ACOUSTIC TRANSDUCER AND PACKAGE MODULE INCLUDING THE SAME

• US 20150110309A1
• Filed: 03/04/2014
• Published: 04/23/2015
• Est. Priority Date: 10/23/2013
• Status: Abandoned Application

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group), Tohoku University National Universities Corporation
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group), Tohoku University National Universities Corporation
• Inventors: Park, Yoon Sok, Esashi, Masayoshi, Kang, Pil Joong
• Application Number:
  US14/196,907
• Publication Number:
  US 20150110309A1
• Time in Patent Office: Days
• US Class Current: 381/190
• CPC Class Codes: B81B 2201/0257 Microphones or microspeakers
• CPC Class Codes: B81B 2203/0127 Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function
• CPC Class Codes: B81B 2203/019 characterized by their profile
• CPC Class Codes: B81B 3/0086 Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• 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 2924/16151 Cap comprising an aperture, e.g. for pressure control, encapsulation
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00
• CPC Class Codes: H04R 19/005 using semiconductor materials

Abstract

There is provided an acoustic transducer including an electrode substrate having a plurality of holes formed therein and having a first electrode thereon, a diaphragm disposed so as to face the electrode substrate and having a second electrode thereon to form an electric field in a space between the diaphragm and the electrode substrate, and a plurality of protrusions formed on the diaphragm and having the second electrode to form electric fields in the plurality of holes.

Claims

1. An acoustic transducer, comprising:

an electrode substrate having a plurality of holes and having a first electrode;

a diaphragm disposed so as to face the electrode substrate and having a second electrode to form an electric field in a space between the diaphragm and the electrode substrate; and

a plurality of protrusions formed on the diaphragm and having the second electrode to form electric fields in the holes of the electrode substrate.

2. The acoustic transducer of claim 1, wherein the protrusions are disposed so as to be inserted into the holes.

3. The acoustic transducer of claim 1, wherein the electrode substrate comprises doped silicon.

4. The acoustic transducer of claim 1, wherein the diaphragm comprises doped polysilicon.

5. The acoustic transducer of claim 1, wherein the protrusions are formed more in a center portion of the diaphragm than a periphery portion of the diaphragm.

6. The acoustic transducer of claim 1, wherein sizes of the holes become larger from a central portion of the diaphragm toward an edge of the diaphragm.

7. The acoustic transducer of claim 1, wherein a distance from the electrode substrate to the diaphragm is the same as a distance from an inner wall of the hole to an outer surface of the protrusion.

8. The acoustic transducer of claim 1, wherein the diaphragm includes one or more elastic support members extended in a meandering form.

9. The acoustic transducer of claim 1, further comprising an insulating layer formed between the electrode substrate and the diaphragm.

10. An acoustic transducer, comprising:

an electrode substrate having one or more first holes and a first electrode;

a diaphragm having a second electrode for forming an electric field in a space between the diaphragm and the electrode substrate;

a support substrate having one or more second holes and a third electrode to form the electric field in a space between the support substrate and the diaphragm; and

one or more first protrusions formed on one surface of the diaphragm and one or more second protrusions formed on another surface of the diaphragm, the first and second protrusions having the second electrode to form electric fields in inner walls of the first and second holes,

wherein the diaphragm is disposed between the electrode substrate and the support substrate.

11. The acoustic transducer of claim 10, wherein the first and second protrusions are inserted into the first and second holes.

12. The acoustic transducer of claim 10, wherein the electrode substrate and the support substrate comprise doped silicon.

13. The acoustic transducer of claim 10, wherein the diaphragm comprises doped polysilicon.

14. The acoustic transducer of claim 10, wherein the first and second protrusions are formed more in a center portion of the diaphragm than a periphery portion of the diaphragm.

15. The acoustic transducer of claim 10, wherein the first and second protrusions have a truncated conical shape, a truncated pyramidal shape, a multi-stage shape, or a shape having cross-sectional areas changed in a protruding direction, and

the first and second holes have shapes corresponding to those of the first and second protrusions, respectively.

