KR101374895B1

KR101374895B1 - Side view type light emitting diode package and method for fabricating the same diode

Info

Publication number: KR101374895B1
Application number: KR1020070032038A
Authority: KR
Inventors: 김원일
Original assignee: 서울반도체 주식회사
Priority date: 2007-03-31
Filing date: 2007-03-31
Publication date: 2014-03-17
Also published as: KR20080089058A

Abstract

The present invention relates to an LED package, and provides a side emitting type LED package in which a groove filled with a liquid resin is formed on a PCB on which the LED chip is mounted so that the resin formed primarily around the LED chip has a predetermined lens shape. It is technical problem to do.

To this end, the side-emitting type LED package according to the present invention, the PCB having a groove on the upper surface; An LED chip mounted in the groove; A first molding part filled in the groove to cover the LED chip; A second molding part formed on the PCB to cover the first molding part, the second molding part being provided in a horizontal direction and a narrow upper emission surface in a vertical direction, and the horizontal side surfaces perpendicular to the upper emission surface Comprising a total internal reflection plane of the plane, the upper light emitting surface is formed with a convex curved surface symmetrical left and right in the horizontal direction.

LED, Package, Molding, Horizontal, Vertical, PCB, Groove

Description

Side emitting type LED package and its manufacturing method {SIDE VIEW TYPE LIGHT EMITTING DIODE PACKAGE AND METHOD FOR FABRICATING THE SAME DIODE}

1 is a perspective view showing a side-emitting LED package according to an embodiment of the present invention.

2 is a plan view of the side-emitting LED package shown in FIG.

3 is a cross-sectional view taken along the line II of FIG. 2;

4 is a view for explaining a manufacturing process of the side-emitting type LED package according to an embodiment of the present invention.

5 is a plan view showing a side-emitting LED package according to another embodiment of the present invention.

6 is a view for explaining a manufacturing process of the side-emitting type LED package according to another embodiment of the present invention.

10: PCB 11: Home

12, 14: electrode 20: LED chip

42: first molding part 44: second molding part

442: upper light emitting surface 443: horizontal side

The present invention relates to an LED package, and more particularly to a side-emitting type LED package.

Usually, a backlighting unit is used for illumination of a display panel such as an LCD. The backlighting unit includes an LED package used as a light source, a light guide plate for guiding light from the LED package to the display panel, and the like. The LED package is mainly installed on the under side or the side of the light guide plate. Recently, the side light type backlight unit having the LED package on the side of the light guide plate is increasing.

The LED package used in the side illumination type backlighting unit should have a small thickness and have a structure in which light is widely emitted in one axis direction and light emission is suppressed in the other axis direction perpendicular to the one axis direction. A conventional LED package developed for this purpose includes a housing including a reflector in an opening and a structure in which a part of the lead frame supports an LED chip accommodated in an opening provided with the reflector.

However, since the conventional LED package as described above requires a housing having a predetermined thickness, the entire thickness is minimized to limit the realization of a slimmed backlighting unit. In addition, it is also possible to minimize the size increase due to the housing and the lead frame There is a difficulty in consultation.

Accordingly, the present applicant has developed a side emitting type LED package in which an LED chip is mounted on a PCB having a thin thickness and a molding part of an epoxy resin is formed to cover the LED chip on the PCB. In the case of an LED package using an epoxy resin as a molding portion, heat or yellowing may occur in a portion close to the LED chip. For example, a silicon resin covering the LED chip is first formed by a dotting method, and a molding part formed of an epoxy resin is formed thereon by a transfer molding method to protect the LED chip and the LED chip on the PCB. Including, it is possible to manufacture a side-emitting LED package.

However, in the process of forming the silicone resin to cover the LED chip on the PCB, the present applicant has found that the liquid silicone resin spreads irregularly on the planar PCB, and thus the resin formed directly on the LED chip is designed in the desired lens shape It was difficult to do.

The technical problem to be achieved by the present invention, in the LED package to protect the LED chip on the PCB with a heterogeneous molding, by forming a groove filled with a liquid resin on the PCB on which the LED chip is mounted, the primary formation near the LED chip It is to provide a side-emitting type LED package and a method of manufacturing the resin so that the resin can have a predetermined lens shape.

In order to achieve the above technical problem, the side-emitting type LED package according to an embodiment of the present invention includes a PCB having a groove on the upper surface; An LED chip mounted in the groove; A first molding part filled in the groove to cover the LED chip; A second molding part is formed on the PCB so as to cover the first molding part, the second molding part being provided with a top light emitting surface wide in the horizontal direction and narrow in the vertical direction.

According to the embodiments of the present invention, the transverse side surfaces perpendicular to the upper surface of the PCB are formed in the plane total internal reflection surface. More preferably, each of the transverse sides is coplanar with each of the long sides of the PCB. In this case, the upper emission surface is formed as a convex curved surface symmetrical left and right in the horizontal direction.

