Conventional packaging methods and existing applications
LED packaging methods at present are: support row package, chip packaging, packaging of several modules, which are our common and packaging methods commonly used.
Support package is the first by row, to produce a single LED device, this is our common lead-type light-emitting diodes (including Super Flux LED), it is suitable for instrument lights, city lighting engineering, advertising screen, Hulan, traffic light, and relatively common in China now a number of products and areas.
Chip Package (SMD) is a non-lead package, small, thin, very suitable for mobile phone keyboard and display lighting, television backlighting, and the need for lighting or direction of electronic products in recent years, there is the big chip package size and direction of high power, a chip package within three to four led the chip can be used for assembly of lighting products. Multi-chip module packaging is also a package board in the alumina or aluminum nitride to a smaller size, high density packaging packaging dozens or hundreds of LED chips, the internal line is the hybrid type, that is, there are several chips in series, there are several road parallel. This package is mainly to expand the power, used lighting products. Module packaging density of the higher package, the application of heat generated when a large, heat is applied to solve the first problem. Using the above method of production of the device package, for the production of lighting fixtures have a common characteristic: the number of thermal resistance of the channel more difficult to produce high quality lighting, and the module itself is connected with the processing requirements of the radiator is relatively high . All current methods are the yellow phosphor package (YAG) and epoxy resin by mixing different than the column, directly point to the fat blue LED chip, and then heat cured. Advantage of this common practice is to save material, the shortcoming is not conducive to the heat, the phosphor will be aging. Because the epoxy resin and phosphor materials are not good thermal conductivity, and heat will affect the entire chip package. LED lighting for the manufacture of this approach is obviously not the best solution.
Foreign production of high-power chips now, more than 0.5 watts of white light in the blue chips are coated with a layer of uniform chip YAG phosphor slurry, the appearance is a yellow cube looked, (except for welding the two gold pad no phosphor, the method commonly used than the previous method can improve the light efficiency, so widely used in foreign countries.) in the package as long as this kind of white chips soldered on the circuit board to be designed, eliminating the need for coating phosphor deposition process. Lighting manufacturers to bring the convenience, but the current domestic production of chip suppliers such can not be mass-produced white light LED chip.
China Super Flux LED is the early development of the country, in the domestic use was also good, because the national emphasis on "low-carbon economy", 2009, Ten City, ten thousand of the implementation of LED lights, many cities have the experimental section, to test LED lights the feasibility of application of our street is a breakthrough, and abroad (Osram, Nichia, Samsung and other companies) is based on a breakthrough in indoor lighting, these two lines about who has more advantages, has yet to see the outcome. For our part to start with LED street lighting applications, and is caused by conditions because of low income, and LED interior lighting high cost, people can not accept. The use of LED lights is the Government out of money, LED lights manufacturers took a fancy to it. In fact, the working conditions of LED lights LED interior lighting than the more demanding, more demanding, as can be the quality of clearance (heat, life, color, reliability, etc.), then do so in the interior LED lighting is easier to the. LED current foreign giants are rolling out hundreds or even thousands of models of LED interior lighting models, priced at 20-75 dollars, power from a few watts to twenty watts. But their methods are used in packaging mentioned earlier, the only Philips, the phosphor coating on the LED lamp, and was named 2009's most innovative LED lighting products.
I believe that: all of its manufacturing LED lighting should be multi-chip package and the module package (module package is a high-density multi-chip packages), and is best encapsulated in the lamp LED chips directly to the main body, so that the thermal resistance the least number of ways, you can achieve better heat dissipation. Or deposited in the lamps are made of copper foil on the main line body, its thermal resistance is low, LED lighting, a few watts of power over at least, so are the multi-chip used in the packaging process does not apply in the past, must be new methods and technology. LED devices with multiple packaged LED lamps to assemble, difficult to create high-quality and highly reliable LED lamps, LED lamps manufacture want to engage the technical staff can understand this point