KR102208147B1 - Printed circuit board with doom switch and method for fabricating the same - Google Patents

Abstract

In a method for manufacturing a printed circuit board provided with a plurality of dome switches as the printed circuit board used in a portable device, a stepped part formed with a thin inner thickness of a dome guide hole and a thick outer side of the dome guide hole is formed in at least a part of the periphery of the dome guide hole, the outer edge of the metal dome is closely adhered to the stepped part of a dome guide sheet, and the dome guide sheet into which the metal dome is inserted is formed in a thickness range of 0.120 mm to 0.250 mm. By bonding a cover sheet covering the metal dome or knob, which is repeated up and down, with an adhesive layer in the range of 0.010 mm to 0.050 mm thickness, and when mass-manufacturing the dome switch or manufacturing the printed circuit board provided with a plurality of dome switches, it is possible to improve reliability and durability by solving a problem in which a specific layer of a product is peeled off.

Description

Main printed circuit board with dome switch and its manufacturing method {PRINTED CIRCUIT BOARD WITH DOOM SWITCH AND METHOD FOR FABRICATING THE SAME}

The present invention relates to a printed circuit board equipped with a dome switch and a method of manufacturing the same, and more particularly, to a main printed circuit board equipped with a dome switch having a structure capable of improving durability and reliability of a product, and a method of manufacturing the same.

Recently, the need for a printed circuit board (PCB) that is easy to embed in a narrower space is increasing according to the trend of integration, miniaturization, thin film, high density and high bending of electronic products. Accordingly, a printed circuit board capable of miniaturization and high density and having repetitive flexibility has been developed.

As the usage of such printed circuit boards (PCBs) increases rapidly due to technological developments such as mobile phones, DVDs, digital cameras or PDPs, the targets and ranges of which are used are further expanding.

In this way, among printed circuit boards (PCBs), a dome switch is mounted as a miniaturized input device in accordance with the trend of slimming electronic devices, and when pressed by a user's operation, a dome switch is mounted on a printed circuit board used in portable devices such as mobile phones. It is contacted and performs the function of inputting input information. Such a dome switch is provided in a simple and reliable structure, and is widely used because it has an advantage that a user can feel a click.

The general structure of such a dome switch is as follows with reference to FIGS. 1 and 2.

Here, FIG. 1 is an exploded perspective view showing the configuration of a general dome switch according to the prior art, FIG. 2 is an exploded perspective view showing a configuration in which the dome switch is mounted on a PCB, and FIG. 3 is a detailed structure of a dome switch according to the prior art And an operation process.

Referring to FIG. 1, a conventional dome switch 10 is an electrode including a first electrode 13a and a second electrode 13b electrically connected to a circuit pattern 12 designed on a PCB 11. The plate 13 and the reinforcing plate 18 supporting the lower portion of the electrode plate 13 so that the electrode plate 13 separated by two electrodes is mounted on the PCB 11, and the electrode plate 13 A metal dome 15 that is seated on the top and selectively connects the first electrode 13a and the second electrode 13b while being pressed by external pressure, and disposed between the metal dome 15 and the electrode plate 13 And an insulating sheet 14 that electrically separates the two members, and the metal dome 15 is disposed on the upper part of the insulating sheet 14, and the metal dome 15 is inserted in the center, and a through hole for supporting the side thereof is formed. The dome guide sheet 16 fixing the position of 15, and the upper surface of the metal dome 15 disposed on the dome guide sheet 16 and exposed through the dome guide sheet 16 and the through hole It is provided including a cover sheet 17 covering from the outside.

As shown in FIG. 2, the dome switch 10 includes a first port 12a and a second port 12b included in the circuit pattern 12 of the PCB 11 in a state in which each component is mutually fastened. The first electrode 13a and the second electrode 13b of the electrode plate 13 are soldered so that they are respectively connected to each other, and thus can be fastened on the PCB 11.

Accordingly, a company that manufactures electronic devices purchases a dome switch 10 that can be mounted on the PCB 11 while the PCB 11 on which the circuit pattern 12 is formed is provided, and the dome switch 10 is installed on the PCB 11. ), soldering was required.

In addition, when manufacturing a plurality of PCBs 11, each circuit pattern 12 is formed on a single PCB base plate to fit the areas of the plurality of PCBs 11, and then the circuit pattern 12 is cut by cutting each area. A plurality of individually formed PCBs 11 could be simultaneously manufactured.

On the other hand, since the dome switch 11 must be individually soldered for each of the cut PCBs 11, the manufacturing time is increased. To solve this problem, a plurality of dome switches 10 are installed before the PCB 11 is cut. The manufacturing time is also shortened by soldering on the PCB base original plate on which the circuit pattern 12 is formed.

