该文采用磁控溅射法在蓝宝石基片上制备出高择优取向的极薄氮化铝(AlN)压电薄膜。使用原子力显微镜(AFM)和X线衍射仪(XRD)分析了AlN压电薄膜的表面形貌和取向, 并用膜厚测试仪和应力测试仪检测了AlN压电薄膜的膜厚和应力。试验结果表明,制备的AlN压电薄膜择优取向(002)良好, 摇摆曲线半高宽达到3.21°, 均方根粗糙度为1.56 nm, 应力为-6.22 MPa。利用该文研究的AlN压电薄膜制作工艺研制的高频声体波延迟线工作频率达到24 GHz, 插入损耗为50.7 dB, 优于美国Teledyne公司的产品。

The ultra-thin aluminum nitride (AlN) films were deposited by the magnetron sputtering method on Al2O3 substrate. The surface morphology and preferential orientation were characterized by atom force microscope (AFM) and X-ray diffraction(XRD). The thickness and stress of AlN film were tested by membrane thickness tester and stress tester. The experimental results show that the film has a good preferential (002) orientation, and the rocking curve was 3.21°, the average root roughness was 1.56 nm and the stress was -6.22 MPa. Using the AlN piezoelectric film manufacturing process studied in this article, a high-frequency acoustic bulk wave delay line with a working frequency of 24 GHz and an insertion loss of 50.7 dB has been developed. The performance of the BAW delay line is better than that of Teledyne company in the United State.