JP2961392B2 - Method for manufacturing diaphragm unit in microphone or the like - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condenser microphone, and more particularly to a method for manufacturing a diaphragm unit in a condenser microphone.

[0002]

2. Description of the Related Art As shown in FIG. 4, a method of manufacturing a condenser microphone according to the prior art is usually performed from the opening side of a cup-shaped case 21 usually formed by press working.
Diaphragm tension retaining ring 22, diaphragm 2
3. A spacer ring 24 for securing a gap between the diaphragm and the back electrode, a back electrode 25, and a holder 26 for holding the back electrode are fitted in layers, and the opening peripheral edge 21a is crimped inward to integrate all parts.

[0003]

The method of manufacturing a condenser microphone according to the prior art described above includes a case 21,
The tension retaining ring 22, the diaphragm 23, the spacer ring 24, and the back electrode 25 are stamped parts, and the holder
Since 26 is a synthetic resin molded part, each of them has a dimensional limit in miniaturization, so that it is difficult to miniaturize a condenser microphone as an assembled product of them.

[0004] In addition, the above-mentioned manufacturing method is inferior in mass productivity because individual parts are sequentially assembled and assembled. In addition, the condenser microphone is often required to have a flash surface on the surface of the diaphragm due to its acoustic characteristics. However, in the condenser microphone manufactured by the above-described manufacturing method, a space is formed on the front surface of the diaphragm 23 by the case 21 and the tension retaining ring 22, and the space becomes a resonance tube.

[0005]

SUMMARY OF THE INVENTION A method of manufacturing a condenser microphone of the present invention, particularly a vibrating membrane unit in a condenser microphone, comprises the steps of forming an appropriate number of small holes in an insulator or an insulator-coated substrate; Forming a spacer portion having a predetermined thickness in an area surrounding the hole drilling area and an outer area thereof; coating a metal film on the hole drilling area and the inner peripheral surface of the hole on both surfaces of the substrate to form electrodes and Forming the back electrode, placing the thermocompression bonding material on the substrate outside the inner spacer portion, and further mounting the diaphragm film material on the thermocompression bonding material, from the surface of the diaphragm film material A step of pressing the vibrating film material to the substrate by pressing with a hot press, and fixing the vibrating film material in parallel to the surface of the substrate through an adhesive layer having a thickness of the spacer portion, and an extra area outside the bonding site. Cutting off the diaphragm material , And a step of connecting the signal line to the electrode.

[0006] Also, a step of separately drilling an appropriate number of small holes in an insulator or an insulator-coated substrate, and a spacer portion having a predetermined thickness in an area surrounding the area where the holes are drilled in the substrate and an outer area thereof. The step of forming, the step of forming electrodes and back electrodes by coating a metal film on the inner peripheral surface of the small holes and the inner peripheral surface of the small holes on both surfaces of the substrate, Placing the surrounding spacer piece on the surface of the substrate, placing the thermocompression-bonded sheet on the spacer piece, and further placing the vibrating film material on the thermocompression sheet, the surface of the vibrating film material A process of pressing the vibrating film material together with the spacer pieces together with the substrate by pressing with a hot press from above, and fixing the vibrating film material in parallel to the surface of the substrate through the thickness of the spacer pieces, and an extra vibrating film material outside the bonding site And connecting the signal lines to the electrodes There.

Further, after the above-described steps are simultaneously performed on each grid of a large-sized substrate material having a grid of an appropriate size, the substrate material is divided into the respective grids to simultaneously manufacture a number of diaphragm units. May be. At that time, the vibrating film material and the thermocompression bonding material are placed so as to cover the whole area of the substrate material.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a diaphragm unit M such as a microphone according to an embodiment of the present invention will be described with reference to the drawings.
In the method of manufacturing the vibrating membrane unit M in the first embodiment, the first step is to place a laser on a central region of an appropriate insulator plate, for example, a substrate 1 of alumina or glass, or a substrate 1 in which a metal plate is coated with an insulator. An appropriate number of small holes 2, 2,... Are formed by processing or ultrasonic processing. In the case of an alumina substrate, the small holes 2 can be formed in advance with a mold.
The number of small holes 2 is determined according to the characteristics of the microphone, and is, for example, one to three. (FIG. 1A) The small holes 2 serve both for damping and for forming electrodes.

