Surface acoustic wave (saw) filter having temperature compensation layer

Abstract

Disclosed is a surface acoustic wave (SAW) filter having a temperature compensation layer. The SAW filter includes: a series resonator group having a plurality of series-type SAW resonators connected in series; and a parallel resonator group having a plurality of parallel-type SAW resonators connected in parallel. Each of the series-type SAW resonators and the parallel-type SAW resonators comprises a piezoelectric substrate, an interdigital transducer (IDT) electrode formed on the piezoelectric substrate, and a temperature compensation layer covering the IDT electrode. At least one series-type SAW resonator among the series-type SAW resonators has a temperature compensation layer having a layer thickness different from layer thicknesses of temperature compensation layers of other series-type SAW resonators, or at least one parallel-type SAW resonator among the parallel-type SAW resonators has a temperature compensation layer having a layer thickness different from layer thicknesses of temperature compensation layers of other parallel-type SAW resonators.

Dependencies are inferred from the claim text.