WO2013071950A1 - Mems backplate, mems microphone comprising a mems backplate and method for manufacturing a mems microphone - Google Patents

Mems backplate, mems microphone comprising a mems backplate and method for manufacturing a mems microphone Download PDF

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Publication number
WO2013071950A1
WO2013071950A1 PCT/EP2011/070067 EP2011070067W WO2013071950A1 WO 2013071950 A1 WO2013071950 A1 WO 2013071950A1 EP 2011070067 W EP2011070067 W EP 2011070067W WO 2013071950 A1 WO2013071950 A1 WO 2013071950A1
Authority
WO
WIPO (PCT)
Prior art keywords
backplate
mems
anchor element
area
sua
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/EP2011/070067
Other languages
French (fr)
Inventor
Leif Steen Johansen
Jan Tue Ravnkilde
Pirmin Rombach
Kurt Rasmussen
Dennis Mortensen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TDK Electronics AG
Original Assignee
Epcos AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Epcos AG filed Critical Epcos AG
Priority to PCT/EP2011/070067 priority Critical patent/WO2013071950A1/en
Priority to JP2014540328A priority patent/JP5914684B2/en
Priority to DE112011105847.0T priority patent/DE112011105847B4/en
Priority to US13/261,882 priority patent/US9266713B2/en
Publication of WO2013071950A1 publication Critical patent/WO2013071950A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
    • B81B3/0064—Constitution or structural means for improving or controlling the physical properties of a device
    • B81B3/0086—Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
    • B81C1/00015—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems
    • B81C1/00134—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems comprising flexible or deformable structures
    • B81C1/00158—Diaphragms, membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
    • B81C1/00642—Manufacture or treatment of devices or systems in or on a substrate for improving the physical properties of a device
    • B81C1/00698—Electrical characteristics, e.g. by doping materials
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
    • H04R19/00—Electrostatic transducers
    • H04R19/005—Electrostatic transducers using semiconductor materials
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
    • H04R31/00—Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor
    • H04R31/006—Interconnection of transducer parts
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
    • H04R2201/00—Details of transducers, loudspeakers or microphones covered by H04R1/00 but not provided for in any of its subgroups
    • H04R2201/003—Mems transducers or their use
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24273—Structurally defined web or sheet [e.g., overall dimension, etc.] including aperture

