SURFACE ACOUSTIC WAVE FILTER INCLUDING WIRING PATTERN HAVING AT LEAST A PART FORMED ON INSULATION PATTERN, AND COMMUNICATION APPARATUS

摘要

PURPOSE: A surface acoustic wave filter and a communication apparatus are provided to reduce a parasitic capacitance between wiring patterns, and increase a signal suppression level outside a pass band. CONSTITUTION: A surface acoustic wave filter(200) comprises a piezoelectric substrate(100); an insulation pattern(2) formed on the piezoelectric substrate, wherein the insulation pattern has a dielectric constant smaller than that of the piezoelectric substrate; and a conductor pattern formed on at least one of the piezoelectric substrate and the insulation pattern. The conductor pattern has a certain part constituting IDTs(inter digital transducers), and a part of the other parts constituting wiring patterns. At least a part of one of the wiring patterns is formed on the insulation pattern, in the portion where wiring patterns having different potentials are opposed with each other.