KR100851367B1 - Light emitting diode - Google Patents

Abstract

The present invention relates to a light emitting diode, and more particularly, to a light emitting diode using a substrate having excellent heat dissipation performance. The present invention forms a via hole filled with a thermally conductive material and penetrates through the substrate of the light emitting diode, thereby effectively dissipating heat emitted from the light emitting diode chip to the outside. Furthermore, by forming the inlet portion into which the heat of the via hole enters in a relatively large area, heat transfer can be facilitated to maximize the heat dissipation effect, thereby extending the life of the light emitting diode chip.

Light Emitting Diode, LED, Light Emitting Element, Heat Dissipation Efficiency, Through, Via Hole

Description

Light emitting diodes

1 is a cross-sectional view showing a conventional light emitting diode.

2 is a sectional view showing a first embodiment according to the present invention;

3 is a sectional view showing another example of the first embodiment according to the present invention;

4 is a sectional view showing another example of the first embodiment according to the present invention;

5 is a sectional view showing a second embodiment according to the present invention;

6 is a sectional view showing a third embodiment according to the present invention;

7 is a sectional view showing a fourth embodiment according to the present invention;

8 is a sectional view showing a fifth embodiment according to the present invention;

<Explanation of symbols for the main parts of the drawings>

110, 210, 310, 410, 510: substrate

140, 240, 340, 440, 540: light emitting diode chip

150, 250, 350, 450, 550: Wiring

160, 260, 360, 460, 560: molding part

170, 180, 190, 270, 370, 470, 570: Via Hole

The present invention relates to a light emitting diode, and more particularly, to a light emitting diode using a substrate having excellent heat dissipation performance.

A light emitting diode (LED) refers to a device in which electrons and holes meet and emit light at a P-N semiconductor junction by application of a current. The light emitting device using the light emitting diode as described above has a small power consumption and a lifetime of several to several tens of times compared to a conventional light bulb or a fluorescent lamp, and is superior in terms of reducing power consumption and durability.

1 is a cross-sectional view showing a conventional light emitting diode.

Referring to FIG. 1, a light emitting diode includes a substrate 10, first and second lead patterns 20 and 30 formed on the substrate 10, and light emission mounted on the first lead pattern 20. A molding for encapsulating the diode chip 40, the wiring 50 electrically connecting the light emitting diode chip 40 and the second lead pattern 30, and the light emitting diode chip 40 and the wiring 50. The unit 60 is included.

The brightness of the above-described light emitting diode is proportional to the current applied to the light emitting diode chip 40, and the current applied to the light emitting diode chip 40 is proportional to the heat emitted by the light emitting diode chip 40. In order to brighten the brightness of the light emitting diode, a high current must be applied, but the light emitting diode chip 40 is damaged by the heat emitted from the light emitting diode chip 40, thereby causing a problem in that a high current cannot be applied indefinitely.

In the conventional light emitting diode having the above configuration, heat generated from the light emitting diode chip 40 is discharged through the substrate 10 or the lead patterns 20 and 30. However, there is a limit in heat dissipation which is only generated by the substrate 10 or the lead patterns 20 and 30 of the light emitting diode, thereby reducing the lifetime of the device.

Thus, many studies have been conducted to effectively emit heat emitted by the LED chip. For example, a light emitting diode having a heat emission path formed by filling an inside of a through hole through a substrate on which a light emitting diode chip is mounted with a heat conductive material has been proposed. However, a light emitting diode having such a structure has a problem in that a high heat resistance is generated at an inlet portion of a through hole through which heat is transferred, so that an efficient heat dissipation effect cannot be expected.

The present invention is to solve the above problems, by forming a via hole including a heat inlet of a relatively large area on the substrate on which the light emitting diode chip is mounted, thereby effectively dissipating heat emitted from the light emitting diode chip and An object of the present invention is to provide a light emitting diode capable of extending the life and improving the function of the light emitting diode.

In order to achieve the above object, the present invention includes a via hole that penetrates the body and is filled with a thermally conductive material therein, wherein the via hole is formed from one surface on which the light emitting diode chip is mounted. There is provided a light emitting diode characterized in that the cross sectional area decreases toward the inside of the substrate.

The via hole includes the heat inlet portion having a cross sectional area decreasing from one surface of the body on which the light emitting diode chip is mounted to the center of the via hole, and a heat outlet portion having a cross sectional area increasing from the center of the via hole to the other surface of the body. It is characterized by.

The longitudinal cross-sectional shape of the via hole may include a curve or may include a straight line.

The thermally conductive material may include a metal, a thermally conductive resin, or a mixture of metal and paste in powder form.

Hereinafter, with reference to the accompanying drawings will be described in more detail with respect to the present invention. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

2 is a cross-sectional view showing a first embodiment according to the present invention.

Referring to FIG. 2, the light emitting diode may include a body, that is, a substrate 110, first and second lead patterns 120 and 130 formed on the substrate 110, and a first lead pattern 120. The mounted light emitting diode chip 140, the wiring 150 electrically connecting the light emitting diode chip 140 and the second lead pattern 130, and the light emitting diode chip 140 and the wiring 150. It includes a molding unit 160 for sealing. A via hole 170 filled with a thermal conductive material is formed in the substrate 110, and the via hole 170 is formed from one surface of the substrate 110 on which the photodiode chip 140 is mounted. It characterized in that it comprises a column inlet (170a) that the cross-sectional area is reduced toward the inside.

The substrate 110 may include a printed circuit board (PCB), for example, a metal core printed circuit board, in which a light emitting diode chip 140 may be mounted and an external power source may be applied. MCPCB), FR4, BT resin (Bismaleimide Triazine Resin; BT Resin) may be made of a material such as.

In order to effectively dissipate heat emitted from the LED chip 140, the via hole 170 according to the present invention is preferably formed directly below a predetermined region in which the LED chip 140 is mounted. The hole 170 may include a shape of a cylinder, an elliptic cylinder, or a polygonal cylinder. In the present embodiment, the cross-sectional area of the column inlet 170a which decreases in cross-sectional area from one surface of the substrate 110 on which the light emitting diode chip 140 is mounted to the lower side of the upper end, and the cross-sectional area from the lower side of the upper end to the lower side of the lower end. This constant heat outlet 170b is included. That is, the via hole 170 of the present embodiment is formed in the shape of a truncated cone, the diameter of which decreases toward the lower side of the upper end, and extends therefrom and has a constant cylindrical diameter at the lower end. Due to the via hole 170 having such a shape, heat emitted from the LED chip 140 mounted on the substrate 110 is transferred to the via hole 170 through the column inlet 170a formed with a relatively large area. That is, they enter the heat release path. Accordingly, it is possible to reduce the heat resistance generated at the inlet of the heat entering, to facilitate heat transfer and improve the heat dissipation effect.

The shape of the via hole is not limited thereto, and may be variously formed. For example, as shown in FIG. 3, the via hole 180 penetrating through the substrate 110 has a cross sectional area that decreases from one surface of the substrate 110 on which the LED chip 140 is mounted to the lower side of the upper end. The heat inlet 180a and the heat outlet 180b may have a cross sectional area that increases from a lower side of the upper end to a lower side of the lower end. In FIG. 3, the heat inlet 180a and the heat outlet 180b are formed to decrease and increase at a rate at which the diameter of the via hole 180 continuously changes. That is, as can be seen in the figure, the longitudinal cross-sectional shape of the via hole 180 has a predetermined curvature and includes a curve that is symmetric with each other. Accordingly, in addition to reducing heat resistance to heat entering through the heat inlet portion 180a formed in a relatively large area in comparison with the related art, the heat outlet portion 180b formed in the relatively large area of the transferred heat is reduced. By releasing to the outside through the heat dissipation can be easier to further improve the heat dissipation effect. However, not limited thereto, a via hole may be formed including a heat inlet and a heat outlet having a diameter decreasing and increasing at a constant rate. That is, the longitudinal cross-sectional shape of the via hole may include straight lines that are symmetrical with each other and decrease and increase with a predetermined constant slope.

In addition, as illustrated in FIG. 4, the via hole 190 formed to penetrate the substrate 110 has a row in which a cross-sectional area decreases from one surface of the substrate 110 on which the LED chip 140 is mounted to the lower side of the upper end. An inlet portion 190a, a heat transfer portion 190b having a constant cross sectional area from the lower side to the lower side of the upper end, and a heat outlet portion 190c of which the cross sectional area increases from the lower side to the lower side of the middle portion; can do. That is, it is formed in the shape of a truncated cone, the diameter of which decreases toward the lower side of the upper end, and extends therefrom, and extends therefrom, and a truncated cone of which the diameter increases toward the lower side of the lower end. . In FIG. 4, a heat inlet 190a and a heat outlet 190c are formed in which the diameter decreases and increases at a constant rate. That is, as can be seen in the figure, the longitudinal cross-sectional shape of the via hole is reduced and increased at a constant slope to include a column inlet 190a and a column outlet 190c formed of straight lines symmetric with each other.