16. The acoustic transducer of claim 10, wherein sizes of the first and second holes become larger from a central portion of the diaphragm toward an edge of the diaphragm.

17. The acoustic transducer of claim 10, wherein the diaphragm includes one or more elastic support members extended in a meandering form.

18. The acoustic transducer of claim 10, wherein the numbers of the first protrusions are the same as the numbers of the second protrusions, and

a magnitude of the electric field formed between the electrode substrate and the diaphragm and a magnitude of an electric field formed between the support substrate and the diaphragm are the same as each other when the diaphragm is in a stationary state.

19. The acoustic transducer of claim 10, further comprising insulating layers formed between the electrode substrate and the diaphragm and between the diaphragm and the support substrate, respectively.

20. An acoustic transducer, comprising:

a support substrate having an acoustic wave input chamber formed therein, the acoustic wave input chamber having acoustic waves input thereto;

a first electrode substrate having one or more first holes and a first electrode;

a second electrode substrate having one or more second holes and a second electrode; and

a diaphragm disposed between the first and second electrode substrates, and having protrusions formed thereon so as to be inserted into the first and second holes, the diaphragm having a third electrode.

21. The acoustic transducer of claim 20, wherein the protrusions are inserted into the first and second holes.

22. The acoustic transducer of claim 20, wherein the first and second electrode substrates comprise doped silicon.

23. The acoustic transducer of claim 20, wherein the diaphragm comprises doped polysilicon.

24. The acoustic transducer of claim 20, wherein the protrusions are formed more in a center portion of the diaphragm than a periphery portion of the diaphragm.

25. The acoustic transducer of claim 20, wherein the protrusions have a truncated conical shape, a truncated pyramidal shape, a multi-stage shape, or a shape having cross-sectional areas changed in a protruding direction, and

the first and second holes have shapes corresponding to those of the protrusions, respectively.

26. The acoustic transducer of claim 20, wherein sizes of the first and second holes become larger from a central portion of the diaphragm toward an edge of the diaphragm.

27. The acoustic transducer of claim 20, wherein the diaphragm includes one or more elastic support members extended in a meandering form.

28. The acoustic transducer of claim 20, wherein the numbers of the first protrusions are the same as the numbers of the second protrusions, and

a magnitude of an electric field formed between the first electrode substrate and the diaphragm and a magnitude of an electric field formed between the second electrode substrate and the diaphragm are the same as each other when the diaphragm is in a stationary state.

29. A package module comprising:

an acoustic transducer mounted on a circuit board; and

a semiconductor device mounted on the circuit board and connected to the acoustic transducer,

wherein the acoustic transducer comprises;

a diaphragm having at least three first electrode surfaces; and

an electrode substrate having second electrode surfaces corresponding to the first electrode surfaces.

30. The package module of claim 29, wherein the first electrode surfaces comprise:

a first plane of the diaphragm; and

surfaces with a plurality of protrusions extended from the first plane toward the electrode substrate.

31. The package module of claim 30, wherein the second electrode surfaces comprise:

a plane of the electrode substrate facing the first plane; and

inner surfaces of a plurality of holes into which the plurality of the protrusions are to be inserted.

32. The package module of claim 31, wherein the electrode substrate is disposed between the diaphragm and the circuit board.

33. The package module of claim 31, wherein the diaphragm is disposed between the electrode substrate and the circuit board.

34. The package module of claim 29, wherein the first electrode surfaces comprise:

a first plane of the diaphragm;

a second plane of the diaphragm; and

surfaces with a plurality of protrusions extended from the first and second planes in different directions.

35. The package module of claim 34, wherein the second electrode surfaces comprise:

a plurality of planes of the electrode substrate facing the first and second planes, respectively; and

inner surfaces of the plurality of holes formed in the planes, respectively, so that the plurality of protrusions are inserted thereinto, respectively.