In addition, the first molding part is formed of a silicon material and contains at least one phosphor. In addition, the grooves preferably have a depth such that the light emitted from the LED chip is emitted to the outside without hitting the side wall thereof.

Furthermore, it is preferable that the vicinity of the longitudinal side surface perpendicular to the upper emission surface and adjacent to the horizontal side surfaces is formed as a curved surface.

In addition, the method of manufacturing a side-emitting type LED package according to an embodiment of the present invention comprises the steps of providing a PCB with a groove formed on the upper surface, mounting the LED chip in the groove, the bonding of the mounted LED chip by a bonding wire Forming a first molding part formed in the groove to cover the LED chip, and being formed on the PCB so as to cover the first molding part, the upper light emission being wide in the horizontal direction and narrow in the vertical direction Forming a second molding part provided with a face, and performing a cutting process to form an individual package.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, and the like of the components may be exaggerated for convenience. Like numbers refer to like elements throughout.

1 is a perspective view showing a side-emitting LED package according to an embodiment of the present invention, Figure 2 is a plan view showing a side-emitting LED package shown in Figure 1, Figure 3 is a II of FIG. It is a cross section taken along.

As shown in FIGS. 1 to 3, the side-emitting type LED package 1 according to the present embodiment includes a PCB 10 having a groove 11 and an LED chip mounted inside the groove 11. 20) and light transmitting first and second molding parts 42 and 44 covering the LED chip 20. The PCB 10 has a rectangular bar shape formed in a lengthwise direction. Therefore, the upper surface of the PCB 10 is wide in the horizontal direction and narrow in the vertical direction.

First and second electrodes 12 and 14 are formed on the PCB 10 having the grooves 11. The first and second electrodes 12 and 14 are made of an insulating resin such as resin or bakelite resin By forming a metal pattern on the rods by a printing technique. The LED chip 20 is mounted inside the groove 11 of the PCB 10 and attached to the first electrode 12 and bonded to the bonding wire W with the second electrode 14. [ Lt; / RTI >

The groove 11 formed in the PCB 10 has a small depth and has a depth such that light emitted from the LED chip 20 does not hit the side wall of the groove 11 but is emitted to the outside desirable. In addition, since the filling amount is filled in the groove 11 by adjusting the amount of the sealing member (eg, silicon, hybrid, or epoxy) during dotting, even if the viscosity is low, it does not spread on the plane.

A light-transmissive first molding part 42 is formed in the groove 11 formed in the PCB 10 to cover the LED chip 20. A second molding part 44 is formed on the first molding part 42 to cover the first molding part 42. The second molding part 44 is elongated on the upper surface of the PCB 10 so that an upper light emitting surface 442 which is wide in the lateral direction and narrow in the longitudinal direction is formed at the upper end of the second molding part 44 Is formed. The second molding portion 44 includes four side surfaces perpendicular to the upper light emitting surface 442. Two lateral side surfaces 443 of the second molding portion 44 are the same as the lateral side surfaces of the PCB 10 And is formed in a plane located on a plane. At this time, the two longitudinal side surfaces 444 of the second molding part 44 are curved but may be flat.

The second molding part 44 according to the present embodiment has a structure in which the total internal reflection amount on the side is greatly increased as compared with the conventional LED package, that is, the conventional LED package having a side inclination. This is possible because the second molding portion 44 in this embodiment includes lateral sides 443 that are parallel to each other and also have a generally planar structure. The planar structure of such lateral sides 443 greatly increases the angle of light as shown in FIG. 3, which is incident on the lateral sides, as compared to the conventional LED package, The light efficiency can be greatly increased. In addition, the overall thickness of the side-emitting LED package 1 may be reduced by the structure in which the horizontal side surfaces 443 and the horizontal side surfaces of the PCB 10 are located on the same plane.

On the other hand, the first molding part 42 is formed of a silicone resin filled in the groove 11, the second molding part 44 is formed above the first molding part 42, It is formed of an epoxy resin defining one upper emitting surface 442 and the sides perpendicular to it.

The first molding part 42 of the silicone resin is formed to cover the LED chip 20 before the second molding part 44 is formed and the second molding part 44 of the epoxy resin is formed by a transfer molding method The first molding part 42 and the second molding part 42 are formed. At this time, the first molding part 42 may contain a fluorescent material capable of changing the color of light emitted from the LED chip 20. The silicone resin forming the first molding part 42 has a very small thermal change as compared with the epoxy resin. Accordingly, the first molding part 42 prevents the thermal deformation which may be caused by heat emitted from the LED chip 20. [

Here, the first molding part 42 preferably contains at least one phosphor, and light emitted from the LED chip 20 and light excited by the phosphor may be mixed to form various colors.

The upper light emitting surface 442 of the second molding part 44 is formed as a left and right symmetrical curved surface capable of increasing the amount of light from its center to both left and right sides. At this time, the upper light emitting surface 442 is preferably designed in such a way that the maximum amount of light, but may be designed in any other curved shape in consideration of the conditions of the object to be illuminated by the side-emitting type LED package (1).

The upper light emitting surface 442 constituting the curved surface can increase the amount of light from the center to both left and right sides, so that the transverse side surfaces 443 of the second molding part 44 greatly increase the total internal reflection of the light. Increasing parallel to each other is a planar structure, by which the increased amount of light is made possible by directing the upper light emitting surface 442 left and right by the curved shape of the upper light emitting surface 442.

4 is a view illustrating a manufacturing process of the above-described side-emitting type LED package 1, referring to FIG. 4, grooves 11 are formed on a single plate-shaped PCB 10 in units of columns, and the grooves (11) A plurality of LED chips 20 are mounted therein and each of the LED chips 20 is packaged from the package material 100 covered by the first molding portion 42 and the second molding portion 44. By cutting the package material 100 so that the LED chip 20 can be separated, the side-emitting type LED package 1 according to the present invention described above can be manufactured. At this time, the first molding part 42, the second molding part 44, and the lateral side surfaces of the PCB 10, which are positioned on the same plane, are cut from the package material 100.

According to a preferred embodiment of the present invention, the side-emitting LED package 1 is made of an ultra-slim structure having a thickness of about 0.2mm ~ 0.4mm, most preferably 0.3mm, the side-emitting LED package ( The length of 1) is determined to be three times or more, more preferably four times or more of the thickness.

The side-emitting type LED package 1 of the embodiment shown in FIG. 5 forms a structure in which a vicinity of a longitudinal side surface of the second molding part 44 is formed with a curved surface with a predetermined curvature. Such a structure contributes to preventing a decrease in the efficiency of light at the portion by making the curved surface 444a in the longitudinal side surface of the second molding portion 44 causing the decrease in the light efficiency.

FIG. 6 is a view illustrating a manufacturing process of a side emitting type LED package 1 according to another embodiment of the present invention. Referring to FIG. 6, grooves 11 are individually disposed on one plate-shaped PCB 10. Package material 100 in which one LED chip 20 is mounted in each groove 11 and the LED chip 20 is covered by the first molding part 42 and the second molding part 44. By cutting the package material 100 so that each LED chip 20 can be separated from each other, the side emitting type LED package 1 according to another embodiment of the present invention described above can be manufactured. At this time, the second molding part 44 positioned on the same plane and the lateral side surface of the PCB become cut surfaces from the package material 100.

According to the embodiment of the present invention, the grooves filled with the liquid resin on the PCB on which the LED chip is mounted can form a predetermined lens shape in the vicinity of the LED chip. In addition, it is possible to optimize the transmission of light to the side of the light guide plate of the backlighting unit by suppressing light emission in the vertical direction but widening the light emission range in the horizontal direction.

Further, according to the embodiment of the present invention, reliability can be improved by forming the first molding part with a silicone resin.

According to the embodiment of the present invention, by containing at least one phosphor in the first molding part, it is possible to give various color changes by appropriately combining the light emitted from the LED chip and the phosphor.

Claims

A PCB having a groove on an upper surface thereof;

An LED chip mounted in the groove;

A first molding part filled in the groove to cover the LED chip;

A second molding part formed on the PCB so as to cover the first molding part, the second molding part having an upper light emitting surface wide in the horizontal direction and narrow in the vertical direction;

Including,

Each of the transverse side surfaces of the second molding part perpendicular to the upper surface of the PCB forms the same plane as each of the long side surfaces of the PCB, and includes a total internal reflection surface of the PCB.

delete

The method according to claim 1,

The upper light emitting surface is a side-emitting type LED package, characterized in that formed in a convex curved surface symmetrical left and right in the horizontal direction.

The method according to claim 1,

The first molding part is formed of a silicon material,

A side emitting type LED package containing at least one phosphor.

delete

The method according to claim 1,

The vertical side light-emitting LED package, characterized in that the vertical light emitting surface is perpendicular to the upper side and adjacent to the horizontal side surface is formed in a curved surface.

Preparing a PCB having a groove formed on an upper surface thereof;

Mounting an LED chip inside the groove;

Connecting the mounted LED chip by a bonding wire,

Forming a first molding part formed in the groove to cover the LED chip;

Forming a second molding part formed on the PCB so as to cover the first molding part, the second molding part having an upper light emitting surface wide in the horizontal direction and narrow in the vertical direction,

Performing a cutting process to form individual packages,

Including,

The step of performing the cutting process

The individual packages may be formed such that each of the transverse side surfaces of the second molding part perpendicular to the upper surface of the PCB is coplanar with each of the long side surfaces of the PCB and is formed as a total internal reflection surface of the plane. Method of manufacturing a side-emitting LED package.