KR100643911B1 - Condenser Microphone and Method for manufacturing of the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condenser microphone. In particular, the size of a product can be reduced by reducing the size of the FET and the capacitor by one chip, and the manufacturing process can be simplified. The present invention relates to a condenser microphone and a method of manufacturing the same.

The condenser microphone of the present invention includes a cylindrical case; A diaphragm for detecting vibration of a sound wave signal; A spacer serving as an insulator between the diaphragm and the bipolar plate; A bipolar plate coated with a dielectric material spaced apart from the diaphragm by a predetermined distance from the diaphragm; A base that mechanically supports each component of the case and serves as an insulator for blocking current and charge inside and outside of the case; A connection ring which is an electrical connection means between the bipolar plate and the gate terminal of the FET; In the wafer state, the electrodes of the FET and the capacitor are bumped with gold or lead to protrude, and the bumped wafer is cut with a saw machine and then bonded to the corresponding electrodes on the printed circuit board (PCB). An IC chip and a printed circuit board (PCB) having a pattern for coupling with an electrode bumped in the multi-bare IC chip are formed.

Condenser Microphone, Multi Bear IC Chip, One Chip

Description

Miniature condenser microphone and its manufacturing method {Condenser Microphone and Method for manufacturing of the same}

1 is an assembled perspective view of a conventional condenser microphone

2 is a cross-sectional view of a conventional condenser microphone

3 is a plan view of a multi-bare IC chip in which the FET and capacitor of the condenser microphone of the present invention are one-chip.

4 is a plan view in which a multi-bare IC chip of a condenser microphone of the present invention is flip chip bonded to a printed circuit board.

5 is a manufacturing process diagram of the condenser microphone of the present invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a condenser microphone. More specifically, a condenser microphone is formed by one chip of a FET (a field effect transistor, hereinafter referred to as a "FET") and a capacitor and flip chip bonding the capacitor to a printed circuit board. The present invention relates to a method of manufacturing a condenser microphone suitable for simplifying and miniaturizing a manufacturing method and a process of the same.

In general, a condenser microphone is mainly used as a device for converting voice (sound pressure) into an electrical signal. The type of condenser microphone is dynamic type, condenser type, ribbon type, ceramic type, and the like, and the technology is rapidly developed due to the explosive increase in the demand for information and communication devices and the demand for various functions of users.

In particular, current mobile communication devices have limited product sizes and customer demands require more functions than can be imagined, whereas mobile communication device development and manufacturers are currently in the midst of a trend of wanting even lower prices. The space is very small, but the reality is that we are constantly working on adding more parts and making them cheaper. However, the reality is that the price of the parts does not drop as the size of the mounted parts decreases. The size and price of condenser microphones are no exception.

 The condenser microphone is a microphone using a principle of converting a sound pressure transmitted to a diaphragm into an electrical signal due to a change in electric charge, that is, a change in capacitance, between a diaphragm and a fixed electrode. Hereinafter, a conventional condenser microphone will be described with reference to the accompanying drawings. The explanation is as follows.

1 is an exploded perspective view showing a conventional condenser microphone, and FIG. 2 is a sectional view of a conventional condenser microphone.

As shown in FIG. 1 and FIG. 2, the conventional condenser microphone is provided with a case 120 in which a sound wave inlet 121 is perforated, and is disposed on the case 120, and is provided with dust, moisture, and foreign matter through the sound wave inlet 121. The filter 110 to prevent the case 120 from flowing into the inside, the vibration plate 140 which is located inside the case 120 and detects the vibration of the sound introduced through the sound wave inlet 121, and the diaphragm ( A spacer 150 serving as an insulator between the 140 and the dielectric plate 160 having the dielectric coated thereon, and a base positioned at the bottom of the spacer 150 to prevent and support the flow of each part and to prevent deformation of the overall shape. A gate plate of the bipolar plate 160 coated with a dielectric material spaced apart from the diaphragm by a spacer 150 at a predetermined distance, the base 170, and a lower portion of the bipolar plate 160. A connection ring 180 for contacting the bipolar plate 160 and a conductive material. A printed circuit board 190 having a circuit wired with a material, a FET 200 mounted on the printed circuit board 190 to amplify and convert a potential change according to a change in capacitance, and the FET when switching on the FET. The capacitor 300 includes a capacitor 300 for filtering noise included in an output signal output between the drain terminal and the source terminal, and a printed circuit board 190 on which the FET 200 and the capacitor 300 are mounted.

As shown in FIG. 1, a filter 110, a case 120, a diaphragm 140, a spacer 150, a bipolar plate 160, a base 170, a connection ring 180, and a FET 200 are mounted. The circuit board 300 is sequentially combined to assemble the condenser microphone.

