JP5513813B2 - MEMS microphone and manufacturing method thereof - Google Patents

Description

  The present invention relates to a MEMS microphone and a method of manufacturing the same, and in particular, a capacitor is formed by disposing a diaphragm film having a vibrating electrode on a back chamber and a back plate film having a fixed electrode facing each other through an air gap. The present invention relates to a MEMS microphone and a manufacturing method thereof.

  The technology developed in the semiconductor process has been widely applied in the field of micromachining technology for processing small machines. Research and development of small microphones (MEMS microphones) are underway using such micromachining technology. The MEMS microphone includes a back plate film having a fixed electrode, a diaphragm film having a vibration electrode that vibrates by sound waves, and a spacer that secures and supports an air gap (vibration space) between the back plate film and the diaphragm film. Prepare. In the MEMS microphone, when the diaphragm film vibrates due to the sound pressure, the capacitance of the flat plate capacitor composed of the back plate film and the diaphragm film changes, and is output as a voltage change. Detected.

  FIG. 6 shows an example of a cross-sectional structure of a conventional MEMS microphone. A conventional MEMS microphone 61 shown in FIG. 6 includes a silicon substrate 81, a first insulating layer 82 provided on the silicon substrate 81, and a diaphragm film provided on the first insulating layer 82 and having a vibrating electrode 63. 83, a spacer 66 formed on the first insulating layer 82 by the second insulating layer 84 and having an air gap 64 on the inside thereof, and a fixed portion that is supported by the spacer 66 and faces the vibration electrode 63 through the air gap 64. A back plate film 85 having an electrode 65 and electrode portions 68 connected to the vibrating electrode 63 and the fixed electrode 65 are provided.

  In the conventional MEMS microphone 61, an opening is provided in the silicon substrate 81 at a position corresponding to the vibration electrode 63, and a back chamber 71 and a back chamber side wall 72 are formed. The diaphragm film 83 is formed of, for example, a conductive polysilicon film. Further, the back plate film 85 serving as a fixed electrode is formed by laminating, for example, a conductive polysilicon film 85a and a silicon nitride film 85b that applies a tensile stress to the conductive polysilicon film. The back plate film 85 is formed with a plurality of through holes 85c communicating with the front and back of the back plate film 85 so as not to disturb the vibration of the diaphragm film 83.

  7 and 8 are cross-sectional views showing a conventional method for manufacturing a MEMS microphone. A conventional MEMS microphone manufacturing method will be described below with reference to FIGS.

  A silicon substrate 81 is prepared. For example, a silicon substrate 81 having a crystal orientation (100) plane is used. Then, a thermal oxide film having a thickness of 0.2 μm is formed as the first insulating layer 82 on the surface of the silicon substrate 81 by, for example, thermal oxidation. (Step (6A), FIG. 7 (a))

  On the first insulating layer 82 formed on the surface of the silicon substrate 81, a diaphragm film 83 serving as a vibration electrode is formed. As the diaphragm film 83, for example, a 0.1 μm silicon nitride film and a 1.0 μm polysilicon film are stacked and deposited using a CVD (Chemical Vapor Deposition) apparatus. Then, the deposited diaphragm film 83 is processed into a predetermined shape using known lithography and etching techniques. (Step (6B), FIG. 7 (b))

  A second insulating layer 84 is formed on the first insulating layer 82 and the diaphragm film 83 formed on the first insulating layer 82. As the second insulating layer 84, for example, an NSG (Non-doped Silicate Glass) film having a film thickness of 3 μm is deposited. (Step (6C), FIG. 7 (c))

  On the second insulating layer 84, a back plate film 85 to be a fixed electrode is formed. As the back plate film 85, for example, a polysilicon film 85a having a thickness of 1 μm and a silicon nitride film 85b having a thickness of 0.2 μm are deposited, and the back plate film 85 is formed into a predetermined shape by using known lithography and etching techniques. Process. The back plate film 85 is formed with a through hole 85 c that communicates the front and back of the back plate film 85. The size of the through hole 85c is, for example, a circular shape having a diameter of 5.0 μm. (Process (6D), FIG. 7 (d))

  Next, the electrode part 68 is formed. As the electrode portion 68, for example, an aluminum film having a thickness of 1.0 μm is formed by a sputtering method, and the aluminum film is processed into a predetermined shape using a known lithography and etching technique, thereby forming the electrode portion 68. (Step (6E), FIG. 8 (a))

