JP4737720B2 - Diaphragm, manufacturing method thereof, condenser microphone having the diaphragm, and manufacturing method thereof - Google Patents

Description

  The present invention relates to a diaphragm, a manufacturing method thereof, a condenser microphone having the diaphragm, and a manufacturing method thereof.

  A capacitor microphone and an acceleration sensor that can be manufactured by applying a manufacturing process of a semiconductor device are known. The condenser microphone has electrodes on each of a diaphragm and a plate that are vibrated by sound waves, and the plate and the diaphragm are supported in a state of being separated from each other by a support portion. The condenser microphone converts the capacitance change due to the displacement of the diaphragm into an electric signal and outputs it.

  Patent Document 1 discloses a condenser microphone having a bent portion between a center portion and an end portion of a diaphragm. In the condenser microphone described in Patent Document 1, the diaphragm's residual stress is relieved by deformation of the bent portion, thereby increasing the diaphragm's amplitude and increasing the sensitivity. However, the bent portion of the diaphragm described in Patent Document 1 is formed of a single thin film. In general, the bent portion of such a diaphragm is formed by deposition on the surface of the stepped portion formed in the sacrificial layer, so that the film thickness becomes thinner as it approaches the bottom surface of the stepped portion, and on the side surface of the stepped portion of the sacrificial layer. A crystal grain boundary is formed between the portion that grows on the bottom and the portion that grows on the bottom surface of the step. In other words, the strength of the diaphragm decreases as the level difference of the bent portion is increased. Therefore, in the condenser microphone described in Patent Document 1, the sensitivity cannot be increased by increasing the step of the bent portion while maintaining the strength of the diaphragm.

JP 2001-231099 A

  The present invention has been made to solve the above-described problems, and provides a diaphragm having a bent portion having a high strength and a manufacturing method thereof, a condenser microphone having a high sensitivity and a high diaphragm strength, and a manufacturing method thereof. With the goal.

(1) A method of manufacturing a diaphragm for achieving the above object includes forming a central portion of the diaphragm by patterning the first film, and forming a second film on the proximal end portion of the first film by deposition. Forming a third film on the second film by deposition, and patterning the third film into a shape extending from the second film to the outside of the first film, Forming a bent portion of the diaphragm, which is formed of a multilayer film including the first film, the second film, and the third film, and extends while bending from the central portion to the outside of the central portion. Including.
By forming a second film on the proximal end portion of the first film constituting the center of the diaphragm and forming a third film extending from the second film to the outside of the first film, The bent portion can be formed outside the central portion of the diaphragm without bending the third film from the first film. Therefore, no crystal grain boundary is formed at the bent portion of the diaphragm. Moreover, the level | step difference of the bending part which consists of a multilayer film containing a 3rd film | membrane from a 1st film | membrane can be controlled by the film thickness of a 2nd film | membrane, for example. That is, it is possible to form a required bent portion on the outside of the center portion of the diaphragm while maintaining the strength of the diaphragm. Here, “strength” indicates resistance to destruction of the structure. High strength means that the structure is not easily broken by external force, and low strength means that the structure is easily broken by external force. The near end means a portion close to the end.

(2) A method of manufacturing a condenser microphone for achieving the above object includes a plate having a fixed electrode, a central portion having a movable electrode, and a bent portion extending outwardly while being bent from the central portion. A method of manufacturing a condenser microphone, comprising: a vibrating diaphragm; and a support portion that supports the plate and an outer side of the bent portion of the diaphragm while forming a gap between the fixed electrode and the movable electrode. The central portion of the diaphragm is formed by patterning the first film, the second film is formed by deposition on the proximal end of the first film, and the second film is formed on the second film. Three films are formed by deposition, and the third film is patterned into a shape extending from the second film to the outside of the first film, whereby the first film and the second film are patterned. Consisting multilayer film containing the membrane third film, to form the bent portion of the diaphragm includes.
It is required by forming a second film on the proximal end of the first film constituting the center of the diaphragm and forming a third film extending from the second film to the outside of the first film. A high-strength diaphragm having a bent portion with a level difference can be formed. In this way, the bent portion formed between the end fixed to the diaphragm support and the central portion is deformed by the residual stress in the central portion of the diaphragm to relieve the residual stress in the central portion of the diaphragm. The amplitude of the vibration caused by the sound wave at the center is increased by being greatly deformed by the sound wave. That is, it is possible to manufacture a condenser microphone with high sensitivity and high diaphragm strength.

