Copper thin film of alternating textures

Abstract

It is common for thin films to have a predominant texture, but not alternating textures. In this letter, we report a copper film of alternating textures through self-organization. Using dc magnetron sputtering technique, we deposit copper films on a SiO₂/Si(111) substrate. A thin layer of copper of 〈111〉 texture is first developed, and another thin layer of 〈110〉 ensued. As deposition continues, a third layer of copper of 〈111〉 texture is formed on the top, leading to a sandwich copper thin film of alternating 〈111〉 and 〈110〉 textures. The film morphology is characterized with scanning electron microscopy and atomic force microscopy and the texture with x-ray diffraction. Based on anisotropic elastic analyses and molecular dynamics simulations, we propose a model of texture evolution during the formation of multilayers, attributing the texture evolution to the competition of surface and strain energies.