Piezoelectric device and method for manufacturing the same

Abstract

A piezoelectric device includes: a substrate having an electrode terminal portion on an upper surface thereof, an electronic part arranged on an upper side of the substrate; and a piezoelectric resonator arranged on an upper side of the electronic part, wherein a surface of the electronic part opposite to a surface having a pad portion is bonded to a lower surface of the piezoelectric resonator having an external terminal portion and the pad portion of the electronic part and the external terminal portion of the piezoelectric resonator are wire-bonded to each other, and wherein the surface of the electronic part having the pad portion is mounted face down on the upper surface of the substrate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1A is a plan view schematically showing the piezoelectric oscillator, which is an example of a piezoelectric device according to a first embodiment of the present invention.

FIG. 1B is a schematic bottom view of the piezoelectric oscillator of FIG. 1B.

FIG. 2 is a schematic sectional view taken along the line A-A of FIG. 1A.

FIG. 3 is a view showing the steps of the method for manufacturing the piezoelectric oscillator according to the first embodiment of the present invention.

FIG. 4 is a view showing the substrate during the preparation process of FIG. 3.

FIG. 5A is a view relating to the step ST1 of FIG. 3.

FIG. 5B is a view relating to the step ST2 of FIG. 3.

FIG. 5C is a view relating to the step ST3 of FIG. 3.

FIG. 6 is a view relating to the steps ST4 and ST5 of FIG. 3.

FIG. 7 is a schematic perspective view showing the piezoelectric oscillator as an example of the piezoelectric device according to a second embodiment of the present invention seen from its bottom surface side.

FIG. 8 is a schematic sectional view taken along the line B-B of FIG. 7.

FIG. 9 is a view showing steps of the method for manufacturing the piezoelectric oscillator according to the second embodiment of the present invention.

FIG. 10 is a schematic view showing the substrate during the preparation process of FIG. 9.

FIG. 11A is a view relating to the step ST11 of FIG. 9.

FIG. 11B is a view relating to the step ST12 of FIG. 9.

FIG. 11C is a view relating to the step ST13 of FIG. 9.

FIG. 11D is a view relating to the step ST14 of FIG. 9.

FIG. 12 is a partially cutout view showing the internal structure of a conventional piezoelectric device.

Claims

1. A piezoelectric device, comprising: a substrate having an electrode terminal portion on an upper surface thereof;an electronic part arranged on an upper side of the substrate; anda piezoelectric resonator arranged on an upper side of the electronic part,wherein a surface of the electronic part opposite to a surface having a pad portion is bonded to a lower surface of the piezoelectric resonator having an external terminal portion and the pad portion of the electronic part and the external terminal portion of the piezoelectric resonator are wire-bonded to each other, andwherein the surface of the electronic part having the pad portion is face-down mounted on the upper surface of the substrate.

2. The piezoelectric device according to claim 1, wherein the electronic part is flip-chip connected to the substrate by using a bump and the height of the bump is greater than such a height that a wire for the wire bonding comes into contact with the substrate.

3. The piezoelectric device according to claim 1, wherein a portion defining one of a through hole and a cutout portion is formed so as to correspond to a position at which wire bonding of the pad portion and the external terminal portion is performed.

4. The piezoelectric device according to claim 1, wherein at least a space between the lower surface of the piezoelectric resonator and the upper surface of the substrate is molded by using resin so that the upper surface of the piezoelectric resonator is exposed to the outside.

5. A method for manufacturing a piezoelectric device, the piezoelectric device including a substrate having an electrode terminal portion on an upper surface thereof, an electronic part arranged on an upper side of the substrate, and a piezoelectric resonator arranged on an upper side of the electronic part, the method comprising: bonding a surface opposite to a surface of the electronic part having a pad portion to a lower surface of the piezoelectric resonator having an external terminal portion;performing wire bonding of the pad portion and the external terminal portion; andmounting the surface of the electronic part having the pad portion face down on the upper surface of the substrate.

6. A method for manufacturing a piezoelectric device, the piezoelectric device including a substrate having an electrode terminal portion on an upper surface thereof, an electronic part arranged on an upper side of the substrate, and a piezoelectric resonator arranged on an upper side of the electronic part, the method comprising: mounting a surface of the electronic part having the pad portion face down on the upper surface of the substrate;bonding a surface opposite to the surface of the electronic part having the pad portion to a lower surface of the piezoelectric resonator having an external terminal portion; andperforming wire bonding of the pad portion and the external terminal portion,wherein a portion defining one of a through hole and a cutout portion is formed in a portion in the substrate at which the wire bonding is performed prior to the wire bonding.