  A photosensitive resist material is applied to the silicon substrate 81, and wet etching is performed using a photolithography technique to form the back chamber 71 and the back chamber side wall 72. Since wet etching is used, the side surface of the back chamber side wall 72 is processed into a shape having an inclination with respect to the diaphragm 83 along the crystal plane of the silicon substrate 81. (Step (6F), FIG. 8 (b))

  The second insulating layer 84 is wet-etched through the through hole 85c of the back plate film 85. Thereby, the air gap 64 and the spacer 66 are formed. (Step (6G), FIG. 8 (c))

  In a conventional MEMS microphone manufacturing process, wet etching using an alkaline solution such as TMAH (Tetramethyl ammonium hydroxide) is performed when a silicon substrate is etched to form a back chamber. (Patent Document 1) Further, in order to chip a wafer on which a conventional MEMS microphone is formed, a technique using laser light called stealth dicing, which is different from blade dicing which has been widely used conventionally, is used (patent 1). Reference 2).

JP-T-2004-506394 JP 2004-235626 A

  However, in the anisotropic wet etching technique, since the etching rate varies depending on the crystal plane orientation, the etched portion becomes a plane having an angle along the crystal plane. For example, when a silicon substrate having a crystal orientation (100) plane is used, the etching rate of the (111) plane having an angle of about 55 degrees is very slow. Therefore, the thickness of the silicon substrate is set to 400 μm, for example, and the opening just below the diaphragm film is used. When the dimension is 1000 μm, the maximum opening dimension at the lower end of the back chamber is about 1570 μm, which is larger than the opening dimension directly below the diaphragm film. Therefore, it is difficult to reduce the size of the MEMS microphone chip using the wet etching technique.

  In order to solve the problem of the crystal plane orientation dependency of the wet etching technique, it is conceivable to process the side surface of the opening perpendicular to the silicon substrate by using a reactive ion etching technique capable of deep drilling. FIG. 9 shows an example of a MEMS microphone formed by processing the side surface of the opening perpendicular to the silicon substrate using the reactive ion etching technique. However, when the reactive ion etching technique is used, in addition to an increase in equipment cost, there is a possibility that the throughput may be reduced due to the branch and leaf method, resulting in an increase in cost as a whole.

  In addition, the MEMS microphone has a structure that is very fragile. Therefore, when the MEMS microphone is made into a chip by using blade dicing which is conventionally used when making a silicon semiconductor into chips, in order to prevent the MEMS microphone from being broken, cutting waste generated by blade dicing is generated. It is necessary to control the amount of water used to discharge the water. However, when the amount of water is suppressed, cutting waste remains in the chip-shaped MEMS microphone, and the throughput is reduced. In order to solve this problem, stealth dicing using laser light has been developed instead of blade dicing. However, in stealth dicing, the equipment cost becomes very expensive, and there is a problem that the cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a MEMS microphone that can be miniaturized at a low cost without using an expensive etching processing apparatus and a method for manufacturing the same.
Another object of the present invention is to solve the above-described problems and provide a MEMS microphone with a high yield and a manufacturing method thereof at a low cost without using an expensive dicing apparatus.

In order to solve the above problems, a MEMS microphone according to the present invention has a fixed electrode provided with a plurality of through-holes through which sound waves pass, and is opposed to the fixed electrode partially through a spacer formed by an insulating layer. An air gap is formed, a capacitor is formed between the air gap and the fixed electrode, and a vibration electrode for changing the capacitance of the capacitor by receiving the sound wave and vibrating, the fixed electrode, and the vibration An electrode part for connecting an electrode to the outside, an electrode part supporting the electrode part and the vibration electrode, and an opening serving as a back chamber at a position facing the air gap, and a side surface of the opening on the vibration electrode And a support substrate which is perpendicular to the substrate and formed of an insulating layer.

