Micro-electro-mechanical system structure

Abstract

This invention discloses a microelectromechanical system (MEMS) structure. The MEMS structure includes a substrate and a backplate. The substrate has an opening, and the backplate is disposed on one side of the substrate and has multiple acoustic holes. The MEMS structure also includes a diaphragm disposed between the substrate and the backplate and extending across the opening of the substrate. The diaphragm includes vent holes, and an air gap is formed between the diaphragm and the backplate. The MEMS structure further includes a protrusion extending into the air gap.

Description

Technical Field

[0001] This invention relates to an acoustic transducer, and more particularly to a micro-electro-mechanical system (MEMS) structure that can be used in a micro-electro-mechanical system microphone. Background Technology

[0002] The current trend in personal electronics is towards manufacturing thin, compact, lightweight, and high-performance electronic devices, including microphones. Microphones are used to receive sound waves and convert sound signals into electrical signals. Microphones are widely used in everyday life and installed in electronic products such as telephones, mobile phones, and voice recorders. In a condenser microphone, changes in acoustic pressure (i.e., local pressure deviations in ambient atmospheric pressure caused by sound waves) cause a corresponding deformation of the diaphragm, and this deformation leads to changes in capacitance. Therefore, changes in sound pressure can be obtained by detecting the voltage changes caused by changes in capacitance.

[0003] Unlike traditional electret condenser microphones (ECMs), microelectromechanical system (MEMS) microphones integrate their mechanical and electronic components onto semiconductor materials using integrated circuit (IC) technology to create miniature microphones. MEMS microphones offer advantages such as small size, lightweight design, and low power consumption, making them the mainstream choice for miniature microphones.

[0004] While existing MEMS microphones are generally sufficient for general use, they do not fully meet other requirements. For example, high-order microphones not only have high performance requirements for signal-to-noise ratio (SNR) and acoustic overload point (AOP), but also need to meet low-frequency roll-off (LFRO) requirements. Furthermore, phase mismatch between different MEMS microphones must be minimized. Summary of the Invention

[0005] The microelectromechanical system (MEMS) structure of this invention can be used in MEMS microphones, which includes a protrusion disposed on a backplate or diaphragm. In some embodiments, due to this protrusion, a shorter distance is formed between the protrusion and the diaphragm, which can increase acoustic resistance, thereby improving the signal-to-noise ratio (SNR). The protrusion can also reduce phase mismatch between MEMS microphones.

[0006] Some embodiments of the present invention include a microelectromechanical system (MEMS) structure. The MEMS structure includes a substrate and a backplate. The substrate has an opening, and the backplate is disposed on one side of the substrate and has a plurality of acoustic holes. The MEMS structure also includes a diaphragm disposed between the substrate and the backplate and extending across the opening of the substrate. The diaphragm includes vent holes, and an air gap is formed between the diaphragm and the backplate. The MEMS structure further includes a protrusion extending into the air gap.

[0007] In some embodiments, the protrusion extends from the backplate toward the diaphragm.

[0008] In some embodiments, the distance between the protrusion and the diaphragm is less than 0.5 μm.

[0009] In some embodiments, the protrusion extends from the diaphragm toward the backplate.

[0010] In some embodiments, in a top view of the microelectromechanical system structure, the protrusions are formed as a closed pattern.

[0011] In some embodiments, in a top view of the microelectromechanical system architecture, a closed pattern surrounds at least a portion of the vent.

[0012] In some embodiments, the sound hole is located on the outside of the closed pattern.

[0013] In some embodiments, the microelectromechanical system structure further includes a plurality of protrusions that extend into the air gap.

[0014] In some embodiments, in a top view of the microelectromechanical system structure, the protrusions are formed as multiple closed patterns.

[0015] In some embodiments, the closed patterns are connected to each other.

[0016] In some embodiments, the closed patterns are separated from each other.

[0017] In some embodiments, at least two closed patterns have the same center.

