JP2008294733A - Microphone element mounting board and microphone device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microphone element mounting board which can assure the flatness of a mounting area, can improve a cleaning property by discharging a plating solution invading into a hollow part satisfactorily when the board is immersed into the plating solution and is excellent in the mountability of a microphone element and electric connectivity between wiring conductors. <P>SOLUTION: The board 101 has a recessed part 104 in the mounting area 102, a plate member 112 is connected so as to close the recessed part 104 and form the hollow part 115 between with the board 101, and an opening part 109 connecting to the hollow part 115 is formed in the plate member 112. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a microphone element mounting substrate for mounting a microphone element, and a microphone device using the same.

  2. Description of the Related Art In recent years, microphone devices that can output input sound as an electrical signal have been widely used in communication devices such as mobile phones and automobile phones, or electronic devices such as information devices such as small IC recorders using semiconductor memories. Has been.

  As shown in FIG. 3, such a microphone device includes a microphone element 303 that mainly outputs input sound as an electrical signal, and a base 305 having a mounting area 302 for housing the microphone element 303 and a base 305. The substrate 301 includes a frame portion 304 formed on the upper portion, and a cap 306 that closes the mounting region 302.

In order to improve the sensitivity of the microphone device, a cavity (not shown) is provided in the mounting region 302 of the microphone element 303, and the cavity is connected to the sound hole formed in the microphone element 303. There has been proposed an efficient microphone device in which the conversion efficiency of the sound 307 is increased by obtaining an acoustic effect due to resonance in the sound. The cavity can be formed, for example, by stacking three insulating layers in the base 305 below the mounting region 302. In this case, an intermediate insulating layer having a large opening serving as a cavity is stacked on the upper side of the lower insulating layer serving as the bottom surface of the base 305, and further an upper layer having a small opening so as to communicate with the sound hole. By stacking the insulating layers, the substrate 301 in which the cavity and the opening communicate with each other is formed. The opening is formed in a plan view so as to communicate with the cavity at a location where the microphone element 303 is not mounted. The sound 307 entering from the outside passes through the sound hole formed in the microphone element 303, obtains an acoustic effect due to resonance in the cavity, and spreads in the upper space of the mounting area 302, and as a result, the detection part of the microphone element 303 is good Sound can be detected.
JP 2003-153392 A

  However, in the conventional microphone device, an insulating layer of an intermediate layer having a large opening serving as a cavity is laminated on the lower insulating layer serving as a bottom surface of the base, and a small opening so as to communicate with the sound hole. Due to the structure in which the upper insulating layer having the upper layer is laminated, the strength around the opening of the upper insulating layer is insufficient, so that the mounting region may be deformed by lamination, pressurization, or the like. As a result, when the microphone element is mounted, there is a problem that the distance between the opening of the cavity and the sound hole of the microphone element tends to vary, and sound cannot be detected satisfactorily.

  In addition, in order to deposit a nickel plating layer or a gold plating layer on the wiring conductor formed on the exposed surface of the substrate, when the microphone element mounting substrate is immersed in a plating solution, the plating solution that has penetrated into the cavity is removed. There was a problem that it was difficult to discharge and clean. The plating solution is a solution of nickel or other metal compound. If this plating solution remains in the recess of the microphone element mounting substrate, the wiring conductor may be corroded, and connection failure occurs when the microphone element is mounted. May occur or the microphone device may malfunction.

  The present invention was devised in view of the above circumstances, and its purpose is to improve the flatness of the mounting region in the microphone element mounting substrate in which the cavity is formed, and immerse the substrate in the plating solution. In this case, it is possible to improve the washability by improving the drainage of the plating solution that has entered the cavity, and the microphone element mounting substrate having excellent microphone element mounting properties and electrical connection between wiring conductors. Is to provide.

  The microphone element mounting substrate of the present invention has a recess in the mounting region, and a plate member is bonded so as to close the recess and form a cavity between the substrate and the substrate. An opening connected to the portion is formed.

