Structure of TiAlN reactive sputtered coatings

Abstract

The Raman spectra, X-ray diffraction and hardness of the TiAlN films co-deposited on the steel substrates by reactive sputtering from Ti and Al targets in a mixture of N 2 + Ar gas with two magnetrons at room temperature have been studied. From Raman spectra it is found that the position of high-frequency bands in vibrational spectra was located at 700-730 cm -1 or in the region of 830 - 850 cm -1 depending on the deposition parameters whereas it is not exceed 630 cm -1 from TiAlN of NaCl structure. It is found the two-phase structure of coatings: a small quantity of NaCl-type structure of TiAlN (TiN) and the disordered structure of the chains of polyhedra [TiN x] with x = 5 and x = 4. The chains of polyhedra [TiN x] with x = 4 are mainly formed at large discharge power of Al(Ti) target or at small content of N 2 gas.