Effect of Substrate-Target Distance on the Structure of TiCrN Films Deposited from Mosaic Target by Reactive DC Magnetron Sputtering

Abstract

Titanium chromium nitride (TiCrN) thin films were deposited on Si substrates by reactive DC unbalanced magnetron sputtering from the Ti-Cr mosaic target. The effect of substrate-to-target distances (dst) on the structure of TiCrN thin films were investigated. The crystal structure, microstructure, thickness, roughness and chemical composition were characterized by glancing angle X-ray diffraction (GAXRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDS) technique, respectively. The results showed that, all the as-deposited films were formed as a (Ti,Cr)N solid solution. The as-deposited films exhibited a nanostructure with a crystal size less than 65 nm. The crystal size of all plane were in the range of 36.3 – 65.7 nm. The lattice constants were in the range of 4.169 Å to 4.229 Å. The thickness and roughness decrease from 500 nm to292 nm and 3.6 nm to 2.2 nm, respectively, with increasing the substrate-to-target distance. The chemical composition, Ti, Cr and N contents, of the as-deposited films were varied with the substrate-to-target distance. The as-deposited films showed compact columnar and dense morphology as a result of increasing the substrate-to-target distance.