As described above, in the via holes 170, 180 and 190 vertically penetrating the substrate 110, the via holes 170, 180 and 190 include column inlets 170a, 180a and 190a having a relatively large area. ) May be formed in various ways. The shape of the via hole is not limited to the above description, and combinations or modifications thereof can be made.

As a thermally conductive material filled in the via holes 170, 180, and 190, a metal or a resin having excellent thermal conductivity may be used, and materials such as copper (Cu), aluminum (Al), and silver (Ag) may be used. It is also possible to use a mixture of powdered metals and pastes.

The lead patterns 120 and 130 are formed of first and second lead patterns 120 and 130 for connecting to an external power source on the substrate 110. The substrate 110 may be formed by a printing technique or by using an adhesive. Can be formed on. The lead patterns 120 and 130 may use a metal material including copper or aluminum having excellent conductivity.

The light emitting diode chip 140 may be mounted on the substrate 110 using various mounting members and methods. For example, the light emitting diode chip 140 may be mounted on the first lead pattern 120 coated with silver paste as shown in the figure, and the light emitting diode chip 140 emits light on a predetermined region of the substrate 110 using a non-conductive adhesive. The diode chip 140 may be mounted.

In the present exemplary embodiment, the LED chip 140 is mounted on the first lead pattern 120 and electrically connected to the second lead pattern 130 through one wire 150. That is, the negative electrode is directly mounted on the first lead pattern 120 using a vertical light emitting diode chip having positive and negative electrodes on the upper and lower planes of the LED chip, respectively, and the wiring 150 is mounted. The positive electrode and the second lead pattern 130 may be connected to each other. However, the present invention is not limited thereto, and in the case of using a horizontal LED chip having a positive electrode and a negative electrode on an upper plane of the LED chip, two wires may be used to connect the lead patterns 120 and 130.

The shape and number of the lead patterns 120 and 130, or the mounting of the LED chip 140 according thereto are not limited to the above descriptions, and may be variously configured. For example, a plurality of light emitting diode chips 140 may be included as desired, which may be mounted on the plurality of lead patterns 120 and 130 to be driven separately.

A molding unit 160 is formed on the substrate 110 to encapsulate the LED chip 140 and to fix the wiring 150 connected to the LED chip 140. The molding part 160 may be formed by curing or semi-curing a transparent epoxy or silicone resin using a predetermined mold. Although the molding part 160 is formed in a square shape in the drawing, the shape of the molding part 160 is not limited thereto, and may be formed in various shapes to serve as a lens for collecting light emitted from the LED chip 140.

In addition, a phosphor (not shown) may be further included around the light emitting diode chip 140 to absorb at least a portion of the light emitted from the light emitting diode chip 140 and convert the wavelength into light having a longer wavelength than that of the light absorbed. have. The phosphor may be disposed to cover the periphery of the light emitting diode chip 140 or may be uniformly distributed in the molding part 160 encapsulating the light emitting diode chip 140.

Table 1 shows a simulation result comparing the heat emission effect of the light emitting diode according to the prior art and the present embodiment. Here, Comparative Example 1 is a case where the via hole of a constant diameter of 0.5mm is formed vertically penetrating the substrate, Experimental Example 1 has the same shape as shown in Figure 3, the diameter of the top and bottom is 0.7mm and the longitudinal section In the case where the via hole including a symmetrical curve having a curvature of 0.3 pi is formed, Experimental Example 2 has the same shape as shown in FIG. 4, wherein the upper and lower diameters are 0.7 mm and the central diameter is 0.5 mm. And a via hole including a symmetrical straight line with a 45 degree slope in longitudinal section shape. After operating the light emitting diode in each case, the maximum temperature of the light emitting diode was measured.

LED maximum temperature (℃) Comparative Example 1 43.6 Experimental Example 1 42.6 Experimental Example 2 41.9

Referring to Table 1, in Experimental Example 1 and Experimental Example 2 than the Comparative Example 1, the maximum temperature of the light emitting diode is relatively lower. That is, in Experimental Example 1 and Experimental Example 2, the heat emitted from the light emitting diode chip can be more effectively discharged to the outside. Therefore, according to the present embodiment, it can be seen that by forming the inlet portion into which the heat of the via hole enters in a relatively large area, the heat dissipation effect can be improved by reducing the thermal resistance as compared with the conventional art.

As described above, the light emitting diode of the present embodiment can effectively discharge heat emitted from the light emitting diode chip to the outside through a via hole filled with a thermally conductive material having high thermal conductivity. Furthermore, by forming the inlet portion into which the heat of the via hole enters a relatively large area, it is possible to reduce heat resistance to facilitate heat transfer and to improve heat dissipation effect.

