【正文】 te lightSingle grain product white light,Other to be done to be doneMultigrainGreen, blue amp。 red, green and blue multicolor binationsHigh luminous efficiency。 can be dynamically adjusted colortemperature。 of good color。 natural colorThe needs of three grains, the grain of the need for individual electronic circuit design, high cost。 poor of the closeup color。 multicolor LED lightemitting efficiency is not evenAs a result of blue light chips + YAG phosphor have a white LED production method of the lowest cost, practicality39。s characteristic has bee the mainstream products on the market. Therefore, the experiment chosen this method to product white LED.Key processes and technical measures Compared with the ordinary whitelight LED, the highpower (Wclass power) white LED has a higher power and more heat, therefore, in the packaging process, be considered light, electricity, heat and other factors.Flipchip technology Installed in the traditional way of LED chip package, because of Ptype doped GaN difficulties, the current widely used in the preparation of Ptype GaN metal transparent electrodes on the ways in which even the spread of current in order to achieve the purpose of lightemitting uniformity. Ptype GaN on the transparent electrode metal to absorb 30% to 40% of a light, while ntype electrode and the lead will block some of the revealing light, which severely affect the chip LED light efficiency. In the manufacturing process, in order to improve light efficiency, generally transparent electrode metal thinning methods, so that in turn limits the current in the hGaN surface evenly spread the impact of the product39。s reliability, constraint of the LED chip operating current . At the same time, such a structure is installed through the PN junction calories derived sapphire substrates, sapphire is the thermal conductivity 35 W / (mK) (worse than the metal layers), a larger thermal resistance, resulting in bamboo core temperature rise, thus affecting the device the performance.This experiment, to take advanced flip chip (flipchip) technology, through the Pchip and n very very bottom of the production of ultrasonic gold wire leads to solder joint as the electrode structure and the outside of the Si chip on the production floor gold lead, to overe the abovementioned LED chips are mounted in a light efficiency and the shortings of current constraints。 chip PN junction from the heat generated by gold wire solder through a direct transfer to the Si substrate and heat sink, the heat transfer is far superior to the effect of Sapphire is mounted cooling structure。 flip chip solder ball structure of the gold wire to shorten the path, avoiding the chips installed in the traditional structure is a result of a long wire path phenomenon resulting from high fever。 At the same time, the production of Si substrate reverse bias the PN junction, the realization of Si substrate and the Cu heat sink electrical isolation between。 thus Increased product life LED, so that package greatly enhance the reliability.Optical design techniques1. To improve the refractive indexHighpower white light LED chip refractive index of n = 24, much higher than the lens plays a role in the refractive index of packaging materials (generally of the refractive index of epoxy resin at about ). Therefore, when the light after the chip packaging materials, in a total reflection from the interface effect occurred, resulting in about 50% of the light reflection back to the chip itself, can not be effectively exported to bee ultrahigh brightness LED chi