CN101150163A - Heat dissipation component directly packaged with LED chip and heat sink, manufacturing equipment and method thereof - Google Patents

Abstract

A heat dissipation component directly packaged with an LED chip and a heat sink, and a manufacturing device and method thereof, and the invention relates to the technical field of LED chip and heat sink packaging. It solves the problem of difficult heat dissipation existing in the existing LED packaging structure. The packaging structure and method are as follows: a solder layer (5) is welded between an LED chip (1) coated with a chip metal film (3) and a rectangular tubular heat sink (2) coated with a heat sink metal film (4). The manufacturing device is composed of a positioning box (6), a fixing splint (7) and a fastening assembly (8), and a set of positioning boxes (6) for placing chip grooves (6-1) of LED chips (1) are arranged on the inner bottom surface of the box body. ), a pair of fastening components (8) are respectively installed on the corresponding two side walls of the positioning box (6), and the fixed splint (7) is respectively provided with the positions of the fastening components (8) at the edges of the two wide sides. A rectangular thin plate corresponding to the horseshoe-shaped notch (7-1). The invention reduces the thermal resistance of the product, so that the heat can be dissipated as soon as possible, improves the saturation current and luminous efficiency of the product, and also improves the reliability and life of the product.

Description

Heat dissipation component directly packaged with LED chip and heat sink, manufacturing equipment and method thereof

technical field

The invention relates to the technical field of LED chip and heat sink packaging.

Background technique

The full name of LED is semiconductor light-emitting diode, which can directly convert electrical energy into light energy. It is characterized by low power consumption, high brightness, bright colors, anti-vibration, long life, cold light source and so on. LED products are widely used, especially with the substantial increase in luminous efficiency and power, various lighting products using LED as light source will inevitably replace incandescent lamps in the 21st century.

Semiconductor components are usually very sensitive to temperature. For high-power LEDs, the driving current is generally above several hundred milliamps, and the temperature rise of the P-N junction is very obvious. Many applications require multiple high-power LEDs to be used in dense arrays. Its heat dissipation problem is particularly prominent. Prolonged heating or high temperature will bring stability and service life problems. If the P-N junction temperature of the LED is 25°C (typical operating temperature), the brightness is 100, then the brightness will drop to 80 when the temperature rises to 75°C, the brightness will be 60 when the temperature reaches 125°C, and the brightness will be 175°C. Only 40 left. There is a negative linear relationship between junction temperature and luminance. The effect of temperature on brightness is linear, but the effect on life is exponential. If the LED is kept below 50°C, it will have a lifespan of nearly 20,000 hours; at 75°C, there will be 10,000 hours left; 1,000 hours left at ℃. Therefore, the problem of heat dissipation is a major technical problem hindering the rapid popularization of high-power LED lighting applications.

The traditional package structure of power LED is shown in Fig. 1. First, the chip 1a is mounted on the substrate 4a, and then the substrate 4a is glued on the package 6a. Package 6a is bonded to heat sink 2a with thermal interface material 7a. If this structure is adopted, the substrate, adhesive layer, and packaging layer become the main parts that hinder the heat dissipation of the chip. The thermal resistance from the chip to the external heat sink is usually greater than 20°C/W.

Contents of the invention

In order to solve the problem of difficult heat dissipation in the existing LED packaging structure, the present invention proposes a heat dissipation assembly in which an LED chip and a heat sink are directly packaged and its manufacturing equipment and method.

The heat dissipation assembly in which the LED chip and the heat sink are directly packaged is composed of an LED chip 1, a rectangular tubular heat sink 2, a chip metal film 3, a heat sink metal film 4 and a solder layer 5; the lower surface of the LED chip 1 is coated with a chip metal film 3. A heat sink metal film 4 is plated on the upper surface of the rectangular tubular heat sink 2 , and the solder layer 5 is placed between the chip metal film 3 and the heat sink metal film 4 .

