In the process of the birth of a chip, lithography is the most critical and complex step. The key is that the essence of photolithography is to transfer the chip circuit diagram on the mask to the silicon wafer, turning the virtual into the real. The most complicated is that the lithography process needs to go through dozens of processes, such as cleaning and drying of the silicon wafer surface, primer coating, spin coating of photoresist, soft drying, alignment exposure, post drying, development, hard drying, etching, detection, etc. < / P > < p > for this reason, lithography, which integrates mathematics, optics, physics, chemistry and many other disciplines, is known as the Pearl in the crown of the semiconductor industry, accounting for about 25% of the total investment in the equipment of the wafer factory. < / P > < p > under the background of tense Sino US relations, this “Pearl” has attracted much attention. It seems that its aura has surpassed other semiconductor devices, and there are voices that as long as we have an EUV lithography machine, the problems of China’s semiconductor industry can be basically solved. < / P > < p > although it is biased to attribute the problem of the whole semiconductor industry to one EUV lithography machine, many problems derived from lithography technology are indeed the focus of industry research all over the world, and also build up relatively high industry barriers. < / P > < p > at the 4th international advanced lithography technology seminar held at the beginning of this month, technical experts and scholars from China, the United States, Germany, Japan, the Netherlands and many other famous enterprises, manufacturers, scientific research institutions, colleges and universities from all over the world jointly discussed the latest technical means and solutions of advanced nodes in the field of lithography. The solutions cover a wide range, including materials and equipment In this paper, the design and optimization of photolithography are introduced. < / P > < p > the wide range of advanced lithography technology solutions is closely related to the properties of the lithography machine itself. If the system of a lithography machine is split, it can be divided into light source system, mask mode system, automatic calibration system, leveling and focusing measurement system, frame damping system, environmental control system, mask transmission system, projection objective system, silicon wafer transmission system, workbench system, whole machine control system, whole machine software system, etc., which means that if you want to have a lithography machine To make the most of its potential, it is necessary for each system to maintain high performance. < / P > < p > take the light source system as an example, up to now, only Cymer and gigaphoton are the real companies selling light source system in the world, and the former has been acquired by amsl, a giant lithography company. At the 4th International Symposium on lithography, Toshihiro OGA, from gigaphoton, said in his communication with the media: “there are many challenges in light source manufacturing. Lithography requires high performance of light source, such as high contrast and pure and defect free imaging quality, as well as cost and reliability control. These things are often difficult to match each other. In addition, from the perspective of customers, usually the light source system is not universal and professional < / P > < p > gigaphoton ships 200 unit light sources every year, of which 80 are used for immersion ARF lithography, 20 are used for ordinary ARF lithography, and the remaining 100 are used for KrF lithography. < / P > < p > in the field of light source system, besides technical barriers, there are also problems of capital and market. Therefore, it is not difficult to understand why there are only two laser light source companies in the United States and Japan 20 years ago. < / P > < p > in terms of materials, mark Neisser, director of science and technology of Xiamen University’s Jiageng innovation laboratory, said that the more top-notch lithography machines, the higher the accuracy of materials, but there is no unified standard for evaluating lithography materials, because each OEM has its own preferences in manufacturing process. The birth of a photolithographic material often goes through customer defined requirements and standards, laboratories or material companies choose chemical materials to make solutions for testing, and some patent problems need to be avoided. This means that, to some extent, lithography materials do not have versatility, which is a major difficulty in the development of lithography technology. < / P > < p > among the global photoresist companies, ASML, Nikon and Canon are among the top three for a long time. With the top technology of upstream suppliers and the huge investment of downstream manufacturers, ASML’s shipment volume ranks first in the world. At the same time, ASML is known as “the only one in the world that can produce EUV photoresist”. < / P > < p > through the above analysis, it is enough to understand the high barriers of lithography technology industry, and the birth of a lithography