On the other hand, a look at the dome switch disclosed in Registered Patent Publication No. 10-1296835 (registered on August 08, 2013) "PBC dome switch and PBC dome switch mass manufacturing method" cited as a prior document in this application with reference to FIG. 3 , The PCB dome switch 100 has a simpler configuration than the combined configuration of the dome switch 10 and the PCB 11 on which the dome switch 10 is mounted by soldering the PCB and the dome switch to implement the same function. As a dome switch in an integrated form, the individual PCB part 110, the metal dome 120, the cover sheet 130, and the insulating sheet 140 are provided.

The individual PCB unit 110 is a circuit board having a predetermined size as an individual unit mounted on an electronic device, and a circuit pattern 111 designed to implement each function of the electronic device is formed on the upper surface, and the circuit The pattern 111 includes a first electrode 112 and a second electrode 113 that are separated and disposed to be electrically spaced apart from each other. Here, the circuit pattern 111 including the first electrode 112 and the second electrode 113 is electrically connected to the first electrode 112 and the second electrode 113 by the metal dome 120 The circuit is constructed so that the circuit is designed to generate an electrical input signal.

The metal dome 120, as shown in FIG. 3A, is mounted on the upper portion of the individual PCB unit 110, is formed of a hemispherical metal material, and is pressed by external pressure while pressing the first electrode 112 and the second electrode ( 113) as a component that selectively connects the first electrode 112 and the second electrode 113 while simultaneously contacting the first electrode 112 and the second electrode 113 to electrically connect the first electrode 112 and the second electrode 113 with elastic restoring force As shown in FIG. 3B, it is formed of the material provided, and the inner surface is in contact with the first electrode 112 and the second electrode 113 while being pressed downward by the user's pressing force, and when the pressing force is released, it returns to its original position by the elastic restoring force. It works to return.

The cover sheet 130 includes an upper portion of the metal dome 120 so that the positions of the metal dome 120 seated on the first electrode 112 and the second electrode 113 of the individual PCB unit 110 are fixed. As a component that is adhered to the upper surface of the individual PCB unit 110 in a covering form, an adhesive member is formed on the lower surface, and the upper surface of the metal dome 120 and the individual PCB unit 110 are formed by the adhesive force of the adhesive member. The metal dome 120 can be fixed on the individual PCB unit 110 by being in close contact with the upper surface of the metal dome 120.

The insulating sheet 140 is disposed between the metal dome 120 and at least one of the first electrode 112 or the second electrode 113 of the individual PCB unit 110 to provide the first electrode 112 or the second electrode. As a component that electrically separates the electrode 113 from the metal dome 120, a structure in which the first electrode 112 and the second electrode 113 and the metal dome 120 are mutually disposed as shown in FIG. 3C Selectively insulates each component according to the function.

Here, in the insulating sheet 140, a round portion having a shape corresponding to the inner circumferential surface of the metal dome 120 is formed to protrude upward, so that the metal dome 120 is inserted into the round portion 142, and the metal dome 120 ) Can be fixed to the seated state without flowing on the individual PCB unit 110.

Registered Patent Publication No. 10-1296835 (registered on Aug. 08, 2013) "PBC dome switch and PCB dome switch mass manufacturing method"

However, as electronic devices using a printed circuit board equipped with a dome switch become thinner and smaller, the printed circuit board is also becoming thinner and smaller, and when the dome switch is reciprocated, the dome switch is applied to the mounted part. Since the pressure also increases, the possibility of peeling is increasing. In particular, in the process of forming several dome switches on a single printed circuit board, if there is damage to the adhesive surface in the cutting process to separate each dome switch, the defect rate due to peeling can be further increased, and at least its lifespan is reduced. do. That is, the durability of the product decreases.

Accordingly, an object of the present invention is to provide a printed circuit board equipped with a dome switch and a method of manufacturing the same, capable of increasing reliability and durability by suppressing peeling defects of each layer while enabling mass production.

