Characterization and Piezoelectric Properties of Reactively Sputtered ( S c, A l) N Thin Films on Diamond Structure

Highly oriented wurtzite ( S c, A l) N films were deposited on a diamond/silicon by a co‐sputtering system. The results showed that the formation of S c x A l 1− x N alloys causes a lattice distortion during the phase transition, and this intermediate phase induces a large piezoelectric response. When the scandium concentration increased up to the solution limit of scandium in aluminum nitride (measured data are about 12 at.%), the piezoelectric coefficient of ( S c, A l) N film is four times larger than pure A l N layer. After annealing process, the d 33 value of ( S c, A l) N can be increased to a maximum of 20.073 p C / N .