Printed circuit board and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-10193055-B2
Application number	US-201514954284-A
Country	US
Kind code	B2
Filing date	Nov 30, 2015
Priority date	Dec 2, 2014
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

A printed circuit board includes: insulating layers and wiring layers arranged in stacked configuration; a cavity disposed in a first insulating layer among the insulating layers; a piezoelectric substrate disposed in the cavity; an electrode disposed on the piezoelectric substrate and configured to convert an electrical signal into an elastic wave or to convert an elastic wave into an electrical signal; and a sealing part disposed on the piezoelectric substrate, the sealing part enclosing the electrode and forming an air gap around the electrode.

First claim

What is claimed is:

1. A printed circuit board comprising:
a first insulating layer;
a first wiring layer disposed on an upper surface of the first insulating layer;
a second insulating layer disposed above the first insulating layer, and on the first wiring layer;
a second wiring layer disposed on an upper surface of the second insulating layer;
a cavity disposed in the first insulating layer;
a piezoelectric substrate disposed in the cavity;
an electrode disposed on the piezoelectric substrate and configured to convert an electrical signal into an elastic wave or to convert an elastic wave into an electrical signal;
a first via extending through the second insulating layer and into the first insulating layer, and electrically connecting the electrode to the second wiring layer;
a second via extending through the second insulating layer and electrically connecting the first wiring layer to the second wiring layer; and
a sealing part disposed on the piezoelectric substrate, the sealing part enclosing the electrode and forming an air gap around the electrode.

2. The printed circuit board of claim 1 , wherein the sealing part comprises a non-conductive material.

3. The printed circuit board of claim 1 , wherein the air gap is filled with an electrode corrosion inhibitor.

4. The printed circuit board of claim 1 , wherein the electrode includes an interdigital transducer (IDT).

5. The printed circuit board of claim 1 , wherein the first insulating layer is a core layer.

6. A printed circuit board comprising:
a core layer comprising a cavity;
an elastic wave element disposed in the cavity, and comprising:
a piezoelectric substrate;
an IDT disposed on the piezoelectric substrate, and
a sealing part disposed on the piezoelectric substrate, the sealing part enclosing the IDT and forming an air gap around the IDT;

a first wiring layer disposed on an upper surface of the core layer;
an insulating layer disposed above the core layer and on the first wiring layer;
a second wiring layer disposed on an upper surface of the second insulating layer;
a first via extending through the insulating layer and into the core layer, and electrically connecting the IDT to the second wiring layer; and
a second via penetrating through the insulating layer and electrically connecting the first wiring layer to the second wiring layer.

7. The printed circuit board of claim 6 , wherein the sealing part comprises a non-conductive material.

8. The printed circuit board of claim 6 , wherein the air gap is filled with an electrode corrosion inhibitor.

9. A method of manufacturing a printed circuit board, the method comprising:
forming a cavity in a core layer;
forming a piezoelectric substrate in the cavity;
forming an electrode on the piezoelectric substrate, the electrode being configured to convert an electrical signal into an elastic wave or an elastic wave into an electrical signal;
forming a sealing part on the piezoelectric substrate to enclose the electrode and form an air gap around the electrode;
forming a first wiring layer on an upper surface of the core layer;
forming an insulating layer above the core layer and on the first wiring layer;
forming a second wiring layer on an upper surface of the insulating layer;
forming a first via in the insulating layer and the core layer, the first via electrically connecting the electrode to the second wiring layer; and
forming a second via in the insulating layer, the second via electrically connecting the first wiring layer to the second wiring layer.

10. The method of claim 9 , wherein the electrode comprises an IDT.

11. The method of claim 9 , wherein the sealing part comprises a non-conductive material.

12. The method of claim 9 , further comprising adjusting a thickness of the piezoelectric substrate or a thickness of the sealing part to control a size of the air gap.

13. The method of claim 9 , further comprising filling the air gap with an electrode corrosion inhibitor.

14. The method of claim 9 , wherein the forming of the piezoelectric substrate comprises injecting a piezoelectric material into the cavity and hardening the piezoelectric material.

15. The method of claim 9 , wherein the forming of the cavity comprises forming the cavity using a laser beam, a punch, or a blade.

16. A method of manufacturing a printed circuit board, the method comprising:
forming a cavity in a core layer;
forming a piezoelectric substrate in the cavity by injecting a piezoelectric material into the cavity and hardening the piezoelectric material;
forming an electrode on the piezoelectric substrate, the electrode being configured to convert an electrical signal into an elastic wave or an elastic wave into an electrical signal;
forming a sealing part on the piezoelectric substrate to enclose the electrode and form an air gap around the electrode;
forming insulating layers above and below the core layer; and
forming wiring layers on the insulating layers.

17. A method of manufacturing a printed circuit board, the method comprising:
forming a cavity in a core layer using a laser beam, a punch, or a blade;
forming a piezoelectric substrate in the cavity;
forming an electrode on the piezoelectric substrate, the electrode being configured to convert an electrical signal into an elastic wave or an elastic wave into an electrical signal;
forming a sealing part on the piezoelectric substrate to enclose the electrode and form an air gap around the electrode;
forming insulating layers above and below the core layer; and
forming wiring layers on the insulating layers.

Assignees

• Samsung Electro Mech

Inventors

• Hwang Mi Ran
• Kim Se Jong

Classifications

• H05K3/4697

  having cavities, e.g. for mounting components (H05K3/4691 takes precedence) · CPC title

• H05K3/46 Primary

  Manufacturing multilayer circuits · CPC title

• H05K1/16

  incorporating printed electric components, e.g. printed resistors, capacitors or inductors · CPC title

• H05K1/18

  structurally associated with non-printed electric components (H05K1/16 takes precedence) · CPC title

• H05K3/4602

  characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated · CPC title