Speakers
Description
The chromium aluminium nitride (CrAlN) thin films were deposited on Si by using reactive DC unbalanced magnetron sputtering method from alloy target and then annealed in air at different temperatures for 1 hr. The effect of annealing temperature on the structure, chemical composition, morphology, and hardness of the films was characterized by XRD, EDS, FE-SEM, and Nanoindentation, respectively. The as-deposited thin films were solid solutions of (Cr,Al)N with (111), (200), and (220) planes. The film composes of chromium, aluminium, and nitrogen in different ratios, with slight oxygen. The lattice constant was in the range of 4.104 – 4.145 Å. The average crystal size was increased from 17.2 to 22.4 nm with an increase in annealing temperature. The result from the FE-SEM technique was revealed that the as-deposited films annealed at the low temperature showed the dense morphology, and turned to be the compact columnar structure at the high temperature of more than 700 OC. However, when the annealing temperature was increased up to 900 OC, a slight increase in oxygen content in the films. The film’s hardness decreased from 67.3 GPa to 50.1 GPa with increasing the annealing temperature. In addition, the crystal structure or the oxides layer were not observed, showed that alloyed aluminium in the film can improve the oxidation resistance up to 900 OC.
