In order to obtain high power LED device, it is necessary to prepare a suitable high-power LED panel light chip. The international community is usually a high power LED chip manufacturing method is summarized as follows:
(1) to increase the size of the light
Single LED light emitting area and increase the flow of electricity flow effectively, TCL, through the uniform distribution layer in order to achieve the desired flux. But simply increasing light-emitting area don't solve this problem, heat problem, cannot achieve the desired effect and magnetic flux in practical application.
(2) silicon plate inversion method
Eutectic solder in the first place, to prepare a big chip LED panel lights, and prepare a suitable size, on the silicon substrate and the silicon substrate, using eutectic solder layer and the conductive layer of gold conductor (ultrasonic silk ball joint), and the use of mobile devices described are welded together eutectic solder the LED chip and large size silicon substrate. This structure more reasonable, not only to consider this problem, considering the light and heat, which is the mainstream of high power LED production.
Lumileds company, the United States in 2001 developed a different power of flip chip AlGaInN (FCLED) structure, manufacturing process: the first p-type gallium nitride epitaxial film deposition at the top of the layer thickness of more than 500 a, and returns the reflex Niau ohmic contact, and then selectively etching, using a mask, in the p-type layer and multiple quantum well active layer, N layer deposition, etching after the formation of the N type ohmic contact layer 1 of 1 mm & TImes; 1 mm on one side of the P type ohm contact, n-type ohmic contact with comb into which the chip size, which makes the current extension distance can be shortened, to minimize support and indium gallium aluminum nitride diffusion resistance of ESD protection diode (ESD) of silicon chip installation of solder bump upside down.
(3) ceramic plate inversion method
Universal device of the crystal structure of LED panel light chip of LED chips of the next big, in the ceramic plate and ceramic substrates eutectic solder layer and the conductive layer, in the area of the corresponding wire, welding electrode used in crystal LED chip and large size ceramic thin plate welding, welding equipment. This structure is an issue to consider, is another issue to consider, light, heat, using high thermal conductive ceramic plate, ceramic plate, cooling effect is very good, the price also is lower, more suitable for the current basic packaging materials and the space reserved for integrated circuit integration in the future.
(4) the sapphire substrate transition method
After the sapphire substrate to remove the p-n junction of manufacturers, grow in the sapphire substrate InGaN chips, and then connect the traditional four yuan material, make the structure of the large blue LED chip on the bottom of the electrode, through conventional methods.
(5) AlGaInN method of silicon carbide (SiC) on the back of the light
Cree companies in the United States is the world's only silicon carbide substrate AlGaInN ultra-high brightness LED manufacturers, for many years the production of AlGaInN/SICA chip architecture constantly improve and increase brightness. Due to the p-type and n-type electrode at the top and bottom of the chip, using a single wire bonding, good compatibility, ease of use, thus become the mainstream product development AlGaInNLED another.