  In the microphone element mounting substrate of the present invention, it is preferable that the main surface of the plate member on the cavity portion side is located on the cavity portion side of the main surface of the substrate around the plate member. Features.

  In the microphone element mounting substrate of the present invention, preferably, the height position of the main surface around the plate member of the substrate is located between both main surfaces in the thickness direction of the plate member. .

  The microphone element mounting substrate of the present invention is preferably characterized in that the substrate has a protruding portion in which an opening peripheral edge of the recess protrudes inward.

  In the microphone element mounting substrate of the present invention, preferably, the arithmetic average roughness of the upper surface of the plate member is larger than the arithmetic average roughness of the lower surface.

  In the microphone device of the present invention, a microphone element having a sound hole is mounted on the main surface of the plate member of the microphone element mounting substrate according to any one of the above so that the opening and the sound hole communicate with each other. It is characterized by.

  In the microphone device of the present invention, preferably, a microphone element having a sound hole is formed on the main surface around the plate member of the substrate of the microphone element mounting substrate described in any of the above, and the opening and the sound hole. It is mounted so as to communicate with each other.

  In addition, the microphone device of the present invention is preferably characterized in that the external shape of the opening is different from the external shape of the sound hole in a plan view.

  The microphone element mounting substrate of the present invention has a recess in the mounting region, and a plate member is joined so as to close the recess and form a cavity with the substrate. The plate member has an opening connected to the cavity. Since the portion is formed, the flatness of the mounting region can be improved by forming the mounting region on which the microphone element is mounted with a plate member. As a result, when the microphone element is mounted, variation in the distance between the opening of the cavity and the sound hole of the microphone element can be reduced, and sound can be detected satisfactorily.

  In addition, when the plating layer is deposited on the wiring conductor formed on the exposed surface of the substrate, the opening of the cavity before the plate member is joined can be widened, so that the plating solution that has entered the cavity can be discharged. Can be improved.

  In the microphone element mounting substrate of the present invention, preferably, the main surface of the plate member on the cavity portion side is located on the cavity portion side with respect to the main surface of the substrate around the plate member. Even if the plate member is bonded onto the cavity, the plate member is bonded so that a part of the thickness of the plate member overlaps with a part of the thickness of the substrate.

  In the microphone element mounting substrate of the present invention, preferably, the height position of the main surface around the plate member of the substrate is located between both main surfaces in the thickness direction of the plate member. By mounting the board member on the main surface around the board member so as to cover the board member, the distance between the lower surface of the microphone element and the upper surface of the plate member can be reduced, and the gap between the microphone element and the plate member is reduced. It is possible to minimize the sound leakage from the communicating sound hole.

  In the microphone element mounting substrate of the present invention, it is preferable that the substrate has a protruding portion in which the opening peripheral edge portion of the concave portion protrudes inward, so that the plate member can be favorably held by the protruding portion. Further, since the bonding area around the lower surface of the plate member and the opening is increased, the plate member can be firmly bonded to the substrate.

  Further, the microphone element mounting substrate of the present invention preferably has an arithmetic average roughness of the upper surface of the plate member larger than that of the lower surface, so that when the microphone element is directly mounted on the main surface of the plate member, When the microphone element is bonded to the plate member serving as the mounting region with the bonding material, the bonding between the plate member and the microphone element can be improved, and the bonding strength can be increased.

  In the microphone device of the present invention, a microphone element having a sound hole is mounted on the main surface of the plate member of the microphone element mounting substrate described above so that the opening and the sound hole communicate with each other. When manufacturing the element mounting substrate, even if the flatness around the mounting area deteriorates due to lamination, pressurization, etc., the flatness of the plate member is ensured. When the microphone element is mounted, the variation in the distance between the cavity opening and the sound hole of the microphone element can be reduced, and sound can be detected well.

  In the microphone device of the present invention, preferably, a microphone element having a sound hole is provided on a principal surface around the plate member of the substrate of the microphone element mounting substrate according to any one of the above, and an opening and a sound hole are provided. Since it is mounted so as to communicate with each other, the opening of the plate member and the sound hole of the microphone element can be communicated with each other at intervals with little variation, and the sound resonated in the cavity can be efficiently and It can be detected stably.