Definitions

  • MEMS backplate MEMS microphone comprising a MEMS backplate and method for manufacturing a MEMS microphone
  • the present invention relates to MEMS backplates, MEMS microphones with reduced parasitic capacitance and a method for manufacturing such microphones.
  • MEMS microphones usually comprise a conductive backplate and a conductive, flexible membrane being arranged in a distance from the backplate.
  • the backplate and the membrane realize electrodes of a capacitor.
  • oscillations of the membrane caused by received acoustic signals are converted into electrical sig ⁇ nals.
  • MEMS-microphones can com ⁇ prise an ASIC (Application-specific Integrated Circuit) chip.
  • Such Microphones have a central, acoustically active area and a suspension area.
  • the central area is surrounded by the suspension area being acoustically inactive.
  • suspension means for mechanically and/or electrically connecting the backplate and/or the membrane are arranged on a substrate material.
  • manufacturing processes of semi-conductor devices such as layer deposition, deposition of photo resist films, structuring photoresist films, and partly removing structured layers can be utilized.
  • the capacitor - apart from the central area - has an acoustically inactive area
  • H c C m / (C m +Ci+C p ) , (1)
  • Ci is the input capacitance of an according ASIC chip processing the electrical signal.
  • C p is the parasitic ca ⁇ pacitance, i.e. the capacitance of the capacitor's acousti ⁇ cally inactive area.
  • C m is the total capacitance comprising the capacitance of the central area and the capacitance of the suspension area. Reducing the parasitic capacitance reduces the signal's deterioration and, thus, improves the microphone's signal quality.
  • C p mainly depends on the acoustically inactive suspension area of the backplate overlapping a suspension area of the membrane.
  • the independent claims provide a MEMS backplate, a MEMS microphone and a method for manufacturing such a
  • a MEMS backplate comprises a central area, a perforation in the central area, a suspension area, and an aperture in the suspension area.
  • the suspension area surrounds the central area at least partially.
  • perforation refers to holes in the central area while “apertures” refers to holes in the suspension area of the MEMS backplate. Both categories of holes can be arranged in a regular pattern such as a
  • irregular lattice places can be added to the holes of a regular pattern. Such additional holes can have a bigger or smaller diameter.
  • the apertures can be larger than the holes of the perforation, or vice-versa. It is also possible that the apertures have the same size as the holes of the
  • the unwanted parasitic capacitance depends on the amount of the acoustically inactive area, i.e. the suspension area, of the backplate and of the membrane. Further, the capacitance depends on the dielectric constant of the material in-between these electrodes.
  • An aperture in the suspension area of the backplate reduces the acoustically inactive but electrically active amount of conductive area of the backplate resulting in an improved signal quality of the respective MEMS microphone.
  • the suspension area can comprise two or more, e.g. a
  • mechanically stable microphone can be obtained although the area for suspending the backplate is reduced. Further, it was found that apertures in the suspension area of the backplate enable methods for manufacturing MEMS microphones with further reduced parasitic capacitances while maintaining the mechanical stability.
  • the suspension area surrounds the central area completely. Then, a MEMS backplate is provided that enables an optimal mechanical stability of a respective MEMS microphone .
  • the MEMS backplate and/or the respective membrane can have a circular or an elliptic shape. It is further possible that the MEMS backplate and the membrane have a rectangular or a quadratic shape.
  • the suspension area comprises a plurality of apertures.
  • the MEMS backplate comprises a plurality of apertures which are comprised in aperture sections.
  • the apertures are concentrated in the aperture sections while other sections of the suspension area do not comprise
  • the MEMS backplate can be optimized with respect to electric capacitance and mechanical stability.
  • the MEMS backplate has aperture sections which are arranged in equal distances with respect to their neighboring aperture sections.
  • the aperture sections can be arranged in a symmetric pattern within the suspension area .
  • a MEMS microphone can comprise one of the above mentioned backplates.
  • the microphone can further comprises a substrate, a membrane, and an anchor element.
  • the membrane is arranged between the substrate and the anchor element.
  • the backplate suspension area is connected to the anchor element.
  • the anchor element comprises connection sections.
  • the suspension area of the MEMS backplate comprises aperture sections, each comprising at least one aperture.
  • the connection sections of the anchor element are connected to the backplate suspension area.
