Piezoelectric resonator unit, module component, and manufacturing method for same

Patent metadata

Field	Value
Publication number	US-2018167050-A1
Application number	US-201715823873-A
Country	US
Kind code	A1
Filing date	Nov 28, 2017
Priority date	Dec 12, 2016
Publication date	Jun 14, 2018
Grant date	—

Abstract

A piezoelectric resonator unit that includes a base, a piezoelectric resonator mounted on the base member, and a cover that is bonded to the base and that collectively forms an inner space that accommodates the piezoelectric resonator. The cover includes a top surface that faces the base with the piezoelectric resonator interposed therebetween, and a side wall that extends in a direction that intersects a main surface of the top surface. The piezoelectric resonator unit is designed so that the thickness of the top surface is larger than the thickness of the side wall.

First claim

What is claimed:

1 . A piezoelectric resonator unit comprising:
a base; a piezoelectric resonator disposed on the base; and a cover bonded to the base to form a space between the cover and the base that accommodates the piezoelectric resonator, the cover including a top surface that faces a main surface of the base with the piezoelectric resonator interposed therebetween, and at least one side wall that extends from the top surface of the cover in a direction towards the base, wherein the top surface has a first thickness that is larger than a second thickness of the at least one side wall.

2 . The piezoelectric resonator unit according to claim 1 , where T 1 represents the first thickness of the top surface and T 2 represents the second thickness of the at least one side wall, with 0.5<T 2 /T 1 <0.9.

3 . The piezoelectric resonator unit according to claim 2 , wherein 0.65<T 2 /T 1 <0.9.

4 . The piezoelectric resonator unit according to claim 3 , wherein 0.7<T 2 /T 1 <0.85.

5 . The piezoelectric resonator unit according to claim 2 , wherein the cover includes a flange that extends outward from the at least one side wall such that the flange is outside the top surface when seen in a plan view from a direction normal to a main surface of the top surface.

6 . The piezoelectric resonator unit according to claim 5 , wherein 0.5<T 2 /T 1 <0.85.

7 . The piezoelectric resonator unit according to claim 6 , wherein 0.5<T 2 /T 1 <0.7.

8 . The piezoelectric resonator unit according to claim 1 ,
wherein the cover includes a connection portion that connects the top surface and the at least one side wall to each other, and wherein at least an outer surface of the connection portion is curved.

9 . The piezoelectric resonator unit according to claim 8 , wherein a curvature of an inner surface of the connection portion is larger than a curvature of the outer surface of the connection portion.

10 . The piezoelectric resonator unit according to claim 8 , wherein a curvature of an inner surface of the connection portion and a curvature of the outer surface of the connection portion are substantially equal to each other.

11 . The piezoelectric resonator unit according to claim 5 , wherein the at least one side wall and the flange are connected to each other by a curved surface.

12 . The piezoelectric resonator unit according to claim 1 , wherein the piezoelectric resonator unit is covered by a sealing member.

13 . The piezoelectric resonator unit according to claim 1 , wherein the at least one side wall is configured to deform more easily than the top surface based on the first thickness of the top surface being greater than the second thickness of the side surface.

14 . The piezoelectric resonator unit according to claim 5 , wherein a combined thickness of the flange and the at least one side wall in direction parallel to the main surface of the base is greater than the second thickness of the at least one side wall.

15 . The piezoelectric resonator unit according to claim 1 , further comprising:
a sealing frame disposed on the main surface of the base; and a bonding member disposed on the sealing frame, such that the bonding member and the sealing frame collectively bond the cover to the base.

16 . A module component comprising:
a piezoelectric resonator unit including:
a base;
a piezoelectric resonator disposed on the base; and
a cover bonded to the base to form a space between the cover and the base that accommodates the piezoelectric resonator, wherein the cover includes a top surface that faces a main surface of the base with the piezoelectric resonator interposed therebetween, and at least one side wall that extends from the top surface of the cover in a direction towards the base, and
wherein the top surface has a first thickness that is larger than a second thickness of the at least one wall surface;
a circuit board; and a sealing member, wherein the piezoelectric resonator unit is mounted on the circuit board, and the sealing member is disposed on the circuit board to cover the piezoelectric resonator unit.

17 . The module component according to claim 16 , where T 1 represents the first thickness of the top surface and T 2 represents the second thickness of the at least one side wall, with 0.5<T 2 /T 1 <0.9.

18 . The module component according to claim 16 , wherein the cover includes a flange that extends outward from the at least one side wall, such that the flange is outside the top surface when seen in a plan view from a direction normal to a main surface of the top surface.

19 . A method for manufacturing a piezoelectric resonator unit, the method comprising:
mounting a piezoelectric resonator on a base; and bonding a cover to the base with the piezoelectric resonator accommodated in an inner space formed therebetween, the cover including a top surface and at least one side wall extending from the top surface towards the base to form the inner space, wherein the top surface has a thickness that is larger than a thickness of the at least one side wall, such that the at least one side wall deforms more easily than the top surface.

20 . The manufacturing method according to claim 1 , further comprising:
mounting the piezoelectric resonator unit on a circuit board; covering the piezoelectric resonator unit with a sealing member having fluidity; and curing the sealing member having fluidity.

Assignees

• Murata Manufacturing Co

Inventors

• Yoshii Kentaro
• Kaida Hiroaki
• Saeki Takashi

Classifications

• H03H9/19

  consisting of quartz · CPC title

• H03H9/02023 Primary

  consisting of quartz · CPC title

• H03H3/02 Primary

  for the manufacture of piezoelectric or electrostrictive resonators or networks (H03H3/08 takes precedence) · CPC title

• H03H9/1021

  the BAW device being of the cantilever type · CPC title

• H03H9/174

  Membranes · CPC title