  Further, the microphone device of the present invention is preferably configured so that a positional deviation occurs when the microphone element is mounted on the mounting region because the outer shape of the opening portion is different from the outer shape of the sound hole in a plan view. In addition, it is possible to suppress the opening of the hole communicating with a part of the sound hole of the microphone element overlapping with a part of the opening in a plan view.

  Hereinafter, embodiments of a microphone mounting substrate and a microphone device according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1A is a plan view showing an example of an embodiment of a microphone device using a microphone element mounting substrate of the present invention, and FIG. 1B is a cross-sectional view taken along line XX ′ in FIG. It is sectional drawing. FIG. 1 shows a structure seen through the cap in order to make it easy to understand the state in which the cap is joined, and the position of the cap is indicated by a broken line. Further, FIG. 2 shows an example of an embodiment of a microphone device using another microphone element mounting substrate of the present invention in the same manner. The symbols shown in FIG. 1 and FIG. 2 are the same symbols for easy understanding.

  1A and 1B, 101 is a substrate, 102 is a mounting area, 103 is a microphone element, 104 is a recess, 105 is a cap, 107 is a sound hole formed in the cap 105, and 108 is a microphone element. 103 is a sound hole formed. A cavity 115 is formed below the microphone element 103, and the plate member 112 is fixed by a bonding material 111 or the like so as to close the cavity 115. The plate member 112 has an opening 109 connected to the cavity 115. Furthermore, the sound hole 108 and the opening 109 are arranged vertically so as to communicate in the vertical direction.

  In this embodiment, the substrate 101 includes a base portion 116 on which the microphone element 103 is mounted and a frame portion 117 on which the cap 105 is covered, and a mounting region 102 for storing the microphone element 103 is formed. The shape is, for example, a rectangular parallelepiped shape and has a concave mounting region 102 on the upper surface.

  In addition, a wiring conductor (not shown) is led out from the periphery of the mounting area 102 of the substrate 101 to the lower surface, and the electrode of the microphone element 103 is soldered to a portion of the wiring conductor exposed at the periphery of the mounting area 102. The bumps 122 and the bonding wires 123 are connected.

  The wiring conductor is made of a metal material such as tungsten, molybdenum, copper, or silver, and is formed in the form of a metallized layer, a plating layer, or the like. For example, if the wiring conductor is made of a metallized layer of tungsten, a metal paste produced by adding an organic solvent and a binder to tungsten powder is printed in a predetermined pattern on the insulating layer to be the substrate 101. It is formed.

  The cavity 115 includes a first insulating layer 118 in which the cavity 115 is not formed, and a second insulating layer in which a hole to be the cavity 115 is formed, for example, by forming a laminated structure forming the base 116 in a four-layer structure. 119, a third insulating layer 120 in which a hole serving as a cavity 115 is formed and joined to the lower surface of the plate member 112, and a hole in which the plate member 112 is inserted is formed and joined to the side surface of the plate member 112. The four insulating layers 121 are sequentially stacked. Further, by laminating a frame-shaped insulating layer to be the frame portion 117 on the laminated body to be the base portion 116, a microphone element mounting substrate having a concave mounting region 102 on the upper surface is formed.

  A plating layer is attached to a wiring conductor (not shown) formed on the exposed surface of the substrate 101. For example, a nickel plating layer having a thickness of about 1 to 10 μm and a gold plating layer having a thickness of about 0.1 to 3 μm are preferably sequentially deposited on the exposed surfaces of the wiring conductor and the external terminal electrode 114. As a result, oxidation of the wiring conductor, the external terminal electrode 114, and the like can be effectively prevented, and the bonding wire connectivity and solder wettability to the wiring conductor can be improved. Can be improved.

