Modifying La-Mg-Ni alloy thin film microstructure using combinatorial methods

We have grown an array of discrete La-Mg-Ni thin films using combinatorial methods to modify the film microstructure by fine-tuning the composition. This method for creation of nanocrystalline/amorphous microstructure is significantly different from the usual energetic mechanical methods. Electron probe microanalysis measurements showed that our films have a wide range of compositions. The structures and surfaces of the different alloy films were studied using X-ray diffraction (XRD) and atomic force microscopy (AFM). XRD measurements revealed that the Mg-rich alloys consist of a main phase of (La, Mg)Ni3 with the hexagonal PuNi3-type structure and minor impurity phases of LaNi5. However, XRD of the La-rich alloys showed the formation of amorphous and nanocrystalline phases. AFM phase images showed different phases corresponding to different nucleation processes for the Mg-rich and La-rich alloys.