CN102969438A

CN102969438A - Sapphire bracket for LED (Light-Emitting Diode)

Info

Publication number: CN102969438A
Application number: CN2012105602338A
Authority: CN
Inventors: 左洪波; 朱晓飚; 唐寅轩
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-12-21
Filing date: 2012-12-21
Publication date: 2013-03-13

Abstract

The invention provides a sapphire bracket for an LED (Light-Emitting Diode), which comprises a sapphire single crystal and a metal wire, wherein the sapphire single crystal is a sapphire strip-shaped wafer subjected to surface machining; the metal wire connected with an LED chip is processed on the surface of the sapphire single crystal; and the surface of one side, which is in direct contact with the LED chip, of the sapphire strip-shaped wafer is coated with a metal film by adopting a film coating mode. The sapphire bracket provided by the invention is a light-transmitting heat-conducting bracket for multi-chip packaging and replaces an insulating layer and a heat sink which are used for the traditional LED chip packaging with the sapphire strip-shaped wafer subjected to surface machining; compared with the traditional MCPCB (Metal Core Printed Circuit Board) and ceramic radiating bracket, the sapphire bracket provided by the invention has good bracket light transmission by adopting a sapphire as a chip bracket in an LED structure, and can greatly increase the light-transmitting efficiency because an active layer can almost emit light rays towards all directions without loss; and compared with the traditional gold wire welding process, the sapphire bracket provided by the invention enhances the reliability and increases the efficiency by connecting LED tube cores through preset wires positioned on the sapphire bracket.

Description

LED sapphire support

(1) technical field

The present invention relates to a kind of multi-chip package with printing opacity heat conduction support, be specifically related to semiconductor lighting sapphire printing opacity cooling stand.

(2) background technology

LED be called as the 4th generation lighting source or green light source, it is a kind of cold light source, have energy-saving and environmental protection, long service life, the series of advantages such as pollution-free, can extensively be used in the aspects such as various indications, demonstration, backlight, especially have a high potential in the general lighting market development.

For low-power LED multichip packaging structure, because caloric value is little, adopts the PCB substrate to do support and get final product.And high-capacity LED for satisfying its heat radiation requirement, often adopts the MCPCB substrate, ceramic substrate or DCB substrate.Yet although above different materials can satisfy the heat radiation requirement, because material self light transmission is poor, the light that active layer sends can only send from the support top, causes the LED light extraction efficiency lower.Be to increase amount of light, increase reflector that must be on substrate.In addition, in traditional led chip encapsulating structure, for obtaining good current expansion, need to form the metal electrode layer that layer of Ni-Au forms on surface, P district by evaporation coating technique.The existence of metal level can affect and make newly energy variation of printing opacity, and the existence of lead solder-joint also makes the light extraction efficiency of device be affected.And, usually connecting between multi-chip structure chips electrode and adopt gold thread to connect, solder joint is in the follow-up operation that is coated with fluorescent material, or vibrations might cause solder joint to come off in the use procedure, make product failure.

(3) summary of the invention

The object of the present invention is to provide a kind of employing appropriate process method to obtain conductive film layer at the support single face, further produce again the chip chamber connecting circuit, and can significantly improve the LED sapphire support of light extraction efficiency.

The object of the present invention is achieved like this: it is to be made by sapphire single-crystal and metallic circuit, sapphire single-crystal is the sapphire bar shaped wafer through Surface Machining, processing is connected with the metallic circuit of led chip on the surface, sapphire bar shaped wafer length is 10-100mm, width is 0.1-10mm, thickness is 0.2-2mm, surface roughness is Ra0.1-400nm, sapphire bar shaped wafer adopts the plated film mode to plate metal film with the side surface that led chip directly contacts, the metallic circuit width of chip chamber is 1-500 μ m, and line thicknesses is 1-150 μ m.

1, the heat radiation sectional area of described sapphire wafer should be not less than 2 times of the long-pending summation of chip and support direct contact surface.

2, the metallic circuit between described led chip is made with yellow light lithography or screen printing technique, increases the thickness of circuit with plating or electroless deposition mode again.

3, described plated film mode can adopt vacuum sputtering mode or vacuum evaporation mode.

4, described metal film can adopt the conductivity such as aluminium, copper and thermal conductivity all reasonable metal and alloy.

The present invention adopts the sapphire surface processed wafer to do cooling stand, sapphire bar shaped wafer length 10-100mm, width 0.1-10mm, thickness 0.2-2mm.After process through processing on the surface, surface roughness is Ra0.1-400nm, adopt the metal or alloy films such as corresponding manner plated aluminum, copper with the side sapphire surface that chip directly contacts, then adopt relevant art to make circuit at sapphire surface, the last thickness that increases again circuit with plating or electroless deposition mode, line width 1-500 μ m, line thicknesses 1-150 μ m.With conducting resinl chip electrode and metallic circuit are coupled together at last.Metal film can adopt metal and the alloy of aluminium, copper etc.

The present invention is a kind of multi-chip package printing opacity heat conduction support, replace the insulating barrier of traditional led chip encapsulation usefulness and heat sink with the Surface Machining sapphire wafer, in the LED structure, adopt sapphire to do chip set, compare with traditional MCPCB and ceramic heat-dissipating support, the support light transmission is good, and active layer can almost can't harm the lost territory and emit beam to all directions, can greatly improve light extraction efficiency.By the prefabricated circuit on the sapphire support LED tube core is connected, compare with traditional gold thread welding procedure, improve its reliability and efficient.

Beneficial effect of the present invention has: the light extraction efficiency of LED encapsulating products is significantly increased, and cost of manufacture increases hardly; 2) sapphire substrate insulation does not need dielectric layer, and the backing material thermal conductivity is identical with adopting outward, and the support light transmission is good, and the rising angle of LED module is increased considerably, near 360 degree; 3) adopt the inverted structure good heat dissipation effect; 4) adopt the mode of the direct metal-coated membrane of sapphire surface to replace traditional gold thread connected mode, reduced on the one hand manufacturing cost, avoid on the other hand the problem that gold thread comes off easily when meeting with than big bang, improved the yields of manufacture course of products and the reliability of product.

(4) description of drawings

Fig. 1 is sapphire support schematic diagram of the present invention.

(5) embodiment

The present invention is described in detail below in conjunction with the drawings and specific embodiments.

In conjunction with Fig. 1, present embodiment adopts the sapphire processed wafer to do cooling stand, comprises sapphire bar shaped wafer 1, led chip 2 and metallic circuit 3, sapphire bar shaped wafer 1 length 30mm, width 0.8mm, thickness 0.8mm, after processed through processing on the surface, surface roughness was Ra10nm; Sapphire bar shaped wafer 1 one side surfaces adopt magnetron sputtering mode sputtering aluminum metal film, then with yellow photolithographic techniques that photoresistance coating sapphire wafer is surperficial, finishing circuit through exposure, development, etching, striping technique makes, the last thickness that increases again circuit in the electroplating deposition mode, finally make metallic circuit 3 width 80 μ m, line thicknesses 60 μ m, present embodiment metallic circuit 3 adopts the aluminum metal circuit.Couple together with electrode and the metallic circuit 3 of conducting resinl with led chip 2 at last.The aluminium fusing point is lower, and is cheap, and has good plasticity.Sapphire is the high purity aluminium oxide monocrystalline substantially, and deposited the connecing of metallic aluminium and aluminium oxide is that physics is moistening, do not have chemical reaction at interface.And the good plasticity that fine aluminium has can effectively alleviate the thermal stress that interface causes because of the thermal coefficient of expansion difference, and in addition, the peel strength between metallic aluminium and the sapphire is also larger.

Claims

1. LED sapphire support, it is characterized in that it is to be made by sapphire single-crystal and metallic circuit, sapphire single-crystal is the sapphire bar shaped wafer through Surface Machining, processing is connected with the metallic circuit of led chip on the surface, sapphire bar shaped wafer length is 10-100mm, width is 0.1-10mm, thickness is 0.2-2mm, surface roughness is Ra0.1-400nm, sapphire bar shaped wafer adopts the plated film mode to plate metal film with the side surface that led chip directly contacts, the metallic circuit width of chip chamber is 1-500 μ m, and line thicknesses is 1-150 μ m.

2. LED according to claim 1 sapphire support is characterized in that described heat radiation sectional area in sapphire wafer should be not less than chip and the long-pending summation of support direct contact surface 2 times.

3. LED according to claim 2 sapphire support is characterized in that the metallic circuit between described led chip is made with yellow light lithography or screen printing technique, increases the thickness of circuit with plating or electroless deposition mode again.

4. LED according to claim 3 sapphire support is characterized in that described plated film mode is vacuum sputtering mode or vacuum evaporation mode.