用改进双延迟线法测量SAW相速度  

Determination of SAW Phase Velocity by Improved Dual-delay-line Method

作　　者：熊军[1] 公勋[1] 商晓莉[1] 王耀俊[1] 章德[1] 

机构地区：[1]南京大学电子科学与工程系,近代声学教育部重点实验室,江苏南京210093

出　　处：《压电与声光》2009年第2期161-163,共3页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(10404014)

摘　　要：双延迟线法是测量声表面波(SAW)速度的一种优秀方法,其样品制备工艺成熟,测量和数据处理简单。从原理上消除了换能器的影响,能达到很高精度。主要测量误差源有中心频率和距离的测量误差两个。对此提出了两项改进措施,即对幅频响应数据进行数字滤波后再做插值,以减小中心频率的测量误差;结合光学显微镜大视野和扫描电子显微镜(SEM)高精度的优点,提高距离测量精度。在128°Y-X铌酸锂基片上进行了实验,测量精度达到数米每秒。The dual-delay-line method is an excellent method for measuring SAW velocity. The technology for sampling preparation is mature and the measurement and data processing are simple. Because the influence of transducers is eliminated from its principle, high accuracy is possible. There are two sources of measurement error： determination of center frequency and measurement of the distance. There are two methods to solve these problems, that is, after digital filtering and then interpolation are held for Magnitude-Frequency data so as to reduce the measurement error of center frequency; both optical microscope and SEM are used to take advantages of large visual field and high accuracy in distance measurement. Experiments on 128° Y-X LiNbO3 substrate are carried out and the accuracy of several meters per second is obtained.

关 键 词：双延迟线 声表面波(SAW)相速度 测量误差 

分 类 号：O42[理学—声学] TN65[理学—物理]