The equipment for manufacturing heat dissipation components directly packaged with LED chips and heat sinks is composed of a positioning box 6, a fixing splint 7 and a fastening component 8. The inner bottom surface of the box body of the positioning box 6 is provided with a set of chip grooves 6-1 for placing LED chips 1. A pair of fastening assemblies 8 are respectively installed on the corresponding two side walls of the positioning box 6, and the fastening assemblies 8 are composed of fastening trunnions 8-1, fastening bolts 8-2, fastening gaskets 8-3, fastening The fastening spring 8-4 and the fastening nut 8-5 are composed; the fastening trunnion 8-1 is fixed on the side wall of the positioning box 6, and one end of the fastening bolt 8-2 is fixed on the fastening trunnion 8-1 , fastening gasket 8-3, fastening spring 8-4 and fastening nut 8-5 are arranged in sequence from one end to the other end of fastening bolt 8-2, and fastening splint 7 is two wide edge places respectively A rectangular thin plate with a horseshoe-shaped notch 7-1, the position of the horseshoe-shaped notch 7-1 corresponds to the position of the fastening component 8.

The steps of the method for manufacturing the heat dissipation component in which the LED chip and the heat sink are directly packaged are as follows:

Step 1: Plating a heat sink metal film 4 on each solder spot at a preset position on the upper surface of a rectangular tubular heat sink 2, and then plating or printing a solder layer 5 to form preset solder bumps;

Step 2: Coating solder paste on the solder bumps of the solder layer 5;

Step 3: Align and bond the LED chip 1 coated with the chip metal film 3 on the lower surface with the solder bump;

Step 4: Place the rectangular tubular heat sink 2 covered with LED chips 1 in a reflow oven for heating and brazing;

Step 5: Cover the surface of the soldered LED chip 1 with a hollow lead plate to complete the manufacture.

For the packaging and application of LED chips, the thermal resistance of the product is reduced, so that the heat generated by the P-N junction can be dissipated as soon as possible, which can not only improve the saturation current and luminous efficiency of the product, but also improve the reliability and life of the product. Avoid heat dissipation bottlenecks in the heat conduction channel in the design to ensure that heat is dissipated quickly from the inside to the outside. Based on previous research results, the present invention removes the high thermal resistance ceramic substrate and silver glue bonding layer or spacer, and directly brazes the bare chip on the heat sink, which fundamentally solves the bottleneck problem of heat dissipation. The heat sink designed in the present invention is in the shape of a rectangular tube. On the one hand, it is more convenient to combine with other components of the lamp. On the other hand, it is convenient to connect multiple sets of heat sinks together. wind cold. The invention is applicable to single-chip and multi-chip array packages.

Description of drawings

Fig. 1 is a sectional view of a traditional typical LED chip packaging structure; Fig. 2 is a structural schematic diagram of a heat dissipation assembly directly packaged with an LED chip and a heat sink of the present invention; Fig. 3 is a heat dissipation assembly directly packaged with an LED chip and a heat sink of the present invention Schematic diagram of the structure of the device; FIG. 4 is a flow chart of the method for manufacturing a heat dissipation assembly in which LED chips and heat sinks are directly packaged according to the present invention.

Detailed ways

Specific Embodiment 1: This embodiment is described in conjunction with FIG. 2. The heat dissipation assembly in which the LED chip and the heat sink are directly packaged in this embodiment consists of an LED chip 1, a rectangular tubular heat sink 2, a chip metal film 3, a heat sink metal film 4 and The solder layer 5 consists of a chip metal film 3 coated on the lower surface of the LED chip 1, a heat sink metal film 4 coated on the upper surface of the rectangular tubular heat sink 2, and the solder layer 5 is placed on the chip metal film 3 and the heat sink. Between the metal films 4 , the LED chip 1 and the rectangular tubular heat sink 2 are connected through the chip metal film 3 , the heat sink metal film 4 and the solder layer 5 .

