nm。在LSMO/Si的界面处发现了由化学反应引起的两个纳米尺度的非晶层。

Thin film of La0.9Sr0.1MnO3/Si prepared by laser molecular beam epitaxy on Si substrate was characterized by means of transmission electron microscopy. The La0.9Sr0.1MnO3 film has an orthorhombic structure and it was polycrystallined with grain size of 10 nm - 20 nm. The grains of La0.9Sr0.1MnO3 displayed a columnar growth normal to the interface. Between the La0.9Sr0.1MnO3 film and Si substrate, two amorphous layers with nanometer dimensions were identified. The formation mechanism of these amorphous layers is proposed on the basis of EDS composition scanning.