In a preferred embodiment of the present invention, in a printed circuit board equipped with a plurality of dome switches as a printed circuit board used in a portable device, the original plate base made of a copper clad laminate in which copper foil on which a circuit pattern is formed is laminated, and the original plate base An upper electrode layer on which an electrode wire connected to the circuit pattern is formed on an upper portion of the disk base, a lower electrode layer on which an electrode wire connected to the circuit pattern is formed on a lower portion of the disk base, and the upper electrode layer and the lower electrode layer through the disk base frame A via contact connecting the metal wiring of, a lower protective layer covering the via contact and the lower electrode layer with an insulating material, and an electrode wiring formed on the upper electrode layer, wherein the first wiring and the second wiring are electrically separated from each other , An upper protective layer covering the via contact and the upper electrode layer with an insulating material and exposing the first and second wires spaced apart from each other, and the dome switch on the first wire and the second wire. A dome guide sheet provided with a dome guide hole to be formed, and when the dome guide hole is seated and pressed by external pressure, the first electrode 13a and the second electrode 13b are connected, and when the external pressure is removed, the A metal dome separating the first electrode 13a and the second electrode 13b, and a cover sheet covering the dome guide sheet and the upper surface of the metal dome from the outside, wherein the dome guide sheet Characterized in that the outer edge of the metal dome is in close contact with the stepped portion of the dome guide sheet by forming a step in which the inside of the hole is thin and the outside of the dome guide hole is thickly formed on at least a part of the circumference of the dome guide hole. A printed circuit board equipped with a dome switch is provided.

In a preferred embodiment of the present invention, in the above-described embodiment, the printed circuit board equipped with the dome switch further includes a knob attached to the center of the metal dome, and the cover sheet includes the dome guide sheet and the knob. It provides a dome switch mounted printed circuit board, characterized in that covering the upper surface of the from the outside.

In a preferred embodiment of the present invention, in the above-described embodiment, the cover sheet is attached to the dome guide sheet by an adhesive layer having thermosetting and thermoplastic properties, and the adhesive layer has a thickness ranging from 0.010 mm to 0.050 mm. It provides a dome switch mounted printed circuit board, characterized in that formed of.

In a preferred embodiment of the present invention, in the above-described embodiment, the dome guide sheet is formed of polyimide containing Kapton, and is formed in a thickness range of 0.120 mm to 0.250 mm. Provide a circuit board.

In a preferred embodiment of the present invention, in a method of manufacturing a printed circuit board equipped with a plurality of dome switches as a printed circuit board used in a portable device, an original base made of a copper clad laminate in which a copper foil having a circuit pattern is laminated is used. Preparing and forming an upper electrode layer on which an electrode wiring connected to the circuit pattern is formed on an upper portion of the original plate base, and forming an electrode wiring connected to the circuit pattern on a lower portion of the original plate base to form a lower electrode layer And forming an upper electrode layer by forming an electrode wire including a first wire and a second wire connected to the circuit pattern and spaced apart from each other on an upper portion of the original plate base, and penetrating the original plate base frame. Forming a via contact connecting the upper electrode layer and the metal wiring of the lower electrode layer; forming a lower protective layer by attaching an insulating material to the surface of the lower electrode with an adhesive; and forming a lower protective layer on the surface of the upper electrode Forming an upper protective layer by attaching an insulating material to which the first wiring and the second wiring are exposed with an adhesive, and on the upper protective layer, on the first wiring and on the second wiring. Attaching a dome guide sheet having at least two dome guide holes in which the dome switch is to be formed with an adhesive, and when pressed by external pressure to each of the dome guide holes, the first electrode 13a and the second electrode ( 13b) and when the external pressure is removed, mounting a metal dome separating the first electrode 13a and the second electrode 13b, and attaching the dome guide sheet and the upper surface of the metal dome to the outside. A step of attaching a cover sheet covering from the dome with an adhesive, wherein the dome guide sheet has a small thickness inside the dome guide hole and a step formed thick outside the dome guide hole at least a part of the circumference of the dome guide hole. A dome switch mounted printed circuit characterized in that the outer edge of the metal dome is in close contact with the stepped portion of the dome guide sheet A method of manufacturing a substrate is provided.

In a preferred embodiment of the present invention, in the above-described embodiment, before attaching the cover sheet, the method further comprises attaching a knob to the center of the metal dome. Provides a manufacturing method.

In a preferred embodiment of the present invention, in the above-described embodiment, the cover sheet is attached to the dome guide sheet by an adhesive layer having thermosetting and thermoplastic properties in a thickness range of 0.010 mm to 0.050 mm. It provides a method of manufacturing a printed circuit board equipped with a dome switch.

In a preferred embodiment of the present invention, in the above-described embodiment, the dome guide sheet is a polyimide containing Kapton, and is formed in a thickness range of 0.120 mm to 0.250 mm. It provides a method of manufacturing.

In a preferred embodiment of the present invention, in the above-described embodiment, in each of the attaching steps, a dome switch, characterized in that the adhesive having thermosetting and thermoplastic properties is applied and attached in a thickness range of 0.010mm to 0.035mm. A method of manufacturing a mounted printed circuit board is provided.

In another preferred embodiment of the present invention, the dome switch-mounted printed circuit board includes a polyimide having a thickness of 0.007 mm to 0.035 mm, and a thermosetting and thermoplasticity having a thickness of 0.010 mm to 0.035 mm on top of the polyimide. A lower protective layer composed of an adhesive of, a lower electrode layer made of a copper plate having a thickness of 0.015 mm to 0.02 mm on an upper portion of the lower protective layer 220, and a thickness of 0.04 mm to 0.06 mm in the center of the lower electrode layer A disk base in which copper is laminated in a thickness range of 0.017 mm to 0.035 mm on both sides of the FR-4 and FCCL of the range, and an upper electrode layer made of a copper plate in a thickness range of 0.015 mm to 0.02 mm on the top of the disk base. , An upper protective layer composed of a polyimine having a thickness of 0.007mm to 0.035mm on top of the upper electrode layer with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.035mm, and the upper protective layer. A dome guide sheet consisting of a kapton having a thickness ranging from 0.120 mm to 0.250 mm, with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.025 mm to 0.040 mm on the top, and 0.010 on the top of the dome guide sheet. An adhesive layer consisting of a thermosetting and thermoplastic adhesive in a thickness range of mm to 0.050mm, and a thermosetting and thermoplastic adhesive having a thickness in the range of 0.010mm to 0.035mm on top of the adhesive layer, and a thickness range of 0.010mm to 0.035mm thereon It provides a dome switch mounted printed circuit board, characterized in that consisting of a cover sheet made of polyimide and a method of manufacturing the same.

According to the present invention described above, the durability and reliability of the product can be improved by preventing peeling by maintaining the adhesive force of each layer while manufacturing a dome switch in large quantities or forming a plurality of dome switches on one printed circuit board at once. There is an effect.

Specific features of the present application and effects obtained thereby will be described in more detail in the detailed description to be described later.

The accompanying drawings are intended to help to more easily understand the principles of the embodiments along with a detailed description of the spirit and scope of the present invention, and are incorporated herein to form a part of the present specification.
The drawings are not drawn in proportion to the actual scale, but are merely illustrative to aid understanding of the present invention, and may be shown by emphasizing specific portions to aid such understanding.
In addition, the same reference numerals in the drawings may indicate the same or similar constituent elements or alternative constituent elements. That is, components to which the same reference numerals are assigned may be equivalently exchanged or replaced with each other.
1 is an exploded perspective view showing the configuration of a general dome switch according to the prior art.
2 is an exploded perspective view illustrating a configuration in which a dome switch is mounted on a printed circuit board according to the prior art.
3 is a diagram illustrating a detailed structure and operation process of a dome switch according to the prior art.
4 is a partial cross-sectional view illustrating a dome switch portion of a printed circuit board equipped with a dome switch according to an exemplary embodiment of the present invention.
5 is a cross-sectional view illustrating a method of manufacturing a printed circuit board equipped with a dome switch according to an exemplary embodiment of the present invention.

The present invention may be variously changed and implemented in various embodiments, and the following description will be described in detail by illustrating specific configurations and features as one of such various embodiments to aid understanding of the present invention. It should be noted that it is not intended to limit the spirit and scope of the present invention to the exemplary matters, and all modifications, equivalents, and substitutes of the detailed exemplary matters are included in the spirit and scope of the present invention.

In the following description, terms such as “upper”, “lower”, “middle” may be used to distinguish one or more of the same constituent elements from other constituent elements, but different functions, configurations, and roles depending on where each is placed. You can also do it.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it is directly connected to or may be connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

In addition, if the two components are "adjacent" to each other, they may be in direct contact with each other (ie, directly adjacent to each other) at least in place or may be separated from each other by a very small distance.

Boundary values are included in the range for physical dimensions. For example, the range of the parameter y from a to b is read as a≤y≤b. A parameter y with a value of at least c is read as c≦y, and a parameter y with a maximum value of d is read as y≦d.

Specific terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention by the terms themselves.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "include" or "have" should be understood as not precluding the possibility of existence or addition of features, numbers, steps, actions, components, parts, or combinations thereof described herein. do.

Unless otherwise defined, all terms, including technical or scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

Hereinafter, a printed circuit board equipped with a dome switch according to a preferred embodiment of the present invention will be described with reference to FIG. 4.

4 is a partial cross-sectional view illustrating a dome switch portion of a printed circuit board equipped with a dome switch according to an exemplary embodiment of the present invention.

First, a printed circuit board equipped with a dome switch according to a preferred embodiment of the present invention is a dome switch having a dome switch mounted in the printed circuit board, and compared to a conventional process of soldering the dome switch to the printed circuit board in a subsequent process, The manufacturing process is simple, and it is suitable for mass production.

The original plate base 210 according to the present invention is a copper clad laminate made of copper-insulator-copper, such as FR-4, which is a raw material for a printed circuit board (PCB) called a circular plate, or a flexible copper clad laminate (FCCL). : flexible copper clad laminate), and a copper thin film with a thickness of 0.017mm to 0.035mm is formed on the top and bottom of the insulator with a thickness ranging from 0.04mm to 0.06mm.

For this, any base for forming a conventional printed circuit board can be used.

The copper thin film is a circuit board having a predetermined size in individual units mounted on an electronic device, and a circuit pattern designed to implement each function of the electronic device is formed on the upper surface thereof.

The upper electrode layer 212 and the lower electrode layer 214 are each formed of a copper wiring board having a thickness of 0.015 mm to 0.02 mm, and in particular, the upper electrode 212 has a first electrode and a first electrode connected to one end to a circuit board formed on a copper thin film. 2 electrodes are included. The first electrode and the second electrode may be electrically connected to a part of the wiring of the upper electrode layer 212 and a part of the wiring of the lower electrode layer 214 through a via contact 330, for example, and the first electrode and A metal pad (not shown) connected to the second electrode may be formed as the first electrode and the second electrode. Here, in the copper wiring board including the first electrode and the second electrode, when the first electrode and the second electrode are electrically connected by the metal dome 320, a circuit is formed to generate an electrical input signal.

The lower protective layer 220 and the upper protective layer 230 are formed of polyimide having a thickness of 0.010 mm to 0.035 mm, respectively, and are adhesives having thermosetting and thermoplastic characteristics of a thickness of 0.007 mm to 0.035 mm. It is attached to 214 and the upper electrode layer 212.

The lower protective layer 220 and the upper protective layer 230 cover the hole-processed portion of the original base 210 to maintain water resistance with the upper electrode layer 212 and the lower electrode layer 214, and maintain the water resistance of the circuit (pattern) and It protects other imaged surfaces and prevents corrosion.

As shown in FIG. 4, the dome guide sheet 240 is provided with a dome guide hole in which a dome switch is to be seated at an upper position of the first wire and the second wire, and the inside of the dome guide hole is thin, On the outside of the dome guide hole, a thickly formed step is formed in at least a part of the circumference of the dome guide hole. The dome guide sheet is formed of polyimide including Kapton, and is preferably formed in a thickness range of 0.120mm to 0.250mm so as to withstand fatigue due to the vertical operation of the metal dome 320. In addition, the stepped portion is expressed as a "stepped portion" when positioned at the top of the dome guide sheet 240, but may be formed as a "groove" in the middle of the dome guide sheet 240. For example, the entire body of the dome guide sheet 240 acts as a support wall that supports the outer edge of the metal dome 320, which is confined in a process to be described later, so that it does not come out, and depending on the product design, the step (or groove) is It may be formed anywhere between the uppermost end and the lowermost end of the guide sheet 240.

In addition, the outer edge of the metal dome 320 to be described later is in close contact with the stepped portion of the dome guide sheet 240, and the outside of the single layer is formed thicker (higher) than the inside, so that when the metal dome 320 moves up and down, the metal dome Prevents the outer edge of (320) from being pushed out. That is, the outer edge of the metal dome 320, which is subjected to strong pressure, is arranged on a flat surface, so that the outer wall of the metal dome 320 is composed of a single layer of steps compared to the conventional which may cause peeling due to repeated vertical movement. By supporting the pressure applied to the metal dome 320, peeling of the layer on which the metal dome 320 is installed is prevented.

In addition, the dome guide hole of the dome guide sheet 240 facilitates the arrangement of the dome switches when seating the plurality of dome switches, and the accuracy of the dome seating can be improved by the step difference.

The metal dome 120, as shown in FIG. 4, is disposed along the outer edge step of the dome guide hole of the dome guide sheet 240, is formed of a hemispherical metal material, and is pressed by external pressure while pressing the first electrode and the first electrode. 2 Selectively connect the electrodes. In other words, it is made of a material having an elastic restoring force so that the first electrode and the second electrode can be electrically connected while being pressed by the pressure applied from the outside while simultaneously contacting the first electrode and the second electrode. While being pressed downward, the inner surface contacts the first electrode and the second electrode, and when the pressure is released, it operates to return to the original position by the elastic restoring force.

The adhesive layer 250 is made of a thermosetting and thermoplastic adhesive having a thickness of 0.010mm to 0.050mm, and by attaching the cover sheet 260 and the dome guide sheet 240 to be described later to maintain its tightness, It serves to cushion the shock. The adhesive layer 250 has a thickness sufficiently thick to prevent the cover sheet 260 on the top of the metal dome 320 from peeling from the pressure applied to the metal dome 320 that repeatedly operates up and down, for example, 0.010mm to 0.050 It is preferably formed to a thickness of mm.

