KR20090002281A

KR20090002281A - Light emitting diode module with enhanced heat release for lumination

Info

Publication number: KR20090002281A
Application number: KR20070062873A
Authority: KR
Inventors: 정철
Original assignee: (주)아스트로
Priority date: 2007-06-26
Filing date: 2007-06-26
Publication date: 2009-01-09
Also published as: KR100889603B1

Abstract

The present invention comprises a first layer composed of a mixture (Ag / ceramic / epoxy) of 60 to 70 wt% epoxy resin, 20 to 25 wt% silver (Ag) particles, and 10 to 15 wt% ceramic particles; A second layer comprising a metal printed circuit board (PCB) mounted with a heat radiating member; Light emitting diode (LED) device laminated on a mixture (Ag / ceramic / epoxy) of 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles A third layer in which the PCB patterns are connected by gold wires at regular intervals and filled with a transparent gel-type silicon-based material; And it provides a light emitting diode (LED) module for improved heat radiation, characterized in that it comprises a fourth layer consisting of a combination of silicon and phosphor.

The light emitting diode (LED) module for improved heat dissipation according to the present invention prevents light from being diffused due to precipitation of phosphor and deterioration of brightness, thereby maximizing light of the light emitting diode (LED) device, thereby providing high luminance light. In addition to the heat dissipation, the heat dissipation can be prevented from deteriorating the LED life and the heat sink can be miniaturized by heat dissipation primarily under the LED chip and heat dissipation under the metal PCB. .

Description

LIGHT EMITTING DIODE MODULE WITH ENHANCED HEAT RELEASE FOR LUMINATION}

1 illustrates a configuration of a light emitting diode module for improved heat radiation according to the present invention.

1: appearance injection molding 2, 7: metal PCB

3: Blend of Silicone and Phosphor 4: Transparent Gel Type Silicone Material

5: gold wire 6: PCB pattern

8: LED device 9, 10: Ag / ceramic / epoxy

The present invention relates to a light emitting diode (LED) module for lighting with improved heat dissipation. Specifically, the present invention maximizes the light of a light emitting diode (LED) device by using a transparent gel-type silicon-based material, and a combination of silicon and a phosphor to prevent a decrease in light spreadability and brightness due to precipitation of the phosphor. Using a mixture of 60 to 70 wt% epoxy resin, 20 to 25 wt% silver (Ag) particles, and 10 to 15 wt% ceramic particles (Ag / ceramic / epoxy) to primarily radiate heat under the LED chip. The present invention relates to a light emitting diode (LED) module for lighting that prevents degradation of LED lifespan by minimizing heat dissipation under a metal PCB and enables miniaturization of a heat sink.

A light emitting diode (LED) consists of a junction between a p-type and an n-type semiconductor, and is a type of optoelectronic device that emits energy corresponding to a band gap of a semiconductor in the form of light by combining electrons and holes when a voltage is applied. Light emitting diodes (LEDs) have been used as display and image light sources for electronic devices, including information and communication devices, and since the mid-1990s, blue LEDs have been developed to enable full-color displays. The light emitting diode (LED) light source is a light source with low heat loss, which consumes much less energy than incandescent bulbs, which can save energy, exhibit excellent characteristics in terms of life and maintenance, and are environmentally friendly with no mercury. Light-emitting diodes (LEDs) are widely used in general lighting, building decoration, mood lamps, vehicles, traffic signals, indoor and outdoor billboards, induction lamps, warning lights, light sources for various security equipment, and light sources for sterilization or disinfection. .

However, the conventional light emitting diode (LED) module has a problem in that the light diffusion and brightness decrease due to the precipitation of the phosphor. Therefore, there is a limit in generating high brightness light.

Korean Patent Publication No. 552636 describes 'improving the heat dissipation performance by molding the base of the LED package with a thermally conductive polymer'; Korean Patent Publication No. 671240 discloses that 'high heat generated from LED is quickly conducted to the aluminum radiator through the thermoelectric module and the heat conductor, and the conducted heat radiates the high heat concentrated from the heat conductor as well as the heat radiator itself. And through the heat sink fins to release to the outside; Korean Patent Publication No. 646198 discloses 'efficiently dissipating heat generated in a high power LED chip to the outside by forming a heat dissipating wall or heat radiation flaw on a metal slug'; Korean Patent Publication No. 670918 describes a large area leadframe made of pure Cu and fused a heat sink made of pure copper to the bottom of the leadframe by ultrasonic welding, thereby preventing from LED lamps. Effective heat dissipation of the generated heat to minimize damage to the LED device due to the heat generated even when a large amount of current is applied.

However, these prior patent documents have no reference or suggestion to simultaneously seek heat dissipation under the LED chip and heat dissipation under the metal PCB.

On the other hand, large-capacity LED modules mostly have large heat sinks or heat sinks, and when there is no thermal stability improvement effect on the heat sinks or heat sinks, the LED chip is thermally shocked, resulting in a decrease in brightness and ultimately, This will shorten the life of the LED module. Ag / epoxy has also been found to fix the LED chip and contribute to the thermal stability of the LED chip, but the heat dissipation effect is not satisfactory.

The present invention relates to a light emitting diode (LED) module for lighting with improved heat dissipation. Specifically, the present invention maximizes the light of a light emitting diode (LED) device by using a transparent gel-type silicon-based material, and a combination of silicon and a phosphor to prevent a decrease in light spreadability and brightness due to precipitation of the phosphor. Using a mixture of 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles (Ag / ceramic / epoxy) to heat primarily under the LED chip It is an object of the present invention to provide a light emitting diode (LED) module for lighting that prevents degradation of the LED lifespan by minimizing heat dissipation under the PCB and enables miniaturization of a heat sink.

In Ag / ceramic / epoxy of the first layer and the third layer, the average diameter of silver (Ag) particles is preferably 20 to 400 nm, and the average diameter of the ceramic particles is 30 to 250 nm. The ceramic particles are, for example, high thermal conductivity ceramic particles selected from the group consisting of alumina (Al ₂ O ₃ ), silicon carbide (SiC) and aluminum nitride (AlN). Ag / ceramic / epoxy of the first layer preferably has a thermal conductivity K of 3 to 5 W / (m · K).

Metal PCB (Printed Circuit Board) has better heat dissipation effect than general PCB. However, due to the trend of high density integration of the LED chip and small weight of the LED module, there may be a limit in dissipating a large amount of heat generated in the LED device, thereby minimizing the risk of damage to the LED device due to heat accompanying light emission. For this purpose, the metal PCB is preferably provided with a heat dissipation member. Therefore, in the light emitting diode (LED) module for lighting according to the present invention, the second layer is made of a metal printed circuit board (PCB) mounted with a heat dissipation member.

In the third layer constituting the light emitting diode (LED) module for heat dissipation improved according to the present invention, 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles Light emitting diode (LED) elements and PCB patterns stacked on a mixture of% (Ag / ceramic / epoxy) are connected by gold wires. Here, Ag / ceramic / epoxy serves as a conductive adhesive, Ag (silver) particles can significantly improve the electrical conductivity and heat deformation temperature, it is possible to prevent the modification of the epoxy resin. Light emitting diode (LED) elements stacked on Ag / ceramic / epoxy and individual LED chips having PCB patterns connected by gold wires are arranged at regular intervals. The remainder of the third layer is filled with a transparent gel-type silicon-based material, which is applied flat and homogeneously on the light emitting diode (LED) device. Therefore, it is possible to effectively prevent the phenomenon of deterioration of light diffusivity and brightness due to precipitation of the phosphor.

The fourth layer constituting the light emitting diode (LED) module for improved heat dissipation according to the present invention is composed of a combination of silicon and phosphor. It is preferable that the compounding ratio of silicone and fluorescent substance is 0.1: 9.9-2.0: 8.0.

The light emitting diode (LED) module for improved heat dissipation according to the present invention is, for example, in the case of indium gallium nitride (InGaN) -based blue light emitting diode (LED) in implementing a white light source, for example, YAG (yttrium aluminum garnet) A method of exciting a light emitter is used, or a method of exciting red (R) / green (G) / blue (B) phosphor in an ultraviolet light emitting diode (UV LED). In addition, it is possible to produce various kinds of emission colors in addition to the white light by the combination of various phosphors, thereby increasing the application range as illumination.

The manufacturing process of the light emitting diode (LED) module for improved heat dissipation according to the present invention is as follows: 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles The LED device is laminated on a mixture of Ag / ceramic / epoxy and then reflowed and connected to the PCB pattern by gold wire bonding. The individual LED chips thus made are arranged at regular intervals, and the transparent gel-type silicon-based material is applied flatly and homogeneously on the LED device, followed by hot air drying. The layer thus formed is the third layer. Subsequently, a mixture of silicon and phosphor is uniformly coated on the third layer, followed by hot air drying to laminate the fourth layer. Subsequently, after setting a metal PCB (second layer) on which the heat dissipation member is mounted, the third layer and the fourth layer are laminated and integrated thereon. Subsequently, a mixture (Ag / ceramic / epoxy) of 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles is applied under the metal PCB (second layer). . Thereafter, it is shipped through a varnish process, an assembly process, a performance test process, a packaging process, and the like.

Claims

A first layer composed of a mixture (Ag / ceramic / epoxy) of 60 to 70% by weight of an epoxy resin, 20 to 25% by weight of silver (Ag) particles, and 10 to 15% by weight of ceramic particles;

A second layer comprising a metal printed circuit board (PCB) mounted with a heat radiating member;

Light emitting diode (LED) device laminated on a mixture (Ag / ceramic / epoxy) of 60 to 70% by weight of epoxy resin, 20 to 25% by weight of silver (Ag) particles and 10 to 15% by weight of ceramic particles A third layer in which the PCB patterns are connected by gold wires at regular intervals and filled with a transparent gel-type silicon-based material; And

A light emitting diode (LED) module for improved heat dissipation, comprising a fourth layer comprising a combination of silicon and phosphor.

The method of claim 1,

The average diameter of the silver (Ag) particles is 20 to 400 nm, the average diameter of the ceramic particles is 30 to 250 nm, the light emitting diode (LED) module for improved heat dissipation.

The method of claim 1,

The ceramic particle is a high thermal conductivity ceramic particle selected from the group consisting of alumina (Al ₂ O ₃ ), silicon carbide (SiC) and aluminum nitride (AlN), the light emitting diode (LED) module for improved heat dissipation.

The method of claim 1,

Ag / ceramic / epoxy of the first layer has a thermal conductivity coefficient (K) of 3 to 5 W / (m · K).

The method according to any one of claims 1 to 4,

The transparent gel-type silicon-based material is uniformly applied to the light emitting diode (LED) device, the compounding ratio of the silicon and the phosphor is 0.1: 9.9 to 2.0: 8.0, the light emitting diode (LED) is a blue light emitting diode (LED) Or an ultraviolet (UV) light emitting diode (LED).