[0018] In some embodiments, the vent is surrounded by two or more closed patterns.

[0019] In some embodiments, the protrusions have different shapes in a top view of the microelectromechanical system structure.

[0020] In some embodiments, in a top view of the microelectromechanical system structure, the protrusion is formed as a curve.

[0021] In some embodiments, in a top view of the microelectromechanical system structure, at least one acoustic hole is located on the side of the protrusion away from the center of the back panel.

[0022] In some embodiments, the microelectromechanical system (MEMS) structure further includes a dielectric layer disposed between the substrate and the diaphragm and between the diaphragm and the backplate. The dielectric layer has an inner edge, and the orthographic projection of a sound hole on the diaphragm is located between the orthographic projection of the inner edge on the diaphragm and the orthographic projection of the protrusion on the diaphragm.

[0023] In some embodiments, in a top view of the microelectromechanical system structure, the protrusions are formed as a non-closed zigzag pattern. Attached Figure Description

[0024] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, according to industry standard practice, the various feature components are not drawn to scale. In fact, the dimensions of the various feature components may be enlarged or reduced to clearly demonstrate the technical features of the embodiments of the present invention.

[0025] Figure 1A This is a partial cross-sectional view of a microphone for a microelectromechanical system (MEMS) according to some embodiments of the present invention;

[0026] Figure 1B This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0027] Figure 1C This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0028] Figure 1D This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0029] Figure 1E This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0030] Figure 2A This is a partial cross-sectional view of a microphone for a microelectromechanical system (MEMS) according to some embodiments of the present invention;

[0031] Figure 2B This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0032] Figure 2C This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0033] Figure 3A This is a partial cross-sectional view of a microphone for a microelectromechanical system (MEMS) according to some embodiments of the present invention;

[0034] Figure 3B This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0035] Figure 3C This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0036] Figure 4A This is a partial cross-sectional view of a microphone for a microelectromechanical system (MEMS) according to some embodiments of the present invention;

[0037] Figure 4B This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0038] Figure 4C This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0039] Figure 5A This is a partial cross-sectional view of a microphone for a microelectromechanical system (MEMS) according to some embodiments of the present invention;

[0040] Figure 5B This is a partial top view showing the relationship between the protrusion and the vent holes of the diaphragm;

[0041] Figure 5C This is a partial top view showing the relationship between the protrusion and the acoustic openings on the back panel;

[0042] Figure 6A This is a partial top view illustrating the relationship between the protrusion and the vent hole of the diaphragm or the relationship between the protrusion and the acoustic hole of the back plate in some embodiments of the present invention.

[0043] Figure 6B This is a partial top view illustrating the relationship between the protrusion and the vent hole of the diaphragm or the relationship between the protrusion and the acoustic hole of the back plate, which are some other embodiments of the present invention.

[0044] Figure 7 , Figure 8 , Figure 9 and Figure 10 This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone, illustrating some other embodiments of the present invention.

[0045] Symbol Explanation

[0046] 10: Microelectromechanical System Structure

[0047] 11:Substrate

[0048] 11A: Opening portion

[0049] 12: Dielectric layer

[0050] 121: Inner Edge

[0051] 13: Back panel

[0052] 131: Conductive layer

[0053] 132: Insulation layer

[0054] 1321: First insulating layer

[0055] 1322: Second insulating layer

[0056] 133, 133-1, 133-2, 133-3, 133-4: Protrusions

[0057] 13A, 13A1: Acoustic port

[0058] 14: Diaphragm

[0059] 14A: Vent

[0060] 141: Protrusion

[0061] 15: Electrode layer

[0062] C13: Center of the backplate

[0063] C133: Center

[0064] d: distance

[0065] G: Air gap

[0066] M: Microelectromechanical Systems Microphone

[0067] P: Sound wave path Detailed Implementation

[0068] The following disclosure provides many different embodiments or examples to implement different features of this invention. Specific examples of the various components and their arrangements described below are provided to simplify the invention. Of course, these are merely examples and not intended to be limiting. For example, if it is stated that a first feature is formed on or above a second feature, it may include embodiments where the first and second feature are in direct contact, or embodiments where other feature is formed between the first and second feature, so that the first and second feature may not be in direct contact.

