LED high efficiency, high quality, low cost, the need for comprehensive solutions

At present, the technical development goal of the semiconductor lighting industry is to solve the technical problems of "two high and one low", that is, high efficiency, high quality (including light color quality and reliability), and low cost technology. Only a good solution to these technical problems, in order to provide people with energy saving, environmental protection, health, comfortable lighting environment. To solve the technical problems of "two high and one low", we should put forward the solution from the main parts of the industrial chain, that is, substrate, epitaxy, chip, packaging and application.

Substrate, epitaxial, chip technology continues to break

Global epitaxy, chip companies have 142, China put into operation in 36, to build a family of 25. Global existing MOCVD about 2800 units, China has more than and 700 units, put into operation around 400 units. 2011 global chip production of 82 billion, in 2012 is expected to reach 95 billion, chip production capacity of more than 35%. At present, the white light efficiency of the laboratory up to 254 lm/W, the industry is from 140 to 150 lm/W, Cree recently launched 160lm/W products. At the same time, the blue light efficiency reached 300lm/W, red light effect reaches 240 lm/W, the green light efficiency up to 160lm/W.

The patterned substrate (orientation, NM) and semi polar and nonpolar substrates, by improving the process, simplify the process, save raw materials, reduce the cost and achieved good results; Homoepitaxy, can produce GaN substrate using a variety of methods, and the growth of GaN on GaN substrate LED, greatly reducing the MO source and high pure gas consumption, some people predict the cost can be reduced by 50%.

GaN grown on 8 inch Si substrate, a number of companies have been involved in the development of the world, due to the existing spare production equipment, simplify the process, will greatly reduce costs. At the same time, Aixtron launched Si as the substrate epitaxial furnace, can strictly control the bending, uniform production. This will undoubtedly promote the epitaxial growth process on 8 inch Si substrate, and can significantly reduce costs.

Due to the great reduction of the dislocation density, the new extension technology of Japanese subsidiary company has greatly improved the performance index of LED, and made breakthrough progress.

In the aspect of the chip structure, a variety of new structures have been developed, which is more typical of the hexahedron light-emitting chip, and adopts the multi surface roughening technology to reduce the interface reflection and improve the light extraction efficiency, so as to improve the external quantum efficiency. Samsung Corp using the nano six pyramid structure technology to make the LED, can achieve semi polar, non-polar growth GaN, good heat dissipation, good crystal quality, to achieve a multi colored white LED, a breakthrough.

According to reports, comprehensive, major technological innovation, many epitaxial chip, mostly for improving the performance and reduce the cost of key technical problems, so agency expert analysis predicted that the next 10 years extension costs will be reduced at the rate of 25% per year.

In conclusion, due to the breakthrough of GaN epitaxy, chip technology, using different substrate, nano structure and new technology, the growth of low dislocation of GaN, and make the high efficiency LED. In the absence of wavelength conversion, the light efficiency can exceed 300lm/W (theoretical value of up to 400lm/W); using phosphor wavelength conversion, optical efficiency of more than 200lm/W (theoretical value of up to 263lm/W), but also to develop new technology of single chip multi colored hair. At the same time, the use of new technologies and the growth of epitaxial wafer technology, can greatly reduce the epitaxial, chip production costs.

Modular standard package into the direction of development

China's LED packaging technology has made great progress in recent years, the overall level of packaging and abroad is very small, or even, but the key packaging materials are also imported. In 2011, the global package worth $12 billion 500 million, a growth rate of 9.8%, another report was worth $11 billion 200 million and $13 billion 780 million, but because these institutions lack of Chinese packaging industry estimates (less than $1 billion), so the actual value of global package should be about $16 billion. The world's top ten packaging companies for Samsung, OSRAM, LG, Nichia, CREE, PHILPS, Seoul semiconductor, SHARP, TOYOTA, synthetic billion light, accounting for 68% of the global market. China's packaging device output value of about 25 billion yuan, the output value of more than $100 million in more than 40 enterprises, the device light efficiency of 120 ~ 130lm/W, the use of imported chips, up to 140 ~ 150lm/W.

In order to improve the light efficiency, reliability and reduce the cost of the industry, using SMC composite material, DMS material, high conductivity of various ceramic materials, phosphor coating process and new packaging structure, have made great progress.

[1] [2] next page