As can be seen in the cross-sectional view of FIG. 2, the size of the condenser microphone depends on the FET 200 and the capacitor 300. Therefore, when mounting the FET 200 and the capacitor 300 separately, there is a problem that the area and volume are limited.

In addition, since the FET 200 and the capacitor 300 are mounted on the printed circuit board, the manufacturing process is complicated.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an ultra-small condenser microphone by converting a FET and a capacitor into one chip.

In addition, an object of the present invention is to provide a condenser microphone that simplifies the manufacturing method and process by making one chip of the FET 200 and the capacitor 300.

The present invention for achieving the above object is a condenser microphone, the cylindrical case 120; A diaphragm 140 installed inside the case to sense vibration of a sound wave signal input through the sound wave inlet 121 from the outside; A spacer 150 provided below the diaphragm to maintain a predetermined distance between the diaphragm and the bipolar plate to serve as an insulator; A bipolar plate 160 coated with a dielectric material spaced apart from the diaphragm at a predetermined distance by the spacer; A base 170 which mechanically supports each part of the case and serves as an insulator for blocking current and charge inside and outside of the case; A connection ring 180 which is an electrical connection means between the bipolar plate 160 and the gate terminal of the FET 200; The FET 410 and the capacitor 420 are configured to include a printed circuit board 500 in which a multi-bare IC chip 400 having one chip is bonded.

In the condenser microphone configured as described above, the case 120, the diaphragm 140, the spacer 150, the bipolar plate 160, the base 170, the connection ring 180, and the printed circuit board 190 have shapes thereof. Since the structure is similar to the conventional one, the detailed description thereof will be omitted.

The multi-bare IC chip is a single chip of the FET and the capacitor. The characteristics, structure, and pattern of the FET are similar to those of the conventional FET, and one side of the FET 410 is in a wafer state. The capacitor 420 is attached to one side of the FET 410 as shown in FIG. 3 in such a manner as to extend to cover the insulating layer and to form the capacitor 420 circuit thereon. As shown in FIG. 3, two capacitors may be inserted and one separately inserted 10,33 pF may be manufactured.

The manufacturing process of the condenser microphone having the above configuration will be described in detail with reference to FIGS. 3, 4, and 5 as follows.

① First, prepare each component. Among the components prepared in this preparation process, components similar to those of the conventional condenser microphone, that is, the case 120, the diaphragm 140, the spacer 150, the bipolar plate 160, the base 170, and the connection ring ( 180), the printed circuit board 500 and the like are similar in size and shape to the conventional ones, so the preparation thereof will be omitted.

② The next step is to form a multi-bare IC chip (400) with one-chip FET and capacitor on the wafer.

One chip of the FET and the capacitor refers to a bare chip structure and pattern in which a capacitor circuit is additionally inserted into the FET 410 as shown in FIG. 3 in the wafer fabrication process of the FET 410. The production process will be described in detail as follows.

First, when making one chip, the characteristics, structure, and pattern of the FET 410 are basically similar to those of the conventional FET 200, and extend to one side of the FET 410 in the wafer state to cover the insulating layer. The capacitor 420 circuit is formed thereon, and the finished product has a shape in which the capacitor 420 is attached to one side of the FET 410 as shown in FIG.

One-chip products can be manufactured by dividing into two capacitors and one 10,33pF.

(3) Next, the multi-bare IC chip (Wafer) in the wafer (wafer) state using a bump bonder of the source 411, drain 412 and gate 413 of the FET 410 electrodes and capacitors An anode (+) 421 and a ground electrode 422 are formed.

(4) Next, the bump-bonded multi-bare IC chip is cut into a dicing saw machine.

⑤ the source 511, drain 512, and gate 513 electrodes of the FET 410, and the capacitor 420 for flip chip bonding a multi-bare IC chip to the printed circuit board 500. The anode 521 and the ground electrode 522 are formed.

⑥ Next, the multi-bare IC chip 400 is installed on the printed circuit board 190 to be electrically connected, but on the multi-bare IC chip 400 Source 411, drain 412, and gate 413 electrodes of FET 410, and anode 421 and ground 422 electrodes of capacitor 420 are formed on a printed circuit board. 511, the drain 512 and the gate 513 electrodes, the anode 521 and the ground 522 electrode patterns of the capacitor 420 abut the direct flip chip bonding.

⑦ Next, epoxy molding is performed to protect the multi-bare IC chip 400 that is flip-chip bonded to the printed circuit board 500.

 The following processes, such as component assembly process, characteristic inspection and packaging, are similar to those of semiconductor COB processes of conventional condenser microphone products.

In the above description, an example of a condenser microphone in which a multi-bare IC chip is bonded to a printed circuit board by a flip-ching bonding method is described and illustrated as an example. However, this is only one embodiment. Applicability of IC chips (Multi-bare IC Chips) to a condenser microphone bonded to a printed circuit board can be easily modified and implemented by those skilled in the art to which the present invention pertains. It is not intended to limit.

