US 11,444,596 B2 · Acoustic wave device

Abstract

An acoustic wave device includes a piezoelectric substrate, an IDT electrode and an electrode pad provided on a front surface of the piezoelectric substrate, a support layer provided on the front surface so as to surround the IDT electrode, a first cover layer and a second cover layer provided on the support layer such that the first cover layer, the second cover layer, the support layer, and the piezoelectric substrate seal the IDT electrode in a hollow space, a UBM portion joined to the electrode pad, and a bump joined to the UBM portion. A joint surface of the UBM portion at which the UBM portion is joined to the bump has a spherical shape or substantially spherical shape that is convex towards the bump side.

Claims17

Dependent claims

An acoustic wave device comprising:

a piezoelectric substrate;
a functional electrode provided on a front surface of the piezoelectric substrate;
an electrode pad provided on the front surface of the piezoelectric substrate;
a support provided on the front surface of the piezoelectric substrate and surrounding the functional electrode;
a cover provided on the support such that the cover, the support, and the piezoelectric substrate seal the functional electrode in a hollow space;
a via conductor joined to the electrode pad;
and
a bump joined to the via conductor;
wherein
a joint surface of the via conductor at which the via conductor is joined to the bump has a curved shape that is convex towards a bump side;
the via conductor penetrates through the piezoelectric substrate;
and
the bump projects from a rear surface of the piezoelectric substrate.

10 more elements

Dependencies are inferred from the claim text.

Acoustic wave device

Life of this patent

Acoustic wave device

Life of this patent

Abstract

Claims17