(3) A method of manufacturing a condenser microphone for achieving the above object may include forming the plate by patterning the third film.
Since the third film constituting the plate and the third film constituting the bent portion of the diaphragm can be formed in the same process, the manufacturing process of the condenser microphone can be simplified.

(4) A diaphragm for achieving the above object includes a central part, a first film constituting the central part, and a second film formed on a near end part of the first film, A multi-layer film including a third film extending from the second film to the outside of the first film, and a bent portion extending while bending from the central portion to the outside of the central portion.

(5) A condenser microphone for achieving the above object includes a plate having a fixed electrode, a central part having a movable electrode, a first film constituting the central part, and a near end part of the first film. And a bent portion extending outwardly while being bent from the center portion, comprising a second film formed on the second film and a third film extending from the second film to the outside of the first film. A diaphragm that vibrates by sound waves, and a support part that supports the plate and the outer side of the bent part of the diaphragm while forming a gap between the fixed electrode and the movable electrode, Is provided.
The diaphragm has a bent portion and is supported by the support portion outside the bent portion. In the condenser microphone having such a structure, the bending portion of the diaphragm is deformed by the residual stress in the central portion to relieve the residual stress in the central portion of the diaphragm, or the bending portion of the diaphragm is greatly deformed by the sound wave, thereby The amplitude by the sound wave of the part can be increased. Further, since the bent portion of the diaphragm is formed of a multilayer film, no crystal grain boundary is formed in the bent portion, and the strength of the bent portion is high. That is, the condenser microphone according to the present invention has high sensitivity and high diaphragm strength.

In the present specification, “... formed on” means “... formed directly on” and “... on the intermediate” unless there is a technical impediment. It is meant to include both “formed through”.
Further, the order of the steps of the manufacturing method described in the claims is not limited to the order of description unless there is a technical impediment, and may be performed in any order, or performed simultaneously. May be.

Embodiments of the present invention will be described below based on a plurality of examples. In each of the embodiments, the component having the same reference sign corresponds to the component of the other embodiment having the reference sign.
(First Example)
1 and 2 are schematic views showing the configuration of a condenser microphone according to a first embodiment of the present invention. 2 is a plan view of the condenser microphone according to the first embodiment of the present invention, FIG. 1A is a sectional view taken along line A1-A1 of FIG. 2, and FIG. 1B is B1-B1 of FIG. It is sectional drawing by a line. The condenser microphone 1 according to the first embodiment of the present invention is a so-called silicon microphone manufactured using a semiconductor manufacturing process. The condenser microphone 1 includes a sound sensing part depicted as a cross-sectional view in FIGS. 1A and 1B and a detection part depicted as a circuit diagram in FIG. Hereinafter, the configuration of the sound sensing unit, the configuration of the detection unit, and the manufacturing method of the condenser microphone 1 will be described in this order.

(Configuration of sound sensor)
As shown in FIG. 1, the sound sensing part of the condenser microphone 1 includes a diaphragm 10, a back plate 30, a support part 40, and the like.
Diaphragm 10 is supported by support portion 40 in the form of a double-supported beam (see FIG. 2). The central portion 12 of the diaphragm 10 is formed by a portion that is not fixed to the insulating film 131 of the conductive film 121, and the outer bent portion 14 is a portion that is fixed to the insulating film 131 of the conductive film 121 and the conductive film 122. A portion which is not fixed to the insulating film 111 and a multilayer film of the insulating film 131, the insulating film 132, and the conductive film 142 are formed (see FIG. 1B). The conductive film 121 constituting the central portion 12 of the diaphragm 10 functions as a movable electrode. The conductive film 121, the conductive film 122, and the conductive film 142 are semiconductor films such as polycrystalline silicon (hereinafter referred to as polysilicon). The insulating film 131 and the insulating film 132 are oxide films such as SiO ₂ . The conductive film 121 and the conductive film 122 correspond to the “first film” recited in the claims, the insulating film 131 and the insulating film 132 correspond to the “second film”, and the conductive film 142 corresponds to the “third film”. Is equivalent to.