  • connection elements can be arranged using the same symmetry but an offset relative to the pattern of the aperture
  • the parasitic capacitance can be reduced by establishing cavities within the anchor element which can comprise dielectric material.
  • the parasitic capacitance depends on the dielectric constant of the anchor element. The absence of dielectric material of the anchor element within the cavities reduces, thus, the parasitic capacitance as vacuum or an ambient atmosphere has a lower dielectric constant than the anchor element's material.
  • the anchor element still comprises connection sections being connected to the backplate suspension area, a mechanically stable microphone is obtained.
  • the cavities are arranged within the anchor element.
  • a method for manufacturing a MEMS microphone comprises the steps :
  • apertures further allow to create cavities within the anchor element as they enable removing material of the anchor element during manufacturing of the MEMS microphone through the aperture holes.
  • material of the anchor element is removed using a VHF (Vapor Hydro-Fluoric) etching environment .
  • VHF Vapor Hydro-Fluoric
  • FIG. 1 shows a top view onto a MEMS microphone indicating the positions of cross-section A and cross-section
  • FIG. 2A shows cross-section A indicated in FIG. 1,
  • FIG. 2B shows the cross-section B indicated in FIG.
  • FIG. 3 shows an enlarged view of the rim of a backplate
  • FIG. 4 shows an anchor element comprising cavities.
  • FIG. 1 shows a top view of a MEMS microphone MM.
  • microphone MM comprises a substrate SU on which a backplate BP is arranged.
  • Backplate BP comprises a central area CA and a suspension area SUA.
  • the suspension area SUA surrounds the central area CA.
  • the central area CA is the acoustically active area of the backplate BP while the suspension area SUA is acoustically inactive and, due to the contribution of the parasitic capacitance C P in equation (1), generally
  • the backplate BP comprises aperture sections AS within the suspension area SUA.
  • the aperture sections AS comprise apertures as shown in FIG. 3. Due to the apertures in the aperture sections AS, the acoustically inactive but
  • apertures in the aperture sections AS allow to create MEMS microphones with further reduced parasitic capacitances: during a manufacturing step, material of an anchor element below the backplate BP can be removed via the apertures of the aperture sections. This is shown in FIGs. 2A and 2B which illustrate cross-sections A, B.
  • the aperture sections AS can be arranged in equal distances with respect to their neighboring aperture sections AS.
  • FIG. 2A shows cross-section A illustrated in FIG. 1.
  • the MEMS microphone comprises a membrane M being arranged on substrate SU.
  • An anchor element AE is arranged on membrane M.
  • the backplate BP is arranged on the anchor element AE .
  • Connection sections CS of the anchor element AE are connected to the suspension area SUA of backplate BP.
  • FIG. 2B shows cross-section B illustrated in FIG. 1.
  • Cross- section B intersects aperture sections AS within the
  • the aperture sections AS comprise apertures AP .
  • material of the anchor element AE shown in FIG. 2A, is removed.
  • cavities CV below the aperture sections AS are obtained.
  • the parasitic capacitance is reduced as dielectric material having a larger dielectric constant than air or vacuum is replaced by air or vacuum within the cavities CV.
  • FIG. 3 shows an enlarged view of the rim of a backplate BP.
  • the perforation PF comprises holes HO. Holes HO are arranged in a hexagonal pattern. However, other patterns such as rectangular or quadratic patterns or irregular patterns are also possible.
  • Aperture section AS comprises a plurality of apertures AP .
  • the aperture section AS, and thus the apertures AP, are arranged within the suspension area SUA which serves as a connection means to connect the backplate BP to the body of the MEMS microphone, e. g. via an anchor element AE .
  • the apertures AP within the aperture section AS can also be arranged in a hexagonal, rectangular, quadratic or irregular pattern.
  • the aperture sections AS themselves can have a circular, rectangular, quadratic or irregular shape.
  • the holes HO of the perforation can be larger than the apertures within the aperture sections, or vice-versa. It is also possible that the apertures AP and the holes HO of the perforation PF have the same size.
  • apertures AP and holes HO are created during the same manufacturing step.
  • FIG. 4 shows a circular shaped anchor element AE comprising cavities CV.
  • the cavities CV reduce the average dielectric constant of the anchor element AE reducing the parasitic capacitance C P .
  • the position and size of cavities CV can be optimized with respect to mechanical stability and reduced parasitic capacitance simultaneously.
  • Backplates comprising further structured elements and microphones comprising further layers and methods for manufacturing microphones comprising further manufacturing steps are also comprised by the present invention.
  • A cross-sections through solid sections of anchor element
  • CA central area

