Shaoxing Xinshan Science Technology Co.,Ltd
Address: Dongfangyimai, No. 2, Pujiang Road, Shaoxing, China
LED chips are often referred to as the "heart" of LED lights, and their quality is directly related to the quality of LED lights and even LED displays. The current heat of small spacing LED creates opportunities for domestic LED chipmakers and challenges. Special in LED chip, the author specially invited hangzhou silan Ming xin technology co., LTD., HC Semitek Corporation, the three photoelectric co., LTD., and crystal ingots light electric (shenzhen) co., LTD., xiamen dry as photoelectric co., LTD., and other enterprises to discuss the relevant personage, a snapshot of the LED chip manufacturers in the new situation of the road of "core design core manufacturing".
1. At present, in the field of LED display, small spacing is becoming the mainstream of industry development, and the trend is becoming more and more obvious. What opportunities and challenges do you think the rapid development of small space will bring to domestic chip manufacturers?
General manager jiang zhongyong:
This year's small spacing is indeed growing, but it is widely believed that growth has been slow. With the use of small Spaces in the area of the display, the number of them will increase, and the fact that this is the case is necessarily higher requirements for product quality. Relative to enterprises, how to solve technical problems and improve product performance and quality is the key to survival, development and expansion of enterprises. Many enterprises seize the opportunity of the development of the small spacing, press on the small distance between the difficulty in the products, the main points of a good problem solving, thus produce recognised by the market of high quality products, the enterprise will achieve better survival and development opportunities, the opposite may make the enterprise into a passive situation. At present, the quality of the packaging and the quality of the chips has not yet reached a perfect state. Therefore, continuously improving the quality and stability of the packaging and chip are still a long way to go for small distance enterprises.
Shi songgang, director of optoelectronics marketing:
The small spacing LED display technology will show explosive growth in the coming years with its unspelt and excellent display effect. Display because of its small spacing distance more close and the demand for chips will increase, and now the whole market capacity in rising, visible in the future there will be a lot of room for growth, it is a good opportunity for chip companies. But the small spacing display has higher technical requirements for the chip, such as: how to achieve the consistency between small current and small capacitance of LED display? How to better satisfy the high quality of low - light high grey? This requires chip companies to continuously improve the epitaxy and chip technology to meet the demand of the market, and only those enterprises with hard technology can stand out in the market competition.
Guo yuntao, manager of SAN 'an optoelectronic product planning department:
The development of the small spacing screen means that the chip package will be smaller and the layout will be more dense. For chip sizes, miniaturization requirements and other photoelectric features require more stringent requirements.
Wang junbo, vice President of jinyuanbao Chen:
At the moment, the domestic LED display area is already fast in the whole, especially the small space this chip application market, its integration speed is more rapid than other application market. For chip companies, including crystal electricity may be three to four major, I think this should not have too big change, because the market through the whole and the development has been mature, concurrently Evergrande, again want to get into this field, it is not so easy. The number of small spacing display chip is more, and the crystal power is optimistic for the application development of small spacing display screen.
Mr. Zhang yong, chief engineer,
One of the hallmarks of small spacing displays is the densification. The high density will definitely increase the use of LED chip, which means that the increase of market demand will undoubtedly bring new opportunities to LED chip manufacturers. , of course, with the decrease of the distance between the chip, also put forward higher requirements for the chip: how to make the LED chip has better consistency, reliability, but also meet the low light, high ash, high refresh rate, high scan application requirements, this gives the LED chip manufacturing enterprises brings new technical challenges.
2. The small spacing products are highly integrated, and there are more and more lamps in the unit area. How can you improve the design of the chip and improve the photoelectric conversion efficiency of the chip?
Display products for small spacing, it is because of containing the lamp bead more and more, so it of single lamp bead brightness demand is more and more low, chip photoelectric conversion efficiency is no longer the focus of attention.
This year, the company has pioneered a small space dedicated X series chip in the industry. The series of the direction of the chip design is: the new optimized extension and chip technology, to realize in wide Angle of view, high refresh and low light high ash quality such as the pursuit of better display effect, wide Angle light consistency, small current photoelectric consistency, small capacitance on consistency and reliability of the highest in the industry standard set X series chips in the quality standard of the industry, reduce the death rate of light, to ensure the stability of the screen.
For the display, the main requirement of the chip is to improve the damage caused by the chip during the high brush, so it is more likely to focus on the reliability of the chip.
We always have the misconception that LED products must be brighter and better. In fact, the focus of the small distance product is not necessarily in the brightness. Because in many cases, it is necessary to have low dark degrees to render the effect. To chip side view, the question is not out of the photoelectric conversion efficiency, but the display screen and other applications is different, he is not rated current operation, the current switch when how to let the brightness of the chip and wavelength can be stable, in the small current when how to make the chip to maintain performance, this is our homework.
The photoelectric conversion efficiency of the chip is improved through the two aspects of epitaxial structure and chip process optimization. For example, in the aspect of chip manufacturing, improve the cutting process, increase the luminescence area of the chip, improve the uniformity and efficiency of the lateral luminescence. In addition, by epitaxial structures and materials optimization of growing conditions, improve the internal quantum efficiency of LED chips, as well as the optimization of material selection and thickness in each layer, the content of the optical match, the LED has higher light efficiency.
