From 65438 to 0968, the first batch of domestic light-emitting diodes (LEDs) began to enter the market. Up to now, it has been more than 30 years, and it has great influence in emerging industries of optics and optoelectronics, and has always occupied a place in the field of display technology. In the development of electronic basic products, China government insists on establishing the concept of big market, takes the modernization and informatization of the national economy as the goal, and strives to realize the specialization and large-scale production of products and expand the ability of earning foreign exchange through export. Five new electronic components, such as photoelectric devices, are given priority as development goals. LED industry is the focus of the development of optoelectronic devices, which has advantages in output value, output and scale effect. Although it occupies a small share in the world's photoelectric design, China's huge market potential makes manufacturers participate in it, expanding investment and increasing production capacity.
In recent three years, the average growth rate of LED industry has been above 30%, especially after 1996. 1998 achieved a sales income of 2.244 billion yuan, an increase of 13.44% over the previous year, and the output was 6.509 billion pieces, an increase of 5.2% over the previous year, with an output value of 3.589 billion yuan. According to industry data, at present, there are more than 100 units engaged in production, management, scientific research and education in China, with about 15000 employees, of which 20% are engineers and technicians, and the industry assets are 350 million yuan, which has initially formed an industrial scale. At the same time, industrial development has also promoted the development of surrounding supporting industries. Except for LED chips, the main raw materials, spare parts and required instruments and equipment are produced and supplied in China. Many universities and research institutes in China have done a lot of research work on luminescent materials, new structures, new devices and new applications, and achieved a lot of results. During the period of 1998, scientific research and development were completed, and more than 250 technological innovations were made, some of which reached the international advanced level. Among many manufacturers, there are more than 20 honest packaging factories, such as Lianchuang and Foshan Optoelectronics, Ningbo Amida, Xiamen Hualian, Tianjin Tianxing, Suzhou Semiconductor and Shenzhen Liang Chao. There are five chip manufacturers. Nanchang Xin Lei Company is the only chip manufacturer that can supply chips in bulk at present, with a monthly production capacity of 200KK. It is reported that the company is making an expansion plan with a monthly target of 200,000 pounds. It is reported that the company is drawing up an expansion plan with a monthly production capacity of 500,000 tons. The successful operation of Xin Lei Company has changed the situation that China's chips only depend on imports. The production of Jing Tian is encouraging. But after the operation, it went through a painful course of cooperation. Recently, there has been a turnaround, saying that the production of traditional LED chips is in short supply and the market is tight. However, it is far from mass production, and the other three manufacturers are still in the trial production stage, with few listed products. Four-dimensional chip manufacturing, there are also three companies to invest, so far no output sales; There are six manufacturers engaged in R&D and production of luminescent materials, among which three factories make epitaxial wafers of traditional chips and three factories use MOCVD technology to make four-dimensional materials. At present, little progress has been made, and they are all in the experimental stage.
LED display screen is one of the main applications of light-emitting diodes, which has developed rapidly in recent years. At present, the manufacturing technology of LED display screen is advanced and the price is low, so it is difficult for foreign-funded enterprises to compete in the mainland market. According to incomplete statistics, in 1998, there were more than 150 LED display manufacturers in China, manufacturing about 50,000 square meters of various displays, achieving an output value of 6,543.84 billion yuan. The outdoor screens and full-color indoor and outdoor screens produced by major manufacturers such as Beijing Lantong, Nanjing Luopu, Lianchuang Jianhe, Shanghai Xinmao, Shanghai Sansike, Northeast Microelectronics, Xi 'an Songqing, Tianjin Data and Shenzhen Tongzhou can be accepted by users and promote the development of the information display market. Taiwan Province, China has made remarkable achievements in developing LED industry. In recent years, it has kept ahead of Japan in terms of product structure, manufacturing technology, product quality, mass production level and market share, ranking third in the world's LED industry after the United States and Japan, with an average annual growth rate of over 20% in recent five years, ranking fourth among the top ten photoelectric products in Taiwan Province Province from 65438 to 0997. Epistar Corp has an output value of NT$188.7 million, and successfully developed red, green and blue chips for full-color lamps and displays, with the light intensity of these chips exceeding 70mcd. A company in production uses MOVPE technology to produce InGaAlp super-bright luminescent materials and chips. There are 7 enterprises producing LED chips in Taiwan Province Province, and the output of various traditional chips accounts for more than 70% of the global output. The main manufacturers are Guanglei, Dingyuan, Guangbao and Guolian. Famous photoelectric companies in Europe, America and Japan also use Taiwan Province chips. There are more than 30 packaging plants in Taiwan Province Province, and 10 is a big company, mainly Guangbao, Yiguang and Jintai. Most of these manufacturers set up factories in the mainland to expand their production. Therefore, the overall strength of China's LED industry is strong, and it is expected to become an important pillar industry of electronic basic products.