  The first film to the third film have been described as being composed of a single layer film, but the first film to the third film may be each a multilayer film. Moreover, you may comprise the center part 12 of the diaphragm 10 by the insulating film and the electrically conductive film as a movable electrode formed in the center part at least. Further, although the bent portion 14 having the step portion formed by the insulating film 131 and the step portion formed by the insulating film 132 is illustrated, the bent portion only needs to have at least one step portion. Further, the insulating film may not have the same shape as the conductive film.

  The back plate 30 as a plate is formed of a portion of the conductive film 141 that is not fixed to the insulating film 133 (see FIG. 1A). The conductive film 141 is a semiconductor film such as polysilicon. The back plate 30 is supported by the support portion 40 in a doubly supported beam shape and intersects the central portion 12 of the diaphragm 10 three-dimensionally. Thus, by making the back plate 30 face only the central portion 12 that is largely displaced by the sound wave of the diaphragm 10, the back plate 30 is not changed by the sound wave of a capacitor (hereinafter referred to as a microphone capacitor) formed by the diaphragm 10 and the back plate 30. Capacitance components can be reduced. A plurality of through holes 32 are formed in the back plate 30 (see FIG. 2). As a result, the sound wave from the sound source passes through the through hole 32 and propagates to the diaphragm 10. The conductive back plate 30 functions as a fixed electrode.

The support portion 40 includes a portion fixed to the insulating film 133 of the conductive film 141, a portion fixed to the insulating film 111 and the insulating film 133 of the conductive film 122, the insulating film 133, the conductive film 123, and the insulating film 111. And the substrate 100. The insulating film 111 and the insulating film 133 are oxide films such as SiO ₂ , the conductive film 123 is a semiconductor film such as polysilicon, and the substrate 100 is a single crystal silicon substrate, for example. An opening 42 that penetrates the substrate 100 and the insulating film 111 is formed in the support portion 40. The opening 42 constitutes a back cavity of the condenser microphone 1.

  The electrode 60 shown in FIG. 2 is an electrode for connecting the diaphragm 10 and the detection unit. The electrode 60 is formed in the same layer as the conductive film 122 and is connected to the conductive film 121 through a conductive wire 125 extending from the electrode 60 to the conductive film 122, a conductive film 122, and a conductive wire 124 extending from the conductive film 122 to the conductive film 121. (See FIG. 4 (A2)). The electrode 61 is an electrode for connecting the back plate 30 and the detection unit. The electrode 61 is connected to the conductive film 141 through a conductive wire 143 extending from the electrode 61 to the conductive film 141.

  The electrode 62 is connected to the conductive film 123 through a conductive wire 126 extending from the electrode 62 to the conductive film 123 (see FIG. 4A2). The conductive film 123 is electrically insulated from other conductive films and is formed between the conductive film 141 constituting the back plate 30 and the substrate 100. By applying the same voltage as the output voltage of the detection unit to the electrode 62, the conductive film 123 can be used as a guard electrode. Details will be described later.

  The condenser microphone 1 may be configured such that the diaphragm 10 is positioned closer to the sound source than the back plate 30 and the sound wave directly propagates to the diaphragm 10. In this case, the through hole 32 of the back plate 30 functions as a passage that allows the gap 50 formed between the diaphragm 10 and the back plate 30 to communicate with the back cavity.

(Configuration of detector)
As shown in FIG. 1A, the diaphragm 10 is connected to a bias power supply circuit 1000, and the back plate 30 is connected to the ground via a resistor 1002. The back plate 30 is also connected to the preamplifier 1010. The detection unit of the condenser microphone 1 outputs a signal correlated with the voltage between the back plate 30 and the ground from the preamplifier 1010.

  Specifically, for example, the lead wire 1004 connected to the output end of the bias power supply circuit 1000 is connected to the electrode 60 and the substrate 100, and the lead wire 1006 connected to one end of the resistor 1002 is connected to the electrode 61. The lead wire 1008 connected to the other end of the resistor 1002 is connected to the ground of the mounting board of the condenser microphone 1. A resistor having a large resistance value is used as the resistor 1002. Specifically, it is desirable that the resistor 1002 has a G-order electrical resistance. A lead wire 1006 connecting the back plate 30 and the resistor 1002 is also connected to the input terminal of the preamplifier 1010. It is desirable to use a preamplifier 1010 having a high input impedance.

