Patent ID: 11870423
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A filter device, comprising:
a substrate;
a lithium niobate (LN) plate having front and back surfaces, the back surface attached to the substrate except for portions of the LN plate forming a plurality of diaphragms that span respective cavities in the substrate;
a conductor pattern formed on the front surface, the conductor pattern including a plurality of interdigital transducers (IDTs) of a respective plurality of resonators including a shunt resonator and a series resonator, interleaved IDT fingers of each of the plurality of IDTs disposed on respective diaphragms;
a first dielectric layer having a thickness tds deposited on one of the front surface and the back surface of the diaphragm of the series resonator; and
a second dielectric layer having a thickness tdp deposited one of the front surface and the back surface of the diaphragm of the shunt resonator, wherein
tdp is greater than tds, and
Euler angles of the LN plate are [0°, β, 0°], where 20°≤β≤25°.