Abstract The orientation relationships and interfacial planes of the theta (θ)-Al2Cu/Cu and gamma2 (γ2)-Al4Cu9/Cu interfaces formed on the Cu (001) and (111) surfaces have been studied by transmission electron microscopy (TEM). Epitaxial thin Cu films are grown on the single-crystal NaCl surfaces and then Al is evaporated to form θ-Al2Cu and γ2-Al4Cu9. Results showed that the θ-Al2Cu first formed and then the γ2-Al4Cu9 formed. The orientation relationships at the Al/Cu interface were found: (1) [110]θ//[111]Cu (zone axis) and ( 1 ¯ 10 ) θ // ( 1 ¯ 1 ¯ 2 ) Cu on the (111)Cu surface, (2) the (110)γ2 surface is the interface with both the Cu (001) and (111) surfaces with a common orientation relationship of ( 1 ¯ 11 ) γ2// ( 1 1 ¯ 0 ) Cu, and (3) [110]θ//[110]γ2 (zone axis) and ( 1 ¯ 10 ) θ// ( 1 ¯ 1 2 ¯ ) γ2 on the (111)Cu surface. The θ/Cu, γ2/Cu, and γ2/θ interfaces were further analyzed. The γ2-Al4Cu9 phase has good orientation relationships to Cu and therefore low interfacial energies. In addition, the energy of formation of γ2-Al4Cu9 is about 1.2 times than that of eta (η)-AlCu. Therefore γ2-Al4Cu9 nucleates first after θ-Al2Cu.

中文翻译：

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θ-Al2Cu/Cu和γ2-Al4Cu9/Cu的取向关系和界面以及θ-Al2Cu和γ2-Al4Cu9在Cu/Al界面的形成顺序

摘要 通过透射电子显微镜(TEM) 研究了形成在Cu (001) 和(111) 表面上的θ (θ)-Al2Cu/Cu 和γ2 (γ2)-Al4Cu9/Cu 界面的取向关系和界面平面。在单晶 NaCl 表面上生长外延薄 Cu 膜，然后蒸发 Al 形成 θ-Al2Cu 和 γ2-Al4Cu9。结果表明，首先形成θ-Al2Cu，然后形成γ2-Al4Cu9。发现了 Al/Cu 界面处的取向关系：（1）[110]θ//[111]Cu（区轴）和 (1¯ 10 ) θ // ( 1¯ 1 ¯ 2 ) Cu on the (111 )Cu 表面， (2) (110)γ2 表面是与 Cu (001) 和 (111) 表面的界面，具有 ( 1 ¯ 11 ) γ2// ( 1 1 ¯ 0 ) Cu， (3) [110]θ//[110]γ2 (区轴) 和 (1¯ 10 ) θ// ( 1¯ 1 2 ¯ ) γ2 在 (111)Cu 表面。θ/Cu, γ2/Cu, 和 γ2/θ 界面进行了进一步分析。γ2-Al4Cu9 相与 Cu 具有良好的取向关系，因此界面能较低。此外，γ2-Al4Cu9 的生成能约为 eta (η)-AlCu 的 1.2 倍。因此γ2-Al4Cu9 在θ-Al2Cu 之后首先成核。