  The method for manufacturing a MEMS microphone according to the present invention is a method for manufacturing a MEMS microphone, in which a first insulating layer is formed on the surface of a silicon substrate (A), and a vibrating electrode is formed on the first insulating layer. A step (B) of forming a diaphragm film having, a step (C) of forming a second insulating layer on the first insulating layer and the diaphragm film, and a through hole on the second insulating layer. A step (D) of forming a back plate film having a fixed electrode, a metal film is deposited, an electrode portion connected to the vibration electrode and the fixed electrode is formed, and a chip is formed between the chips to form a MEMS microphone. Removing the metal film, the back plate film, and the second insulating layer deposited on the street portion provided in the substrate, and exposing the first insulating layer on the surface of the silicon substrate E), a step (F) of attaching a temporary support base material with an adhesive material on the back plate film and the electrode part, and the silicon substrate was entirely removed by etching to form a surface of the silicon substrate. A step (G) of exposing the first insulating layer; and a third insulating layer is formed on the exposed surface of the first insulating layer, and is located at a position corresponding to the vibration electrode with the first insulating layer interposed therebetween. Removing the third insulating layer to form a back chamber and a layer serving as a back chamber side wall (H), removing the temporary support substrate (I), and through the through hole of the back plate film And a step (J) of removing a part of the second insulating layer by etching to form an air gap and a spacer.

  In the MEMS microphone manufacturing method of the present invention, in the step (H), a third insulating layer is formed on the exposed back surface of the first insulating layer, and the position corresponding to the vibrating electrode with the first insulating layer interposed therebetween. Removing the third insulating layer at the same time and removing the third insulating layer at the street portion to form a back chamber and a back chamber side wall (H1); And a step (H2) of attaching the temporary support base material.

  According to the present invention, since the side surface of the back chamber can be processed perpendicularly to the diaphragm film without using an expensive etching processing apparatus, a MEMS microphone that can be reduced in cost and a method for manufacturing the same can be manufactured. Can be provided.

  In addition, according to the present invention, since the MEMS microphone can be reduced in size, the number of MEMS microphones that can be manufactured from one wafer can be increased, and a MEMS microphone that can reduce costs and a manufacturing method thereof are provided. Can do.

  Further, according to the present invention, since the completed MEMS microphone does not include a silicon substrate, it is possible to provide a MEMS microphone capable of reducing the capacity and a method for manufacturing the same.

  Furthermore, according to the present invention, since the MEMS microphone can be formed into a chip without using an expensive dicing apparatus, it is possible to provide a low-cost MEMS microphone with a high yield and a method for manufacturing the same.

It is sectional drawing which shows embodiment of the semiconductor device which concerns on this invention. It is sectional drawing which shows 1st Embodiment of the manufacturing method of the semiconductor device which concerns on this invention. It is sectional drawing which shows 1st Embodiment of the manufacturing method of the semiconductor device which concerns on this invention. It is sectional drawing which shows 1st Embodiment of the manufacturing method of the semiconductor device which concerns on this invention. It is sectional drawing which shows 2nd Embodiment of the manufacturing method of the semiconductor device which concerns on this invention. It is sectional drawing which shows one example of the semiconductor device which concerns on a prior art. It is sectional drawing which shows one example of the manufacturing method of the semiconductor device which concerns on a prior art. It is sectional drawing which shows one example of the manufacturing method of the semiconductor device which concerns on a prior art. It is sectional drawing which shows another example of the semiconductor device which concerns on a prior art.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, the same referential mark is attached | subjected to the same component and description is abbreviate | omitted. FIG. 1 is a diagram showing an embodiment of a MEMS microphone according to the present invention. An embodiment of a MEMS microphone according to the present invention will be described with reference to FIG.

  The MEMS microphone 1 according to the embodiment of the present invention includes a first insulating layer 22a, a diaphragm film 23 provided on one surface of the first insulating layer 22a and having a vibrating electrode 3 that vibrates by sound pressure, and a sound wave passes therethrough. A back plate film 25 having a fixed electrode 5 that includes a plurality of through-holes 25c that are opposed to the vibration electrode 3 through the air gap 4 to form a capacitor, and an air gap 6 that makes the vibration electrode 3 and the fixed electrode 5 face each other. An inner portion, a spacer 6 having an outer side surface formed by etching, maintaining an interval between the diaphragm film 23 and the back plate film 25, and electrode portions connected to the vibrating electrode 3 and the fixed electrode 5 respectively. 8 and the surface of the first insulating layer 22a opposite to the surface on which the diaphragm film 23 is disposed. Has an opening for forming the bar 11, having a back chamber side wall 12 is substantially perpendicular to the side surface of the opening is the diaphragm membrane 23. Embodiments of the semiconductor device according to the present invention will be described in more detail in the following first and second embodiments of the method for manufacturing a semiconductor device according to the present invention.

  2-4 is sectional drawing which shows 1st Embodiment of the manufacturing method of the MEMS microphone based on this invention. A first embodiment of the MEMS microphone manufacturing method according to the present invention will be described below with reference to FIGS.

