MEMS microphone and method for manufacturing the same

• US 10,547,954 B2
• Filed: 03/12/2018
• Issued: 01/28/2020
• Est. Priority Date: 03/13/2017
• Status: Active Grant

• Current Assignee: Semiconductor Manufacturing International (Beijing) Corporation (Semiconductor Manufacturing International Corporation), Semiconductor Manufacturing International (Shanghai) Corporation (Semiconductor Manufacturing International Corporation)
• Original Assignee: Semiconductor Manufacturing International (Shanghai) Corporation (Semiconductor Manufacturing International Corporation)
• Inventors: Shi, Hui
• Primary Examiner(s): Zhu, Qin
• Application Number:
  US15/918,256
• Publication Number:
  US 20180262845A1
• Time in Patent Office: 687 Days
• Field of Search: None
• 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 2203/0307 Anchors
• CPC Class Codes: B81B 2203/04 Electrodes
• CPC Class Codes: B81B 3/007 For controlling stiffness, e.g. ribs
• CPC Class Codes: B81B 3/0078 Constitution or structural means for improving mechanical properties not provided for in B81B3/007 - B81B3/0075
• CPC Class Codes: B81C 1/00182 Arrangements of deformable or non-deformable structures, e.g. membrane and cavity for use in a transducer
• CPC Class Codes: B81C 1/00658 Treatments for improving the stiffness of a vibrating element
• CPC Class Codes: B81C 2201/0114 Electrochemical etching, anodic oxidation
• CPC Class Codes: H04R 19/005 using semiconductor materials
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 2201/003 Mems transducers or their use

Abstract

A microphone includes a substrate, an opening in the substrate, and a support structure in the opening. The support structure includes a first bracket formed in a closed-loop pattern and a second bracket connecting the first bracket to a periphery of the opening. The support structure in the opening increases the mechanical reliability of the microphone.

Claims

1. A microphone, comprising:

a substrate;

an opening in the substrate; and

a support structure in the opening and comprising a first bracket formed in a closed-loop pattern and a second bracket connecting the first bracket to a periphery of the opening,

wherein the second bracket comprises at least two portions spaced apart from each other, the at least two portions dividing an area between the first bracket and the periphery of the opening into a same number of regions.

2. The microphone of claim 1, wherein a cross-sectional area of the opening has a square-like shape including at least one curved corner.

3. The microphone of claim 2, wherein the square-like shape comprises four curved corners.

4. The microphone of claim 2, wherein the at least one curved corner comprises an arc of a circle having a radius equal to a length of the arc.

5. The microphone of claim 4, wherein the radius of the circle is in a range between 270 μ

m and 330 μ

m.

6. The microphone of claim 1, wherein the closed-loop pattern of the first bracket comprises a circular pattern, an oval pattern, a prismatic pattern, a square pattern, or a triangular pattern.

7. The microphone of claim 1, wherein the regions have a same surface area.

8. The microphone of claim 7, wherein the second bracket comprises four portions.

9. The microphone of claim 1, further comprising:

a first electrode plate on the opening, the first electrode plate comprising a square vibration portion and a fixed portion extending outwardly from at least one of four corners of the square vibration portion.

10. The microphone of claim 9, further comprising:

a second electrode plate above the first electrode plate and spaced apart from the first electrode plate.

11. The microphone of claim 1, wherein the second bracket comprises three portions.

12. A method for manufacturing a microphone, comprising:

providing a substrate having a top surface and a bottom surface;

forming a patterned mask on the bottom surface of the substrate, the patterned mask defining a shape of an opening; and

etching the substrate using the patterned mask as a mask to form the opening, the opening comprising a support structure having a first bracket formed in a closed-loop pattern and a second bracket connecting the first bracket to a periphery of the opening,

wherein the second bracket comprises at least two portions spaced apart from each other, the at least two portions dividing an area between the first bracket and the periphery of the opening into a same number of regions.

13. The method of claim 12, wherein a cross-sectional area of the opening has a square-like shape including at least one curved corner.

14. The method of claim 13, wherein the square-like shape comprises four curved corners.

15. The method of claim 13, wherein the at least one curved corner comprises an arc of a circle having a radius equal to a length of the arc.

16. The method of claim 15, wherein the radius of the circle is in a range between 270 μ

m and 330 μ

m.

17. The method of claim 12, wherein the closed-loop pattern of the first bracket comprises a circular pattern, an oval pattern, a prismatic pattern, a square pattern, or a triangular pattern.

18. The method of claim 12, wherein the regions have a same surface area.

19. The method of claim 12, wherein the second bracket comprises four portions.

20. The method of claim 12, wherein the second bracket comprises three portions.