In the second step, a thick film printing technique is used to form an insulator or a conductor on the central area of the surface of the substrate 1, that is, the area surrounding the perforated area of the small holes 2, 2,. A spacer portion, in the illustrated example, an annular spacer portion 3 and parallel linear spacer portions 4, 4 are formed, and the surfaces of the spacer portions 3, 4, 4 are accurately parallelized by lapping, and the spacer portions 3, 4 are formed. 4 and 4 are finished to predetermined dimensions, for example, 25 μm. (FIG. 1 (b))

In the third step, small holes 2, 2,...
A mask is applied while leaving a perforated area, and vacuum deposition is performed. .. And the inner peripheral surfaces of the small holes 2, 2,... Are coated with a metal coating, for example, a gold coating. And the electrode 6 are integrally formed, and the through hole 10 for damping remains.
(Fig. 1 (c))

In a fourth step, a thermocompression tape 7 having a width between the inner side surfaces of the outer spacer portions 4 and 4 and punching a circular hole into which the inner spacer portion 3 is to be fitted is formed.
Is placed on the substrate 1 so as to be located between the inner spacer section 3 and the outer spacer sections 4 and 4 (FIG. 1 (d)). Further, a resin film, for example, PET (terephthalic acid) having a thickness of 2 μm A vibrating film material 8 obtained by coating a metal (eg, gold or nickel) to a thickness of 400 angstroms on a (polyethylene) film is placed on the thermocompression bonding tape 7. (Fig. 1 (e))

In a fifth step, the vibrating film material 8 is pressed from the surface of the vibrating film material 8 by a hot press so that the vibrating film material 8 is
Crimp to At this time, the spacer portions 3, 4, and 4 prevent the thermocompression bonding tape 7, that is, the adhesive from melting out, and the vibrating film material 8 is interposed through the adhesive layer having the thickness of the spacer portions 3, 4, and 4. And fixed parallel to the surface of the substrate 1. (Figure 1
(F))

In a sixth step, an extra vibrating film material 8 outside the outer spacer portions 4 and 4 is cut off, and a signal line 9 is connected to the electrode 6. (FIG. 1 (f))

In the method of manufacturing the vibrating membrane unit M according to the second embodiment, the first step is to set a suitable insulator plate, for example, a substrate 1 of alumina or glass, or a center of the substrate 1 in which a metal plate is coated with an insulator. An appropriate number of small holes 2, 2,... Are formed in the region as in the first embodiment. (FIG. 2 (a))

In the second step, as in the third step of the first embodiment, a mask is applied while leaving the small holes 2, 2,... .. And the inner peripheral surfaces of the small holes 2, 2,... Are coated with a metal coating, for example, a gold coating. And the electrode 6 are integrally formed, and the through hole 10 for damping remains. (FIG. 2 (b))

In the third step, a spacer piece 3A of an insulator or a conductor, which has been etched and surrounds the central area of the surface of the substrate 1, that is, the area where the small holes 2, 2,. Place on. (FIG. 2 (c))

In the fourth step, a thermocompression bonding tape 7 having substantially the same shape as the spacer piece 3A is placed on the spacer piece 3A, and a vibrating film material 8 obtained by coating a resin film, for example, a PET film with a metal, for example, gold, is used. Is placed on the thermocompression bonding tape 7. (Fig. 2 (d))