[0069] It should be understood that other operational steps may be performed before, between, or after the method, and in other embodiments of the method, some operational steps may be replaced or omitted.

[0070] Furthermore, spatially related terms such as "below," "under," "down," "above," "above," and similar terms may be used herein to facilitate the description of the relationship between one element or feature and other elements or features in the accompanying drawings. These spatially related terms encompass different orientations of the device in use or operation, as well as the orientations described in the accompanying drawings. The device may be turned to different orientations (rotated 90 degrees or other orientations), and the spatially related adjectives used herein will be interpreted in accordance with the orientation after the turn.

[0071] In this invention, the terms "about," "approximately," and "substantially" generally mean within 20%, 10%, 5%, 3%, 2%, 1%, or even 0.5% of a given value. The given values ​​in this invention are approximate values. That is, even without a specific description of "about," "approximately," or "substantially," the given value may still include the meaning of "about," "approximately," or "substantially."

[0072] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should be understood that these terms, such as those defined in commonly used dictionaries, should be interpreted in a meaning consistent with the context of the relevant art and will not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of the invention.

[0073] The same reference numerals and / or designations may be used repeatedly in the following embodiments. These repetitions are for simplification and clarity and are not intended to limit any specific relationship between the various embodiments and / or structures discussed.

[0074] Figure 1A This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some embodiments of the present invention. For example, the MEMS microphone M may be a condenser microphone. Figure 1A As shown, the microelectromechanical system (MEMS) microphone M includes a MEMS structure 10. In some embodiments, the MEMS structure 10 includes a substrate 11, a dielectric layer 12, a backplate 13, a diaphragm 14, and an electrode layer 15. It should be noted that, for the sake of simplicity... Figure 1A Some components of the microelectromechanical system microphone M (microelectromechanical system structure 10) have been omitted.

[0075] The substrate 11 is used to support the dielectric layer 12, backplate 13, diaphragm 14, and electrode layer 15 located on one side of the substrate 11. For example... Figure 1AAs shown, in some embodiments, substrate 11 has an opening 11A. The opening 11A allows sound waves received by the microelectromechanical system microphone M to pass through and / or enter the microelectromechanical system structure 10. For example, substrate 11 may contain silicon or the like, but the embodiments of the present invention are not limited thereto.

[0076] A dielectric layer 12 is disposed between the substrate 11 and the diaphragm 14, and between the diaphragm 14 and the backplate 13. In other words, the diaphragm 14 is inserted into the dielectric layer 12 to provide partial isolation between the substrate 11, the diaphragm 14, and the backplate 13. Furthermore, the dielectric layer 12 is disposed around the backplate 13 and the diaphragm 14, such that the edges of the backplate 13 and the diaphragm 14 are supported by the dielectric layer 12. The dielectric layer 12 may be made of silicon oxide or the like.

[0077] The back plate 13 is a fixing element disposed on one side of the substrate 11. The back plate 13 may have sufficient stiffness to prevent bending or movement when sound waves pass through it. For example, the back plate 13 may be a rigid perforated element, but this is not a limitation of the embodiments of the present invention. Figure 1A As shown, in some embodiments, the back panel 13 includes a plurality of acoustic holes 13A, each of which extends through the back panel 13. The acoustic holes 13A are configured to allow sound waves to pass through.

