Piezoelectric microspeaker and method of fabricating the same

• US 8,549,715 B2
• Filed: 04/23/2009
• Issued: 10/08/2013
• Est. Priority Date: 09/22/2008
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Dong-kyun, Chung, Seok-whan, Jeong, Byung-gil
• Primary Examiner(s): ANGWIN, DAVID PATRICK
• Application Number:
  US12/428,502
• Publication Number:
  US 20100072860A1
• Time in Patent Office: 1,629 Days
• Field of Search: 29/253.5, 298/901, 257/254, 310/311, 310/316.01, 310/317, 181/158, 347/68
• US Class Current: 29/25.35
• CPC Class Codes: H04R 17/005 using a piezoelectric polymer
• CPC Class Codes: H04R 2201/003 Mems transducers or their use of the electrostatic type H04R19/005
• CPC Class Codes: H04R 31/00 Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182
• CPC Class Codes: H10N 30/074 by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
• CPC Class Codes: H10N 30/082 by etching, e.g. lithography
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49401 Fluid pattern dispersing device making, e.g., ink jet

Abstract

A piezoelectric microspeaker fabricated by a method including: forming a lower drive unit by forming a first drive electrode by depositing and etching a first thin conductive layer on a substrate, forming a first piezoelectric plate by depositing and etching a first piezoelectric layer on the first drive electrode, and forming a first common electrode by depositing and etching a second conductive layer on the first piezoelectric plate; after forming the lower drive unit, forming a diaphragm by depositing a non-conductive layer on the first common electrode; and forming an upper drive unit by forming a second common electrode by depositing and etching a third conductive layer on the diaphragm, forming a second piezoelectric plate by depositing and etching a second piezoelectric layer on the second common electrode, and forming a second drive electrode by depositing and etching a fourth conductive layer on the second piezoelectric plate.

Claims

1. A piezoelectric microspeaker fabricated according to a method comprising:

forming a lower drive unit by;

forming a first drive electrode by depositing a first thin conductive layer on a substrate and etching the first conductive layer,

forming a first piezoelectric plate by depositing a first piezoelectric layer on the first drive electrode and etching the first piezoelectric layer, and

forming a first common electrode by depositing a second conductive layer on the first piezoelectric plate and etching the second conductive layer;

after the forming the lower drive unit, forming a diaphragm by depositing a non-conductive layer on the first common electrode; and

forming an upper drive unit by;

forming a second common electrode by depositing a third conductive layer on the diaphragm and etching the third conductive layer,

forming a second piezoelectric plate by depositing a second piezoelectric layer on the second common electrode and etching the second piezoelectric layer, and

forming a second drive electrode by depositing a fourth conductive layer on the second piezoelectric plate and etching the fourth conductive layer.

3. The piezoelectric microspeaker of claim 1, wherein the non-conductive layer comprises a polymer.

4. The piezoelectric microspeaker of claim 1, wherein a central region of the diaphragm protrudes in accordance with a shape of the lower drive unit, and wherein an edge region of the diaphragm and the lower drive unit are substantially co-planar.

5. The piezoelectric microspeaker of claim 1, wherein the method further comprises:

prior to the forming the lower drive unit, etching a part of the substrate to form a cavity, wherein the lower drive unit is formed substantially within the cavity.

6. The piezoelectric microspeaker of claim 5, wherein the diaphragm is substantially planar.

2. A piezoelectric microspeaker fabricated according to a method comprising:

forming a lower drive unit by depositing a first conductive layer on a substrate, etching the first conductive layer, depositing a first piezoelectric layer on the first conductive layer, and etching the first piezoelectric layer;

after the forming the lower drive unit, forming a diaphragm by depositing a second conductive layer on the lower drive unit and etching the second conductive layer; and

forming an upper drive unit by depositing a second piezoelectric layer on the diaphragm, etching the second piezoelectric layer, depositing a third conductive layer on the second piezoelectric layer, and etching the third conductive layer.

7. The piezoelectric microspeaker of claim 2, wherein a central region of the diaphragm protrudes in accordance with a shape of the lower drive unit, and

wherein an edge region of the diaphragm and the lower drive unit are substantially co-planar.

8. The piezoelectric microspeaker of claim 2, wherein the method further comprises:

prior to the forming the lower drive unit, etching a part of the substrate to form a cavity, wherein the lower drive unit is formed substantially within the cavity.

9. The piezoelectric microspeaker of claim 2, wherein the diaphragm is substantially planar.