Formation of Ti-N thin films prepared by dynamic ion mixing technique and their mechanical properties

摘要

Ti-N thin films were formed on unheated Si(100) substrate with evaporation of Ti by electron beam and simultaneous bombardment of N ion beam in the range of 1~40 keV. The influence of N ion acceleration energies and the content ratios (N/Ti) onmicrostructures and phases was investigated by x-ray diffraction (XRD), Auger electron spectroscopy (AES) and transmission electron microscopy (TEM). The XRD spectra revealed the formation regions of the single phases and the mixture phases furα-Ti, thestoichometric compounds TiN and Ti{sub}2N at the various ion acceleration energies. The mechanical properties such as hardness, elastic modulus, adhesive strength and friction coefficient were also investigated. Nano-indentation studies showed that thehardness and the elastic moduli for each phase increased with increasing mixing layer thickness related to the ion acceleration energy. The single phase TIN and Ti{sub}2N films prepared at higher ion energy showed the excellent mechanical properties inthe hardness and adhesive strength. Relationship between other mechanical properties of the obtained films and their phases also discussed.