US 12,388,413 B2 · Acoustic wave device with enhanced quality factor and fabrication method thereof

Abstract

An acoustic wave device includes a piezoelectric substrate, a transducer, and a depression. The transducer is disposed on a surface of the piezoelectric substrate, and includes a first bus bar, a first electrode, a second bus bar, and a second electrode. The first bus bar and the second bus bar extend along a second direction. The first electrode has a first end and extends from the first bus bar along a first direction. The first electrode and the second electrode are spaced apart from each other, and a gap is formed between the first end of the first electrode and an edge of the second bus bar. The depression is formed in the piezoelectric substrate and is depressed from the surface of the piezoelectric substrate. The first end of the first electrode is continuously joined to a sidewall of the depression along a depth direction.

Claims20

Dependent claims

An acoustic wave device comprising:

a piezoelectric substrate having a first surface;
a transducer disposed on the first surface of the piezoelectric substrate, the transducer comprising:
a first bus bar extending along a second direction;
a first electrode having a first end, and extending from the first bus bar to the first end along a first direction;
a second bus bar extending along the second direction;
and
a second electrode having a second end and extending from the second bus bar to the second end along the first direction, wherein the second electrode and the first electrode is spaced apart in the second direction, and a first gap is formed between the first end of the first electrode and an edge of the second bus bar;
and
a first depression formed in the piezoelectric substrate and depressed from the first surface of the piezoelectric substrate, wherein the first depression has a first sidewall, and the first end of the first electrode is continuously joined to the first sidewall of the first depression in a depth direction.

6 more elements

A method of fabricating an acoustic wave device, the method comprising:

providing a piezoelectric substrate, the piezoelectric substrate having a first surface;
forming a conductive layer on the first surface;
patterning the conductive layer to form a patterned conductive layer, wherein the patterned conductive layer comprises:
a first bus bar extending along a second direction;
a first electrode having a first end and extending from the first bus bar to the first end along a first direction;
a second bus bar extending along the second direction;
and
a second electrode having a second end and extending from the second bus bar to the second end along the first direction, wherein the second electrode and the first electrode is spaced apart in the second direction, and a first gap is formed between the first end of the first electrode and an edge of the second bus bar;
and
forming a first depression in the piezoelectric substrate, wherein the first depression is depressed from the first surface of the piezoelectric substrate, the first depression has a first sidewall, and the first end of the first electrode is continuously joined to the first sidewall of the first depression in a depth direction.

7 more elements

Dependencies are inferred from the claim text.

Acoustic wave device with enhanced quality factor and fabrication method thereof

Life of this patent

Acoustic wave device with enhanced quality factor and fabrication method thereof

Life of this patent

Abstract

Claims20