In the fifth step, the vibrating film 8 is pressed against the substrate 1 together with the spacer pieces 3A by pressing the surface of the vibrating film 8 with a hot press. At that time, the spacer piece 3
The adhesive of the thermocompression bonding tape 7 flows out to the etched portion A, and the diaphragm film material 8 is fixed in parallel to the surface of the substrate 1 via the spacer pieces 3A. (Fig. 2 (d))

In the sixth step, an extra vibrating film material 8 outside the outer spacer portions 4 and 4 is cut off, and a signal line 9 is connected to the electrode 6. (FIG. 2 (e))

The vibrating membrane unit M in the manufacturing method of the above-described embodiment describes one grid of a large-sized substrate material which is a grid of appropriate dimensions. After the above-described steps are simultaneously performed on each square of a large-sized substrate material having a grid of appropriate dimensions, the substrate material is cut into a large number of substrates 1 of each square, so that a large number of vibrating membranes are formed. The unit M is manufactured. At this time, the vibrating film material 8 is a sheet corresponding to the entire surface of the substrate material. Further, the thermocompression bonding tape 7 is a continuous tape formed with a hole corresponding to the diaphragm unit M,
Or a sheet similar to the substrate material.

Further, it is more convenient if each grid on the back surface of the substrate material is subjected to a known processing in which a processing circuit such as a microphone is provided in advance. In the manufacturing method of the above embodiment, processing can be performed even if one grid has a size of about 3 mm to 1 mm.

As shown in FIG. 1F or FIG. 2E, the diaphragm unit M manufactured by the manufacturing method of the above embodiment has a back electrode 5 on the surface where the through hole 10 for damping is formed. The vibration film 8 is fixed on the front surface of the substrate 1 provided with the electrodes 6 on the back surface thereof at a distance of the thickness of the spacer portions 3 and 4 or the spacer piece 3A so as to face the back electrode 5 via an adhesive layer. A signal line 9 is connected to the electrode 6 integrated with the back electrode 5, and a processing circuit such as a microphone is printed on the back surface of the substrate 1 as necessary. And such a diaphragm unit M is used for a microphone or a differential pressure type pressure sensor.

In the microphone, as shown in FIG. 3A, a substrate 1 is fitted on the inner peripheral surface of a casing A, and a back pressure chamber B is formed on the back surface of the substrate 1. In the differential pressure type pressure sensor, as shown in FIG. 3B, the substrate 1 is fitted to an intermediate portion of the inner peripheral surface of the casing A, and the casing A
Is divided into two chambers C and D by the diaphragm unit M. In the chamber C, an inlet E communicating with the gas part at the pressure P ₁ is provided.
The Branch D, inlet F in communication with the gas portion of the pressure P ₂ is respectively open.

[0024]

According to the method for manufacturing a diaphragm unit in a microphone or the like of the present invention, a diaphragm unit as a component part of a microphone or the like has a high degree of freedom in material selection in a microphone, and has high mass productivity and a small size. Is easily manufactured, and the microphone or the like is manufactured simply by incorporating the vibrating membrane unit. Therefore, the microphone or the like itself has high mass productivity and can be easily manufactured in a small size.

Further, in manufacturing the diaphragm unit,
For example, the use of a vibrating membrane made of a material such as FEP (propylene hexafluoride / tetrafluoroethylene copolymer) makes it easy to make a microphone or the like an electret. Further, in a microphone or the like using the above-mentioned diaphragm unit, since a space in front of a diaphragm serving as a resonance tube is not formed as in a microphone or the like according to a conventional manufacturing method, it is excellent in acoustic characteristics.

[Brief description of the drawings]

FIG. 1 is an explanatory view illustrating steps of a method for manufacturing a diaphragm unit in a microphone or the like according to a first embodiment of the present invention.

FIG. 2 is an explanatory view of a process of a method of manufacturing a diaphragm unit in a microphone or the like according to a second embodiment of the present invention.

FIG. 3 is a schematic sectional view of a microphone using a diaphragm unit in a microphone or the like of the present invention and a differential pressure type pressure sensor.