  In this embodiment, the microphone element mounting substrate of the present invention has a plate member 112 such that the substrate 101 has a recess 104 in the mounting region 102 and closes the recess 104 to form a cavity 115 between itself and the substrate 101. The plate member 112 has an opening 109 connected to the cavity 115. With such a structure, the flatness of the mounting region 102 can be improved. As a result, when the microphone element 103 is mounted, variation in the distance between the opening of the cavity 115 and the sound hole of the microphone element 103 can be reduced, and sound can be detected satisfactorily. That is, when the cavity 115 is formed so as to cover the concave portion 104 with the fourth insulating layer 121 having an opening as in the prior art, the strength is insufficient around the opening and the fourth insulating layer 121 is formed by lamination, processing, or the like. Although it was easy to deform | transform, flatness is securable by setting it as the structure of this invention. Therefore, the mountability of the microphone element 103 can be improved, and the distance between the lower surface of the microphone element 103 and the upper surface of the mounting region 102 (the upper surface of the plate member 112 in FIG. 1) is set to a desired one. Can do.

  The substrate 101 is formed by laminating a plurality of insulating layers made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass ceramic sintered body. The substrate 101 is formed by laminating and firing a plurality of flat or frame ceramic green sheets having a thickness of about 0.1 to 0.5 mm. The cavity 115 is for amplifying the sound 106 by entering the sound 106 by resonance. Such a cavity 115 has a larger outer shape than the plate member 112 in a plan view.

  Further, when the plating layer is applied to the wiring conductor formed on the exposed surface of the substrate 101, the opening of the cavity 115 before the plate member 112 is joined can be widened, so that the plating that has entered the cavity 115 can be obtained. The liquid discharge performance can be improved. Such a plating layer, for example, produces a mother substrate (not shown) in which wiring board regions to be the substrate 101 are arranged in rows and columns and forms a frame-like plating conduction pattern on the outer periphery of the mother substrate. Then, hold the plating conduction pattern with the plating jig and immerse it in the plating solution. Further, in the plating solution, a current is passed from the terminal of the jig to the wiring conductor and the external terminal electrode 114 via the plating conduction pattern. It is formed by the panel plating method to supply. At this time, the plating solution also enters the cavity 115 formed in the base 116 by immersing the mother substrate in the plating solution. However, the plate member 112 is bonded to the substrate 101 before the plating is applied. In addition, since the opening of the cavity 115 can be widened, it is possible to improve the discharge performance of the plating solution that has entered the cavity 115 after the plating process is completed. The final plating process includes a cleaning process and a drying process. Due to the good drainage of the plating solution that has entered the cavity 115, contamination of the cleaning solution with the plating solution and stains due to insufficient cleaning (plating solution residue) There is also an effect of suppressing the occurrence of. By such an effect, it is possible to suppress the corrosion of the wiring conductor, and to reduce the possibility that a connection failure will occur when the microphone element 103 or the like is mounted, or that the microphone device will malfunction.

  In the microphone element mounting substrate of the present invention, preferably, the main surface of the plate member 112 on the cavity 115 side is the main surface of the substrate 101 around the plate member 112 (that is, the plate member 112 of the main surface of the substrate 101). It is characterized in that it is located closer to the cavity 115 than the portion along the outer periphery. Because of such a structure, even if the plate member 112 is bonded onto the cavity 115, the plate member 112 is bonded so that a part of the thickness of the plate member 112 overlaps a part of the thickness of the substrate 101. Can be bonded to the substrate 101 accurately and firmly.

  Further, since the volume of the cavity 115 can be easily adjusted by adjusting the height position of the main surface of the plate member 112 located on the cavity 115 side, the cavity 115 capable of obtaining an optimal acoustic effect is obtained. Can be formed. For example, the lower side of the plate member 112 joined to the mounting region 102 is protruded so as to be inserted into the cavity portion 115 to reduce the volume of the cavity portion 115, or a hollow portion is further formed below the plate member 112. Thus, the volume of the cavity 115 can be increased.