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Computer Hardware Design (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
  • Pressure Sensors (AREA)

Abstract

A MEMS backplate enabling MEMS microphones with reduced parasitic capacitance is provided. Therefore, the backplate comprises apertures in a suspension area.

Description

Description
MEMS backplate, MEMS microphone comprising a MEMS backplate and method for manufacturing a MEMS microphone
The present invention relates to MEMS backplates, MEMS microphones with reduced parasitic capacitance and a method for manufacturing such microphones. MEMS microphones usually comprise a conductive backplate and a conductive, flexible membrane being arranged in a distance from the backplate. The backplate and the membrane realize electrodes of a capacitor. When a bias voltage is applied to the electrodes, then oscillations of the membrane caused by received acoustic signals are converted into electrical sig¬ nals. For further signal processing MEMS-microphones can com¬ prise an ASIC (Application-specific Integrated Circuit) chip.
Such Microphones have a central, acoustically active area and a suspension area. The central area is surrounded by the suspension area being acoustically inactive. Within the suspension area, suspension means for mechanically and/or electrically connecting the backplate and/or the membrane are arranged on a substrate material. For constructing MEMS microphones, manufacturing processes of semi-conductor devices such as layer deposition, deposition of photo resist films, structuring photoresist films, and partly removing structured layers can be utilized. As a consequence of the necessity for suspension means the capacitor - apart from the central area - has an acoustically inactive area
deteriorating the signal quality of the microphone. This deterioration is due to parasitic capacitance. The
corresponding signal attenuation Hc is: Hc=Cm/ (Cm+Ci+Cp) , (1) where Ci is the input capacitance of an according ASIC chip processing the electrical signal. Cp is the parasitic ca¬ pacitance, i.e. the capacitance of the capacitor's acousti¬ cally inactive area. Cm is the total capacitance comprising the capacitance of the central area and the capacitance of the suspension area. Reducing the parasitic capacitance reduces the signal's deterioration and, thus, improves the microphone's signal quality.
Cp mainly depends on the acoustically inactive suspension area of the backplate overlapping a suspension area of the membrane.
It is an object of the present invention to provide a MEMS backplate that can be used in a MEMS microphone having reduced parasitic capacitance, a MEMS microphone with reduced parasitic capacitance and a method for manufacturing such a microphone .
Therefore, the independent claims provide a MEMS backplate, a MEMS microphone and a method for manufacturing such a
microphone. Dependent claims provide preferred embodiments of the invention.
A MEMS backplate comprises a central area, a perforation in the central area, a suspension area, and an aperture in the suspension area. The suspension area surrounds the central area at least partially. In this context, the phrase "perforation" refers to holes in the central area while "apertures" refers to holes in the suspension area of the MEMS backplate. Both categories of holes can be arranged in a regular pattern such as a
quadratic pattern or a hexagonal pattern or in a irregular pattern. It is also possible that additional holes at
irregular lattice places can be added to the holes of a regular pattern. Such additional holes can have a bigger or smaller diameter. The apertures can be larger than the holes of the perforation, or vice-versa. It is also possible that the apertures have the same size as the holes of the
perforation .
The unwanted parasitic capacitance depends on the amount of the acoustically inactive area, i.e. the suspension area, of the backplate and of the membrane. Further, the capacitance depends on the dielectric constant of the material in-between these electrodes. An aperture in the suspension area of the backplate reduces the acoustically inactive but electrically active amount of conductive area of the backplate resulting in an improved signal quality of the respective MEMS microphone. The suspension area can comprise two or more, e.g. a
plurality of, apertures in the suspension area.
It was found that such a MEMS backplate reduces the parasitic capacitance of a respective MEMS microphone and a
