The LED packaging method is to connect the chip (Die) with its heat dissipation substrate Submount (submount technology) by wire bonding, eutectic or flip chip packaging technology to form an LED chip, and then fix the chip on the system board and connect it to form a light source module. Group.

At present, LED packaging methods can be roughly divided into lens-type and reflector-type. The molding of the lens can be molding or lens bonding; while the reflector-type chip is more It consists of glue mixing, dispensing, and packaging; in recent years, epitaxy, die-bonding, and packaging design have gradually matured, and the chip size and structure of LEDs have been miniaturized year by year. The power of a high-power single chip can reach 1~3W, or even more than 3W. As the power of LEDs continues to increase, the heat dissipation and heat resistance requirements for LED chip boards and system circuit boards are becoming increasingly stringent.

In view of the comprehensive considerations of insulation, voltage resistance, heat dissipation and heat resistance, ceramic substrates have become one of the important materials for chip sub-attachment technology. Its technology can be divided into thick film process (Thick film), low temperature co-fired process (LTCC) and thin film process (DPC). However, the thick film process and low-temperature co-firing process use screen printing technology and high-temperature process for sintering, which are prone to rough lines, inaccurate alignment, and shrinkage ratio problems. For high-power LED products with increasingly fine lines, or Especially for LED products produced by eutectic or flip-chip processes that require accurate alignment, thick-film and low-temperature co-fired ceramic substrates have gradually become insufficient.

For this reason, the high heat dissipation coefficient thin-film ceramic heat dissipation substrate is made by sputtering, electro/chemical deposition, and yellow light lithography. It has the characteristics of precise metal lines and stable material system, and is suitable for high-power, small-sized, high-brightness LEDs. The development trend of the development trend is to solve the strict requirements of the eutectic/flip-chip packaging process on the resolution and accuracy of the metal circuit on the ceramic substrate.

When the LED chip uses ceramics as the carrier board, the heat dissipation bottleneck of the LED module is transferred to the system circuit board, which transmits heat energy from the LED chip to the heat dissipation fins and the atmosphere. With the gradual improvement of the LED chip function, the material also Gradually changed from FR4 to metal core printed circuit board (MCPCB), but with the progress of high-power LED demand, the heat dissipation coefficient (2~4W/mk) of MCPCB material cannot be used for higher power products. For this reason, ceramic circuits The demand for ceramic circuit boards has gradually become popular. In order to ensure the material stability and light attenuation stability of LED products under high-power operation, the trend of ceramic machining or using ceramics as heat dissipation and metal wiring substrates has become increasingly clear. The cost of ceramic materials is currently higher than that of MCPCB. Therefore, how to use the high heat dissipation coefficient of ceramics to save material usage area and reduce production costs has become one of the important indicators for the development of ceramic LEDs.

Therefore, in recent years, the integration of polycrystalline packaging and system circuits with ceramic material COB design has gradually attracted the attention of various packaging and system manufacturers. COB is not a new technology in the electronics manufacturing industry. It refers to directly pasting the bare epitaxial wafer on the circuit board, and directly soldering the wire/welding wire to the gold-plated circuit of the PCB, which is also commonly known as the bonding wire. (Wire bonding), and through the sealing technology, the packaging steps in the IC manufacturing process are effectively transferred to the circuit board for direct assembly.

In the LED industry, since modern technology products are more and more concerned about lightness and high portability, in addition, in order to save the space problem of the system board designed with multiple LED chips, in the demand of high-power LED systems, a direct chip-attached LED has been developed. COB technology attached to the system board.

The advantages of COB are: high cost-effectiveness, simple circuit design, saving system board space, etc., but there are also technical thresholds for chip integration brightness, color temperature adjustment, and system integration. Taking the 25W LED as an example, the traditional high-power 25W LED light source must be packaged into 25 LED components with 25 1W LED chips, and the COB package is to package 25 1W LED chips in a single chip, so the required The secondary optical lens will be reduced from 25 pieces to 1 piece, which will help reduce the area of the light source, reduce materials, and system costs, thereby simplifying the secondary optical design of the light source system and saving labor costs for assembly. In addition, the high-power COB package only needs a single high-power LED to replace multiple LED packages of 1 watt or more, making the product thinner, lighter and smaller.