  The microphone element mounting substrate of the present invention is preferably characterized in that the height position of the main surface of the substrate 101 around the plate member 112 is located between both main surfaces in the thickness direction of the plate member 112. To do. Because of such a structure, the microphone element 103 is mounted on the main surface around the plate member 112 of the substrate 101 so as to cover the plate member 112 as shown in FIGS. The distance between the lower surface and the upper surface of the plate member 112 can be close. As a result, the gap between the microphone element 103 and the plate member 112 can be minimized, and sound leakage from the gap between the communicating sound holes 107 and 108 can be suppressed. When the microphone element 103 is mounted on the mounting area 102, a plurality of wiring conductors having solder bumps 122 bonded to a surface of the mounting area 102 facing the lower surface of the microphone element 103 are formed. The terminal electrode formed on the wiring conductor can be electrically and mechanically joined to the wiring conductor by the bump 122.

  At this time, for example, when the height of the bump 122 after bonding is 50 μm, the height position of the upper surface of the plate member 112 is made higher by about 30 μm than the height position of the main surface of the substrate 101 around the plate member 112. Thereby, the space | interval of the lower surface of the microphone element 103 and the upper surface of the board member 112 can be made smaller, and the sound leakage from the clearance gap between the sound holes 107 and 108 which communicates can be suppressed.

  The microphone element mounting substrate of the present invention is preferably characterized in that the substrate 101 has a protruding portion 113 in which an opening peripheral edge portion of the recessed portion 104 protrudes inward. Since it was set as such a structure, the board member 112 can be favorably hold | maintained by the protrusion part 113. FIG. Further, since the bonding area between the lower surface of the plate member 112 and the periphery of the opening 109 is increased, the plate member 112 can be firmly bonded to the substrate 101.

  Here, as the bonding material 111 for fixing the plate member 112 so as to close the concave portion 104 of the mounting region 102, a hard resin, for example, an epoxy resin, is used so as to hardly absorb the vibration of the sound 106 entering from the sound hole 108. It is desirable to join by such as. Further, in the case where the plate member 112 is made of an inorganic material such as ceramic, the plate member 112 can be bonded by a harder bonding material such as low melting point glass. In this case, the vibration of the sound 106 entering from the sound hole 108 is preferable because the glass of the bonding material 111 is more difficult to absorb.

  The microphone element mounting substrate of the present invention is preferably characterized in that the arithmetic average roughness of the upper surface of the plate member 112 is larger than the arithmetic average roughness of the lower surface. Because of this structure, when the microphone element 103 is directly mounted on the main surface of the plate member 112, when the microphone element 103 is bonded to the plate member 112 serving as the mounting region 102 by the bump 122 such as resin, The bonding between the plate member 112 and the microphone element 103 can be made favorable, and the bonding strength can be made strong. The lower surface of the plate member 112 has a lower arithmetic average roughness from the viewpoint of suppressing the absorption of sound in the cavity 115, and therefore the arithmetic average roughness of the upper surface of the plate member 112 is preferable. Is preferably larger than the arithmetic average roughness of the lower surface.

  For example, the arithmetic average roughness of the upper surface of the plate member 112 is obtained by performing a blasting process or applying a resin paste containing coarse particles so that a fine uneven shape is formed on the upper surface of the plate member 112. Can be formed to be larger than the arithmetic average roughness of the lower surface. By forming a fine uneven shape on the upper surface of the plate member 112, when the microphone element 103 is directly mounted on the main surface of the plate member 112, a resin as a bonding material enters between the fine uneven shapes. The mechanical strength between the microphone element 103 and the plate member 112 is improved. As another method, in the course of manufacturing the plate member 112, the manufacturing process can be simplified if it is integrally formed so that the arithmetic average roughness of the upper surface of the plate member 112 is larger than the arithmetic average roughness of the lower surface from the beginning. Can be

  In the microphone device of the present invention, the microphone element 103 having the sound hole 108 is mounted on the main surface of the plate member 112 of the microphone element mounting substrate described above so that the opening 109 and the sound hole 108 communicate with each other. It is characterized by that. That is, the microphone element 103 is bonded to the main surface of the plate member 112, and the electrode of the microphone element 103 and the wiring conductor formed on the substrate 101 are electrically connected by a bonding wire, or the wiring conductor is also connected to the plate member 112. Then, the microphone element 103 may be electrically connected to the wiring conductor with solder or the like. With this structure, even when the microphone element mounting substrate is manufactured, the flatness of the plate member 112 is ensured even if the flatness around the mounting region 102 deteriorates due to lamination and pressure. As a result, the mountability of the microphone element 103 in the mounting region 102 can be improved, and when the microphone element 103 is mounted, the variation in the distance between the opening of the cavity 115 and the sound hole of the microphone element 103 is reduced. It can be made small and sound can be detected well.

