摘要 |
A branching filter that is capable of being reduced in size, particularly in height, has a configuration in which a transmitting filter chip and a receiving filter chip include a first piezoelectric substrate and a second piezoelectric substrate, respectively, and are spaced from each other. The transmitting filter chip includes a first insulating layer which extends over an IDT or which is disposed above the IDT. The receiving filter chip includes a first insulating layer which extends over an IDT or which is disposed above the IDT. The upper surfaces of the transmitting and receiving filter chips and are covered with a second insulating layer. External terminals arranged on the upper surface of a third insulating layer are electrically connected to the IDTs and through conductors and extending through the first insulating layers and the second insulating layer and the conductors, and include plating films.
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