Study of thermal stability and mechanical properties of amorphous Zr_(19)W_(18)N_(63) coatings deposited by DC/RF reactive magnetron sputtering

摘要

Thermal stability andmechanical properties of Zr-W-N films have been studied. Zr-W-N films of various structure have been deposited on Si substrates by DC/RF reactive magnetron sputtering at various substrate temperatures T_s (100°-600 °C) and at constant N2 partial pressure (0.27 Pa). For 100 °C ≤ T_s ≤ 300 °C, X-ray diffraction patterns show an amorphous structure of the films which is further confirmed by transmission electron microscopy measurements. For 400 °C ≤ T_s ≤ 600 °C, a crystalline fcc phasewith (111) and (200) orientation has been observed. Maximum wear resistance (H/Er ~ 0.22) and maximum resistance to fatigue fracture (H~3/E_r~2 ~ 1.1 GPa) have been obtained for the amorphous films deposited at T_s = 200 °C. Post annealing of films deposited at 200 °C has been carried out in air from 100° to 600 °C. Oxygen starts to be incorporated in the films at 300 °C annealing temperature (Tn) and its content increases with increasing T_n. No crystalline oxide phases are observed up to T_n = 600 °C. The hardness of the annealed films decreases with increasing oxygen incorporation.