mechanically stable microphone can be obtained although the area for suspending the backplate is reduced. Further, it was found that apertures in the suspension area of the backplate enable methods for manufacturing MEMS microphones with further reduced parasitic capacitances while maintaining the mechanical stability.
In one embodiment, the suspension area surrounds the central area completely. Then, a MEMS backplate is provided that enables an optimal mechanical stability of a respective MEMS microphone .
The MEMS backplate and/or the respective membrane can have a circular or an elliptic shape. It is further possible that the MEMS backplate and the membrane have a rectangular or a quadratic shape.
In one embodiment, the suspension area comprises a plurality of apertures.
In one embodiment, the MEMS backplate comprises a plurality of apertures which are comprised in aperture sections. Thus, the apertures are concentrated in the aperture sections while other sections of the suspension area do not comprise
apertures and maintain their mechanical stiffness required for a stable suspension.
Thus, the MEMS backplate can be optimized with respect to electric capacitance and mechanical stability.
In one embodiment, the MEMS backplate has aperture sections which are arranged in equal distances with respect to their neighboring aperture sections. Thus, the aperture sections can be arranged in a symmetric pattern within the suspension area . A MEMS microphone can comprise one of the above mentioned backplates. The microphone can further comprises a substrate, a membrane, and an anchor element. The membrane is arranged between the substrate and the anchor element. The backplate suspension area is connected to the anchor element.
In one embodiment, the anchor element comprises connection sections. The suspension area of the MEMS backplate comprises aperture sections, each comprising at least one aperture. The connection sections of the anchor element are connected to the backplate suspension area. The backplate aperture
sections are, then, arranged above cavities within the anchor element. Corresponding to a symmetry of the arrangement of the aperture sections of the suspension section the
connection elements can be arranged using the same symmetry but an offset relative to the pattern of the aperture
sections . It was found that the parasitic capacitance can be reduced by establishing cavities within the anchor element which can comprise dielectric material. The parasitic capacitance depends on the dielectric constant of the anchor element. The absence of dielectric material of the anchor element within the cavities reduces, thus, the parasitic capacitance as vacuum or an ambient atmosphere has a lower dielectric constant than the anchor element's material. As the anchor element still comprises connection sections being connected to the backplate suspension area, a mechanically stable microphone is obtained.
Thus, in one embodiment, the cavities are arranged within the anchor element. A method for manufacturing a MEMS microphone comprises the steps :
- providing a substrate,
- structuring a membrane on the substrate,
- structuring an anchor element on the membrane,
- structuring a backplate on the anchor element creating a perforation in a central area of the backplate and creating apertures in a suspension area of the backplate,
- removing material of the anchor element in a region below the apertures.
Thus, the apertures within the suspension area of the
backplate not only reduce the electrically active area of the capacitor resulting in the parasitic capacitance. The
apertures further allow to create cavities within the anchor element as they enable removing material of the anchor element during manufacturing of the MEMS microphone through the aperture holes.
It is possible that material of the anchor element between the backplate and the membrane is removed while material of the anchor element below the aperture sections is removed.
In one embodiment of the method, material of the anchor element is removed using a VHF (Vapor Hydro-Fluoric) etching environment .
The basic idea of the invention and embodiments are shown in the schematic figures. Brief description of the figures:
FIG. 1 shows a top view onto a MEMS microphone indicating the positions of cross-section A and cross-section
FIG. 2A shows cross-section A indicated in FIG. 1,
FIG. 2B shows the cross-section B indicated in FIG.
FIG. 3 shows an enlarged view of the rim of a backplate,
FIG. 4 shows an anchor element comprising cavities.