  For example, if the microphone element 103 is a silicon type made of MEMS (Micro-electromechanical System), a vibration film made of very thin silicon is manufactured by photoetching or vapor deposition, and the vibration film is detected by a sound pressure sensor (detection). This is a structure that captures the movement of the diaphragm as a change in capacitance. Since the microphone element 103 having the sound hole 108 is mounted in the mounting region 102 of the microphone element mounting substrate as in this structure so that the opening 109 and the sound hole 108 communicate with each other, the sound 108 is transmitted through the cavity 115. Then, the sound pressure acts on the vibration film of the microphone element 103 almost evenly around the sound hole 108, and the vibration of the sound 106 is transmitted to the vibration film to efficiently move the vibration film. It can be understood as a change in capacitance.

  Further, according to the configuration of the microphone device of the present invention, the cavity 115 can be satisfactorily formed below the microphone element 103 even when the microphone device is downsized and the area of the mounting region 102 of the substrate 101 is reduced. An efficient and small microphone device that can obtain the acoustic effect by the cavity 115 can be realized.

In addition, it is desirable that the outer peripheral shape of the cavity 115 is processed into a curved shape in consideration of the processability of each insulating layer that becomes the cavity 115. Further, the volume of the cavity 115 is formed to be about 2 to 4 times the volume of the sound hole 108 formed in the microphone element 103 in order to effectively obtain the acoustic effect by the sound 106 from the outside. Is preferred.
In addition, as shown in FIGS. 1 and 2, the microphone device of the present invention preferably has a sound hole 108 on the main surface of the substrate 101 around the plate member 112 of the microphone element mounting substrate described above. The microphone element 103 having the above is mounted so that the opening 109 and the sound hole 108 communicate with each other. That is, the microphone element 103 is located above the plate member 112, and the microphone element 103 and the substrate 101 are connected to the outside of the plate member 112. Because of such a structure, the opening of the plate member 112 and the sound hole 108 of the microphone element 103 can be communicated with each other at an interval with little variation, and the sound resonated in the cavity 115 can be transmitted. It can be detected efficiently and stably.

  As an electrical connection means between the microphone element 103 and the substrate 101, for example, a bump 122 made of solder or conductive resin or a bonding wire 123 is used. When the microphone element 103 is fixed to the substrate 101, the outer periphery of the microphone element and the periphery of the recess 104 formed in the mounting portion 102 of the substrate 101 are fixed with bumps 112 made of solder, thermosetting resin, or the like. Thus, a microphone device in which the lower surface of the microphone element 103 and the upper surface of the plate member 112 are adjacent to each other is obtained.

  In addition, the microphone device of the present invention is preferably characterized in that the external shape of the opening 109 is different from the external shape of the sound hole 108 in a plan view. Due to such a structure, even if a displacement occurs when the microphone element 103 is mounted on the mounting region 102, a part of the sound hole 108 of the microphone element 103 is part of the opening 109 in a plan view. It can suppress that the opening of the hole which overlaps and communicates becomes narrow.

  For example, if the opening diameter of the sound hole 108 of the microphone element 103 mounted on the microphone device is 1.0 mm and the opening diameter of the opening 109 formed in the base 116 is 1.2 mm, the microphone element 103 is mounted. If the positional deviation when mounted on the region 102 is theoretically within 0.1 mm, a part of the sound hole 108 of the microphone element 103 does not overlap with a part of the opening 109, and the opening of the communicating hole is constant. Will be kept.

