Preparation and characterization of Er-doped AlN films by RF magnetron sputtering

Er-doped AlN thin films were deposited by RF magnetron sputtering on (0001) sapphire substrates under different temperature. We systematically investigate the influence of substrate temperature on the crystalline structure and the piezoelectric properties of the films. Consequently, the XRD intensity of (0 0 2) oriented peak first increases and then decreases with increasing substrate temperature, reaching a maximum value and a highly c-axis columnar crystal structure at 200 °C. The piezoelectric constant d33 indicates a maximum value of 9.41 pm/V at substrate temperature of 200 °C.Due to Er doping in AlN films, an improvement in their crystalline structures and piezoelectric properties is noticed.