FIG. 1 shows a top view of a MEMS microphone MM. The
microphone MM comprises a substrate SU on which a backplate BP is arranged. Backplate BP comprises a central area CA and a suspension area SUA. The suspension area SUA surrounds the central area CA. The central area CA is the acoustically active area of the backplate BP while the suspension area SUA is acoustically inactive and, due to the contribution of the parasitic capacitance CP in equation (1), generally
deteriorates the microphone's signal quality. However, the backplate BP comprises aperture sections AS within the suspension area SUA. The aperture sections AS comprise apertures as shown in FIG. 3. Due to the apertures in the aperture sections AS, the acoustically inactive but
electrically active suspension area SUA is reduced. Thus, parasitic capacitance CP is reduced.
Further, the apertures in the aperture sections AS allow to create MEMS microphones with further reduced parasitic capacitances: during a manufacturing step, material of an anchor element below the backplate BP can be removed via the apertures of the aperture sections. This is shown in FIGs. 2A and 2B which illustrate cross-sections A, B.
The aperture sections AS can be arranged in equal distances with respect to their neighboring aperture sections AS.
FIG. 2A shows cross-section A illustrated in FIG. 1. The MEMS microphone comprises a membrane M being arranged on substrate SU. An anchor element AE is arranged on membrane M. The backplate BP is arranged on the anchor element AE . Connection sections CS of the anchor element AE are connected to the suspension area SUA of backplate BP. Thus, a mechanically stable connection between the backplate BP and the body of the microphone is obtained. A perforation PF of the
acoustically active region of the backplate BP comprises holes . FIG. 2B shows cross-section B illustrated in FIG. 1. Cross- section B intersects aperture sections AS within the
suspension area SUA.
The aperture sections AS comprise apertures AP . Below the apertures AP, material of the anchor element AE, shown in FIG. 2A, is removed. Thus, cavities CV below the aperture sections AS are obtained. Correspondingly, the parasitic capacitance is reduced as dielectric material having a larger dielectric constant than air or vacuum is replaced by air or vacuum within the cavities CV.
FIG. 3 shows an enlarged view of the rim of a backplate BP. The perforation PF comprises holes HO. Holes HO are arranged in a hexagonal pattern. However, other patterns such as rectangular or quadratic patterns or irregular patterns are also possible. Aperture section AS comprises a plurality of apertures AP . The aperture section AS, and thus the apertures AP, are arranged within the suspension area SUA which serves as a connection means to connect the backplate BP to the body of the MEMS microphone, e. g. via an anchor element AE .
The apertures AP within the aperture section AS can also be arranged in a hexagonal, rectangular, quadratic or irregular pattern. The aperture sections AS themselves can have a circular, rectangular, quadratic or irregular shape.
The holes HO of the perforation can be larger than the apertures within the aperture sections, or vice-versa. It is also possible that the apertures AP and the holes HO of the perforation PF have the same size.
It is possible that apertures AP and holes HO are created during the same manufacturing step.
FIG. 4 shows a circular shaped anchor element AE comprising cavities CV. The cavities CV reduce the average dielectric constant of the anchor element AE reducing the parasitic capacitance CP . The position and size of cavities CV can be optimized with respect to mechanical stability and reduced parasitic capacitance simultaneously.
A MEMS backplate, a MEMS microphone or a method for
manufacturing such microphones are not limited to the
embodiments described in the specification or shown in the figures. Backplates comprising further structured elements and microphones comprising further layers and methods for manufacturing microphones comprising further manufacturing steps are also comprised by the present invention.
List of reference signs:
A: cross-sections through solid sections of anchor element
AE : anchor element
AP: aperture
AS : aperture section
B: cross-sections through aperture sections
BP: backplate
CA: central area
CS : connection section
CV: cavity
HO: hole of perforation PF
M: membrane
MM: MEMS microphone
PF: perforation
SU: substrate
SUA: suspension area