[0078] like Figure 1A As shown, the backplate 13 may include a conductive layer 131 and an insulating layer 132, with the insulating layer 132 covering the conductive layer 131 to provide protection. The insulating layer 132 may further include a first insulating layer 1321 and a second insulating layer 1322. Figure 1A As shown, conductive layer 131 may be disposed on dielectric layer 12, first insulating layer 1321 may be disposed on conductive layer 131, and second insulating layer 1322 may be disposed on first insulating layer 1321. For example, conductive layer 131 may contain polysilicon or the like, and insulating layer 132 (e.g., first insulating layer 1321 and second insulating layer 1322) may contain silicon nitride or the like, but the embodiments of the present invention are not limited thereto. Furthermore, first insulating layer 1321 and second insulating layer 1322 may contain the same material or different materials.

[0079] The microelectromechanical system (MEMS) structure 10 can be electrically connected to a circuit (not shown) via multiple electrode pads of electrode layer 15, which is disposed on backplate 13 and electrically connected to conductive layer 131 and diaphragm 14. For example, electrode layer 15 may comprise copper, silver, gold, aluminum, the like, their alloys, or combinations thereof.

[0080] A diaphragm 14 is disposed between a substrate 11 and a backplate 13, and extends across an opening 11A in the substrate 11. The diaphragm 14 is movable or displaceable relative to the backplate 13. The diaphragm 14 is configured to sense sound waves received by a microelectromechanical system (MEMS) microphone M. Figure 1A As shown, in some embodiments, the diaphragm 14 includes ventilation holes 14A, and an air gap G is formed between the diaphragm 14 and the back plate 13. Sound waves pass through the diaphragm 14 through the ventilation holes 14A to reach the air gap G, and then pass through the back plate 13 through the acoustic holes 13A.

[0081] More specifically, the displacement of the diaphragm 14 relative to the back plate 13 causes a change in capacitance between the diaphragm 14 and the back plate 13. This capacitance change is then converted into an electrical signal by the circuit connected to the diaphragm 14 and the back plate 13, and this electrical signal is sent out of the microelectromechanical system microphone M through the electrode layer 15.

[0082] On the other hand, to improve the sensitivity of the diaphragm 14, multiple vent holes 14A can be provided in the diaphragm 14 to reduce the rigidity of the diaphragm 14. In some embodiments, more than two vent holes 14A may exist. Utilizing this structural feature, high sensitivity of the microelectronic system microphone M can be achieved. Furthermore, the vent holes 14A in the diaphragm 14 are also configured to release high air pressure on the diaphragm 14.

[0083] In some embodiments, the microelectromechanical system structure 10 further includes a protrusion 133 extending into the air gap G. (Refer to...) Figure 1A In some embodiments, the protrusion 133 extends from the backplate 13 toward the diaphragm 14. For example, the protrusion 133 may comprise a conductive material, such as polysilicon. Alternatively, the protrusion 133 may comprise a dielectric material, such as silicon nitride, but the embodiments of the present invention are not limited thereto.

[0084] like Figure 1A As shown, in some embodiments, the distance d between the protrusion 133 and the diaphragm 14 is less than about 0.5 μm. Furthermore, in some embodiments, the dielectric layer 12 has an inner edge 121, and the orthographic projection of a sound hole 13A (e.g., sound hole 13A1) on the diaphragm 14 lies between the orthographic projection of the inner edge 121 on the diaphragm 14 and the orthographic projection of the protrusion 133 on the diaphragm 14.

[0085] The protrusion 133 reduces the critical dimension of the acoustic path P, which increases acoustic impedance and thus improves the signal-to-noise ratio (SNR). Furthermore, the distance d reduces the dimensional variations in manufacturing, thereby reducing phase mismatch between microphones in the microelectromechanical system.

[0086] Figure 1BThis is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 1C This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. It should be noted that... Figure 1B and Figure 1C Possibly with Figure 1A Not a perfect match, and for the sake of brevity... Figure 1B and Figure 1C Some components have been omitted.

[0087] Reference Figure 1B In some embodiments, in a top view of the microelectromechanical system structure 10, the protrusions 133 are formed as closed patterns. In this embodiment, two or more protrusions 133 are formed as quadrilateral-like closed patterns. Furthermore, in Figure 1B In the illustrated embodiment, the closed patterns formed by the protrusions 133 are separated from each other.