  A silicon substrate 21 is prepared. For example, a silicon substrate 21 having a crystal orientation (100) plane and a thickness of 400 μm is used. Then, the first insulating layer 22 a is formed on the surface of the silicon substrate 21. At this time, according to the thermal oxidation method, the first insulating layer 22b is also formed on the back surface. As the first insulating layer, for example, a thermal oxide film having a thickness of 0.2 μm is formed by thermal oxidation. (Step (1A), FIG. 2 (a))

  A diaphragm film 23 is formed on the first insulating layer 22a formed on the surface of the silicon substrate 21 and processed into a predetermined shape. As the diaphragm film 23, for example, a 0.1 μm silicon nitride film and a 1.0 μm polysilicon film constituting the vibrating electrode are stacked and deposited using a CVD (Chemical Vapor Deposition) apparatus. Then, the laminated diaphragm film 23 is processed into a predetermined shape using known lithography and etching techniques. Here, the predetermined shape of the diaphragm film 23 is, for example, a circular shape having a diameter of 1040 μm. (Step (1B), FIG. 2 (b))

  A second insulating layer 24 is formed on the first insulating layer 22a and the diaphragm film 23 formed on the first insulating layer 22a. As the second insulating layer 24, for example, an NSG (Non-doped Silicate Glass) film having a film thickness of 3 μm is deposited. (Step (1C), FIG. 2 (c))

  A film to be the back plate film 25 is formed on the second insulating layer 24. As a film to be the back plate film 25, for example, a 1 μm thick polysilicon film 25a and a 0.2 μm thick silicon nitride film 25b constituting a fixed electrode are deposited, and known lithography and etching are performed on the upper surface of the diaphragm film 23. The back plate film 25 is formed by processing the polysilicon film 25a and the silicon nitride film 25b into a predetermined size using a technique. The size of the back plate film 25 is, for example, a circular shape having a diameter of 1 mm smaller than the diaphragm film 23. The back plate film 25 is formed with a plurality of through-holes 25 c that communicate the front and back of the back plate film 25 so as not to disturb the vibration of the diaphragm film 23. The size of the through hole 25c is, for example, a circular shape having a diameter of 5.0 μm. (Step (1D), FIG. 2 (d))

  Next, a metal film is formed, and the formed metal film is processed to form electrode portions 8 connected to the vibrating electrode 3 and the fixed electrode 5 respectively. For example, an aluminum film having a thickness of 1.0 μm is formed by a sputtering method, and the aluminum film is processed into a predetermined shape using a known lithography and etching technique, thereby forming the electrode portion 8. At this time, if the second insulating layer 24 is removed and the first insulating layer 22a is exposed in the street portion 28 provided between the chips of the MEMS microphone, it is preferable for the individualization described later. It is. (Step (1E), FIG. 3 (a))

  An adhesive material 31 resistant to an alkaline solution is applied to the front side of the silicon substrate 21 on which the MEMS device is formed, and a temporary support base material 32 is attached. Here, for example, an acrylic adhesive material is used for the adhesive material 31, and a glass plate formed of non-alkali glass is used for the temporary support base material 32. (Step (1F), FIG. 3 (b))

  The first insulating layer 22b on the back side of the silicon substrate 21 is removed. Then, for example, all of the silicon substrate 21 is removed by wet etching using an alkaline solution such as TMAH (Tetramethyl ammonium hydroxide), and the first insulating layer 22a formed on the front side of the silicon substrate 21 is exposed. (Step (1G), FIG. 3 (c))

  A third insulating layer 33 is formed on the exposed surface of the first insulating layer 22a. For example, the third insulating layer 33 may be formed by applying a photosensitive resin material that is a permanent resist material. At this time, the photosensitive resin material is processed using a photolithography technique to form the back chamber 11 and the structural material 33 serving as the back chamber side wall. This structural member 33 can be used as a back chamber side wall of the MEMS microphone for a semi-permanent period. The opening of the back chamber 11 is formed in a cylindrical shape having a diameter of 1 mm and a depth of 200 μm, for example. Further, as a resist material that can be used semipermanently for a long time, for example, TMMR-2000 manufactured by Tokyo Ohka Kogyo is used. (Step (1H), FIG. 4 (a))

  Here, the back chamber and the back chamber side wall may be formed by, for example, discharging a material such as an epoxy resin into a dispensing method or an ink jet method. Further, a back chamber may be formed by processing a substrate such as resin or glass into a shape of a back chamber in advance and bonding them using a bonding technique. The back chamber may be formed by processing into a chamber shape and bonding using a bonding technique. Alternatively, a back chamber may be formed by applying a photosensitive resin or the like and pressing a mold using a nanoimprint technique. (Step (1H), FIG. 4 (a))