Embodiment 2: This embodiment is described with reference to FIG. 2 . The difference between this embodiment and Embodiment 1 is that the rectangular tubular heat sink 2 is made of copper or aluminum metal. Other compositions and connection methods are the same as those in Embodiment 1.

Embodiment 3: This embodiment is described with reference to FIG. 2 . The difference between this embodiment and Embodiment 1 is that the chip metal film 3 and the heat sink metal film 4 are made of gold Au or silver Ag. Other compositions and connection methods are the same as those in Embodiment 1.

Embodiment 4: This embodiment is described in conjunction with FIG. 2. The difference between this embodiment and Embodiment 1 is that the solder layer 5 adopts tin-silver SnAg, tin-silver-copper SnAgCu or tin-lead SnPb alloy solder with small thermal resistance, and The tissue is dense and the heat conduction is smooth. Other compositions and connection methods are the same as those in Embodiment 1.

Embodiment 5: This embodiment is described with reference to FIG. 2 . The difference between this embodiment and Embodiment 1 is that the total thickness of the chip metal film 3 , the heat sink metal film 4 and the solder layer 5 is 50-150 μm. Other compositions and connection methods are the same as those in Embodiment 1.

Specific Embodiment 6: This embodiment is described in conjunction with FIG. 3. The device for manufacturing a heat dissipation assembly in which an LED chip and a heat sink are directly packaged in this embodiment is composed of a positioning box 6, a fixing splint 7, and a fastening assembly 8. The box body of the positioning box 6 The inner bottom surface is provided with a group of chip grooves 6-1 for placing LED chips 1, and a pair of fastening components 8 are respectively installed on the two side walls corresponding to the positioning box 6, and the fastening components 8 are composed of fastening trunnions 8-1, Fastening bolt 8-2, fastening gasket 8-3, fastening spring 8-4 and fastening nut 8-5 are composed; fastening trunnion 8-1 is fixed on the side wall of positioning box 6, fastening One end of the bolt 8-2 is fixed on the fastening trunnion 8-1, and one end to the other end of the fastening bolt 8-2 is provided with a fastening washer 8-3, a fastening spring 8-4 and a fastening nut in sequence 8-5, the fixed splint 7 is a rectangular thin plate with horseshoe-shaped notches 7-1 on the two wide edges, and the positions of the horseshoe-shaped notches 7-1 correspond to the positions of the fastening components 8 .

Specific Embodiment 7: This embodiment is described in conjunction with FIG. 4 . This embodiment is a method for manufacturing a heat dissipation component directly packaged with an LED chip and a heat sink. The steps are as follows:

Step 1: Plating a heat sink metal film 4 on each solder spot at a preset position on the upper surface of a rectangular tubular heat sink 2, and then plating or printing a solder layer 5 to form preset solder bumps;

Step 2: Coating solder paste on the solder bumps of the solder layer 5;

Step 3: Align and bond the LED chip 1 coated with the chip metal film 3 on the lower surface with the solder bump;

Step 4: Place the rectangular tubular heat sink 2 covered with LED chips 1 in a reflow oven for heating and brazing;

Step 5: Cover the surface of the soldered LED chip 1 with a hollow lead plate to complete the manufacture.

Embodiment 8: This embodiment is described in conjunction with FIG. 3 . The difference between this embodiment and Embodiment 6 is that in step 3, a device for manufacturing a heat dissipation assembly in which the LED chip and the heat sink are directly packaged is used for welding, and the lower surface is plated with chip metal. The film 3 is poured into the chip groove 6-1, and the processed rectangular tubular heat sink 2 is placed in the positioning box 6, so that the LED chip 1 and the solder bump are aligned and bonded, and then covered with the fixing splint 7 On the rectangular tubular heat sink 2, lift the fastening assembly 8 on both sides, lean into the horseshoe-shaped gap 7-1 of the fixed splint 7, press the fixed splint 7 with the fastening gasket 8-3, and tighten the fastening nut 8 -5. Other compositions and connection methods are the same as those in Embodiment 1.

Claims (8)

1.LED the radiating subassembly of chip and heat sink direct encapsulation, it is characterized in that it by led chip (1), rectangular tubular is heat sink (2), chip metal film (3), heat sink metal film (4) and solder layer (5) are formed; Lower surface at led chip (1) is coated with chip metal film (3), is coated with heat sink metal film (4) at the upper surface of rectangular tubular heat sink (2), and solder layer (5) places between chip metal film (3) and the heat sink metal film (4).

2. the radiating subassembly of led chip according to claim 1 and heat sink direct encapsulation is characterized in that rectangular tubular heat sink (2) adopts copper or aluminum metallic material.

3. the radiating subassembly of led chip according to claim 1 and heat sink direct encapsulation is characterized in that chip metal film (3) and heat sink metal film (4) adopt golden Au or silver-colored Ag material.

4. the radiating subassembly of led chip according to claim 1 and heat sink direct encapsulation is characterized in that solder layer (5) adopts tin silver SnAg, SAC SnAgCu or the plumbous SnPb solder alloy of tin.

5. the radiating subassembly of led chip according to claim 1 and heat sink direct encapsulation, the gross thickness that it is characterized in that chip metal film (3), heat sink metal film (4) and solder layer (5) is 50～150 μ m.

6. make the equipment of the radiating subassembly of led chip and heat sink direct encapsulation, it is characterized in that it is made up of positioning box (6), strap (7) and fastening assembly (8), the box body inner bottom surface of positioning box (6) is provided with one group of chip groove (6-1) of placing led chip (1), be separately installed with a pair of fastening assembly (8) on corresponding two sidewalls of positioning box (6), fastening assembly (8) is made up of fastening gudgeon (8-1), fastening bolt (8-2), fastening pad (8-3), fastening spring (8-4) and fastening nut (8-5); Fastening gudgeon (8-1) is fixed on the sidewall of positioning box (6), one end of fastening bolt (8-2) is fixed on the fastening gudgeon (8-1), the end to end of fastening bolt (8-2) is disposed with fastening pad (8-3), fastening spring (8-4) and fastening nut (8-5), strap (7) is the rectangle thin plate that two broadside edges have shape of a hoof breach (7-1), and shape of a hoof breach (7-1) position is corresponding with the position of fastening assembly (8).

7. make the method for the radiating subassembly of led chip and heat sink direct encapsulation, it is characterized in that the step of its method is as follows:

Step 1: first plating heat sink metal film (4) on each solder joint of upper surface predeterminated position of rectangular tubular heat sink (2), and then plating or printing go up solder layer (5), forms default solder bump;

Step 2: on the solder bump of solder layer (5), be coated with weld-aiding cream;

Step 3: the led chip (1) that respectively lower surface is coated with chip metal film (3) aligns bonding with solder bump;

Step 4: the rectangular tubular heat sink (2) that will be covered with led chip (1) places reflow soldering, heating soldering;

Step 5: the surface of the led chip (1) that welds is covered with the lead plate of hollow out, finishes manufacturing.

8. the method for the radiating subassembly of manufacturing led chip according to claim 6 and heat sink direct encapsulation, it is characterized in that step 3 adopts the device of the radiating subassembly of making led chip and heat sink direct encapsulation to weld, lower surface is coated with chip metal film (3) to be put upside down in the chip groove (6-1), the rectangular tubular of handling well heat sink (2) is put into positioning box (6), make led chip (1) and solder bump align bonding, use strap (7) to be placed on the rectangular tubular heat sink (2) again, two sides fastening assembly (8) is lifted, lean in the shape of a hoof breach (7-1) of strap (7), push down strap (7) with fastening pad (8-3), screw fastening nut (8-5).

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