FIG. 4 is an explanatory diagram of steps of a method for manufacturing a microphone according to a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2 Small hole 3, 4 Spacer part 3A Spacer piece 5 Back electrode 6 Electrode 7 Thermocompression tape 8 Vibration film material 9 Signal line 10 Through hole

Claims (4)

(57) [Claims] 1. A process of forming an appropriate number of small holes in an insulator or an insulator-coated substrate, and forming a spacer portion having a predetermined thickness in a region surrounding a region where the small holes are formed in the substrate and an outer region thereof. A step of forming electrodes and back electrodes by coating a metal film on the perforated area of the small holes on both sides of the substrate and the inner peripheral surface of the small holes, and applying a thermocompression bonding material on the substrate outside the inner spacer portion. Placing the diaphragm film material on the thermocompression bonding material, pressing the surface of the diaphragm film material by a hot press to crimp the diaphragm film material to the substrate, and then placing the diaphragm film material in the spacer. Vibrating membrane, comprising: a step of fixing in parallel to the surface of the substrate via an adhesive layer having a thickness of a portion, and a step of cutting off excess vibrating film material outside the bonding area and connecting a signal line to an electrode. Unit manufacturing method. 2. A process of forming an appropriate number of small holes in an insulator or an insulator-coated substrate, and forming a spacer portion having a predetermined thickness in an area surrounding the area where the small holes are formed in the substrate and an outer area thereof. A step of forming an electrode and a back electrode by coating a metal film on the inner peripheral surface of the small hole and the inner peripheral surface of the small hole on both surfaces of the substrate, and performing etching to surround the small hole drilling region of the substrate. Placing a spacer piece on the surface of the substrate, placing a thermocompression tape on the spacer piece, and further placing a diaphragm film material on the thermocompression tape, from the surface of the diaphragm film material A step of pressing the vibrating film material together with the spacer pieces together with the substrate by pressing with a hot press, and fixing the vibrating film film material in parallel with the surface of the substrate through the thickness of the spacer pieces, and an extra vibrating film material in a region outside the bonding site. Cutting and connecting the signal line to the electrode Knit manufacturing method. 3. A process of perforating an appropriate number of small holes in each grid of a large-sized substrate material having a grid of an appropriate size, an area surrounding a perforated area of a small hole in each grid, and an outside thereof. Process of forming a spacer part of a predetermined thickness in the entire area of the substrate material, forming a hole in the small hole on both sides of the substrate and covering the inner peripheral surface of the small hole with a metal film to form electrodes and back electrodes in the whole material of the substrate Placing the thermocompression bonding material over the entire area of the substrate material on the substrate outside the inner spacer portion, and further placing the vibrating film material on the thermocompression bonding material over the entire substrate material area, A step of pressing the vibrating film material to the substrate by pressing the film film material from the surface with a hot press, and fixing the vibrating film material in parallel with the surface of the substrate via an adhesive layer having a thickness of a spacer portion, Step of cutting off extra vibrating film material in the outer region and connecting signal lines to electrodes And a step of dividing the substrate material into grids. 4. A process of perforating an appropriate number of small holes in each grid of a large-sized substrate material having a grid of an appropriate size, a step of forming small holes on both sides of the substrate and an inner peripheral surface of the small holes. Cover the metal film with electrodes
A process of forming a back electrode over the entire substrate material, a process of placing a spacer piece that is etched and surrounding a perforated area of a small hole on the substrate over the entire surface of the substrate material, A step of placing the thermocompression bonding material over the entire area of the substrate material and further placing the vibrating film material on the thermocompression bonding material. A step of crimping both pieces to the substrate and fixing them in parallel to the surface of the substrate via the thickness of the spacer pieces, cutting off excess vibrating film material outside the bonding area, and connecting signal lines to the electrodes; and A method for manufacturing a vibration membrane unit, comprising a step of dividing a substrate material into each grid.