SURFACE WAVE DEVICE, LATERAL WAVE TRANSDUCER AND LONGITUDINAL WAVE TRANSDUCER, AND MANUFACTURING METHOD FOR THEM

摘要

PROBLEM TO BE SOLVED: To obtain a surface wave device that has a small insertion loss, a large electromechanical coupling coefficient (k) and an excellent conversion efficiency. SOLUTION: This invention provides the surface wave device 1 where electrodes made of a low resistance ZnO film 13 formed by doping an impurity to ZnO whose specific resistivityρis 1Ω.cm or below are formed on a substrate 2, a piezoelectric film 14 whose specific resistivityρis 106Ω.cm or over and whose lattice constant is within±20% of that of the ZnO is formed on the electrodes, and interdigital electrodes 15 are formed on the piezoelectric film 14.