[0088] In some embodiments, the closed pattern formed by the protrusion 133 surrounds at least a portion of the vent 14A. For example, such as Figure 1B As shown in the top view of the microelectromechanical system structure 10, each quadrilateral-like protrusion 133 may surround a complete C-shaped vent 14A, but the embodiments of the present invention are not limited thereto.

[0089] Reference Figure 1C In some embodiments, the acoustic holes 13A of the back plate 13 are located outside the closed pattern formed by the protrusions 133. More specifically, in Figure 1C In the illustrated embodiment, some sound holes 13A are provided on the side of the protrusion 133 near the center C13 of the back plate 13, while at least one sound hole 13A is provided on the side of the protrusion 133 away from the center C13 of the back plate 13.

[0090] Figure 1D This is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 1E This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. Similarly, Figure 1D and Figure 1E Possibly with Figure 1A Not a perfect match, and for the sake of brevity... Figure 1D and Figure 1E Some components have been omitted.

[0091] Reference Figure 1D In some embodiments, in the top view of the microelectromechanical system structure 10, the protrusion 133 is formed as a non-closed zigzag pattern. Furthermore, in... Figure 1DIn the illustrated embodiment, the non-closed zigzag pattern formed by the protrusions 133 is separated from each other.

[0092] In some embodiments, the non-closed zigzag pattern formed by the protrusion 133 surrounds at least a portion of the vent 14A. For example, such as Figure 1D As shown in the top view of the microelectromechanical system structure 10, each protrusion 133 formed as a non-closed zigzag pattern can surround a complete C-shaped vent 14A, but the embodiments of the present invention are not limited thereto.

[0093] Reference Figure 1E In some embodiments, the acoustic holes 13A of the back plate 13 are located on the outside of the non-closed zigzag pattern formed by the protrusions 133. More specifically, in Figure 1E In the illustrated embodiment, some sound holes 13A are provided on the side of the protrusion 133 near the center C13 of the back plate 13, while at least one sound hole 13A is provided on the side of the protrusion 133 away from the center C13 of the back plate 13.

[0094] Figure 2A This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some embodiments of the present invention. Figure 2B This is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 2C This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. It should be noted that... Figure 2B and Figure 2C Possibly with Figure 2A Not a perfect match, and for the sake of brevity... Figure 2A , Figure 2B and Figure 2C Some components have been omitted.

[0095] Reference Figure 2B In some embodiments, in a top view of the microelectromechanical system structure 10, the protrusions 133 are formed as closed patterns. In this embodiment, two or more protrusions 133 are formed as quadrilateral-like closed patterns. Furthermore, in Figure 2B In the illustrated embodiment, the closed patterns formed by the protrusions 133 are connected to each other.

[0096] like Figure 2B As shown in the top view of the microelectromechanical system structure 10, each quadrilateral-like protrusion 133 surrounds a complete C-shaped vent 14A, but the embodiments of the present invention are not limited thereto.

[0097] Reference Figure 2C In some embodiments, the acoustic holes 13A of the back plate 13 are located outside the closed pattern formed by the protrusions 133. More specifically, in Figure 2C In the illustrated embodiment, some sound holes 13A are provided on the side of the protrusion 133 near the center C13 of the back plate 13, while at least one sound hole 13A is provided on the side of the protrusion 133 away from the center C13 of the back plate 13.

[0098] Figure 3A This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some embodiments of the present invention. Figure 3B This is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 3C This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. It should be noted that... Figure 3B and Figure 3C Possibly with Figure 3A Not a perfect match, and for the sake of brevity... Figure 3A , Figure 3B and Figure 3C Some components have been omitted.

