ACOUSTIC WAVE DEVICE

• Main Author: SHIMONO OSAMU
• Format: Patent
• Language: English; Japanese
• Published: 12.07.2018
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

PROBLEM TO BE SOLVED: To provide an acoustic wave device including a dielectric film whose external surface has reduced irregularity, causing suppression of variation in the device's electric characteristic.SOLUTION: An acoustic wave device 100 comprises a piezoelectric substrate 1 having a main surface having thereon: a region in which a functional electrode F1 including an interdigital electrode 2 and reflectors 3, 4 and a functional electrode F2 including an interdigital electrode 7 and reflectors 8, 9 are formed, the region being referred to as a first region R1; and a region other than the first region R1, the region being referred to as a second region R2. On the second region R2, the acoustic wave device further comprises: metal members 5, 6 formed so as to be adjacent to the functional electrode F1; and metal members 10, 11 formed so as to be adjacent to the functional electrode F2. The metal members 5, 6, 10, 11 are connected to none of the functional electrodes F1, F2. A dielectric film 12 is formed on the main surface of the piezoelectric substrate 1 so as to coat all of the functional electrodes F1, F2 and metal members 5, 6, 10, 11.SELECTED DRAWING: Figure 1 【課題】誘電体膜の外表面の凹凸が低減され、電気的特性のばらつきが抑制された弾性波デバイスを提供する。【解決手段】弾性波デバイス１００は、圧電基板１の主面上において、櫛型電極２および反射器３、４を含む機能電極Ｆ１と、櫛型電極７および反射器８、９を含む機能電極Ｆ２とが形成されている領域を第１の領域Ｒ１とし、第１の領域Ｒ１以外の領域を第２の領域Ｒ２としたときに、第２の領域Ｒ２に機能電極Ｆ１と隣接して形成された金属部材５、６と、機能電極Ｆ２と隣接して形成された金属部材１０、１１とをさらに備えている。金属部材５、６、１０、１１は、機能電極Ｆ１、Ｆ２のいずれとも電気的に接続されていない。誘電体膜１２は、機能電極Ｆ１、Ｆ２と金属部材５、６、１０、１１とを共に被覆するように圧電基板１の主面上に形成されている。【選択図】図１