US 2019/0103853 A1 · BULK ACOUSTIC WAVE RESONATOR WITH PIEZOELECTRIC LAYER COMPRISING LITHIUM NIOBATE OR LITHIUM TANTALATE

Abstract

A bulk acoustic wave (BAW) resonator includes a substrate defining a cavity, a bottom electrode disposed over the substrate and the cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer. The piezoelectric layer includes polycrystalline lithium niobate (LN) material or polycrystalline lithium tantalite (LT) material. The BAW resonator may further include an encapsulant layer formed on side and top surfaces of the piezoelectric layer. The encapsulant layer is configured to protect the LN material or the LT material of the piezoelectric layer from a release solvent previously applied to sacrificial material within the cavity in the substrate.

Claims20

Dependent claims

A bulk acoustic wave (BAW) resonator comprising:

a substrate;
an acoustic reflecting feature on or in the substrate;
a bottom electrode disposed over the acoustic reflecting feature;
a piezoelectric layer disposed over the bottom electrode, the piezoelectric layer comprising one of polycrystalline lithium niobate (LN) material or polycrystalline lithium tantalate (LT) material;
an encapsulant layer formed over side and top surfaces of the piezoelectric layer, the encapsulant layer and the bottom electrode encapsulating the piezoelectric layer;
and
a top electrode disposed over the piezoelectric layer and the encapsulant layer.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/190,701Filed 14 Nov 2018

Priority

26 Jan 2016

Published

4 Apr 2019

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

H03H 9/175
Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume: acoustic mirrors
H03H 3/04
For the manufacture of piezoelectric or electrostrictive resonators or networks: for obtaining desired frequency or temperature coefficient
H03H 9/02118
Means for compensation or elimination of undesirable effects: of lateral leakage between adjacent resonators
H03H 9/173
Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume: air-gaps

Bulk acoustic wave resonator with piezoelectric layer comprising lithium niobate or lithium tantalate

Life of this patent

Bulk acoustic wave resonator with piezoelectric layer comprising lithium niobate or lithium tantalate

Life of this patent

Abstract

Claims20