Elastic wave device

• Main Author: DAIMON KATSUYA
• Format: Patent
• Language: Chinese; English
• Published: 25.06.2024
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

The invention provides an elastic wave device capable of suppressing useless waves and reducing insertion loss in a band between a resonant frequency and an anti-resonant frequency. An elastic wave device (10) according to the present invention is provided with: a support member including a support substrate; a piezoelectric layer (14) that is provided on the support member, contains lithium niobate or lithium tantalate, and has a first main surface (14a) and a second main surface (14b) that face each other; an IDT electrode (11) provided on a first main surface (14a) of the piezoelectric layer (14) and having a pair of bus bars (a first bus bar (26), a second bus bar (27)) and a plurality of electrode fingers (a plurality of first electrode fingers (28), a plurality of second electrode fingers (29)); and at least one mass-added film disposed on the piezoelectric layer (14). An acoustic reflection portion is formed at a position overlapping at least a portion of the IDT electrode (11) in a plan view as viewed