Method of manufacturing a piezoelectric component

• US 8,332,995 B2
• Filed: 06/19/2009
• Issued: 12/18/2012
• Est. Priority Date: 06/24/2008
• Status: Active Grant

• Current Assignee: Nihon Dempa Kogyo Company Limited
• Original Assignee: Nihon Dempa Kogyo Company Limited
• Inventors: Tsuda, Toshimasa
• Primary Examiner(s): Tugbang, A. Dexter
• Application Number:
  US12/456,654
• Publication Number:
  US 20090315430A1
• Time in Patent Office: 1,278 Days
• Field of Search: 29/253.5, 298/42, 298/46, 298/52, 310/322, 310/340, 310/348, 310/365
• US Class Current: 29/25.35
• CPC Class Codes: H03H 9/1092 the enclosure being defined by a cover cap mounted on an element forming part of the surface acoustic wave [SAW] device on the side of the IDT's
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49147 Assembling terminal to base
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base

Abstract

A piezoelectric component manufacturing method is provided. The method includes preparing an integrated piezoelectric substrate, and forming comb-shaped electrodes and wiring electrodes having element wiring connecting to the comb-shape electrodes on a primary surface of the piezoelectric substrate, forming an SiO₂ layer, performing a characteristics inspection on the piezoelectric substrate and marking defective piezoelectric elements, coating said SiO₂ layer surface with photosensitive resin, and then exposing and developing to form an insulating layer. The method includes vapor-depositing a metal layer, and removing said metal layer adhered to resist by an organic solvent when removing the resist, to form a rewiring layer, coating said rewiring layer with photosensitive resin, affixing a photosensitive resin film to a top end surface of said photosensitive resin layer, forming electrode posts in the holes by electroplating, and dicing said piezoelectric substrate along scribe lines to obtain individual piezoelectric components.

Claims

1. A piezoelectric component manufacturing method comprising:

a step for preparing an integrated piezoelectric substrate, and forming comb-shaped electrodes and wiring electrodes having element wiring connecting to the comb-shape electrodes on a primary surface of the piezoelectric substrate, by sputtering or vapor deposition;

a step for forming an SiO₂ layer by coating an entire primary surface of said piezoelectric substrate on which said comb-shaped electrodes and said wiring electrodes are formed;

a step for performing a characteristics inspection on the piezoelectric substrate and marking defective piezoelectric elements;

a step for coating said SiO₂ layer surface, excluding at least said comb-shaped electrodes and said wiring electrodes, with photosensitive resin, and then exposing and developing to form an insulating layer;

a step for vapor-depositing a metal layer serving as an adhesion layer and an electrode layer on a surface of said insulating layer, and removing said metal layer adhered to resist by an organic solvent when removing the resist, to form a rewiring layer;

a step for coating said rewiring layer, excluding said comb-shaped electrodes and said wiring electrode forming section, with photosensitive resin, and then exposing and developing to form a photosensitive resin layer which forms outer wall sections;

a step for affixing a photosensitive resin film to a top end surface of said photosensitive resin layer, and then exposing and developing to form ceiling sections, and at the same time removing said photosensitive resin layer and said photosensitive film at the region where electrode posts are to be formed, to form holes;

a step for forming electrode posts in the holes by electroplating; and

a step for dicing, after said electroplating is completed, said piezoelectric substrate along scribe lines to obtain individual piezoelectric components.

2. A piezoelectric component manufacturing method according to claim 1, wherein said rewiring layer is formed before spreading of photosensitive resist, and in a later step after spreading of the photosensitive resist, unnecessary portions of the spread resist are removed by wet etching.

3. A piezoelectric component manufacturing method according to claim 1, wherein after forming said electrode posts, a distributed constant circuit is formed on a rear surface of said ceiling section, and a terminal electrode is formed on an other end of said electrode post.

4. A piezoelectric component manufacturing method according to claim 1, wherein a hole for said electrode post formation, is formed by dry etching using laser light or reactive gas.

5. A piezoelectric component manufacturing method according to claim 1, wherein said piezoelectric substrate is thinned by grinding from a facing side of said comb-shape electrodes, after forming individual piezoelectric components.

6. A piezoelectric component manufacturing method according to claim 1, wherein an insulating layer made from an organic material such as photopolyimide, or epoxy is formed on a surface of a resin seal section made from said outer wall section and said ceiling section.

7. A piezoelectric component manufacturing method according to claim 1, wherein said electrode posts are formed by Cu electroplating, and terminal electrodes formed on the end of said electrode post are formed by Ni and Au electroless plating.

8. A piezoelectric component manufacturing method according to claim 1, wherein terminal electrodes formed on the tip end of said electrode post are formed by electroless plating or electroplating with only Au, or with Ni, Pd and Au.

9. A piezoelectric component manufacturing method according to claim 1, wherein an adhesion layer made from Cr is deposited on said insulating layer, and a conductor layer made from Cu is deposited on the Cr to form said rewiring layer.

10. A piezoelectric component manufacturing method according to claim 1, wherein a conductor layer of said rewiring layer is formed by vapor-depositing Cu and Al, or by sputtering Ti, W, and Cu, or by sputtering Ti, W, and Al.