LED is a kind of semiconductor diode, it can convert el […]
LED is a kind of semiconductor diode, it can convert electrical energy into light energy, emit visible light of various colors such as yellow, green, blue and other infrared and ultraviolet invisible light. Compared with small incandescent bulbs and neon lamps, it has the advantages of low operating voltage and current, high reliability, long life, and easy adjustment of luminous brightness.
Overhead environmental protection and energy saving dazzling halo: High-power, high-brightness and white LEDs have three outstanding advantages (high efficiency and energy saving, long life, green and environmental protection), and the application field is constantly expanding. The development of the LED industry is in line with China's policy of advocating energy conservation and emission reduction. In the "Eleventh Five-Year Plan", the country listed green lighting as the top ten energy-saving projects.
The LED industry is in a stage of rapid growth, and the inflection point of growth has been reproduced in 2010: since the application of mobile phone backlights has led to the explosive growth of LEDs since 2000, LEDs have gradually entered the fields of automobiles, large and medium-sized LCD panel backlights, and special lighting. Rapid growth and further expansion of application areas; the broad lighting market will become a powerful engine for the advancement of the LED industry. Countries around the world have formulated semiconductor lighting promotion plans, and determined the specific date of incandescent bulb delisting, LED lighting large-scale application is just around the corner. Now that LED technology is developing faster than planned, the highest level has reached the general lighting requirements, and everything is ready but the cost is further reduced. We expect that 2010 will be a year of breakthrough progress in LED lighting.
Opportunities and challenges for domestic LED companies coexist: Many patents in the LED industry will gradually expire in 2010. Domestic companies are expected to break through the intellectual property shackles of European, American and Japanese giants, and use the huge domestic market base and abundant labor resources to occupy a place in the global LED industry.
First recommendation rating: LED industry capital technology is concentrated in the upstream of the industry. Among listed companies, we are optimistic that the business involves the upper end of the industrial chain and the strong bargaining power of Lianchuang Optoelectronics, Sanan Electronics and Silanwei; while considering the huge potential of the LED application market, We are also optimistic about Fangda A and Tongfang shares of LED application enterprises.
Risk hint: Although OLED has shortcomings such as short-lived technical defects and high cost in the short term, the risk of being occupied by OLED in the market still exists.
1. The principle and application of LED
Basic principles of LED
Light Emitting Diode (LED) is a photoelectric element made of compound semiconductor of Group III-V, and its core is PN junction. Under the forward voltage, electrons are injected into the P region from the N region, and holes are injected into the N region from the P region. Part of the minority carriers and majority carriers that enter the opposite region emit light. The nature of the material that forms the PN junction (band gap width) determines the wavelength of the emitted light. For visible light, it determines the color of the light.
The main characteristics of LED are: small size, low power consumption, long service life, high brightness and low heat, environmental protection and durability. Working under proper current and voltage, the service life of LED can be as long as 100,000 hours.
Classification and application of LED
According to the type of light emitted, LED can be divided into visible LED and invisible LED.
Visible light LEDs include red, orange, yellow, green, blue, and violet LEDs. Among them, red LED materials are mainly GaP (binary system), AlGaAs (ternary system) and AlGaInP (quaternary system); blue / white LED materials are mainly GaN.
LED is widely used, mainly including:
1. LED display screens: indoor and outdoor billboards, sports scoreboards, information display screens, etc .;
2. Signal indicator lights: urban traffic signal lights, highway, railway and airport signal lights of major and medium cities in the country, and electronic device function instructions;
3. Light color lighting: outdoor landscape lighting and indoor decorative lighting;
4. Special general lighting: portable lighting (flashlights, headlights), low-illumination lighting (porch lights, house lights, court lights), reading lights (reading lights for airplanes, trains, cars), microscope lights, camera flashes, table lamps , Street lights;
5. Safety lighting: miner's lamp, explosion-proof lamp, emergency lamp, safety indicator lamp;
6. Backlight: LCD monitor, LCD TV backlight.
7. Automobile lights: including interior lighting and exterior lighting. The interior of the vehicle includes the instrument panel, indicator lights of Denso products (switches, audio, etc.), switch backlights, reading lights and external brake lights, tail lights, side lights and heads. Lights etc.
8. Other applications: consumer use, such as children's flash shoes, Christmas tree LED lights, etc.
LED industry chain
The threshold of the LED industry chain from upstream to downstream industries has gradually decreased. The upstream is single-wafer and its epitaxy, the midstream is LED chip processing, and the downstream is packaging testing and application. Among them, upstream and midstream have high technological content and high capital investment density, which is the most fierce international competition and the most risky business area. In the LED industry chain, LED epitaxial wafers and chips account for about 70% of the industry's profits, LED packaging accounts for about 10 ~ 20%, and LED applications also account for about 10 ~ 20%.