  As described above, the conductive film 123 can be used as a guard electrode by applying the same voltage as the output voltage of the detection unit to the electrode 62. The guard electrode is an electrode for reducing parasitic capacitance generated between the conductive film 141 constituting the back plate 30 and the substrate 100. Specifically, for example, when the conductive film 123 is used as a guard electrode, a voltage follower circuit may be formed using the preamplifier 1010 illustrated in FIG. 1A and the output terminal of the preamplifier 1010 may be connected to the electrode 62. By setting the conductive film 141 and the conductive film 123 included in the back plate 30 to have the same potential, parasitic capacitance generated between the conductive film 141 and the conductive film 123 can be removed. Can be reduced.

(Condenser microphone operation)
When the sound wave passes through the through hole 32 of the back plate 30 and propagates to the diaphragm 10, the diaphragm 10 is vibrated by the sound wave. When diaphragm 10 vibrates, the distance between back plate 30 and diaphragm 10 changes due to the vibration, and the capacitance of the microphone capacitor formed by diaphragm 10 and back plate 30 changes.

  Since the back plate 30 is connected to the resistor 1002 having a large resistance value as described above, even if the capacitance of the microphone capacitor changes due to the vibration of the diaphragm 10, the charge accumulated in the microphone capacitor causes the resistor 1002 to There is almost no flow. That is, it can be considered that the electric charge accumulated in the microphone capacitor does not change. Therefore, a change in the capacitance of the microphone capacitor can be taken out as a change in the voltage between the back plate 30 and the ground.

  In this way, the condenser microphone 1 outputs an extremely slight change in the capacitance of the microphone condenser as an electrical signal. That is, the condenser microphone 1 converts a change in sound pressure applied to the diaphragm 10 into a change in capacitance of the microphone capacitor, and converts a change in capacitance of the microphone capacitor into a change in voltage, thereby changing the sound pressure. Output correlated electrical signals.

  As described above, the bent portion 14 of the diaphragm 10 extends while being bent from the central portion 12 to the support portion 40. As a result, the bending portion 14 is deformed by the residual stress of the central portion 12 to relieve the residual stress of the central portion 12, or the bending portion 14 is greatly deformed by the sound wave, whereby the amplitude of the vibration due to the sound wave of the central portion 12. Can be increased.

  However, when the diaphragm 10 is vibrated by sound waves, the stress accompanying the deformation of the diaphragm 10 is concentrated on the bent portion 14. Therefore, if the strength of the bent portion 14 of the diaphragm 10 is insufficient, the diaphragm 10 may be damaged at the bent portion 14.

  Therefore, in the condenser microphone 1, the bent portion 14 of the diaphragm 10 is formed of a multilayer film as described above. By configuring the bent portion 14 of the diaphragm 10 with a multilayer film, the bent portion 14 can be formed outside the central portion 12 of the diaphragm 10 without bending each thin film forming the bent portion 14. Therefore, no crystal grain boundary is formed at the bent portion 14 of the diaphragm 10. Further, the step of the bent portion 14 (see the arrow 90 shown in FIG. 3) can be controlled by the film thickness of the insulating film 131 and the insulating film 132 as the second film, for example. That is, by forming the bent portion 14 of the diaphragm 10 with a multilayer film, the bent portion 14 having the required step can be formed while maintaining the strength of the diaphragm 10.

(Condenser microphone manufacturing method)
4 to 6 are schematic views showing a method for manufacturing the condenser microphone 1. FIG. 4B is a cross-sectional view taken along line B4-B4 shown in FIG. 4A1, and FIG. 4C is a cross-sectional view taken along line C4-C4 shown in FIG.

First, the insulating film 110 is formed over the substrate 100 as illustrated in FIG. The substrate 100 is a semiconductor substrate such as a single crystal silicon substrate. Specifically, the insulating film 110 is formed on the substrate 100 by depositing an insulating material on the surface of the substrate 100 by, for example, CVD (Chemical Vapor Deposition).
Next, the conductive film 120 is formed over the insulating film 110 by CVD or the like. The conductive film 120 is, for example, a polysilicon film. Note that this step can be omitted by using an SOI substrate.

