Improvement in power durability of SAW filters

This paper describes the improvement in power durability of SAW filters in terms of filter designs and electrode materials. In this study, we used the previously reported ladder-type filter composed of one-port SAW resonators. For filter design, short aperture length and reduction of resonant resistance improved power durability. We clarified the frequency dependence of chip temperature and lifetime in a ladder-type filter. For electrode materials, Cu sandwiched film has high power durability. This is caused by stone-wall-like structure and alloy formation in intermediate layers. The optimum Cu quantity for multi-layered film was significant for high power durability