  By forming a back chamber by processing a substrate such as resin or glass instead of wet etching the silicon substrate, the back chamber is made finer because it is not restricted by the processing angle dependence associated with the crystal properties of silicon. Can be formed. (Step (1H), FIG. 4 (a))

  The temporary support base material 32 on which the vibrating electrode 3 and the fixed electrode 5 of the MEMS microphone are formed is immersed in a solution in which the adhesive resin 31 is dissolved, and the temporary support base material 32 is removed. Here, PGMEA (propylene glycol monomethyl ether acetate) is used for the solution. (Step (1I), FIG. 4 (b))

  The second insulating layer 24 is wet etched through the through hole 25c in the back plate film, and the portion removed by the etching is processed into an air gap 4 provided between the back plate film and the diaphragm film. Further, the portion left by the etching is processed into the spacer 6 that supports the back plate film. For the etching, for example, a mixed acid aqueous solution of ammonium fluoride and acetic acid is used. By these processes, a MEMS microphone is formed. Here, the first insulating layer 22a exposed to the street portion 28 is also removed. (Step (1J), FIG. 4 (c))

  Thereafter, only the structure 33 is separated into pieces using a dicing blade. The structure 33 is made of a photosensitive resin material, and can be separated into pieces with a higher yield than cutting of a silicon semiconductor.

  Next, a second embodiment of the MEMS microphone manufacturing method according to the present invention will be described. Regarding the second embodiment of the MEMS microphone manufacturing method according to the present invention, the steps (2A) to (2G) are the steps (1A) to (1G) of the first embodiment of the MEMS microphone manufacturing method according to the present invention. ), The description thereof will be omitted, and the steps after step (2H) will be described. FIG. 5 is a diagram showing a step (2H) and subsequent steps of the second embodiment of the method for manufacturing the MEMS microphone according to the present invention. Based on FIG. 5, the process (2H) and subsequent steps of the second embodiment of the MEMS microphone manufacturing method according to the present invention will be described.

  Similar to the step (1H) of the first embodiment of the method for manufacturing the MEMS microphone according to the present invention, the third insulating layer 33 is formed on the exposed back surface of the first insulating layer 22a. For example, the third insulating layer 33 may be formed by applying a photosensitive resin material that is a resist material that can be used semipermanently for a long period of time. At this time, the photosensitive resin material is processed using a photolithography technique to form the back chamber 11 and the back chamber side wall 12. The back chamber side wall 12 can be used as a back chamber side wall of the MEMS microphone for a semi-permanent period. The opening of the back chamber 11 is formed in a cylindrical shape having a diameter of 1000 μm and a depth of 200 μm, for example. As a resist material that can be used semipermanently for a long period of time, for example, TMMR-2000 manufactured by Tokyo Ohka Kogyo is used.

  Here, the back chamber 11 and the back chamber side wall 12 may be formed, for example, by discharging a material such as an epoxy resin in a dispense method or an inkjet method. Further, a back chamber may be formed by processing a substrate such as resin or glass into a shape of a back chamber in advance and bonding them using a bonding technique. The back chamber may be formed by processing into a chamber shape and bonding using a bonding technique. Alternatively, a back chamber may be formed by applying a photosensitive resin or the like and pressing a mold using a nanoimprint technique.

  By forming a back chamber by processing a substrate such as resin or glass instead of wet etching the silicon substrate, the back chamber is made finer because it is not restricted by the processing angle dependence associated with the crystal properties of silicon. Can be formed.

  In the step (2H) of the second embodiment of the MEMS microphone manufacturing method according to the present invention, there is no material constituting the back chamber side wall 12 in the street portion 29 between the chips in order to chip the MEMS microphone. In addition, an opening is formed in the street portion 29 between the chips. (Step (2H), FIG. 5 (a))

  The second temporary support substrate 34 is attached to the back chamber side wall 12 of the MEMS microphone. The second temporary support substrate 34 may be an adhesive tape that can be peeled off by, for example, ultraviolet (UV) irradiation. (Step (2I), FIG. 5 (b))

