Multilayer Composite Ceramic-metal Thin Film: Structural and Mechanical Properties

Multilayer coatings with combination (10 BL, 20 BL and 30 BL) of transition-metal nitride (tungsten nitride, W2N) and ductile interlayers (Ti, Ni) were deposited by reactive DC magnetron sputtering technique on silicon substrates. Structural and mechanical properties of the deposited samples were analyzed by grazing incidence X-ray diffraction (GIXRD), field emission scanning electron microscope (FESEM), energy dispersive X- ray analysis (EDX) and nanoindentation tests. GIXRD result confirms the presence of cubic W2N phase. FESEM image shows periodic arrangement of W2N and (Ti, Ni). Mechanical parameters like hardness, elastic modulus and resistance to plastic deformation were calculated. The effect of different factors e.g. ceramic/ metal ratio, interlayer material and interface on mechanical properties were discussed. These results indicate that these factors play a dominant role in defining mechanical properties. The best mechanical properties were observed for 20 BL in comparison with 10 BL and 30 BL coating and has been attributed to higher ceramic to metal thickness ratio.

How Moorfield products helped:

MiniLab ES60A

Experimental

W2N/Ti and W2N/Ni multilayers were deposited on single crystalline Silicon (100) substrates in ultra-high vacuum using DC sputtering unit (Minilab Deposition System) with Model ES60A supplied by Moorfield, UK. Sputtering was carried out in grounded substrate bias condition. Prior to deposition substrates were cleaned properly with soap solution and then ultra-sonicated in alcohol and distilled water for 10 min each. The sputtering chamber is equipped with four targets of 50 mm diameter each.

Open Access publication details: