KR20130038690A - The method for manufacturing the radiant heat circuit board unified blanket and the patterned mask for manufacturing the same - Google Patents

Abstract

PURPOSE: A manufacturing method of blanket integrated type heat radiation circuit board and a pattern mask used for the same are provided to improve heat radiating property by directly delivering heat to a chassis through directly connecting a heat radiating circuit board to the lateral surface of the chassis. CONSTITUTION: A heat radiation circuit board in which a first side and a second side are formed is prepared. The first and second sides of the heat radiation circuit board are curved. A mask(200) exposing a pad on the first side of the heat radiation circuit board is formed. The pattern mask comprises a pad hole(210) exposing the pad and a substrate hole(220) exposing a bending region(130a). A solder(151) is coated on the pad. A light emitting device is adhered to the solder.

Description

The method for manufacturing the radiant heat circuit board unified blanket and the patterned mask for manufacturing the same}

The present invention relates to a method for manufacturing a blanket integrated heat dissipation circuit board.

Liquid crystal display (LCD) is a display device in which the liquid crystal is inclined according to the intensity of the electric field formed by the upper and lower electrodes, and displays an image by selectively transmitting the light emitted from the lower backlight according to the inclination degree. .

The liquid crystal display is a flat panel display that is widely used because of low power consumption and low power consumption.

The backlight of the liquid crystal display device is a light source for irradiating light to the rear of the liquid crystal panel, and a complex including a power supply circuit for driving the light source and an integral part to form a uniform plane light is called a backlight unit (BLU). do. In the backlight unit, a light source device such as a light emitting diode (LED) is mounted on a printed circuit board. The printed circuit board uses a metal material that can withstand the heat emitted by the light source element.

However, if the heat generated from the light source device is not released, the light source device may be destroyed or the life may be shortened.

FIG. 1 illustrates a cross-sectional view of a heat dissipation circuit board 10 and a blanket 40 manufactured according to the related art in a chassis 50 that is a light guiding passage of a backlight unit.

Referring to FIG. 1, the heat dissipation circuit board 10 and the blanket 40 for fixing it to the chassis 50 are separately manufactured and bonded using the adhesive layer 20, and the chassis 40 used as the light guiding passage. ) Using an adhesive layer (30).

In this case, the blanket 40 has a predetermined thickness, extends horizontally from the side wall of the chassis 50, is spaced apart from the side wall of the chassis 50 by a predetermined distance, and is bent at a first angle θ 1, and the chassis ( 50 is bent again at the bottom surface 110a and the second angle θ2. When the first angle θ1 of the blanket 40 is 0 to 90 degrees, the bezel of the chassis 50 increases in the heat dissipation circuit board 10, and the first angle θ1 is 90 to 270 degrees. In this case, when the thickness of the backlight unit is increased and the first angle θ1 is 270 to 360, a problem of obstructing an optical path of the light emitting diode occurs.

In addition, when the second angle θ1 formed between the side surface 110b and the bottom surface of the blanket 40 is 90 to 270 degrees, when the thickness of the backlight unit is increased and the second angle θ1 is 270 to 360 degrees, There was a problem of increasing bezel size.

Thus, a blanket integrated PCB has been proposed to reduce bezel size.

However, in the case of a blanket integrated PCB, a new manufacturing method for bending the PCB itself and mounting the light emitting device package is needed.

The embodiment provides a method of manufacturing a pattern mask and a blanket integrated heat dissipation circuit board having a new structure.

According to an embodiment of the present invention, there is provided a method of forming a heat dissipation circuit board having a first surface and a second surface extending from the first surface, bending the first and second surfaces of the heat dissipation circuit board, and Forming a mask exposing the second surface and the pad on the first surface, applying a solder on the pad by the mask, and attaching a light emitting device on the solder. Provide a method.

On the other hand, the embodiment is a pattern mask for applying solder to a bent printed circuit board mounting a light emitting device, the pattern mask is a pad hole for exposing a pad formed on the first surface of the printed circuit board, and the And a substrate hole exposing the second surface bent from one surface.

According to the present invention, the heat dissipation circuit board to which the light emitting element is attached is formed in a bent shape, and the heat dissipation circuit board is directly bonded to the side of the chassis so that the chassis and the heat dissipation circuit board are combined without the bezel. In addition, by directly transferring heat from the heat dissipation circuit board to the chassis, heat dissipation is improved, and a space in which the light guide plate is formed can be expanded because no bezel is required.

In addition, when the bent heat radiation circuit board is formed, it is possible to prevent damage to the light emitting device due to bending by performing soldering after line bending.

In addition, by using a pattern mask that opens the bent surface when forming the bent heat radiation circuit board, it is possible to reduce the thickness of the pattern mask than when soldering after bending.

In addition, defects may be reduced by forming guide protrusions around the openings while forming openings that open the bent surface in the pattern mask to prevent solder from flowing chemicals.

1 is a cross-sectional view of a conventional blanket integrated heat dissipation circuit board and chassis structure.
2 is a cross-sectional view of a blanket integrated heat dissipation circuit board and a chassis structure including the same according to the present invention.
3 is a top view of the blanket integrated heat dissipation circuit board shown in FIG. 2.
4 to 8 illustrate a process of manufacturing the heat dissipation circuit board of FIG. 2 according to one method.
9 and 10 illustrate a process of manufacturing the heat dissipation circuit board of FIG. 2 according to another method.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise.

In order to clearly illustrate the present invention in the drawings, thicknesses are enlarged in order to clearly illustrate various layers and regions, and parts not related to the description are omitted, and like parts are denoted by similar reference numerals throughout the specification .

Whenever a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle.

The present invention provides a blanket integrated heat dissipation circuit board, the heat dissipation circuit board configured to be in direct contact with the chassis.

Hereinafter, a heat dissipation circuit board according to a first embodiment of the present invention will be described with reference to FIGS. 2 and 3.

2 is a cross-sectional view of a blanket integrated heat dissipation circuit board and a chassis structure including the same according to the first embodiment of the present invention, and FIG. 3 is a top view of the blanket integrated heat dissipation circuit board shown in FIG. 2.

2 and 3, the chassis structure 100 of the present invention includes a blanket integrated heat dissipation circuit board, an adhesive layer 120, and a chassis 110.

The chassis 110 may be a bottom chassis of a display device including a backlight unit such as a liquid crystal display, and may be formed to be perpendicular to the bottom surface 110a to accommodate the light guide plate 180 and the display panel therein. 110b.

The chassis 110 may be formed of a metal having high thermal conductivity, and may be formed of an alloy including copper or aluminum.

The light guide plate 180 diffuses the light provided from the light emitting device 170 to serve as a surface light source. The light guide plate 180 is made of a transparent material, for example, acrylic resin-based such as polymethyl metaacrylate (PMMA), polyethylene terephthlate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphthalate (PEN). It may include one of the resins.

The blanket integrated heat dissipation circuit board includes a support substrate 130 made of an alloy including copper, aluminum, nickel, or the like having high heat conductivity and excellent heat dissipation.

An insulating layer 140 including an epoxy resin or a polyimide resin is formed on the support substrate 130, and a pattern 150 formed by patterning a copper foil layer on the insulating layer 140, specifically, Pads 150a and 150b or a circuit pattern 150c are formed.

In this case, the pads 150a and 150b are electrically connected to the electrode pad 150a and the plurality of electrode pads 150a of the light emitting device 170 mounted thereon to transmit external power. It may be a connector pad 150c, and the pads 150a and 150b may be exposed by the solder resist 160.

On the other hand, as shown in Figure 3, the heat dissipation circuit board is composed of two bent regions (130a, 130b), one bent region (130a) has a first width (X), the other bent region (130b) is a second It has a width (Y).

The first width X and the second width Y may be equal to each other, but are not limited thereto.

Pads 150a and 150b and a circuit pattern 150c are formed to mount the light emitting device 170 in one of the two bent regions 130a and 130b.

That is, the pads 150a and 150b and the circuit pattern 150c are formed in one bent region 130b, and the metals are formed in the bent region 150b where the pads 150a and 150b and the circuit pattern 150c are formed. The insulating layer 140 is formed on the support substrate 130.

In this case, a device region A on which a plurality of light emitting elements 170, for example, a light emitting diode is mounted, is defined on the electrode pad 150a of the one bent region 130b.

As shown in FIG. 3, both the insulating layer 140 and the pattern 150 may be formed in only one of the two bent regions 130a and 130b, and the other bent region 130a may be a dummy region. In contrast, the insulating layer 140 is formed in both of the bent regions 130a and 130b, the electrode pad 150a of the light emitting device 170 is formed in one of the bent regions 130b, and the other bent region 130a. A circuit pattern 150c may be formed in the light emitting device 170 to transmit a signal to each light emitting device 170.

Meanwhile, in the bent regions 130a and 130b, the bent region 130a, in which the light emitting element 170 is not mounted, is in contact with the bottom surface 110a of the chassis 110, and an element region for mounting the light emitting element 170 is provided. A bent region 130b in which (A) is defined is mounted in contact with the side surface 110b of the chassis 110.

In this case, the second width Y of the bent region 130b may have the same height as that of the side surface 110b of the chassis 110, but may be lower than the side surface 110b of the chassis 110.

The chassis 110 and the heat dissipation circuit board may be fixed by applying an adhesive layer 120 between the bottom surface 110a of the chassis 110 and the heat dissipation circuit board.

The adhesive layer 120 uses a thermal interface material (TIM) such as thermal grease or thermal compound having high thermal conductivity and excellent adhesion.

As such, while forming a bent heat radiating circuit board without a separate blanket, the heat radiating circuit board is formed in an L shape and attached to be in close contact with the side surfaces 110b of the chassis 110. ) Is not formed between the light emitting device 170 and the heat dissipation property by directly transferring heat to the chassis 110.

In addition, the area occupied by the blanket is removed, thereby increasing the area acting as the surface light source of the backlight unit.

In the above description, the backlight unit attaching the L-shaped heat dissipation circuit board to the chassis 110 has been described. However, since the heat dissipation circuit board adopts a metal substrate, a direct circuit pattern is formed on the metal chassis 110 and the light emitting device ( A backlight unit having a structure for mounting 170 is also applicable. Hereinafter, a method of manufacturing a blanket integrated heat dissipation circuit board will be described with reference to FIGS. 4 to 8.

First, as shown in FIG. 4, a heat radiation circuit board is prepared.

The heat dissipation circuit board has two bent regions 130a and 130b defined as shown in FIG. 3 and is formed on the same plane.

The heat radiation circuit board has a circuit pattern 150 formed thereon, and a solder resist 160 is coated to cover the circuit pattern 150 except for the pad.

Next, as shown in FIG. 5, both of the bent regions 130a and 130b are bent at an angle of 90 degrees.

At this time, the bending process may be bent using a V-shaped mold or L-shaped mold.

Next, as shown in FIG. 6, a solder 151 for bonding the light emitting device 170 is applied to the pads of the bent regions 130a and 130b.

The solder 151 may be applied to the pad opened by the mask 200 through printing or the like.

In this case, the pattern mask 200 may expose the pad hole 210 exposing each pad and the substrate hole 220 exposing the bent region 130a to which the solder 151 is not applied, as shown in FIGS. 6 and 7. ).

The substrate hole 220 may be formed in a bar shape along the shape of the heat dissipation circuit board, and the pad hole 210 may be separated and formed along pads separated from each other.

Accordingly, the solder 151 may be printed and applied on the pad exposed by the pad hole 210, and the mask may also be applied when the solder 151 is applied after bending by exposing the region 130a of the bent substrate at the same time. The thickness of 200 can be reduced.

The pattern mask 200 may be formed of a metal of a thin film, and may be formed of an alloy including a metal such as aluminum and chromium.

In this case, the pad hole 210 and the substrate hole 220 having a plurality of pairs may be formed to apply the solder 151 to the plurality of substrates with one pattern mask 200.

The solder 151 may be formed of a conductive metal including tin and the like.

Next, the light emitting device 170 is attached to the solder 151 as shown in FIG. 8.

The light emitting device 170 is attached to the light emitting device 170 by placing the light emitting device 170 on the solder 151 and performing reflow while pressurizing the pad and the light emitting device 170 while alloying the components of the solder 151. Electrically and physically connected.

Meanwhile, the heat dissipation circuit board may also apply solder using the pattern mask 300 shown in FIGS. 9 and 10.

9 and 10, the pattern mask 300 according to the second exemplary embodiment may expose a plurality of pad holes 310 exposing a pad and a bent region of a substrate, like the pattern mask 200 of FIG. 8. The substrate hole 320 is included.

In this case, the pattern mask 300 includes a guide protrusion 330 protruding upward along the edge region of the substrate hole 320.

The guide protrusion 330 may be formed lower than the exposed bending region 130a.

By including the guide protrusion 330 as shown in FIGS. 9 and 10, the solder 151 may be prevented from flowing to the substrate through the substrate hole 220. The pattern mask 300 may be provided on a plurality of substrates. When applying the solder 151, the force is dispersed up and down by the formation of the guide protrusion 330 to prevent the thin pattern mask 300 from being struck by tension. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

Chassis Structure 100
Support substrate 130
Chassis 110
Light emitting element 170
Pattern mask 200, 300

Claims (13)

Forming a heat dissipation circuit board having a first surface and a second surface extending from the first surface;
Bending the first and second surfaces of the heat dissipation circuit board,
Forming a mask on the first surface of the heat dissipation circuit board and exposing a pad formed on the second surface and the first surface, and applying solder on the pad by the mask; and
Attaching a light emitting device on the solder
Method for manufacturing a heat radiation circuit board comprising a. The method of claim 1,
Forming the heat dissipation circuit board
A support substrate including the first surface and the second surface,
An insulating layer formed on the support substrate,
A circuit pattern or the pad formed on the insulating layer of the first surface, and
A method of manufacturing a heat dissipation circuit board formed to have a solder resist to expose the pad. The method of claim 2,
A method of manufacturing a heat dissipation circuit board attaching the light emitting element on the first surface. The method of claim 2,
The support substrate is a manufacturing method of a heat radiation circuit board formed of a metal substrate. The method of claim 2,
And the mask has the substrate hole exposing the second surface and the pad hole separated from each other. The method of claim 5,
And the substrate hole is formed to have a bar shape. The method according to claim 6,
A method of manufacturing a heat dissipation circuit board to form a guide protrusion surrounding the substrate hole. The method according to claim 6,
And the mask is made of aluminum. The method of claim 1,
A method of manufacturing a heat dissipation circuit board to apply solder to a plurality of heat dissipation circuit boards at the same time with the one mask. In the pattern mask for applying a solder to the bent printed circuit board mounting the light emitting element,
The pattern mask is
A pad hole exposing a pad formed on the first surface of the printed circuit board, and
A substrate hole exposing a second surface bent from the first surface
Pattern mask comprising a. The method of claim 10,
The pad holes of the pattern mask are separated from each other. The method of claim 11,
The substrate hole has a bar shape along the shape of the printed circuit board. The method of claim 10,
And a pattern protrusion protruding along an edge of the substrate hole.

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