Development status of CVD diamond in China

In China, research on CVD diamond began in the mid-1980s. Professor Zou Guangtian of Jilin University was sponsored by the research team of the Jilin Provincial Science and Technology Commission in 1985 to start research on diamond film. In April 1987, the first domestic diamond film was prepared by hot filament low-pressure CVD.
China began to implement the National 863 Program in 1987, when the plan was divided into seven areas. Among them, diamond film research topics are listed in the field of new materials technology. In 1987 (seventh five-year project), four units including Jilin University, Institute of Artificial Crystals, Sichuan University and Beijing Institute of Technology undertook the research and development of diamond film by the 863 expert group. The implementation of the National 863 Program provides a good opportunity for the development of diamond film research in China. During the period of the Seventh Five-Year Plan, China's research on diamond film has made great progress and has attracted the attention of international counterparts. Since then, many units in China have started research on diamond film and set off the research heat of diamond film. During the Eighth Five-Year Plan (starting in 1991), the research on diamond film was promoted from research topic to research topic. At most, it was undertaken by 14 units. Professor Jin Zengsun from Jilin University was the subject of the topic. During this period, the assessment was carried out every year, and the implementation of the excavation was not carried out. If you did not do well, please come in and make the diamond film research in China develop rapidly. The research content and research level have been recognized by international counterparts. At that time, the Ministry of Science and Technology and the 863 expert group gave a high evaluation of the work on the research topic of diamond film, and believed that "the research has characteristics and is in line with the reality of China." During the Ninth Five-Year Plan period, the 863 expert group believed that the industrialization of diamond film should be considered. Therefore, it was undertaken by Jilin University, IOL and Beijing University of Science and Technology. The artificial crystal is responsible for the industrialization of diamond film cutters. Jilin University is responsible for the development of hot cathode methods and thermal applications. Beijing University of Science and Technology is responsible for the development of DC injection methods. During the fifteenth period, Jilin University continued to undertake the 863 project and deepen the applied research in electrical engineering.
During the period of the Seventh Five-Year Plan and the Eighth Five-Year Plan, the following units have undertaken research projects for the 863 Program: Jilin University, Institute of Artificial Crystals, Beijing Institute of Technology, Sichuan University, Beijing University of Science and Technology, Tianjin University of Technology, Zhengzhou Sanmao, Shanghai Jiaotong University, Hefei University of Technology, Zhengzhou University, Beijing Institute of Physics, Chengdu Tool Research Institute, Anhui Plasma Institute, China University of Science and Technology, Changchun Institute of Physics, Mudanjiang Optoelectronics Institute, Xi'an Jiaotong University, etc.

1. Jilin University
Professor Zou Guangtian, then director of the Institute of Atomic and Molecular Physics of Jilin University, formed the Diamond Film Research Group in February 1984. After more than a year of hard work, the research team independently designed and developed the first domestic domestic hot filament CVD diamond in 1986. The film preparation device, after a one-year process experiment with this device, synthesized the first CVD diamond film in China in April 1987, filling the domestic blank. More than 20 doctoral and master students have been trained in this field, and a number of important scientific research achievements have been achieved, many of which have reached the international advanced level.
During the period from the 7th to the 15th, Professor Zou Guangtian of Jilin University, etc., established the electronic enhanced hot wire CVD, DC hot cathode CVD and microwave CVD methods with the support of the National 863 Program, and prepared large-scale high by electron enhanced hot wire CVD. The heat conductive diamond thick film realizes the rapid growth of high quality diamond film by DC hot cathode CVD method, and the large size diamond film with high thermal conductivity, high insulation and high orientation is prepared by microwave CVD method. The problems of metallization, grinding and cutting of the diamond film surface are solved, and the application of the diamond film heat sink in the semiconductor laser diode array is realized. The Si wafer bonding and thinning technology was solved, and the SOD anti-radiation substrate and electronic device using the diamond film were fabricated, and the radiation resistance and high temperature resistance were significantly improved. Professor Li Hongdong of Jilin University is equal to the rapid growth of homoepitaxial CVD diamond single crystals in China at a rate of 50200 μm/h in 2008. It grows large-sized near-colorless transparent single crystal diamond and is used in high-precision cutting tools and In the field of high-power microwave windows, some of the achievements have reached the international advanced level.
In recent years, Jilin University has increased the application research of super-hard precision machining tools, and has made important breakthroughs, and has been practically applied and industrialized. Developed a series of new series of superhard finishing tools such as CVD diamond, PCD diamond and CBN. With Changchun Bafang Diamond Technology Co., Ltd. as the carrier, it has established an application development model integrating production, learning, research and use. Formed a series of four series of super-hard tool products, super hard tools, grinding wheel dressing tools, stone carving tools, diamond needles for marking machines. These tools have been widely used in the fields of automobiles, rail passenger cars, aviation, stone carving, etc., solving a number of technical problems for large and medium-sized enterprises, greatly improving production efficiency and reducing processing costs. In recent years, he has completed several key projects and won several important awards: 1. “Development and Industrialization of Diamond Thick Film Tools” Key Project of Jilin Province Science and Technology Plan, Appraisal of Achievements in 2010; 2. “CVD Diamond Finishing Tools” Project It was jointly awarded by the Ministry of Science and Technology to the Small and Medium Enterprise Innovation Fund Project of the Ministry of Science and Technology, and passed the appraisal in 2011; 3. The “Carbon and Superhard Functional Film Materials” project won the first prize of the “Jilin Province Science and Technology Award” in 2008; The “High Performance Diamond Tools” project won the “Jilin Province Science and Technology Progress Second Prize” in 2010.