[0099] Reference Figure 3B In some embodiments, in a top view of the microelectromechanical system structure 10, the protrusions 133 are formed as closed patterns. In this embodiment, two or more protrusions 133 are formed as quadrilateral-like closed patterns. Furthermore, in Figure 3B In the illustrated embodiment, the closed patterns formed by the protrusions 133 are separated from each other.

[0100] like Figure 3B As shown in the top view of the microelectromechanical system structure 10, each quadrilateral-like protrusion 133 surrounds a complete C-shaped vent 14A and some other shaped vents 14A, but the embodiments of the present invention are not limited thereto.

[0101] Reference Figure 3C In some embodiments, the acoustic holes 13A of the back plate 13 are located outside the closed pattern formed by the protrusions 133. More specifically, in Figure 3C In the illustrated embodiment, some sound holes 13A are provided on the side of the protrusion 133 near the center C13 of the back plate 13, while at least one sound hole 13A is provided on the side of the protrusion 133 away from the center C13 of the back plate 13.

[0102] Figure 4A This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some embodiments of the present invention. Figure 4B This is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 4C This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. It should be noted that... Figure 4B and Figure 4C Possibly with Figure 4A Not a perfect match, and for the sake of brevity... Figure 4A , Figure 4B and Figure 4C Some components have been omitted.

[0103] Reference Figure 4B In some embodiments, in a top view of the microelectromechanical system structure 10, the protrusions 133 are formed as closed patterns. In this embodiment, two or more protrusions 133 are formed as circular closed patterns. Furthermore, in Figure 4B In the illustrated embodiment, the closed patterns formed by the protrusions 133 are separated from each other.

[0104] like Figure 4B As shown in the top view of the microelectromechanical system structure 10, each circular protrusion 133 surrounds a complete circular vent 14A, but the embodiments of the present invention are not limited thereto.

[0105] Reference Figure 4C In some embodiments, the sound hole 13A of the back plate 13 is disposed on the outside of the closed pattern formed by the protrusion 133.

[0106] Figure 5A This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some embodiments of the present invention. Figure 5B This is a partial top view showing the relationship between the protrusion 133 and the vent 14A of the diaphragm 14. Figure 5C This is a partial top view showing the relationship between the protrusion 133 and the sound hole 13A of the back plate 13. It should be noted that... Figure 5B and Figure 5C Possibly with Figure 5A Not a perfect match, and for the sake of brevity... Figure 5A , Figure 5B and Figure 5C Some components have been omitted.

[0107] Reference Figure 5B In some embodiments, in a top view of the microelectromechanical system structure 10, the protrusions 133 are formed as closed patterns. In this embodiment, two or more protrusions 133 are formed as circular closed patterns. Furthermore, in Figure 5B In the illustrated embodiment, the closed patterns formed by the protrusions 133 are separated from each other.

[0108] In some embodiments, at least two closed patterns have the same center. For example, such as Figure 5BAs shown in the top view of the microelectromechanical system structure 10, the two closed patterns formed by the protrusions 133 have the same center C133 (i.e., the two circular protrusions 133 are arranged in concentric circles), but the embodiments of the present invention are not limited thereto. Furthermore, in Figure 5B In the illustrated embodiment, each vent 14A is surrounded by two (or more) protrusions 133.

[0109] Reference Figure 5C In some embodiments, the sound hole 13A of the back plate 13 is disposed on the outside of the closed pattern formed by the protrusion 133.

[0110] Figure 6A This is a partial top view illustrating the relationship between the protrusion 133 and the vent 14A of the diaphragm 14, or the relationship between the protrusion 133 and the acoustic hole 13A of the back plate 13, according to some embodiments of the present invention. Figure 6B This is a partial top view illustrating the relationship between the protrusion 133 and the vent 14A of the diaphragm 14, or the relationship between the protrusion 133 and the acoustic hole 13A of the back plate 13, according to some other embodiments of the present invention. Similarly, for the sake of brevity, Figure 6A and Figure 6B Some components have been omitted.

