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Several methods of making high power LED chip

From: Data:28/08/2016

to get high power LED devices, it is necessary to prepare a suitable high power LED chip . Internationally, the usual methods of producing high power LED chips are as follows:

large size method. By increasing the monomer led the effective emitting area and size, prompted through the TCL layer current uniform distribution, in order to achieve the expected flux. However, simply increasing luminous area cannot solve the problem of heat and light, did not reach the expected flux and the practical application effect.

flip chip method. First prepared for eutectic welding of large size led chip. Simultaneously, the prepared the corresponding size of the silicon plate, and on the silicon base plate making for eutectic bonding with the metal conductive layer and leads to the conductive layer (ultrasonic gold wire ball solder point), the eutectic welding equipment, the large size led chip and the silicon base plate is welded together. This structure is more reasonable, not only consider the issue of light, but also take into account the heat dissipation problem, which is the mainstream of the current production of high-power LED.

Lumileds company in 2001 developed AlGaInN power type flip chip (FCLED) structure, its manufacturing process is: firstly, NiAu layer deposition thickness P GaN in epitaxial films on the top of more than 500A, used for ohmic contact and back reflection; then the mask etching P layer and multi quantum well active layer select the N type, exposed by etching, deposition layer; the formation of N type ohmic contact layer, the chip size is 1mm× 1mm, P type ohmic contact for the square, N type ohmic contact to comb into it, this can shorten the current expansion distance, extend the resistance to the minimum; and then the metal bump AlGaInN chip in the flip chip with antistatic protection diode (ESD) silicon carrier.

ceramic floor upside down method. First use of LED chip Universal equipment manufacturing to prepare for the eutectic welding electrode structure of a LED chip light area and the corresponding ceramic floor, and on the ceramic board made eutectic welding conductive layer and leads to the conductive layer, then using eutectic welding equipment, the large size led chip and the ceramic board is welded together. This structure takes into account both the problem of radiation heat problem is also taken into account, and the ceramic plate is a ceramic plate with high heat conductivity, heat dissipation effect is very ideal, the price is relatively low, so suitable floor material in the current and future product integrated circuit package of body reserve space. The

sapphire substrate transition method. In accordance with the conventional InGaN chip manufacturing method grown on the sapphire substrate PN junction, removal of the sapphire substrate, and connected to the traditional four element material, manufacturing a lower electrode structure of large size led blue chip.

and AlGaInN silicon carbide (SiC) on the back of a light. American Cree company is the world's only using SiC substrate manufacturing AlGaInN super high brightness LED manufacturers, for several years the structure of its production of AlGaInN/SiCa chips continue to improve, brightness increased. Because the P and N electrodes are located at the bottom and top of the chip, the use of single wire bonding, good compatibility, easy to use, and thus become another major product of AlGaInNLED development.