US Patent Application 18194256. TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR WITH THICK DIELECTRIC LAYER FOR IMPROVED COUPLING simplified abstract

TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR WITH THICK DIELECTRIC LAYER FOR IMPROVED COUPLING

Organization Name

Murata Manufacturing Co., Ltd.

Inventor(s)

Ventsislav Yantchev of Sofia (BG)

Sean Mchugh of Santa Barbara CA (US)

Bryant Garcia of Mississaugna (CA)

Patrick Turner of Portola Valley CA (US)

John P. Koulakis of Los Angeles CA (US)

TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR WITH THICK DIELECTRIC LAYER FOR IMPROVED COUPLING - A simplified explanation of the abstract

• This abstract for appeared for US patent application number 18194256 Titled 'TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR WITH THICK DIELECTRIC LAYER FOR IMPROVED COUPLING'

Simplified Explanation

The abstract describes a device called a bulk acoustic resonator. It consists of a substrate, a piezoelectric plate, and an interdigital transducer (IDT) on the front surface of the plate. The IDT is designed to generate a specific type of acoustic wave within the plate. The device also includes a half-lambda dielectric layer on either the front or back surface of the plate. The thickness of this layer is related to the wavelength of a specific type of acoustic wave resonance within the layer. Additionally, an acoustic Bragg reflector is placed between the substrate and the back surface of the plate. This reflector is designed to reflect the primary acoustic wave. The top layer of the reflector makes contact with either the piezoelectric plate or the half-lambda dielectric layer.

Original Abstract Submitted

A bulk acoustic resonator that includes a substrate, a piezoelectric plate, and an interdigital transducer (IDT) formed on the front surface of the piezoelectric plate. The IDT is configured to excite a primary shear acoustic mode within the piezoelectric plate. Also included is a half-lambda dielectric layer on at least one of the front surface or the back surface of the piezoelectric plate, where a thickness of the half-lambda dielectric layer is related to a wavelength of a fundamental shear bulk acoustic wave resonance in the half-lambda dielectric layer. The device further includes an acoustic Bragg reflector sandwiched between the surface of the substrate and the back surface of the piezoelectric plate, the acoustic Bragg reflector configured to reflect the primary acoustic mode. A top layer of the alternating layers of the acoustic Bragg reflector contacts the piezoelectric plate or the half-lambda dielectric layer.