Single wafer is the base for manufacturing LED, also known as substrate, mostly using sapphire, silicon carbide, GaAs, GaP as materials. The epitaxial wafer is a single crystal thin film of different thicknesses grown on a single crystal, such as AlGaAs, AlGaInP, GaInN, etc., to realize LEDs of different colors or wavelengths. Common epitaxy methods include liquid phase epitaxy (LPE), vapor phase epitaxy (VPE), and metal organic chemical vapor deposition (MOCVD), among which VPE and LPE technologies are quite mature and can be used to grow general brightness LEDs. The growth of high-brightness LED must use the MOCVD method. At present, the main manufacturers of MOVCD in the world are AIXTRON company in Germany and VEECO company in the United States. The former accounts for about 60% ~ 70% of the international market share, and the latter accounts for 30% ~ 40%. The equipment produced by Japanese manufacturers is basically limited to domestic sales.
Midstream is mainly chip design and processing. Midstream manufacturers conduct device structure and process design based on LED performance requirements, through epitaxial wafer diffusion, then metal coating, then photolithography, heat treatment, forming metal electrodes, and then grinding and polishing the substrate for cutting.
Downstream includes LED chip packaging test and application. LED packaging refers to connecting external leads to the electrodes of the LED chip to form an LED device. The package plays a role in protecting the LED chip and improving the efficiency of light extraction. LED packaging technology is developed from the packaging technology of semiconductor discrete devices. At present, the packaging types of LED products mainly include Lamp type, Through Hole (Through Hole), Surface Mount Type (SMD), Direct Bonding (Direct Bonding) and so on. Among them, the SMD type LED is smaller than other traditional LEDs, so the SMD type is mainly used for mobile phone screen backlight and mobile phone buttons, which is greatly affected by the demand of mobile phones.
2. Introduction to the global LED industry
In 2007, the global LED market totaled more than 6 billion US dollars, an increase of about 13.7% over the previous year. According to isuppli's report, from 2006 to 2012, the compound annual growth rate of the LED global market will reach 14.6%. The main part of the growth is ultra-high brightness and high-brightness LEDs. Isuppli predicts that the total LED market will reach 12.3 billion US dollars by 2012, of which ultra-high brightness LEDs will account for 31% of total LED revenue.
The global LED industry is mainly distributed in countries and regions such as Japan, Taiwan, China, Europe, America, South Korea, and mainland China. Among them, Japan occupies about 50% of the share and is the largest producer of LED industry in the world. Its trend is almost the indicator of LED industry. Japan ’s Nichia is the world ’s largest supplier of high-brightness LEDs, and Toyoda Gosei is the world ’s fourth and Japan ’s second-largest manufacturer of high-brightness LEDs. Osram Opto in Europe and America is the second largest in the world and the largest high-brightness LED manufacturer in Europe. The output value of Taiwan in China is second.
Because Taiwan is a global production base for consumer electronics, its LED industry is dominated by visible light LEDs, and it is currently the world's largest downstream packaging and midstream chip production location.
From 2006 to 2008, the main sources of LED growth are mobile phone backlights, automotive lighting, special lighting (such as landscape lighting, LED display screens, traffic lights, etc.) and backlight sources for LCD panels under 15 inches, LCD monitors and LCD TVs (LCD ) The backlight of the panel was mass produced in 2008. According to Statistics from Strategies Unlimited, the global LED lighting market soared by 60% in 2007, reaching 330 million US dollars. The company expects that the market will total $ 1.4 billion in 2012.
With the rapid advancement of LED technology and the continuous expansion of the market, the international community attaches great importance to the protection of LED intellectual property rights and the formulation of test standards. The main manufacturers use patent advantages to try to control the market by setting up patent barriers and formulating industry standards. Japanese and European and American companies occupy the high-end of the industry and hold a large number of patents. Companies in emerging regions such as Taiwan and South Korea continue to encounter patent litigation from Japanese and European and American companies and are in a passive situation. Japan ’s Nichia Chemical Co., Ltd. had a monopoly position in the LED market with its patent rights covering the LED structure, epitaxy, packaging and process, and phosphors and other related raw materials acquired in the past ten years. It is expected that competition in products and technologies in the global LED field will become more intense as the market expands.
However, as the 20-year patent term is approaching, many LED patents will gradually expire in 2010. At that time, the original industrial patent structure will undergo major adjustments. Emerging manufacturers are expected to gain new opportunities for development. At present, LED manufacturers with a large number of patented technologies have launched mutual authorization methods to circumvent the patent problem, and use the original scale advantages to vigorously develop new patented technologies. Therefore, for emerging industries such as domestic LED manufacturers, patent expiration is both an opportunity and a challenge. Domestic manufacturers with upstream technical capabilities such as epitaxy, LED chip design and manufacturing are more likely to seize the opportunity to make breakthroughs in epitaxial substrate and chip technology, reverse the unfavorable professional pattern, and benefit from a new wave of restructuring trends in the LED industry By.
Energy saving and environmental protection, the general trend
At the same brightness, the LED power consumption is only 1/8 of the incandescent lamp, 1/2 of the energy-saving lamp, and the life can be extended by nearly 100 times, up to 100,000 hours; if all the general lighting uses LED lamps, China can save electricity every year Nearly 100 billion degrees, equivalent to the power generation of a Three Gorges project. In addition, the LED does not contain mercury, lead and other harmful elements, and the light does not contain ultraviolet and infrared rays, which is harmless to the human body.
The three well-known European Union environmental protection laws on electronic products have made hard regulations on the environmental protection of electronic products. The Waste Electrical and Electronic Equipment Directive (WEEE) was formally implemented in August 2005. The purpose is to reduce the amount of waste electrical appliances, increase the recycling of waste electrical appliances, and improve the environment. "Framework Directive on the Development of Environmental Design Requirements for Energy-using Products" (EuP)
Was released on July 22, 2005 and will take effect 20 days after the release date. The directive covers a wide range, and the European Commission will successively formulate specific implementations of energy-using products such as heating and hot water equipment, electric motor systems, furniture and commercial venue lighting systems, household and office office equipment, personal electronic products, etc. according to the EuP directive Measures.
The Directive on Restricting the Use of Certain Harmful Components in Electronic and Electrical Equipment (RoHS) was formally implemented in July 2006, and its main purpose is to eliminate lead, mercury (mercury), cadmium, and hexavalent chromium in electronic and electrical products , Polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE) a total of six substances; according to the RoHS directive, general lighting sources containing lead (such as fluorescent lighting) will be discontinued in 2011.
In addition, the "Kyoto Protocol" adopted by 149 international and regional governments in February 2005 entered into force. Its goal is to reduce the emissions of six greenhouse gases, including carbon dioxide, methane, and nitric oxide, in developed countries from 2008 to 2012. On the basis of 1990, the average reduction was 5.2%.
LED lamps do not contain harmful substances such as lead and mercury, without strobe, and are green light sources; and the use of LED lighting can greatly reduce the demand for electricity and further reduce greenhouse gas emissions. With the strengthening of global energy conservation and environmental awareness, the topic of energy conservation and emission reduction has been continuously strengthened. Many countries and regions in the world have introduced policies to support the development of the semiconductor lighting industry. The environmentally friendly and energy-saving LED industry will shine.
3. Overview of domestic LED industry development
After more than 30 years of development, China's LED industry has initially formed a relatively complete industrial chain, covering all aspects of LED substrates, epitaxial wafers, chip packaging and applications. In the domestic LED industry chain, the development of epitaxy and chip links is relatively lagging behind. There are only about 10 domestic companies engaged in the production of LED epitaxial wafers, and there are not many factories engaged in the production of LED chips, and the concentration of production capacity is relatively high. The main reason is the lack of independent intellectual property rights and core technologies in China, the backward production equipment and the unsmooth industrialization of scientific research achievements. MOCVD is the key equipment for making LED epitaxial wafers, and China's MOCVD equipment manufacturing is in the stage of technology tracking and cannot be adapted to production. The price of imported production MOCVD equipment is as high as 10 to 20 million yuan, which limits the development of the domestic upstream industry to a certain extent. In December 2007, there were more than 80 MOCVDs in China, of which there were more than 50 production-type GaN MOCVDs and about 10 quaternary MOCVDs. According to the investment plans of various manufacturers, China expects to add more than 40 MOCVD units in 2008, and the scale of domestic and foreign extended chip production capacity will be greatly improved.
According to the statistics of China Optical Optoelectronics Association, China's chip output value in 2007 was 1.5 billion yuan, an increase of 43% from 2006's 1.05 billion yuan. It is expected that the average growth rate of domestic chip production capacity will be over 30% in the next few years. In 2006, China's LED device packaging market was 14.6 billion yuan, an increase of 15% in 2007, reaching 16.8 billion yuan. In 2007, the market value of China's LED application products has exceeded 30 billion US dollars. Among them, China's high-brightness LED market in 2006 was 9 billion yuan, and it is expected to grow to 28 billion yuan in 2010. It is estimated that by 2008, the output value of the domestic LED industry will exceed 150 billion yuan.
LED epitaxial wafers and chips have extremely high technical requirements. There is still a certain gap between China and the international advanced level in these two aspects. At present, the output of wafers and chips at home and abroad is limited. The output of epitaxial wafers can only meet 20% to 30% of the demand of packaging companies. Many chip manufacturers in the mainland must purchase epitaxial wafers from foreign countries and Taiwan for processing. The major domestic LED epitaxy and chip companies are: Xiamen Sanan, Dalian Lumei, Hangzhou Silan Mingxin, Shanghai Blu-ray, Shenzhen Fangda, Jiangxi Lianchuang, Shenzhen Century Jingyuan, Tongfang etc.
The production of LED application products in China in 2007