At present, the production of COB products on the market still mainly uses MCPCB substrates. However, MCPCB still has many problems of heat dissipation and excessive light source area to be solved. Therefore, the fundamental way is to update heat dissipation materials to the most effective led light solution. Ceramic COB substrates have the following advantages:

• Thin film technology makes the basic circuit more accurate,
• Large quantity reduces cost,
• High plasticity, can be designed according to different needs.

Currently, the LED bulbs made of MCPCB substrate COB chips cannot be dimmed, and the LED dimmable bulbs assembled with ceramic COB chips by ledaladdin company are on the market. There are 5W, 6W, 7W, better performance, and the color temperature can reach 2200K— 8000K, lumens up to 60LM/W or more.

The development of ceramic MCOB/COB is a trend to simplify the system board. The practicality, brightness, heat dissipation and cost control of lighting fixtures are all important key factors. l

Link：Ceramic COB LED Packaging Technology

The cut edge of a finished product of the normal sealing cube is usually rough and deformed with obvious cracks, and of the thicker parts, this condition becomes more apparent. This is because when the normal seal dies operation, they push the fists to bend and cut the material, and then remove the final cut part or waste material from the sheet. If there is a need for precise assembly at the cut edge, a secondary editing job will then be unavoidable to fix the cut edge. Otherwise, if there is no need for precise assembly or cosmetic purpose on the cut edge, regular sealing cubes will be a utility choice for mass production.

How to reduce production costs? Instead of using poor quality materials, look for advanced production techniques!

For example, the image below is a counterweight to a measuring device. Since the counterweight part is not for cosmetic purposes and its cut edge is not for assembly, it is advisable to use regular sealing dies in mass production.

The counterweight consists of SPHC materials with a thickness of 10mm. Made with regular sealing dies, the edge edge of the part is rough with twisting and deformation.

The slim firing press provides the parts with smooth and vertical cutting edge with precise dimension tolerance. Compared to the regular sealing dies, the design of the dies of the fine blanking type has many differences. Take the vacuum dies for fine type vacuum as an example. There will be v-shaped convex rings drawn around the top plate sealing near the edge of the cutting edge. While empty, the upper and lower plates will tighten the parts. After that, the blank punches will fall to cut the sheet materials. In the meantime, there will be ejecting the same size of perforations by quenching by pressing down to resist the sheet material upwards, ensuring that the cut edge of the sheet material will not bend and deform after cutting. In general, the width of the cracks between the thin-walled perforations and the upper / lower plates will be approximately 0.5% of the thickness of the sheet material. This is almost 1/10 so much the width of the traditional seal cracks dies, so as to prevent the cut edge from tearing.

The pole piece consists of SPHC materials with a thickness of 6mm. Made with a fine type of misery, the edge edge of the part is smooth and vertical, which is not second in quality made by grinding or laser cutting.

With the numerous features above, the thin die type is quite suitable for making two-dimensional parts. Also, when it comes to mass production, fine type averisia has an advantage in its low cost compared to cnc milling and laser cutting. As mentioned above, if we use CNC milling for 2-dimensional parts with precise assembly and cosmetic reasons, the parts will have high accuracy but with high manufacturing cost and low efficiency. If we use laser cutting, although the manufacturing cost is low and the efficiency is high, the dimensional accuracy is lower, only tolerances +/- 0.2mm. Besides, it is easy to have burnt marks, sharp edges, and burrs on the cutting edge when using laser cutting, so we will need secondary treatment to achieve enough precision and cosmetic requirements, and manufacturing costs and procedures will increase further. If you are planning to cut down on construction costs, increase construction efficiency, and have the need for expensive assembly and cosmetic appearance, get the slim formula out there for your plans.

The counterweight consists of SPHC materials with a thickness of 10mm. Made with regularjshoifdhpdsgjjbng dies, the edge edge of the part is rough with twisting and deformation.

For example, the image below is a counterweight to a measuring device. Since the counterweight part is not for cosmetic purposes and its cut edge is not for assembly, it is advisable to use regular sealing dies in mass production. The counterweight consists of SPHC materials with a thickness of 10mm. Made with regular sealing dies, the edge edge of the part is rough with twisting and deformation.

Link：Fine Blanking Press can save 90% of manufacturing costsREF: Cnc Machining Near Me, Aluminum Cnc Milling, Copper Cnc Milling