Microphone
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.
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,
wherein the communication hole causes the through-hole and the hollow space to communicate with each other,
wherein the microphone further comprises a sealing member that seals the hollow space, and
wherein the sealing member is disposed so as to surround the hollow space between the sensor substrate and the circuit element.
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 2 , wherein the through-hole and the communication hole are made in plural.
7. 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.
8. 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.
9. 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.
10. 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.
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 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.
13. 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.
14. 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.
15. 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.