Second, Beijing University of Science and Technology
Beijing University of Science and Technology is also one of the earliest units in China to carry out CVD diamond film research. The main person in charge is Professor Lu. The study started in 1988 and began working closely with the Hebei Academy of Sciences in 1991 on DC Arc Plasma Jet equipment and process research. Under the support of the key technical projects of the 863 Plan “Eighth Five-Year Plan”, the 100 kW DC Arc Plasma Jet CVD system was completed at the end of 1995 and passed the expert appraisal organized by the State Science and Technology Commission in early 1996. Under the support of the “95” major project of the 863 Program, an optical grade (transparent) diamond film was first prepared in China at the end of 1997. Under the continuous support of the 863 Program and the pre-research, supporting and natural science fund projects, after more than ten years of hard work, a series of diamond membranes that can be used for scientific research and large-scale Industrial production have been formed. Quality, low cost preparation equipment. The high-power DC Arc Plasma Jet CVD diamond film deposition system developed by the company uses a unique magnetron rotating arc plasma torch (patent patent) and semi-closed gas circulation system, with independent intellectual property rights and Chinese characteristics. The level that has been achieved so far is: deposition area: maximum 120 mm; deposition rate: 10-30 m/h; maximum thickness: 3 mm; Raman half height: 2.6 cm-1 (optical grade); nitrogen content: 1.6 ppm (optical grade) 8-12m transmittance: 70.6% (optical grade, 60x0.6mm window sample); thermal conductivity: 12-20W/cm.K (heat sink and optical grade); Tan: 1.6x10-4 (35GHz) Breaking strength: ≧300MPa; fracture toughness: 6–10 MPam1/2; sand erosion rate: 1.6x10-3mg/g (180 mesh SiC sand, 134m/s); laser damage threshold: 6-7J/cm2 ( YAG pulsed laser), 1.15–2.26MW/cm2 (CO2 continuous laser); oxidation resistance: 800°C, 3 minutes, 8–12m transmittance decreases by less than 3%, applying Y2O3 protective coating can improve short-term use temperature Up to 900 ° C; thermal shock resistance: instantaneous temperature difference of 1300 ° C does not burst. Many important high-tech application requirements have been met.
Beijing University of Science and Technology under the gas cycle conditions, the use of high-power DC Arc Plasma Jet CVD system to prepare large-area optical grade diamond self-supporting film is still the only successful case at home and abroad. The research group has published more than 300 research papers in academic journals at home and abroad, and obtained more than 20 patents. He has won the second prize of Beijing Science and Technology Progress Award and the National Invention Exhibition Gold Award.
In 2009, Hebei Plessman Diamond Technology Co., Ltd. was established in cooperation with the Hebei Academy of Sciences. At present, it has more than 30 sets of 30 kW production DC Arc Plasma Jet CVD system, covering tool grade, heat sink grade and optical grade diamond self-supporting film products. Production capacity exceeds 3 million cubic millimeters per year. Most of the products are sold to Europe and the United States, and domestic sales have gradually increased in recent years. At least 50 sets of DC Arc Plasma Jet CVD systems in China have been operated by more than 10 colleges and universities, research institutes and enterprises, and have become one of the main technologies for CVD diamond film research and industrial production.
In recent years, Beijing University of Science and Technology has made great progress in microwave plasma CVD technology. There have been breakthroughs in the development of microwave cavity simulation and new microwave plasma CVD diamond film deposition equipment. The 8 kW ellipsoidal cavity microwave plasma CVD apparatus and the improved "lower coupled tunable resonant cavity" microwave plasma CVD apparatus have been successfully developed, which has significantly reduced the huge gap between China and foreign countries in this field.
Based on Beijing University of Science and Technology and Hebei Presman Diamond Technology Co., Ltd., Beijing R&D Center (Beijing Plessman Diamond Technology Development Co., Ltd.) has been established to accelerate the development of high-end diamond film applications.