[0111] Reference Figure 6A and Figure 6B In some embodiments, the protrusion 133 has different shapes in the top view of the microelectromechanical system structure 10.

[0112] like Figure 6A As shown, protrusion 133-1 is formed as a curve, while protrusions 133-2 and 133-3 are formed as a closed pattern resembling a quadrilateral. Protrusions 133-2 and 133-3 have different dimensions, and each surrounds a complete C-shaped vent 14A, but the embodiments of the present invention are not limited thereto.

[0113] like Figure 6B As shown, protrusions 133-2 and 133-4 form a closed pattern resembling a quadrilateral. Protrusions 133-2 and 133-4 have different dimensions, and each surrounds a complete C-shaped vent 14A and some other C-shaped vents 14A, but the embodiments of the present invention are not limited thereto.

[0114] Figure 7 , Figure 8 , Figure 9 and Figure 10 This is a partial cross-sectional view of a microelectromechanical system (MEMS) microphone M according to some other embodiments of the present invention. Similarly, for the sake of brevity, Figure 7 , Figure 8 , Figure 9and Figure 10 Some components have been omitted from the original text. Figure 7 , Figure 8 , Figure 9 and Figure 10 In the illustrated embodiment, the microelectromechanical system structure 10 includes a protrusion 141 that extends into the air gap G and extends from the diaphragm 14 toward the backplate 13.

[0115] Figure 7 The microelectromechanical system structure 10 shown has the same characteristics as... Figure 2A The microelectromechanical system structure 10 shown is similar in structure to the one described above, except for the protrusion 141. In other words, Figure 7 The protrusion 141 shown can replace Figure 2A The protrusion 133 is shown. Therefore, a partial top view of the relationship between the protrusion 141 and the vent 14A of the diaphragm 14 can be similar to... Figure 2B The partial top view of the relationship between the protrusion 141 and the acoustic hole 13A of the back plate 13 can be similar to... Figure 2C However, the embodiments of the present invention are not limited thereto.

[0116] Figure 8 The microelectromechanical system structure 10 shown has the same characteristics as... Figure 3A The microelectromechanical system structure 10 shown is similar in structure to the one described above, except for the protrusion 141. In other words, Figure 8 The protrusion 141 shown can replace Figure 3A The protrusion 133 is shown. Therefore, a partial top view of the relationship between the protrusion 141 and the vent 14A of the diaphragm 14 can be similar to... Figure 3B The partial top view of the relationship between the protrusion 141 and the acoustic hole 13A of the back plate 13 can be similar to... Figure 3C However, the embodiments of the present invention are not limited thereto.

[0117] Figure 9 The microelectromechanical system structure 10 shown has the same characteristics as... Figure 4A The microelectromechanical system structure 10 shown is similar in structure to the one described above, except for the protrusion 141. In other words, Figure 9 The protrusion 141 shown can replace Figure 4A The protrusion 133 is shown. Therefore, a partial top view of the relationship between the protrusion 141 and the vent 14A of the diaphragm 14 can be similar to... Figure 4B The partial top view of the relationship between the protrusion 141 and the acoustic hole 13A of the back plate 13 can be similar to... Figure 4C However, the embodiments of the present invention are not limited thereto.

[0118] Figure 10 The microelectromechanical system structure 10 shown has the same characteristics as... Figure 5AThe microelectromechanical system structure 10 shown is similar in structure to the one described above, except for the protrusion 141. In other words, Figure 10 The protrusion 141 shown can replace Figure 5A The protrusion 133 is shown. Therefore, a partial top view of the relationship between the protrusion 141 and the vent 14A of the diaphragm 14 can be similar to... Figure 5B The partial top view of the relationship between the protrusion 141 and the acoustic hole 13A of the back plate 13 can be similar to... Figure 5C However, the embodiments of the present invention are not limited thereto.