The knob 310 is disposed in the center of the metal dome 320 so that the pressure applied from the outside is concentrated in the center of the metal dome 320 to facilitate operation of the dome switch. That is, compared to pressing the metal dome 320 directly, it can be operated with a small force.

The cover sheet 260 covers the top of the metal dome 320 so that the positions of the metal dome 120 mounted on the first electrode and the second electrode are fixed, and the dome guide sheet through the adhesive layer 250 It is adhered to the upper portion of the (240) and the knob (310). This cover sheet may be formed of a polyimide having a thickness of 0.010 mm to 0.035 mm that is in contact with the contact layer 250 by a thermosetting and thermoplastic adhesive having a thickness of 0.010 mm to 0.035 mm, and the position of the knob 310 is set. And, it prevents the separation of the knob 310, and strengthens the adhesion with the contact layer 250.

Due to the above-described structure, it is easy to mass-produce a plurality of dome switches or to form a plurality of dome switches within one substrate, and is effective in preventing the peeling of each layer, especially the layers adjacent to the metal dome 320. And, by adjusting the thicknesses described above, it is possible to enhance the adhesive force while suppressing curling of the printed circuit board on which the dome switch is mounted.

Hereinafter, a method of manufacturing a printed circuit board equipped with a dome switch according to an exemplary embodiment of the present invention will be described with reference to FIGS. 3 and 4 with a focus on FIG. 5.

5 is a cross-sectional view illustrating a method of manufacturing a printed circuit board equipped with a dome switch according to an exemplary embodiment of the present invention. In FIG. 5, in order to clarify the material and thickness range of each layer, which is one of the main features of the present invention, the focus is shown, and the knob 310, the metal dome 320, and the step portion ( 340) is omitted, but of course it is included.

First, the original base 210 made of a copper-insulator-copper copper clad laminate or a flexible copper clad laminate (FCCL), such as FR-4, which is a raw material of a printed circuit board (PCB). ) To prepare.

In the disk base 210, a copper thin film having a thickness of 0.017 mm to 0.035 mm is formed on the upper and lower portions of an insulator having a thickness of 0.04 mm to 0.06 mm, respectively.

Thereafter, as a circuit board having a predetermined size as an individual unit mounted on an electronic device on a copper thin film, a circuit pattern designed to implement each function of the electronic device is formed on the upper surface.

Copper wiring boards having a thickness of 0.015 mm to 0.02 mm were plated on the upper and lower portions of the copper thin film on which the circuit pattern was formed, respectively, to form the upper electrode layer 212 and the lower electrode layer 214, and the upper electrode layer 212 was formed of copper. The circuit board formed on the thin film is patterned with a copper wiring board including a first electrode and a second electrode connected to one end. The upper electrode layer 212 and the lower electrode layer 214 may be formed on the copper thin film of the original plate base 210 in another embodiment.

At this time, a via contact 330 electrically connecting a part of the wiring of the upper electrode layer 212 and a part of the wiring of the lower electrode layer 214 is formed, and the upper electrode layer 212 electrically connected to the via contact 330 ) On the copper wiring board (metal pad) may be used as the first electrode and the second electrode.

Here, in the copper wiring board including the first electrode and the second electrode, when the first electrode and the second electrode are electrically connected by the metal dome 320, a circuit is formed to generate an electrical input signal.

Subsequently, polyimide having a thickness of 0.010 mm to 0.035 mm, respectively, was attached to the lower electrode layer 214 and the upper electrode layer 212 with an adhesive having thermosetting and thermoplastic characteristics of a thickness of 0.007 mm to 0.035 mm, respectively, and the lower protective layer 220 and an upper protective layer 230 are formed.

In the process of forming the lower protective layer 220 and the upper protective layer 230, after forming the lower protective layer 220, the upper protective layer 230 may be formed, or may be performed simultaneously. In addition, the lower protective layer 220 may be formed of thermally curable photo solder resist (PSR).

Next, a dome guide sheet 240 made of polyimide such as Kapton is attached with an adhesive having a thickness of 0.025 mm to 0.040 mm. The dome guide sheet 240 is provided with a dome guide hole in which the dome switch is to be seated in the upper position of the first wire and the second wire, and the inside of the dome guide hole is thin, and the outside of the dome guide hole is formed thick. A step is formed in at least a part of the circumference of the dome guide hole. The dome guide sheet is formed of polyimide including Kapton, and is preferably formed in a thickness range of 0.120mm to 0.250mm so as to withstand fatigue due to the vertical operation of the metal dome 320.