Next, a light emitting diode according to a second exemplary embodiment of the present invention will be described with reference to the accompanying drawings. The light emitting diode according to the second embodiment of the present invention to be described below is substantially the same as the technical configuration described with reference to FIG. 4 among the above-described first embodiments, but a plurality of via holes are formed in the substrate. In the detailed description thereof, the overlapping description thereof will be omitted.

5 is a sectional view showing a second embodiment according to the present invention.

Referring to FIG. 5, a light emitting diode is formed on a body, that is, on a substrate 210, first and second lead patterns 220 and 230 formed on the substrate 210, and on the first lead pattern 220. The mounted light emitting diode chip 240, the wiring 250 electrically connecting the light emitting diode chip 240 and the second lead pattern 230, and the light emitting diode chip 240 and the wiring 250. It includes a molding part 260 for sealing. The substrate 210 has a plurality of via holes 270 filled with thermally conductive materials therein, and the via holes 270 are formed from one surface of the substrate 21 on which the light emitting diode chip 240 is mounted. It characterized in that it comprises a column inlet 270a, the cross-sectional area is reduced toward the inside.

As mentioned above, in the present embodiment, a plurality of via holes 270 are formed through the substrate 210, and a plurality of via holes 270 may be formed in various ways. That is, when a plurality of via holes are arranged as shown in the drawing, in order to effectively dissipate heat emitted from the light emitting diode chip, the plurality of via holes are disposed under the first lead pattern on which the light emitting diode chip is mounted. It is preferable.

The light emitting diode of this embodiment reduces heat resistance due to the via holes, thereby effectively dissipating heat emitted from the light emitting diode chip, and at the same time, a plurality of via holes are formed to increase the heat dissipation path, thereby improving heat dissipation more effectively. have.

Next, a light emitting diode according to a third exemplary embodiment of the present invention will be described with reference to the accompanying drawings. The light emitting diode according to the third embodiment of the present invention to be described later has almost the same technical configuration as the above-described first and second embodiments, but the via hole is connected to the first lead pattern and the second lead pattern to have a larger area. It is characterized by being formed. In the detailed description thereof, the overlapping description thereof will be omitted.

6 is a sectional view showing a third embodiment according to the present invention.

Referring to FIG. 6, a light emitting diode is formed on a body, that is, on a substrate 310, first and second lead patterns 320 and 330 formed on the substrate 310, and on the first lead pattern 320. The mounted light emitting diode chip 340, the wiring 350 for electrically connecting the light emitting diode chip 340 and the second lead pattern 330, and the light emitting diode chip 340 and the wiring 350. It includes a molding part 360 to seal. The substrate 310 has a via hole 370 filled with a thermally conductive material therein and is connected to the first lead pattern 320 and the second lead pattern 330, and the via hole 370 is formed in the substrate 310. The light emitting diode chip 340 includes a column inlet 370a having a cross sectional area decreasing from one surface of the substrate 310 on which the light emitting diode chip 340 is mounted.

The via hole 370 of the present exemplary embodiment may penetrate the substrate 310 to connect the first lead pattern 320 and the second lead pattern 330 to form a heat dissipation path in a larger area. Here, the thermally conductive material filled in the via hole 370 of the present embodiment for the electrical disconnection of the first lead pattern 320 and the second lead pattern 330 may be an insulating material, for example, a polymer matrix such as resin or rubber. A thermally conductive resin in which a thermal conductivity reinforcing agent having a high thermal conductivity is mixed with the material may be used, or an insulating layer may be formed on the via hole.

The light emitting diode of this embodiment reduces heat resistance due to the via hole, thereby effectively dissipating heat emitted from the light emitting diode chip, and at the same time, increasing the cross-sectional area of the heat dissipation path due to the increased area of the via hole, thereby improving heat emission more effectively. can do.

The present invention is not limited to the light emitting diode having the above-described structure, but can be applied to a product having various structures including a light emitting diode chip and a substrate mounting the same. Duplicate description will be omitted for the various embodiments described below. These embodiments according to the invention may be practiced independently or in combination with one another.

Next, a light emitting diode according to a fourth exemplary embodiment of the present invention will be described with reference to the accompanying drawings. In the detailed description thereof, the overlapping description thereof will be omitted.

7 is a sectional view showing a fourth embodiment according to the present invention.