[0119] In summary, in the embodiments of the present invention, because the microelectromechanical system (MEMS) structure includes protrusions extending into the air gap, and these protrusions reduce the critical dimensions of the acoustic wave path, they can increase acoustic impedance, thereby improving the signal-to-noise ratio (SNR). Furthermore, the protrusions can reduce phase mismatch between MEMS microphones using this MEMS structure.

[0120] The foregoing outlines the features of several embodiments to enable those skilled in the art to better understand the viewpoints of the embodiments of the present invention. Those skilled in the art should understand that they can design or modify other manufacturing processes and structures based on the embodiments of the present invention to achieve the same purpose and / or advantages as the embodiments described herein. Those skilled in the art should also understand that such equivalent structures do not depart from the spirit and scope of the present invention, and that various changes, substitutions, and replacements can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims. Furthermore, although the present invention has been disclosed above with reference to several embodiments, it is not intended to limit the present invention.

[0121] References to features, advantages, or similar language throughout this specification do not imply that all features and advantages achievable using this invention should or may be implemented in any single embodiment of the invention. Rather, language relating to features and advantages is to be understood as meaning that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the invention. Thus, the discussion of features and advantages, as well as similar language, throughout this specification may, but does not necessarily, represent the same embodiments.

[0122] Furthermore, in one or more embodiments, the features, advantages, and characteristics described in this invention can be combined in any suitable manner. Based on the description herein, those skilled in the art will recognize that the invention can be implemented without one or more specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be identified in certain embodiments that may not be present in all embodiments of the invention.

Claims

1. A microelectromechanical system (MEMS) architecture, comprising: The substrate has an opening. A back plate is disposed on one side of the substrate and has multiple acoustic holes; A diaphragm is disposed between the substrate and the back plate, extends across the opening portion of the substrate, and includes a vent hole, wherein an air gap is formed between the diaphragm and the back plate. as well as The protrusion extends into the air gap. In a top view of the microelectromechanical system structure, the protrusion is formed as a closed pattern, wherein the closed pattern surrounds at least a portion of the vent.

2. The microelectromechanical system structure as claimed in claim 1, wherein the protrusion extends from the backplate toward the diaphragm.

3. The microelectromechanical system structure as described in claim 2, wherein the distance between the protrusion and the diaphragm is less than 0.5 μm.

4. The microelectromechanical system structure as claimed in claim 1, wherein the protrusion extends from the diaphragm toward the backplate.

5. The microelectromechanical system structure as claimed in claim 1, wherein the acoustic holes are disposed on the outer side of the closed pattern.

6. The microelectromechanical system architecture as described in claim 1, further comprising: Multiple protrusions extend into the air gap.

7. The microelectromechanical system structure as claimed in claim 6, wherein, in a top view of the microelectromechanical system structure, the protrusions are formed as a plurality of closed patterns.

8. The microelectromechanical system structure of claim 7, wherein the closed patterns are interconnected.

9. The microelectromechanical system structure of claim 7, wherein the closed patterns are separated from each other.

10. The microelectromechanical system structure of claim 7, wherein at least two of the closed patterns have the same center.

11. The microelectromechanical system structure of claim 7, wherein the vent is surrounded by two or more of the closed patterns.

12. The microelectromechanical system structure of claim 7, wherein, in a top view of the microelectromechanical system structure, the protrusions have different shapes.

13. The microelectromechanical system structure as claimed in claim 1, wherein, in a top view of the microelectromechanical system structure, the protrusion is formed as a curve.

14. The microelectromechanical system structure as claimed in claim 1, wherein, in a top view of the microelectromechanical system structure, at least one of the acoustic holes is located on the side of the protrusion away from the center of the back plate.

15. The microelectromechanical system architecture as described in claim 1, further comprising: A dielectric layer is disposed between the substrate and the diaphragm, and between the diaphragm and the backplate. The dielectric layer has an inner edge, and the orthographic projection of one of the acoustic holes on the diaphragm is located between the orthographic projection of the inner edge on the diaphragm and the orthographic projection of the protrusion on the diaphragm.

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