  The temporary support substrate 32 on which the MEMS microphone is formed is immersed in a solution in which the adhesive resin 31 is dissolved, and the first (?) Temporary support substrate 32 is removed. Here, PGMEA (propylene glycol monomethyl ether acetate) is used for the solution. In the step of removing the temporary support base material 32, the device layer of the MEMS microphone, the back chamber side wall 12, and the second temporary support base material 34 are prevented from peeling off. (Process (2J), FIG. 5 (c))

  The second insulating layer 24 is etched through the through hole 25c of the back plate film, and a portion removed by the etching is processed into an air gap 4 provided between the back plate film and the diaphragm film. Further, the portion left after the etching is processed into the spacer 6 that supports the back plate film. At this time, the second insulating layer 24 and the first insulating layer 22a in the street portion 28 of the MEMS microphone are also removed. As a result, the MEMS microphone can be chipped without using the stealth dicing technique. By these processes, a MEMS microphone is formed. For the etching, for example, a mixed acid aqueous solution of ammonium fluoride and acetic acid is used. By these processes, a MEMS microphone is formed. (Process (2K), FIG. 5 (d))

1: MEMS microphone, 3: vibrating electrode, 4: air gap, 5: fixed electrode, 6: spacer, 8: electrode part, 11: back chamber, 12: back chamber side wall, 21: silicon substrate, 22a: first insulation Layer (front), 22b: first insulating layer (back), 23: diaphragm film, 24: second insulating layer, 25: backplate film, 25a: polysilicon film, 25b: silicon nitride film, 25c: through-hole, 28: Street portion, 29: Street portion, 31: Adhesive material, 32: First temporary support substrate, 33: Structural material, 34: Second temporary support substrate, 61: Conventional MEMS microphone, 63: Vibration Electrode, 64: Air gap, 65: Fixed electrode, 66: Spacer, 68: Electrode part, 71: Back chamber, 72: Back chamber side wall, 81: Silicon substrate, 82: 1 insulating layer, 83: diaphragm film, 84: second insulating layer, 85: back plate film, 85a: polysilicon film, 85b: silicon nitride film, 85c: through-hole, 90: conventional MEMS microphone, 91: back chamber , 92: Back chamber side wall

Claims (3)

A fixed electrode having a plurality of through holes for sound waves to pass through;
An air gap is formed to face the fixed electrode partially through a spacer formed by an insulating layer, a capacitor is formed between the fixed electrode and the air gap, and the sound wave is received and vibrated. And a vibrating electrode for changing the capacitance of the capacitor,
An electrode portion for connecting the fixed electrode and the vibrating electrode to the outside;
The electrode unit and the vibration electrode are supported, and an opening serving as a back chamber is provided at a position facing the air gap. A side surface of the opening is perpendicular to the vibration electrode and is formed by an insulating layer. A MEMS microphone comprising a supporting substrate. A method of manufacturing a MEMS microphone, comprising:
A step (A) of forming a first insulating layer on the surface of the silicon substrate;
Forming a diaphragm film having a vibrating electrode on the first insulating layer (B);
Forming a second insulating layer on the first insulating layer and the diaphragm film (C);
Forming a back plate film having a through hole and a fixed electrode on the second insulating layer (D);
A metal film is deposited to form an electrode portion connected to the vibration electrode and the fixed electrode, and the metal film deposited on a street portion provided between the chips to form a MEMS microphone as a chip, the back Removing the plate film and the second insulating layer and exposing the first insulating layer on the surface of the silicon substrate;
A step (F) of attaching a temporary support base material with an adhesive material on the back plate film and the electrode portion;
Removing all the silicon substrate by etching and exposing the first insulating layer formed on the surface of the silicon substrate;
A third insulating layer is formed on the exposed surface of the first insulating layer, and the third insulating layer at a position corresponding to the vibrating electrode is removed with the first insulating layer interposed therebetween, and a back chamber and a back surface are removed. Forming a layer to be a chamber sidewall (H);
Removing the temporary support substrate (I);
A step (J) of removing a part of the second insulating layer by etching from the through hole of the back plate film to form an air gap and a spacer;
A method of manufacturing a MEMS microphone, comprising: Step (H)
A third insulating layer is formed on the exposed surface of the first insulating layer, and the third insulating layer located at a position corresponding to the vibrating electrode is removed with the first insulating layer interposed therebetween, and the street portion is formed. Removing the third insulating layer to form a back chamber and a back chamber sidewall (H1);
A step (H2) of attaching a second temporary support substrate to the back chamber side wall;
A method for manufacturing a MEMS microphone according to claim 2, comprising:

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