Referring to FIG. 7, the light emitting diode includes a body on which the reflective part 480 is formed, that is, the substrate 410, the first and second lead patterns 420 and 430 formed on the substrate 410, and the first. A light emitting diode chip 440 mounted on the lead pattern 420, a wiring 450 electrically connecting the light emitting diode chip 440 to the second lead pattern 430, and the light emitting diode chip 440. ) And a molding part 460 encapsulating the wiring 450. The substrate 410 has a via hole 470 filled with a thermally conductive material therein, and the via hole 470 is formed from one surface of the substrate 410 on which the light emitting diode chip 440 is mounted. It characterized in that it comprises a column inlet (470a) is gradually reduced in cross-sectional area.

The reflector 480 is a region formed by forming a predetermined groove in the center region of the substrate 410 through mechanical processing, and giving a predetermined slope to the sidewall surface of the groove. The lower surface of the light emitting diode chip 440 is preferably flat to facilitate mounting, and the inner surface of the reflecting portion may have a predetermined slope to maximize reflection of light emitted from the light emitting diode chip 440 and increase luminous efficiency. Can be.

A via hole 470 penetrating the substrate 410 is formed directly under a predetermined region where the LED chip 440 is mounted. Due to the via hole 470 having a heat inlet 470a having a relatively large area, heat resistance may be reduced to effectively dissipate heat emitted from the LED chip to the outside.

Next, a light emitting diode according to a fifth embodiment of the present invention will be described with reference to the accompanying drawings. In the detailed description thereof, the overlapping description thereof will be omitted.

8 is a sectional view showing a fifth embodiment according to the present invention.

Referring to FIG. 8, the light emitting diode may include a body, that is, a substrate 510, first and second lead patterns 520 and 530 formed on the substrate 510, and a first lead pattern 520. A mounted light emitting diode chip 540, a wiring 550 for electrically connecting the light emitting diode chip 540 and the second lead pattern 530, and a light emitting diode chip formed on the substrate 510. A reflector 580 includes a hollow portion to surround the 540, and a molding unit 560 encapsulating the LED chip 540 and the wiring 550 in the hollow portion of the reflector 580. The substrate 510 has a via hole 570 filled with a thermally conductive material therein, and the via hole 570 is formed from one surface of the substrate 510 on which the light emitting diode chip 540 is mounted. It characterized in that it comprises a column inlet (570a) is gradually reduced in cross-sectional area.

A via hole 570 penetrating the substrate 510 is formed directly under a predetermined region where the LED chip 540 is mounted. Due to the via hole 570 in which the heat inlet 570a into which heat enters is formed in a relatively large area, heat resistance may be reduced to effectively dissipate heat emitted from the LED chip 540 to the outside.

As mentioned above, although this invention was demonstrated in detail using the preferable Example, the scope of the present invention is not limited to a specific Example and should be interpreted by the attached Claim. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

For example, the embodiment of the present invention has been described by specifying the body as a substrate, but is not limited to this, all kinds of bodies that can form a via hole according to the present invention and fabricate a light emitting diode instead of the substrate, for example For example, a housing, a ceramic substrate, etc. can also be used.

According to the present invention, a via hole filled with a thermally conductive material is formed vertically through a substrate of a light emitting diode, thereby effectively dissipating heat emitted from the light emitting diode chip to the outside. Furthermore, by forming the inlet portion into which the heat of the via hole enters a relatively large area, it is possible to maximize the heat dissipation effect by facilitating heat transfer, thereby extending the life of the light emitting diode chip.

Claims (5)

Body in which the light emitting diode chip is mounted, A via hole penetrating through the body and filled with a thermal conductive resin therein; The via hole includes a truncated cone shape that decreases in cross-sectional area from the one surface on which the light emitting diode chip is mounted to the inside of the body but decreases in diameter toward the lower side of the upper end, and a cylindrical shape extending from the truncated cone shape. The longitudinal shape of the light emitting diode, characterized in that it comprises a straight line. The method according to claim 1, The via hole includes the heat inlet portion having a cross sectional area decreasing from one surface of the body on which the light emitting diode chip is mounted to the center of the via hole, and a heat outlet portion having a cross sectional area increasing from the center of the via hole to the other surface of the body. Light emitting diodes, characterized in that. Body in which the light emitting diode chip is mounted, A via hole penetrating the body; The via hole is a light emitting diode, characterized in that the cross-sectional area is reduced toward the inside of the body from the surface on which the light emitting diode chip is mounted. The method according to claim 3, The via hole includes the heat inlet portion having a cross sectional area decreasing from one surface of the body on which the light emitting diode chip is mounted to the center of the via hole, and a heat outlet portion having a cross sectional area increasing from the center of the via hole to the other surface of the body. Light emitting diodes, characterized in that. delete

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