Synthesis and structural properties of DC sputtered AlN thin films on different substrates

Aluminum Nitride thin films were prepared over different substrates using DC sputtering at room temperature. The prepared films were mostly c-axis oriented on Al substrates. Poor crystalline were recorded for both glass and Si substrates. Cu substrates supported the growth of cubic (2 0 0) AlN. Annealing process showed noticeable effect on c-axis AlN prepared over Al substrates. The observed crystallite sizes were between 9 nm and 79 nm. The applied stress during the growth were tensile nature and showed high value for (1 1 0) phase on Al substrates. The structural parameters such as dislocation density, micro strain etc., were dependent not only the orientation of AlN crystals but also the substrates used. Annealing process showed noticeable reduction on residual stress and micro strain and improvement on crystallite growth as well as the dislocation density.