Hi Sushant, I'm working on AlN thin film. AlN must be c-axis oriented perpendicular to substrate, if you want maximum electromechanical coupling. We deposit polycryistalline AlN by reactive DC magnetron sputtering of an Al target in gas mixture of N2 and Ar on Al electrode with these parameters: sputtering pressure: 0.66e-2 mbar substrate temperature: 140°C ratio N2 / N2 + Ar: 65% AlN is c-axis oriented perpendicular to substrate, and AlN is in tensile stress. Laurie