  Next, as shown in FIG. 4A2, the conductive film 120 is patterned to form the conductive film 123, the conductive wire 124, the conductive wire 125, the electrode 60, and the electrode 62 from the conductive film 121. The conductive film 121 and the conductive film 122 are substantially rectangular, and the longitudinal direction of the diaphragm 10 is such that the conductive film 121 constituting the central portion 12 of the diaphragm 10 is positioned between the two conductive films 122 constituting the bent portion 14. Is arranged. The conductive film 123 is formed in accordance with the shape and arrangement of the conductive film 141 in order to face the conductive film 141 formed in a process described later.

  Specifically, for example, the patterning of the conductive film 120 is performed as follows. First, a resist film that exposes unnecessary portions of the conductive film 120 is formed on the conductive film 120 by lithography. More specifically, a resist is applied to the conductive film 120 to form a resist film. Then, a mask having a predetermined shape is arranged, and the resist film is exposed and developed to remove unnecessary resist films. As a result, a resist film that exposes unnecessary portions of the conductive film 120 is formed on the conductive film 120. For removing the resist film, a resist stripping solution such as NMP (N-methyl-2-pyrrolidone) is used. Next, the conductive film 120 exposed from the resist film is etched by RIE (Reactive Ion Etching) or the like to form the conductive film 123 to the conductive film 123, the conductive wire 124, the conductive wire 125, and the electrode 60 to the electrode 62. Then, the resist film is removed.

Next, as illustrated in FIG. 4A3, an insulating film 130 thicker than the conductive film 120 is formed over the insulating film 110 by CVD or the like. In steps to be described later, the insulating film 110 and the insulating film 130 (hereinafter referred to as an insulating film) from the conductive film 121 to the conductive film 123, the conductive film 141, and the conductive film 142 (see FIG. 2, hereinafter referred to as a conductive film). In order to selectively remove the insulating film, the insulating film is formed using a material having a high selectivity with respect to the conductive film. For example, when the conductive film is formed of polysilicon, the insulating film may be formed of SiO ₂ . In the step of selectively removing the insulating film with respect to the conductive film, the insulating film 110 and the insulating film 130 are made of the same material in order to remove a part of the insulating film and leave the insulating film constituting the capacitor microphone 1. It is desirable to form. By forming the insulating film 110 and the insulating film 130 with the same material, the etching rates of both can be made equal. As a result, the etching amount of the insulating film can be easily controlled.

Next, a conductive film 140 is formed over the insulating film 130 by CVD or the like. For example, the conductive film 140 is a polysilicon film.
Next, as shown in FIG. 5 (B4), by patterning the conductive film 140, the conductive film 141 constituting the back plate 30, the conductive film 142 constituting the bent portion 14 of the diaphragm 10, the electrode 61, A conductive wire 143 is formed (see FIG. 5B4). The conductive film 141 is substantially rectangular, and the longitudinal direction thereof is orthogonal to the arrangement direction of the conductive films 121 and 122, and three-dimensionally intersects with the conductive film 121 through the insulating film 130. The conductive film 142 has a substantially rectangular shape, and extends from the near end portion 121 a adjacent to the conductive film 122 of the conductive film 121 to the near end portion 122 a adjacent to the conductive film 121 of the conductive film 122.

  Next, as shown in FIG. 5 (A5), an opening 102 that forms the opening 42 of the support portion 40 is formed in the substrate 100. Specifically, the opening 102 is formed, for example, as shown below. First, a resist film that exposes a portion of the substrate 100 where the opening 102 is to be formed is formed using lithography. Next, an opening 102 is formed in the substrate 100 by removing the portion exposed from the resist film of the substrate 100 with Deep RIE or the like until the insulating film 110 is reached. Then, the resist film is removed.

Next, parts of the capacitor microphone 1 are formed by removing a part of the insulating film 110 and the insulating film 130 (see FIGS. 6B7 and C7). Specifically, for example, a part of the insulating film 133 is removed as follows. First, as shown in FIGS. 6A6 to 6C6, a resist film 150 is formed on the insulating film 130 to cover a portion to be left as the support portion 40. Next, the insulating film is removed by wet etching. For example, when the insulating film 110 and the insulating film 130 are formed of SiO ₂ , hydrofluoric acid or the like may be used as an etchant.

