Fabrication of Well-Aligned Al Nanowire Array Embedded in Si Matrix Using Limited Spinodal Decompositon

Abstract

The morphology of a phase-separated binary film during spinodal decomposition, whose evolution is limited on the growth surface, is studied. The temporal evolution of the Cahn–Hilliard equation without the elastic energy term under frozen bulk approximation is solved to investigate the possibility of well-aligned nanostructures. The model simulation showed that the well-aligned phase pattern on the top surface can be formed when surface diffusion length was optimized and film thickness was larger than a certain value. These simulation results highly agree with the experimental observation of phase-separated Al–Si films. An additional simulation study indicated that well-aligned nanowires can be prepared from the initial growth stage when an initial phase pattern given on the substrate matched the periodicity of the phase pattern of deposited films.