In addition, the outer edge of the metal dome 320 to be described later is in close contact with the stepped portion of the dome guide sheet 240, and the outside of the single layer is formed thicker (higher) than the inside, so that when the metal dome 320 moves up and down, the metal dome Prevents the outer edge of (320) from being pushed out. That is, the outer edge of the metal dome 320, which is subjected to strong pressure, is arranged on a flat surface, so that the outer wall of the metal dome 320 is composed of a single layer of steps compared to the conventional which may cause peeling due to repeated vertical movement. By supporting the pressure applied to the metal dome 320, peeling of the layer on which the metal dome 320 is installed is prevented.

In addition, the dome guide hole of the dome guide sheet 240 facilitates the arrangement of the dome switches when seating the plurality of dome switches, and the accuracy of the dome seating can be improved by the step difference.

Thereafter, a metal dome 120 formed of a hemispherical metal material and selectively connecting the first electrode and the second electrode while being pressed by external pressure, as shown in FIG. 4, is provided as a dome guide of the dome guide sheet 240. It is placed along the edge of the hole.

Subsequently, after the knob 310 is disposed in the center of the metal dome 320, an adhesive layer 250 made of a thermosetting and thermoplastic adhesive having a thickness of 0.010 mm to 0.050 mm is formed. The adhesive layer 250 serves to maintain the adhesive force by attaching the cover sheet 260 and the dome guide sheet 240 to be described later, and buffer an impact applied from the outside. The adhesive layer 250 has a thickness sufficiently thick to prevent the cover sheet 260 on the top of the metal dome 320 from peeling from the pressure applied to the metal dome 320 that repeatedly operates up and down, for example, 0.010mm to 0.050 It is preferably formed to a thickness of mm.

Thereafter, the dome guide sheet 240 and the knob through the adhesive layer 250 in the form of covering the upper portion of the metal dome 320 so that the positions of the metal dome 120 seated on the first electrode and the second electrode are fixed. A cover sheet 260 made of polyimide is attached to the top of 310 by a thermosetting and thermoplastic adhesive having a thickness of 0.010 mm to 0.035 mm. This cover sheet sets the position of the knob 310, prevents the knob 310 from being dislodged, and strengthens adhesion with the contact layer 250. At this time, it is preferable that the polyimide has a thickness range of 0.010mm to 0.035mm.

By this manufacturing method, it is easy to mass-produce a plurality of dome switches or to form a plurality of dome switches in one substrate, and is effective in preventing the peeling of each layer, especially the layers adjacent to the metal dome 320. And, by adjusting the thicknesses described above, it is possible to enhance the adhesive force while suppressing curling of the printed circuit board on which the dome switch is mounted.

While specific embodiments have been shown and described herein, those skilled in the art will understand that various alternatives and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Accordingly, it is intended that the present invention be limited only by the claims and their equivalents.

10: dome switch
11: printed circuit board (PCB)
12: circuit pattern
13: electrode plate
14: insulation sheet
15, 320: metal dome
16, 250: dome guide sheet
17, 260: cover sheet
210: original plate base
212: upper electrode layer
214: lower electrode layer
220: lower protective layer
230: upper protective layer
240: insulation sheet
250: adhesive layer
310: knob
330: via contact (switch electrode)

Claims (7)