Claims

Claims
1. A MEMS backplate (BP), comprising
- a central area (CA) , a perforation (PF) in the central area (CA) ,
- a suspension area (SUA) , and an aperture (AP) in the suspension area (SUA) , where
- the suspension area (SUA) surrounds the central area (CA) at least partially.
2. The MEMS backplate of the previous claim, where the suspension area (SUA) surrounds the central area (CA) completely .
3. The MEMS backplate of one of the previous claim, where the suspension area (SUA) comprises a plurality of apertures (AP) .
4. The MEMS backplate of the previous claim, where the plurality of apertures (AP) are comprised in aperture
sections (AS) .
5. The MEMS backplate of the previous claim, where the aperture sections (AS) are arranged in equal distances with respect to their neighboring aperture sections (AS) .
6. A MEMS microphone (MM) comprising a MEMS backplate (BP) of one of the previous claims, further comprising
- a substrate (SU) , a membrane (M) , and an anchor element (AE) , where
- the membrane (M) is arranged between the substrate (SU) and the anchor element (AE) , - the backplate's suspension area (SUA) is connected to the anchor element (AE) .
7. The MEMS microphone of the previous claim, where
- the anchor element (AE) comprises connection sections (CS),
- the suspension area (SUA) comprises aperture sections (AS),
- the connection sections (CS) are connected to the
backplate's suspension area (SUA), and
- the backplate's aperture sections (AS) are arranged above cavities (CV) .
8. The MEMS microphone of the previous claim, where the cavities (CV) are arranged within the anchor element (AE) .
9. A Method for manufacturing a MEMS microphone, comprising the steps
- providing a subtrate (SU) ,
- structuring a membrane (M) on the substrate (SU) ,
- structuring an anchor element (AE) on the membrane (M) , - structuring a backplate (BP) on the anchor element (AE) creating a perforating (PF) a central area (CA) of the backplate (BP) and creating apertures (AP) in a suspension area (SUA) of the backplate (BP) ,
- removing material of the anchor element (AE) in a region below the apertures (AP) .
10. The Method of the previous claim, where material of the anchor element (AE) is removed using a VHF etching
environment .
PCT/EP2011/070067 2011-11-14 2011-11-14 Mems backplate, mems microphone comprising a mems backplate and method for manufacturing a mems microphone Ceased WO2013071950A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
PCT/EP2011/070067 WO2013071950A1 (en) 2011-11-14 2011-11-14 Mems backplate, mems microphone comprising a mems backplate and method for manufacturing a mems microphone
JP2014540328A JP5914684B2 (en) 2011-11-14 2011-11-14 MEMS back plate, MEMS microphone provided with MEMS back plate, and method of manufacturing MEMS microphone
DE112011105847.0T DE112011105847B4 (en) 2011-11-14 2011-11-14 MEMS microphone with reduced parasitic capacitance and method of manufacture
US13/261,882 US9266713B2 (en) 2011-11-14 2011-11-14 MEMS backplate, MEMS microphone comprising a MEMS backplate and method for manufacturing a MEMS microphone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2011/070067 WO2013071950A1 (en) 2011-11-14 2011-11-14 Mems backplate, mems microphone comprising a mems backplate and method for manufacturing a mems microphone

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WO2013071950A1 true WO2013071950A1 (en) 2013-05-23

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US (1) US9266713B2 (en)
JP (1) JP5914684B2 (en)
DE (1) DE112011105847B4 (en)
WO (1) WO2013071950A1 (en)

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JP2017508394A (en) * 2014-03-03 2017-03-23 エプコス アクチエンゲゼルシャフトＥｐｃｏｓ Ａｇ Non-circular membrane condenser microphone

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112334867B (en) 2018-05-24 2025-11-11 纽约州立大学研究基金会 Capacitive sensor

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070201710A1 (en) * 2006-02-24 2007-08-30 Yamaha Corporation Condenser microphone

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4737721B2 (en) 2006-03-10 2011-08-03 ヤマハ株式会社 Condenser microphone
ATE471635T1 (en) * 2006-03-30 2010-07-15 Sonion Mems As SINGLE-CHIP ACOUSTIC MEMS TRANSDUCER AND MANUFACTURING METHOD
JP2010098454A (en) 2008-10-15 2010-04-30 Canon Inc Mechanoelectric transducer element
DE102009026677A1 (en) 2009-06-03 2010-12-09 Robert Bosch Gmbh Semiconductor component with a micromechanical microphone structure
US8590136B2 (en) 2009-08-28 2013-11-26 Analog Devices, Inc. Method of fabricating a dual single-crystal backplate microphone

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070201710A1 (en) * 2006-02-24 2007-08-30 Yamaha Corporation Condenser microphone

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017508394A (en) * 2014-03-03 2017-03-23 エプコス アクチエンゲゼルシャフトＥｐｃｏｓ Ａｇ Non-circular membrane condenser microphone
US10419858B2 (en) 2014-03-03 2019-09-17 Tdk Corporation Condenser microphone with non-circular membrane

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