不同调制结构Ni/Al型纳米多层膜的非对称扩散及界面应力演化行为

为了研究分析室温下溅射沉积的金属异质结界面演化的尺度依赖性,制备了不同调制周期和Ni:Al调制比等特征结构的Ni/Al型金属纳米多层膜。结合X射线衍射,多光束光学应力传感器(MOSS)实时薄膜曲率测量,研究了应力演化行为,并在此基础上分析推测纳米多层膜在生长过程中的界面特性。实验结果表明,由于各亚层内各向异性纳米晶结构,多层膜界面具有不对称性,这是由于界面处Ni原子向Al晶格内的不对称扩散行为所致。特别地,当此类型多层膜具备最小调制周期和最低Ni:Al调制比这两个特征参量时,上述不对称扩散行为由于界面累积效应变得更为加剧。

Asymmetric intermixing and the stress buildup in Ni/Al-typed nanomultilayer with different characteristic scales

In order to detect scale-dependent interfacial evolution of metallic heterostructure during the deposition at room temperature, Ni/Al-typed nanomultilayers were prepared as a function of the periodicity and Ni:Al modulated ratio. Combined with X-ray diffraction, real-time plate curvature measurements by multi-beam optical stress sensor (MOSS) were employed to study the stress buildup so as to speculate interfacial characteristics during the growth process. Experimental results show that, with anisotropic nanocrystalline structure within the sub-layers, the multilayers possess of asymmetrical interfaces, which is a result of dissymmetrical diffusion of Ni to Al lattice near the interface. Specially, for the smallest periodicity with the lowest Ni:Al ratio, above asymmetric intermixing behaviors turns to be aggravated by a promotion effect.