High frequency optoelectronic communication devices require increasingly high piezoelectric material properties,and aluminum nitride (AlN) thin films have attracted attention due to their excellent piezoelectric properties.The deposition process optimization of AlN thin film with high orientation and high-piezoelectric performance has become one of the bottleneck technologies for its application and expansion.Among many preparation process parameters,temperature is one of the key parameters affecting the lattice orientation of AlN thin films.In this paper,aluminum nitride thin films were deposited by magnetron sputtering system,and the effect of deposition temperature on AlN thin film crystal orientation and piezoelectric performance was discussed.X-ray diffraction (XRD) results show that (100) oriented AlN can be obtained under 250 ℃ deposited temperature,and (002) oriented AlN is preferred under 300 ℃;The piezoelectric test results show that piezoelectric constant d*₃₃ reaches its maximum value of 0.79 V under 250 ℃,exhibiting excellent piezoelectric characteristics.Based on atomic force microscopy (AFM) and effect of temperature on stability of valence bonds,the mechanism of temperature on its growth was explored.