Correlation of Microstructural and Mechanical Properties of CVD Deposited TiAlN Coatings

摘要

Titanium aluminum nitride (TiAlN) thin films were synthesized with different N_2 flow rate on p-type Si (100) substrateand characterized by FESEM, AFM, XRD and nanoindentation to investigate the morphology, structural and mechanicalproperties. The FESEM images revealed non-uniform grain distribution with a higher degree of pores with the increasein N_2 flow rate. The XRD data indicated the presence of AlN, TiAlN, Al_2O_3 dominant phases at 33.07°, 55.5°, 61.79° and47.84°, 54.67° diffraction angles attributed to (100), (220) and (400), (112) diffraction plane, respectively. The AFM imagesrevealed the average roughness as 36.9 nm for 30 sccm N_2 flow rate. Furthermore, the mechanical properties such as H, E,plasticity index (H/E) and deformation to plastic resistance (H~3/E~2) of TiAlN thin film were found to be 21 GPa, 400 GPa,0.094 and 0.318 GPa, respectively, indicating higher resistance to crack with increasing N_2 flow rate.