Light emitting diodes are widely used. Because of its low working voltage, low power consumption, rich colors and low price, it is welcomed by electrical engineers and researchers. Early traditional products have low luminous efficiency, and the light intensity is usually tens to tens of MCD. They are suitable for indoor applications such as household appliances, instruments, communication equipment, microcomputers and toys. Due to the development of application technology, traditional products have new application opportunities, and the popular LED Christmas lights, including duck-billed Christmas lights, colorful ball lights and pearl window lights, are rich in color, unbreakable and safe to use at low pressure. Recently, it has been sold strongly in Southeast Asia such as Hong Kong, which has been widely welcomed by people, threatening and replacing the existing electric bubble Christmas market. A kind of flashing shoes that are very popular with children. When walking and sleeping, they flash with LED, which is very eye-catching, with both monochromatic light and bichromatic light. According to the general manager of a shoe enterprise in Zhejiang, 500KK light-emitting diodes are used in Wenzhou alone for one year. Toothbrushes with health care function are widely used in developed countries, and it is very convenient to use light-emitting diodes as indicators of toothbrush power. Each toothbrush is equipped with LED lights. According to the domestic manufacturers who are putting into production, the company has a small number of health toothbrushes on the market, and it needs 300KK light when planning production. In terms of industrial products, LED-type AD 1 1 indicator lamps are widely used in power cabinets. The product adopts multi-chip integration to form a light source, which has three colors: red, yellow and green. After the capacitor is depressurized, 220V and 280V power supplies can be used. According to a manufacturer in Jiangsu, the company's annual sales volume is above 10k, and it needs 200 KK-300k every year. The market still has the potential to expand. Because of its clear indication of active luminescence, long service life and low power consumption, it is very popular with users, and will soon completely replace the bubble AD 1 1 product. In short, the market of traditional LEDs will not only improve with the growth of original products, but also open up market opportunities with new applications.
With the development of new materials and semiconductor industry technology, since 1994, new visible light materials InGaAlP and InGaN have become the mainstream, achieving high brightness and multicolor. In addition, with the improvement of packaging technology, the amount of display information is increasing, and new application fields of LED products are constantly emerging, bringing more market opportunities. These products extend the application of LED from indoor to outdoor, and can be clearly displayed in strong sunlight. The luminous efficiency is extremely high, and the light intensity exceeds 1000mcd, which meets the requirements of full-color display and low power consumption of portable products. These advanced LEDs include:
1. Blue and green led: Blue led is made of ternary materials such as silicon carbide (Suc), gallium nitride (GaN) and indium gallium nitride (InGaN). The blue led with InGaN/AlGaN structure has a peak wavelength of 470nm and a normal light intensity of 2000mcd, while the green led has a peak wavelength of 520nm and a normal light intensity of 5000mcd. Among them, there is a blue-green (traffic green) light with a peak wavelength of 500nm. On the basis of blue light, a few milligrams of fluorescent substances are added to the chip to make it turn white when packaged. White light diode is the best substitute for miniature incandescent lamp. Although it is more expensive than an electric light bulb, it is not easy to break down, saves more electricity, hardly generates heat when working, and can continuously illuminate for more than 10 years. These products are produced by famous photoelectric subsidiaries in Japan, Germany, the United States and Taiwan Province Province.
2. A new type of quaternary light emitting diode: GaAlAs material, which was developed and marketed in the late 1980s and made into a red light emitting tube. At first, it meets the requirements of ultra-high brightness, and the luminous intensity exceeds 65,438+000 MCD, but the light attenuation is large and the application range is limited. The products made of InGaAlP quaternary materials successfully developed in 1990s can obtain four colors of red, orange, yellow and amber, with high luminous efficiency and good high-temperature performance.