  In the microphone device in which the microphone element 103 is mounted, in order to prevent foreign matter and dust from entering through the sound hole 107 formed in the cap 105, for example, a dustproof plate 110 made of a cloth made of nonwoven fabric, a fine metal mesh, or the like. Etc. are preferably provided above or below the sound hole 107.

  Further, a plurality of external terminal electrodes 114 are formed on the outer peripheral portion of the lower surface of the substrate 101. The external terminal electrode 114 is electrically connected to a wiring conductor (not shown) derived from the mounting region 102. By connecting the external terminal electrode 114 to a mounting pad of an external circuit board (not shown) via a conductive bonding material such as solder or conductive adhesive, the microphone device and the external circuit board are electrically and mechanically connected. Connected to. Further, the microphone element 103 is electrically connected to the electric circuit of the external circuit board via the wiring conductor, the external terminal electrode 114, and the mounting pad.

  In addition, this invention is not limited to the example of above-mentioned embodiment, In the range which does not deviate from the summary of this invention, it can deform | transform into various forms. For example, in the above example, the shape of the substrate 101 is a rectangular parallelepiped shape, but may be a cylindrical shape, an elliptical shape, or the like. Further, although the base 116 where the cavity 115 is formed has a four-layer structure, it may be formed of five or more insulating layers.

  Furthermore, although only the microphone element 103 is shown in the mounting area 102, a driving semiconductor element, a chip capacitor, etc. are similarly mounted in addition to the microphone element 103 in order to optimize the characteristics of the microphone device. May be.

  Further, in FIG. 1 and FIG. 2, the mounting position of the microphone element 103 is on the substrate in the periphery of the plate member. However, when the plate member 103 having a large area is used, the microphone element 103 is placed on the plate member 103 on which the wiring conductor is formed. 103 may be mounted, and the recess 104 may be closed and bonded to the substrate 101 so that the plate member acts as a relay connection substrate.

(A) is a top view which shows an example of embodiment of the microphone element mounting substrate of this invention, and a microphone apparatus, (b) is sectional drawing in XX '. (A) is a top view which shows an example of embodiment of the other microphone element mounting substrate of this invention, and a microphone apparatus, (b) is sectional drawing in YY '. (A) is a top view which shows an example of embodiment of the conventional microphone element mounting substrate and microphone apparatus, (b) is sectional drawing in ZZ '.

Explanation of symbols

101... Substrate 102... Mounting area 103... Microphone element 104... Recess 107.
108 ... Sound hole (microphone element)
109 ... opening 112 ... plate member 113 ... projection 115 ... hollow part

Claims (8)

A microphone element mounting substrate comprising a substrate having a microphone element mounting region, wherein the substrate has a recess in the mounting region, and closes the recess to form a cavity between the substrate and the substrate. A microphone element mounting substrate, wherein a plate member is joined, and the plate member has an opening connected to the cavity. 2. The microphone element mounting substrate according to claim 1, wherein a main surface of the plate member on the cavity portion side is located on the cavity portion side of a main surface of the substrate around the plate member. The microphone element mounting substrate according to claim 2, wherein a height position of a main surface around the plate member of the substrate is located between both main surfaces in a thickness direction of the plate member. The microphone element mounting substrate according to any one of claims 1 to 3, wherein the substrate has a protruding portion in which an opening peripheral edge portion of the concave portion protrudes inward. 5. The microphone element mounting substrate according to claim 1, wherein an arithmetic average roughness of the upper surface of the plate member is larger than an arithmetic average roughness of the lower surface. A microphone element having a sound hole is mounted on the main surface of the plate member of the microphone element mounting substrate according to any one of claims 1 to 5 so that the opening and the sound hole communicate with each other. A featured microphone device. 6. A microphone element having a sound hole on a main surface around the plate member of the substrate of the microphone element mounting substrate according to claim 1 so that the opening and the sound hole communicate with each other. A microphone device characterized by being mounted. The microphone device according to claim 5 or 6, wherein an outer shape of the opening is different from an outer shape of the sound hole in a plan view.

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