  The etching solution enters the through hole 32, the through hole 144 formed in the conductive film 142, the conductive film 141, the gap between the conductive film 142 and the resist film 150, the opening portion 102 of the substrate 100, and the like, and the insulating film. Dissolve. For example, the etching solution dissolves the insulating film 130 between the conductive film 121 and the conductive film 141, thereby forming a gap 50 between the diaphragm 10 and the back plate 30, so that the insulating film resist film 150 and the substrate 100 are formed. The support part 40 is formed when the covered part remains.

  At this time, an etchant enters the gap between the conductive film 121 and the conductive film 122 and the through-hole 144 of the conductive film 142 to dissolve the insulating film 130, so that the insulating film 130 has a gap between the conductive film 142 and the conductive film 121. This part and the part between the conductive film 142 and the conductive film 122 of the insulating film 130 remain, whereby the insulating film 131 and the insulating film 132 as the second film are formed. Thus, by removing a part of the insulating film, each part of the condenser microphone 1 can be formed, and the sound sensing part of the condenser microphone 1 can be obtained.

(Second embodiment)
The detection part of the condenser microphone according to the second embodiment is substantially the same as the detection part of the condenser microphone 1 according to the first embodiment. Hereinafter, the sound sensor of the condenser microphone according to the second embodiment and the method for manufacturing the condenser microphone will be described in this order.

(Configuration of sound sensor)
FIG. 7 is a schematic diagram showing the configuration of the sound sensing unit of the condenser microphone according to the second embodiment of the present invention. 7A is a plan view, and FIG. 7B is a cross-sectional view taken along line B7-B7 in FIG. In the sound sensing part of the condenser microphone 2 according to the second embodiment, the diaphragm 210 and the back plate 230 are different from the diaphragm 10 and the back plate 30 according to the first embodiment.

  The diaphragm 210 is supported by the support portion 40 via a plurality of bent portions 214 extending outside the central portion 212. The central portion 212 of the diaphragm 210 has a disk shape, and the bent portion 214 extends to the support portion 40 while being bent in the radial direction of the central portion 212.

  Similar to the bent portion 14 according to the first embodiment, the bent portion 214 includes a portion fixed to the insulating film 131 of the conductive film 121, a portion not fixed to the insulating film 111 of the conductive film 122, and an insulating film. A multilayer film of 131, an insulating film 132, and a conductive film 142 is formed. Specifically, for example, the conductive film 121 has a disk shape, the conductive film 122 has an annular shape surrounding the conductive film 121, and the insulating film 131 and the insulating film 132 have a columnar shape. The insulating film 131 is located on the near end portion of the conductive film 121, and the insulating film 132 is located on the near end portion on the inner peripheral side of the conductive film 122.

  The back plate 230 is different from the back plate 30 according to the first embodiment in its two-dimensional shape. Specifically, for example, the central portion of the back plate 230 has a disk shape, and its proximal end portion extends radially from the central portion to the support portion. The film configuration of the back plate 230 is substantially the same as that of the back plate 30 according to the first embodiment.

(Condenser microphone manufacturing method)
8 to 10 are schematic views showing a method for manufacturing the condenser microphone 2. FIG. 8B is a cross-sectional view taken along line B8-B8 shown in FIG. 8A1 of FIG. 8A, and FIG. 8C is a cross-sectional view taken along line C8-C8 shown in FIG.

First, as shown in FIG. 8C 1, the insulating film 110 is formed on the substrate 100 and the conductive film 120 is formed on the insulating film 110 in the same manner as the manufacturing method according to the first embodiment.
Next, as illustrated in FIG. 8A2, the conductive film 120 is patterned to form the conductive film 121, the conductive film 122, the conductive wire 124, the conductive wire 125, and the electrode 60. The conductive film 121 has a disc shape, the conductive film 122 has an annular shape surrounding the conductive film 121, the conductive line 124 extends from the conductive film 121 to the conductive film 122, and the conductive line 125 extends from the conductive film 122 to the electrode 60.

Next, as shown in FIG. 9C3, the insulating film 130 is formed on the insulating film 110 and the conductive film 140 is formed on the insulating film 130 in the same manner as the manufacturing method according to the first embodiment.
Next, as shown in FIG. 9A4, the conductive film 140 is patterned to form a conductive film 141 that forms the back plate 230 and a plurality of conductive films 142 that form the bent portions 214 of the diaphragm 210. To do. The conductive film 141 has a disk shape at the center, and the proximal end extends radially from the center. The conductive film 142 extends from the near end portion 121 a of the conductive film 121 to the near end portion 122 a on the inner peripheral side of the conductive film 122.