3. New varieties of 3.LED and power light-emitting diode: it works at 70ma, emits a strong light beam with a large viewing angle, generally 40-70 degrees, and is used as a car sign lamp; SMD)LED works at a low current, generally 1-2MA, and the brightness is enough to save the power consumption of portable products. Constant-voltage light-emitting diode (LED), the resistor is encapsulated in it when it is manufactured, and the current-limiting resistor is not needed when it is used. Generally, it works below 12V, which is very convenient for users. Similarly, when packaging, an integrated circuit is put inside, which generally works below 5 V. It will flash and glow when it is electrified, which can be used as a status display and is very convenient to use. Such clustered LED chips, devices and elements can be made into light-emitting modules to achieve specific functional requirements, and
The appearance of these new devices expands the application field of LED. 1. The application of traffic signal display light source has the characteristics of earthquake resistance, shock resistance, fast light response and long power saving life. There are about 1 1 manufacturers developing traffic lights in China. Among them, three companies' products have passed the testing of certification bodies, and traffic lights have been tested in Beijing, Shanghai and Tianjin recently, with the number of 1997. Secondly, it is used in the automobile industry. Incandescent lamps used in automobiles are not resistant to vibration and impact, easy to be damaged, short in service life and often need to be replaced. Starting from 1987, China began to install advanced brake lights on cars. Because of the fast response speed of LED, drivers can be reminded to brake as soon as possible, which can reduce rear-end collision accidents and increase safety. In developed countries, all light sources in automobile dashboard and various lighting components can provide ultra-high brightness luminous lamps. The central rear high-position brake light made of LED has become the standard of automobiles. The LED taillight module introduced by Hewlett-Packard Company in the United States in 1996 can be combined into various taillights at will. The third is LED backlight, especially the backlight with high efficiency side light emission. As the backlight of LCD, LED has the characteristics of long life, high light output efficiency, no interference and high cost performance, and is widely used in electronic watches, mobile phones, BP machines, electronic calculators, card readers and so on. With the miniaturization of portable electronic products, LED backlight has more advantages, and mobile phones choose LED backlight. Therefore, the backlight production technology will develop towards thinner, lower power consumption and uniformity. The thickness of the backlight board on the LED side can reach 0.7-3.5mm, and the luminous efficiency can reach 50-70%. In addition, customers can choose green, red, blue and various mixed colors, and ultra-thin backlight with the same thickness as EL may appear soon. The fourth is the LED lighting source that people are most interested in. The direct goal is to replace incandescent lamps and fluorescent lamps with LED light sources. This trend has been replaced from local areas and from small to large. Japan's Ministry of International Trade and Industry has called on the whole country to save energy, and is planning to replace incandescent lamps with led projects (called the Lighting Japan Project). It is estimated to be 5 billion yen in the first five years. If led is used to replace half of incandescent lamps and fluorescent lamps, the energy equivalent to 6 billion liters of crude oil can be saved every year, which is equivalent to the power generation of five 1.35× 106KW nuclear power plants, and the production of greenhouse gases such as carbon dioxide can be reduced and people's living environment can be improved. Therefore, people are facing the lighting reform and expect LED to bring people good news.
With the continuous emergence of new technologies, new products and new applications in LED industry, the sunrise industry is thriving. I believe that in the first decade of the next century, the LED industry will continue to develop:
1. Manufacturers will increase investment in ultra-bright full-color technology, increase production capacity and increase the number of employees. China (including Taiwan Province Province and Hongkong) will become the main led producing area in the world, accounting for more than 60% of the world total. After five years, the output value will reach 7 billion yuan, the ultra-high brightness led will increase by 30%, and the traditional led will also have 5%- 10.
2. At present, many light-emitting diodes with different colors have reached the candlelight level. It is believed that with the improvement of device structure and the rapid improvement of luminous efficiency, the main direction of LED development in the future is to replace incandescent lamps in some fields, and during this period, people are faced with the reform of lighting sources. It is predicted that LED will become the lighting source in 2 1 century.
3. The development of the world optoelectronic industry has promoted the change and development of the application field. It is believed that with the development of LED industry, more funds will be invested in the R&D and production of LED. Therefore, the monopoly of the existing ultra-high brightness, blue and green LED technology on a few manufacturers will be broken, and the product cost is expected to be greatly reduced, thus promoting the re-development of the market and the re-expansion of applications.
It is believed that semiconductor light-emitting technology will not be replaced by other technical products, and will continue to develop along the original track.