A printed circuit board used in a portable device, wherein a printed circuit board equipped with a plurality of dome switches,
A disc base made of a copper clad laminate in which a copper foil with a circuit pattern is laminated,
An upper electrode layer including an electrode wiring connected to the circuit pattern and including a first electrode and a second electrode on the disk base,
A lower electrode layer on which an electrode wiring connected to the circuit pattern is formed under the original base,
A via contact penetrating the original base frame and connecting the metal wires of the upper electrode layer and the lower electrode layer;
A lower protective layer covering the via contact and the lower electrode layer with an insulating material,
An electrode wiring formed on the upper electrode layer, the first wiring and the second wiring electrically separated from each other,
An upper protective layer covering the via contact and the upper electrode layer with an insulating material and exposing the first wiring and the second wiring spaced apart from each other;
A dome guide sheet in which a dome guide hole in which the dome switch is to be formed is provided above the first wire and the second wire,
It is seated in the dome guide hole, and when pressed by external pressure, the first electrode 13a and the second electrode 13b are connected, and when the external pressure is removed, the first electrode 13a and the second electrode 13b ) To separate the metal dome,
It includes a cover sheet covering the dome guide sheet and the upper surface of the metal dome from the outside,
In the dome guide sheet, a step formed with a thin inside of the dome guide hole and a thick outside of the dome guide hole is formed on at least a part of the circumference of the dome guide hole, so that the outer edge of the metal dome is formed on the stepped portion of the dome guide sheet. Closely adhered,
The lower protective layer is composed of a polyimide having a thickness ranging from 0.007mm to 0.035mm, and a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.035mm on the top of the polyimide,
The lower electrode layer is made of a copper plate having a thickness ranging from 0.015 mm to 0.02 mm on the upper protective layer,
In the base of the disc, copper is laminated in a thickness range of 0.017 mm to 0.035 mm on both sides of FR-4 and FCCL having a thickness ranging from 0.04 mm to 0.06 mm in the center and on the lower electrode layer,
The upper electrode layer is made of a copper plate having a thickness of 0.015 mm to 0.02 mm on the upper portion of the original plate base,
The upper protective layer is composed of a polyimide having a thickness of 0.007mm to 0.035mm on the top of the upper electrode layer with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.035mm,
The dome guide sheet is composed of a kapton having a thickness of 0.120 mm to 0.250 mm on the top of the upper protective layer with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.025 mm to 0.040 mm,
An adhesive layer made of a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.050mm is provided on the top of the dome guide sheet,
The cover sheet is a printed circuit equipped with a dome switch, characterized in that the cover sheet is made of polyimide having a thickness ranging from 0.010 mm to 0.035 mm with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010 mm to 0.035 mm on the upper portion of the adhesive layer. Board.
The method of claim 1,
The dome switch-mounted printed circuit board,
Further comprising a knob attached to the center of the metal dome,
The cover sheet is characterized in that to cover the upper surface of the dome guide sheet and the knob from the outside.
Printed circuit board with dome switch.
The method according to claim 1 or 2,
The dome guide sheet is formed of polyimide containing Kapton, and is formed in a thickness range of 0.120 mm to 0.250 mm.
delete In the method of manufacturing a printed circuit board equipped with a plurality of dome switches as a printed circuit board used in a portable device,
Preparing an original plate base made of a copper clad laminate in which a copper foil having a circuit pattern formed thereon is stacked,
Forming an upper electrode layer including an electrode wiring connected to the circuit pattern and including a first electrode and a second electrode on an upper portion of the disk base; and
Forming a lower electrode layer by forming an electrode wiring connected to the circuit pattern under the original base,
Forming an upper electrode layer by forming an electrode wire including a first wire and a second wire connected to the circuit pattern and spaced apart from each other on an upper portion of the original plate base; and
Forming a via contact passing through the original base frame and connecting the metal wiring of the upper electrode layer and the lower electrode layer;
Forming a lower protective layer by attaching an insulating material to the surface of the lower electrode with an adhesive,
Forming an upper protective layer by attaching an insulating material to which the first wiring and the second wiring are exposed to the surface of the upper electrode with an adhesive, and
Attaching a dome guide sheet having at least two dome guide holes in which the dome switch is to be formed on the first wire and the second wire with an adhesive on the upper protective layer,
In each of the dome guide holes, when pressed by external pressure, the first electrode 13a and the second electrode 13b are connected, and when the external pressure is removed, the first electrode 13a and the second electrode 13b Seating a metal dome separating it,
Including the step of attaching the dome guide sheet and the cover sheet covering the upper surface of the metal dome from the outside by an adhesive,
In the dome guide sheet, a step formed with a thin inside of the dome guide hole and a thick outside of the dome guide hole is formed on at least a part of the circumference of the dome guide hole, so that the outer edge of the metal dome is formed on the stepped portion of the dome guide sheet. Closely adhered,
The lower protective layer is composed of a polyimide having a thickness ranging from 0.007mm to 0.035mm, and a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.035mm on the top of the polyimide,
The lower electrode layer is made of a copper plate having a thickness ranging from 0.015 mm to 0.02 mm on the lower protective layer 220,
In the base of the disc, copper is laminated in a thickness range of 0.017 mm to 0.035 mm on both sides of FR-4 and FCCL having a thickness ranging from 0.04 mm to 0.06 mm in the center and on the lower electrode layer,
The upper electrode layer is made of a copper plate having a thickness ranging from 0.015 mm to 0.02 mm on the upper portion of the original plate base,
The upper protective layer is composed of a polyimide having a thickness of 0.007mm to 0.035mm on the top of the upper electrode layer with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.035mm,
The dome guide sheet is composed of a kapton having a thickness of 0.120 mm to 0.250 mm on the top of the upper protective layer with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.025 mm to 0.040 mm,
An adhesive layer made of a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010mm to 0.050mm is provided on the top of the dome guide sheet,
The cover sheet is a printed circuit equipped with a dome switch, characterized in that the cover sheet is made of polyimide having a thickness ranging from 0.010 mm to 0.035 mm with a thermosetting and thermoplastic adhesive having a thickness ranging from 0.010 mm to 0.035 mm on the upper portion of the adhesive layer. Substrate manufacturing method.
The method of claim 5,
Before attaching the cover sheet, the method of manufacturing a printed circuit board equipped with a dome switch, further comprising attaching a knob to the center of the metal dome.
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