Ceramics-Silikáty

AlN films, which are widely used in microelectronic devices, have excellent optical, thermal, acoustic and piezoelectric properties. However, AlN films easily fail due to the poor bonding force between the film and the substrates under loads, which greatly limits the wide application of AlN films in microelectronic fields. In this work, AlN films were deposited on an Si (100) substrate by the radio frequency (RF) magnetron sputtering technology. The temperature and bias voltage effects on the microstructure and mechanical properties of the films were studied. The results show that, with the increase in the temperature and bias voltage, the (100) preferred orientation of AlN films gradually weakens, and the (002) orientation gradually increases. The columnar crystal structures showed no obvious change with the increasing temperature, but gradually coarsen with the increasing bias voltage. Moreover, with the increase in the temperature and bias voltage, the residual stress significantly reduced, the binding force between the films and the substrates was improved, and the binding force was about 13.9 N at 400 °C and 125 V. The results show that optimising the temperature and bias voltage can help in obtaining AlN films with a specific preferred orientation and improve the binding force of AlN films.