By fabricating as described above, the area of the FET and the capacitor can be reduced by bonding the multi-bear IC chip compared to the area of the bonding of the FET and the capacitor, respectively. In addition, the cost of the multi-bearing IC itself is higher, but because the function of the capacitor is included, the material cost is reduced as much as the capacitor purchase cost.

In addition, the FET and capacitor mounting (SMD) work process of the FET and capacitor are eliminated by forming and bonding the FET and the capacitor on one chip, which greatly reduces the investment and labor costs of the production equipment required for the mounting process. It is an advanced invention.

Therefore, according to the method of manufacturing a condenser microphone according to the present invention, a gate, a drain, and a gate of a FET 410 in a wafer state of a multi-bare IC chip in which one chip is formed of a FET and a capacitor. Bump bonding the positive electrode and the ground electrode of the source electrode and the capacitor part, cutting the bump bonded multi-bare IC chip, and flipping the chip on a patterned printed circuit board. Bonding to form the electrical connection between the FET 410 and the capacitor 420 at the same time, thereby dramatically reducing the volume occupied by each of the FET and capacitor components in the conventional manufacturing method, the FET and the capacitor It is effective to achieve miniaturization and ultra-thinning of products by reducing the number of parts by using one chip that is purchased separately. In addition, the characteristics and reliability of the product due to the reduction of the process is improved, material costs are reduced, labor costs and equipment investment costs are reduced.

Although the present invention has been described in detail only with respect to the specific examples described, it will be apparent to those skilled in the art that various changes and modifications can be made within the spirit of the present invention, and such modifications and modifications belong to the appended claims.

Claims (4)

In the condenser microphone A cylindrical case 120; A diaphragm 140 installed inside the case and configured to sense vibration of a sound wave signal input through a sound wave inlet from the outside; A spacer 150 provided below the diaphragm to maintain a predetermined distance between the diaphragm and the bipolar plate to serve as an insulator; A bipolar plate 160 coated with a dielectric material spaced apart from the diaphragm at a predetermined distance by the spacer; A base 170 which mechanically supports each part of the case and serves as an insulator for blocking current and charge inside and outside of the case;  As a bare chip, a wafer formed using a bump bonder in a wafer state, sawing a wafer formed with a source, a drain, a gate electrode, and a cathode (+) and a ground electrode of the capacitor 420 with a dicing saw machine. A multi-bare IC chip 400 having FETs and capacitors in one chip; The pattern is connected to the electrodes of the multi-bearer IC chip 400, respectively, and includes a printed circuit board 500 to which the multi-bare IC chip 400 is bonded. A multi-bare IC chip in which a FET and a capacitor are chipped into a wafer is extended to one side of the FET 410 in a wafer state to cover an insulating layer and form a capacitor 420 thereon. The bonding of the multi-bare IC chip 400 to the printed circuit board 500 allows the surface of each electrode portion of the multi-bare IC chip to directly contact the electrode pattern formed on the printed circuit board. An ultra-small condenser microphone, which uses flip chip bonding technology for bonding. The cylindrical case 120, the diaphragm 140 for detecting the vibration of the input sound wave signal, the spacer 150 to serve as an insulator by maintaining a predetermined distance between the diaphragm and the bipolar plate, and the spacer A dielectric plate coated with a dielectric material spaced apart from the diaphragm by a predetermined distance, and a base that mechanically supports each part of the case and serves as an insulator for blocking current and charge inside and outside of the case ( 170), a printed circuit board 500 to which a multi-bare IC chip 400, in which FETs and capacitors are one-chip, and the multi-bare IC chip 400 are bonded. In the method of manufacturing a condenser microphone consisting of, As a multi-bare IC chip 400 in which the FET 410 and the capacitor are one-chip, the gate 411 and the drain 412 of the FET 410 using a bump bonder in a wafer state. Forming a pattern of the source (413) electrode, the anode (+) 421 and the ground electrode 422 of the capacitor; Cutting the bump bonded multi-bearing IC chip with a dicing saw machine; Flip chip bonding abutting the electrode pattern formed on the printed circuit board and the surface of each electrode of the multi-bearing IC chip; Epoxy molding to protect the chip after connecting the circuit of the FET (410) and the capacitor (420) by the bonding method; In the case, the diaphragm, spacer, bipolar plate, base, the connection ring and the printed circuit board bonded to the multi-bearing ice chip are sequentially made, A multi-bare IC chip in which a FET and a capacitor are integrated into a wafer is formed by extending to one side of the FET 410 in a wafer state, covering an insulating layer, and forming a capacitor 420 thereon. Micro condenser microphone manufacturing method. delete delete

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