SAW device with inclined reflectors and communication device using SAW device

摘要

A saw device comprises input/output interdigital transducer (IDT) electrodes(11,12) provided on piezoelectric substrates (10), a first reflector electrode (13) following the input IDT electrode (11), and a second reflector electrode (14) preceding the output IDT electrode (12). The device satisfies the following inequality (1) to provide preferable characteristics in a pass band: 2(&thgr;−5)≦tan^−1(D/L)≦2(&thgr;+5) where &thgr;: the inclination (in degree, except zero) of the first or second reflector electrode of the input and output IDT electrodes with respect to a plane perpendicular to the direction in which surface acoustic waves travel. D: the pitch (in micron) of the input and output IDT electrodes in the direction in which surface acoustic waves travel. L: the pitch (in micron) of the first and second reflector electrodes.