machine, especially the top lithography machine, needs the cooperation of the global industrial chain, which is difficult to build by the strength of one country. < / P > < p > in fact, at present, only a small part of the chip manufacturing needs to use the top technology such as EUV photoresist, such as 7Nm and 5nm process chips for consumer electronics. Lithography is the key of chip manufacturing, but from the perspective of the whole industry chain, it is not necessarily EUV lithography. < / P > < p > maybe in addition to EUV lithography machine, including etching machine, thin film equipment, testing equipment, cleaning equipment, these semiconductor devices used in common processes are also worthy of attention. Especially with the development of the transistor process, the size of the exposed transistor is larger, so deposition and etching become more and more important in the fabrication of FinFET fin FET. In 2017, the etcher replaced the position of the photoresist and became the most invested equipment in the wafer processing plant. < p > < p > in September 2016, Shenyang Xinyuan microelectronics, a semiconductor equipment manufacturer that mainly manufactures adhesive developing equipment and cleaning machines, successfully delivered the 500th equipment, becoming the first domestic emerging semiconductor equipment manufacturer to cross the factory threshold of 500 equipment, setting a milestone. Since then, Shenyang Xinyuan, as a representative of domestic semiconductor equipment, has been concerned. < p > < p > in December 2019, Shenyang Xinyuan became one of the first listed companies in science and technology innovation board. According to the latest official report of the company, the 900th equipment was successfully delivered on October 30. In the third quarter of 2020, the company’s net profit was 22.6861 million yuan, a year-on-year increase of 4761%. < / P > < p > during the 4th International Symposium on lithography technology, Xie Yonggang, general manager of core source micro front channel business division, gave the experience for other domestic semiconductor equipment manufacturers to refer to. He said: “domestic semiconductor equipment generally starts late and develops late, so it needs to go through a relatively long process of exploration. In the process of exploration, we need to first make a clear positioning, and then seize the opportunity When the time is right, the most important thing is to gain customers’ recognition, which requires good process capability, equipment stability, quality control system and trustworthy after-sales service. ” At the same time, Xinyuan company also said that its competitors are world-class manufacturers. At present, it has introduced some technical experts in the development of top technology and is trying to catch up with them. < / P > < p > however, both lithography equipment and other semiconductor equipment are only one link in the semiconductor industry chain, which solves the equipment problems, and may also need to solve the problems of equipment maintenance, materials, talents and so on. < / P > < p > Liu Xu, Secretary General of the Optical Society of China, Professor of Zhejiang University and director of the State Key Laboratory of modern optical instruments, said at the 4th International Symposium on lithography technology: “the development of China’s semiconductors is not a simple problem. Don’t turn a very complex industry wide problem into a problem with only one local point. Important problems are not the only problems 。” < / P > < p > in addition, for the gap between China’s semiconductor industry and other advanced countries, Professor Liu Xu also thinks: “the design and manufacturing of some devices is a great test of the strength of basic industry. Many times, based on the same principle, other people can do it well, but we can’t do it well. In essence, we lack the understanding of the foundation and the understanding of the limit characteristics of materials.” < / P > < p > at the same time, as to whether China should establish its own semiconductor industry system, Professor Liu Xu said that the construction of the semiconductor industry should not rush on, but should find the right technology, the right people to do it at the right time, and then the country will be able to make it into a line. The current heat of the semiconductor industry is not necessarily a good thing, it is likely to create a crisis As a waste of resources, we need to guard against some interest groups taking this opportunity to plunder social resources. < / P > < p > in the past two years, the semiconductor industry has been booming, and the key technologies represented by EUV photoresist have attracted much attention. Some people think that as long as we can manufacture an EUV photoresist ourselves, the development problems of domestic semiconductor industry will be basically solved, but this is not the case. EUV photoresist is only a miniature of the problems that need to be solved in the development of China’s semiconductor industry. It is important, but by no means the only problem. After 12 years, “world class Super project” Shantou Bay Tunnel ushers in a historic breakthrough today

By ibmwl