  Next, as shown in FIG. 10A5, an opening 102 constituting the opening 42 of the support portion 40 is formed in the substrate 100 in the same manner as in the manufacturing method according to the first embodiment. Then, as shown in FIG. 10A6, parts of the capacitor microphone 2 are formed by removing a part of the insulating film 110 and the insulating film 130 in the same manner as in the manufacturing method according to the first embodiment.

  In the above, the diaphragm of the present invention, the manufacturing method thereof, the condenser microphone having the diaphragm, and the manufacturing method of the same have been described by exemplifying the condenser microphone 1 and the condenser microphone 2. However, the present invention can be applied to a diaphragm having a bent portion and a condenser microphone including such a diaphragm as long as there is no technical obstruction factor. The diaphragm and the manufacturing method thereof according to the present invention may be applied to a diaphragm of a sensor that detects pressure other than sound pressure.

  Further, after forming the conductive film 121 and the conductive film 122 as the first film and the conductive film 142 as the third film, the insulating film 131 as the second film is removed by removing a part of the insulating film. However, the first film to the third film may be formed in any order.

The schematic diagram which shows the condenser microphone by a 1st Example. The top view which shows the condenser microphone by a 1st Example. The schematic diagram for demonstrating the bending part of the diaphragm which concerns on a 1st Example. The schematic diagram which shows the manufacturing method of the capacitor | condenser microphone by a 1st Example. The schematic diagram which shows the manufacturing method of the capacitor | condenser microphone by a 1st Example. The schematic diagram which shows the manufacturing method of the capacitor | condenser microphone by a 1st Example. The schematic diagram which shows the condenser microphone by a 2nd Example. The schematic diagram which shows the manufacturing method of the condenser microphone by a 2nd Example. The schematic diagram which shows the manufacturing method of the condenser microphone by a 2nd Example. The schematic diagram which shows the manufacturing method of the condenser microphone by a 2nd Example.

Explanation of symbols

1, 2: Condenser microphone, 10, 210: Diaphragm, 12, 212: Center part (center part of diaphragm), 14, 214: Bent part (bent part of diaphragm), 30, 230: Back plate (plate), 32 : Through hole, 40: support part, 50: gap, 60: electrode, 121: conductive film (first film), 122: conductive film (first film), 131: insulating film (second film), 132: Insulating film (second film), 142: Conductive film (third film)

Claims (5)

Form the center of the diaphragm by patterning the first film,
Forming a second film on the substrate including the first film by deposition;
Forming a third film on the second film by deposition;
Patterning the third film, removing a portion of the second film and leaving the second film between the first film and the third film, A diaphragm comprising: a multi-layer film including a second film, the second film, and the third film, and extending from the central portion while bending outward from the central portion. Manufacturing method. A plate having fixed electrodes;
A diaphragm having a central portion having a movable electrode and a bent portion extending outward while being bent from the central portion, and vibrating by sound waves;
A method of manufacturing a condenser microphone comprising: a support portion that supports the plate and the outside of the bent portion of the diaphragm while forming a gap between the fixed electrode and the movable electrode,
Forming the central portion of the diaphragm by patterning the first film;
Forming a second film on the substrate including the first film by deposition;
Forming a third film on the second film by deposition;
Patterning the third film, removing a portion of the second film and leaving the second film between the first film and the third film, Forming a bent portion of the diaphragm, comprising a multilayer film including the first film, the second film, and the third film.
Forming the plate with a portion of the third membrane;
The manufacturing method of the capacitor | condenser microphone of Claim 2 including this. In the center,
A first film constituting the central portion; a second film formed on a near end of the first film; and a second film extending from the second film to the outside of the first film. A multi-layered film including three films, and a bent portion extending while bending from the central portion to the outside of the central portion;
A diaphragm comprising A plate having fixed electrodes;
A central portion having a movable electrode; a first film constituting the central portion; a second film formed on a proximal end portion of the first film; and the first film from above the second film. A diaphragm comprising a multilayer film including a third film extending outside the film and having a bent portion extending outward while being bent from the central portion, and a diaphragm vibrating by sound waves;
A support portion that supports the plate and the outside of the bent portion of the diaphragm while forming a gap between the fixed electrode and the movable electrode;
Condenser microphone with

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