Preparation And Properties Of TiN/AlN Thin Films Deposited By Magnetron Reactive Sputtering

Raising in the life time of cutting tools, bearings, moulds, etc. is very important for industrial applications, so in recent years there has been an increasing interest in materials with good properties, i.e. low friction coefficient, high hardness and corrosion resistance and oxidation resistance. Metal carbides and nitrides are commonly used for hard coating materials. Transition metal nitrides, especially TiN, are used as wear protective coatings for tools, but the function of single layer film has been already unable to satisfy the increasingly demanding requirements of applications. In this case, the bilayers or multilayer film coatings which have the higher hardness, corrosion resistance and oxidation resistance began to be widely used.In this work, TiN and A1N single layer and TiN/AIN bilayers were prepared by DC magnetron reactive sputtering on p-type Si (111) substrates, and their structure and properties were studied.In the first part of this dissertation, the influence of process parameters, such as sputtering pressure, sputtering current, substrate temperature, on the structure and properties of TiN thin films were investigated. TiN thin films with the best properties, that is, good crystallization, smooth and uniform surface and smaller surface roughness, were deposited by optimized technological parameters (sputtering current 0.45A, substrate temperature 480℃, sputtering pressure 0.6Pa).In the second part of this dissertation, the influence of sputtering pressure on the structure and properties of A1N thin films were studied. When the substrate temperature is 480℃, sputtering current is 0.4A, the A1/N2 gas flow ratio isl:3, A1N thin films with best quality were doposited at. sputtering pressure 0.6Pa.In the third part of this dissertation, TiN/AIN bilayer were prepared and studied. The diffraction peaks in XRD pattern of bilayer can be identified in single layer film. The energy gap of the A1N thin film is 5.83eV characterized by reflection spectra measurements. It was shown that TiN/AIN bilayer have better anti-oxidize and anti-eorrosive properties than single-layer TiN film via oxidation and eorrosion experiments.