3. Compared with blue and green chips, the development of red light chip technology is slow, and the efficiency of photoelectric conversion is still to be improved. To match the blue and green chips, the red chips often need to turn up the current. In the small spacing area, the power consumption is larger, and the product temperature is higher. How can your company promote the technological innovation of red chip and change this disadvantage?
General manager jiang zhongyong:
The problem of using red light to enhance brightness is, technically, completely broken and resolved. But in red light there are two kinds of red light: one is positive and one is negative. Then the red light of the reverse polarity will be twice as bright as the red light of the positive polarity, but it will be relatively high. Blue and green chips are cheaper to use and also brighter. In the small space: the choice of chips is small, the cost is low, many enterprises emphasize the cost, but do not emphasize the quality and reliability of the products. So, in general, there is no choice to highlight red, and most of the red chips are in positive polarity, and there are some difficulties in changing that.
In the past two years, red light AS chip has been progressing slowly in brightness. Different from the brightness of GaN epitaxial films, the internal quantum efficiency of the four-yuan red light epitaxy is already high, and there is no room for improvement. Factory market by wafer bonding and substrate transfer technology to make the reverse polarity of the chip (N electrode) upward while higher brightness, but the high cost of expensive and also faces certain VF in terms of chip size miniaturization high question, is not suitable for small spacing display applications. Our countermeasure is to improve the quaternary red DBR reflection efficiency of epitaxial wafer and the surface roughening technology, improve the external quantum efficiency, our small spacing display red chips in the same size in brightness than 15% higher than other manufacturer, which can effectively reduce the electric current to reduce fever.
At present, for the red light part, it is continuously improving brightness and design in its process, and the design and development should be carried out with the blue and green chip.
A red wafer photoelectric product conversion efficiency with blue light is almost the same, the RGB display screen, red, blue and green three chips are used together, when red hot originally light failure will be more than blue, so we want to increase the current independently. The brightness of the three chips will be uniform when they reach the thermal state. Therefore, the red light should increase the current. This is not the efficiency of the chip, but the difference between the material characteristics. Wafer of creativity and innovation for the sake of customers always run in the front, AX series of PN series two technology platform and complete product line, not only to provide chips, also provide solutions and technical support, for customers to create more added value.
As is known to all, wafer issued WPE75 % infrared products reach the world's first, there is another the first it is a red wafer product capacity (the world), excellent product performance is the world's level, and in addition to RGB display screen a wider application of import car tail lights, car reliability and reliability requirements of the chip should be all LED the application of the highest and most demanding, so more checkered crystal electric red chip quality and public praise. In addition, the wafer with complete patent layout, since its establishment in 1996 has been absorbed in red light product innovation, constantly strive for excellence, to do the industry first, the capacity is the world's first big degree, also depends on customer's use and absolutely sure.
By optimizing the structure optimization of red LED chip, the photoelectric conversion efficiency of the red chip is improved by improving its manufacturing process. Absorbing blue-green LED chips, for example, some of the technology, improve the current extension of red light LED chip layer, increase the current blocking layer, increase the reflective electrode and other means to improve the current extension ability of the LED chip, the LED chip light more even and has better temperature distribution at the same time, improve the heat dissipation characteristics, to further enhance the photosynthetic efficiency of the red LED chips.
4. At present, the pace of innovation of industry development is obviously accelerated, with small spacing, indoor appearance stickers, permeable screens and alien screens speeding through the whole industry. As an important link in the whole industry chain of LED display, how do you think chipmaking enterprises should keep up with the rapid development of the industry? What should I do? What is the development trend of LED chips in the future?
General manager jiang zhongyong:
Differentiation in chips is harder to do. Because people in the chip flow more frequently, it is difficult to make a big difference in technology or program. For silan Ming xin, we continuously detailed, mainly on the quality management so as to improve the quality of the chip, make produce chips on the stability of the edge, to ensure minimum issues to market products, rather than blindly pursue variety differentiation or other differences.
First of all, for chip companies, chip product needs both meet the needs of existing market segment, also want to meet future demand for emerging market technical reserves, ready to respond to market changes, to provide customers with non homogeneous products. The product ADAPTS the market to the long term.
Second, enterprises should hard skills, cooperate with encapsulated customer and application. Starting from the application, from the aspects of equipment, materials, structure, process of system innovation, to build industry chain cooperation and coordination with marketing and cooperative promotion, integration of upstream and downstream resources, provide the end user system solutions.
Whether outdoor or indoor, the future must be to the small space screen development. For outdoor chips, in addition to the small spacing trend, there is a trend towards energy conservation.
Technical problem is every enterprise main attack direction: including overcome Yang green, color monogamous problems. When you do small spacing, you will find that the patch this thing is very, very expensive. At present, there is also a part of the enterprise, including crystal electricity try other methods in technology production, to find a new breakthrough. In the short term, but from the perspective of a current form, 1 to 2 years should also won't appear the industrialization production pattern.
As LED chip manufacturing enterprises, we should be close to the market and close to customers, and can respond to the new technology and new requirements of packaging enterprises in a timely manner. Anticipate future trends and advance some forward-looking research and development. For example, the customer has adopted new line equipment or new wire, and improved the line technology, which can make the electrode of LED chip further small. The chip enterprises also need to adjust the electrode process in time to meet the customer's demand, and improve the performance of the LED chip while lowering the cost. In the future, with the further reduction of the spacing of LED display chips, it is necessary to minimize the space occupied by the line. The use of flipchip should be one direction of future LED chip development.