MICROPHONE

• US 20140306299A1
• Filed: 03/25/2014
• Published: 10/16/2014
• Est. Priority Date: 04/12/2013
• Status: Active Grant

• Current Assignee: MMI Semiconductor Company Limited
• Original Assignee: Omron Corporation
• Inventors: Kasai, Masaaki
• Granted Patent: US 9,126,823 B2
• Time in Patent Office: Days
• US Class Current: 257/416
• CPC Class Codes: B81B 3/0027 Structures for transforming mechanical energy, e.g. potential energy of a spring into translation, sound into translation
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/15151 the die mounting substrate comprising an aperture, e.g. for underfilling, outgassing, window type wire connections
• CPC Class Codes: H04R 1/04 Structural association of microphone with electric circuitry therefor in deaf-aid sets H04R25/00
• CPC Class Codes: H04R 1/2807 Enclosures comprising vibrating or resonating arrangements for the reduction of undesired resonances or vibrations H04R1/2869
• CPC Class Codes: H04R 19/005 using semiconductor materials
• CPC Class Codes: H04R 31/006 Interconnection of transducer parts of diaphragm and outer suspension by moulding H04R31/003

Abstract

A microphone has a base substrate comprising a main surface, an acoustic sensor mounted on the main surface, and a circuit element stacked on the acoustic sensor. A hollow space is formed between the acoustic sensor and the circuit element. The acoustic sensor has a sensor substrate having a first surface opposed to the base substrate, a second surface on a side opposite to the first surface, and a cavity formed while recessed with respect to the second surface, and a movable electrode that covers the cavity from the second surface side. A through-hole is formed in the base substrate while piercing the base substrate in a thickness direction. A communication hole is formed in the sensor substrate while piercing the sensor substrate from the first surface to the second surface. The communication hole causes the through-hole and the hollow space to communicate with each other.

Claims

1. A microphone comprising:

a base substrate comprising a main surface;

an acoustic sensor mounted on the main surface; and

a circuit element stacked on the acoustic sensor,

wherein a hollow space is formed between the acoustic sensor and the circuit element,

wherein the acoustic sensor comprises;

a sensor substrate comprising;

a first surface opposed to the base substrate,

a second surface on a side opposite to the first surface, and

a cavity formed while recessed with respect to the second surface, and

a movable electrode that covers the cavity from the second surface side,

wherein a through-hole is formed in the base substrate while piercing the base substrate in a thickness direction,

wherein a communication hole is formed in the sensor substrate while piercing the sensor substrate from the first surface to the second surface, and

wherein the communication hole causes the through-hole and the hollow space to communicate with each other.

2. The microphone according to claim 1, wherein a diameter of the through-hole is formed larger than that of the communication hole.

3. The microphone according to claim 1, wherein the through-hole and the communication hole are made in plural.

4. The microphone according to claim 1,

wherein a recess formed in at least one of the main surface and the first surface, and

wherein an adhesive cured material in which a liquid adhesive is cured is accommodated in part of the recess.

5. The microphone according to claim 1,

wherein the base substrate comprises a projection projected from the main surface, and

wherein the projection is projected from the main surface along a circumferential edge of the through-hole.

6. The microphone according to claim 1, further comprising:

a sealing member that seals the hollow space,

wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.

7. The microphone according to claim 2, wherein the through-hole and the communication hole are made in plural.

8. The microphone according to claim 2,

wherein a recess formed in at least one of the main surface and the first surface, and

wherein an adhesive cured material in which a liquid adhesive is cured is accommodated in part of the recess.

9. The microphone according to claim 3,

wherein a recess formed in at least one of the main surface and the first surface, and

wherein an adhesive cured material in which a liquid adhesive is cured is accommodated in part of the recess.

10. The microphone according to claim 2,

wherein the base substrate comprises a projection projected from the main surface, and

wherein the projection is projected from the main surface along a circumferential edge of the through-hole.

11. The microphone according to claim 3,

wherein the base substrate comprises a projection projected from the main surface, and

wherein the projection is projected from the main surface along a circumferential edge of the through-hole.

12. The microphone according to claim 4,

wherein the base substrate comprises a projection projected from the main surface, and

wherein the projection is projected from the main surface along a circumferential edge of the through-hole.

13. The microphone according to claim 2, further comprising:

a sealing member that seals the hollow space,

wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.

14. The microphone according to claim 3, further comprising:

a sealing member that seals the hollow space,

wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.

15. The microphone according to claim 4, further comprising:

a sealing member that seals the hollow space,

wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.

16. The microphone according to claim 5, further comprising:

a sealing member that seals the hollow space,

wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.