Transparent Zr-Al-O oxide coatings with enhanced resistance to cracking

The article reports on structure, transparency and mechanical properties of Zr-Al-O oxide thin films with Zr/Al>1 produced by reactive DC pulse dual magnetron sputtering. Special attention is devoted to the formation of transparent Zr-Al-O oxide films in the transition mode of sputtering and their unique properties. It is shown that (i) the transparent Zr-Al-O films can be deposited in the transition mode of sputtering with a high deposition rate a _D achieving up to 80nm/min at relatively low value of the magnetron target power density W _t≈45 W/cm ², (ii) the Zr-Al-O films sputtered in the transition and oxides mode of sputtering are highly elastic and exhibit relatively high hardness (typically H≈18 to 19GPa), low effective Young's modulus E ^* satisfying the ratio H/E ^*>0.1 and high elastic recovery W _e up to 78%, and highly elastic Zr-Al-O oxide films with H/E ^*>0.1 exhibit an enhanced resistance to cracking.