Third, Beijing Institute of Artificial Crystals
The research on diamond film of Beijing Institute of Artificial Crystals began in 1987. After the National High-Tech Plan (863 Program) was listed in the second half of the same year, it was the state during the “July 5th - 9th Five-Year Plan” from 1987 to 2000. One of the main commitment units of the study in the 863" program.
Under the guidance and support of the national “863” plan, it undertook the research on the key technology project “Diamond Film Tool Application” in the new material field of the plan and the key project “New Technology of Diamond Film Industrialization for Tools” in the new material field. According to the development trend of international CVD diamond technology and application, and the specific conditions of China's technology and market, as well as the specific division of labor, the Beijing Institute of Artificial Crystals mainly conducts research on the key technologies of industrialization of hot wire CVD diamond tools. The industrialization growth technology, processing technology and application research and market development of diamond film tool products have achieved success.
The transformation of project results and the industrialization of diamond film tools have also made great progress. In 1996, it established a joint venture with Nanjing Tiandi Group to establish Beijing Tiandi Oriental Diamond Technology Co., Ltd. (now renamed Beijing Tiandi Superhard Materials Co., Ltd.), and initially constructed the industrialization mode of diamond film. The company is the first joint-stock enterprise in China that focuses on diamond film technology and applied research and development. It has realized the transformation from laboratory technology to production technology, and established a production line from the growth and processing of diamond thick film materials to diamond thick film tool products. Formed a product market to develop a variety of dozens of specifications and varieties of tools and product technology, and formed a scale.
In 1998, the company and the Shanghai Institute of Acoustics of Tongji University jointly undertook the National Natural Science Foundation's "Laser Ultrasonic Study of Diamond Film Acoustic Characteristics" project and cooperated with the University of Heidelberg, Germany, to successfully determine the longitudinal sound velocity and surface acoustic wave of diamond thick film by laser ultrasonic technology. Speed, laid the foundation for the very high frequency surface acoustic wave technology and devices used in the fifteenth and eleventh military applications.
The research results of the crystal film of the crystal hospital have been commended by the state for many times. In 1998, it was awarded the second prize of the National Science and Technology Progress Award by the Ministry of Science and Technology (the award-winning project: “Development of Diamond Film for Tools and Its Application Development”, and the Ministry of Building Materials Bureau issued in 1997. First Prize of Science and Technology Progress Award (winning project: “Diamond Film Preparation and Tool Heat Sink Application”). Diamond tool products have also applied for 4 national patents.
For many years, it has developed a practical high-speed, large-area hot wire method CVD diamond thick film growth technology and equipment and has the ability to industrialize. The unique technical specifications of the straight wire structure, growth area, growth rate, growth quality and other technical and economic indicators such as low production cost of equipment and diaphragm have reached the international advanced level of the technology. At the same time, the key processing technology of CVD diamond film material was researched and developed, and the laser cutting of diamond thick film, high precision, high gloss polishing and vacuum welding and other technologies were completed, which laid a foundation for the application development of tool products.
Beijing Tiandi Superhard Materials Co., Ltd., controlled by the Artificial Crystal Research Institute, has completed research and market development of various diamond film tool products for many years. Developed product technology for five diamond-like membrane tools, including diamond film cutters, diamond film drawing die tools, diamond film wheel dressing tools, diamond film wear parts, and diamond film optical processing tools. Diamond film tools have been widely used in a variety of industrial and high-tech processing of modern materials. They include: non-ferrous metals, aluminum-based lightweight high-strength composites, composite carbon fiber materials, reinforced composite wood materials, most wire materials including steel, and treatments including nano- and micro-powders. In the automotive industry, motor industry, aerospace industry, bearing industry, machine tool industry, electronic information industry, home appliance industry, film manufacturing, food industry, gold and silver jewelry industry, metal wire and wire mesh industry, milling industry food industry, wood and indoor The decoration industry and other civil and military industrial sectors of the national economy have been applied. Some tool application development is at the international advanced level. At present, this technology has become one of the main economic pillars of the company.

Fourth, Shanghai Jiaotong University
As early as 1987, Shanghai Jiaotong University began to work on low-pressure gas-phase synthetic diamond film. Professor Zhang Zhiming and others established a diamond film coating research base earlier in China, and successively assumed the “seventh five-year plan” and “eight five-year plan”. Research work on CVD diamond film in the new material field of the National 863 Program during the Ninth Five-Year Plan and the Tenth Five-Year Plan period. From 1996 to 2000, the 863 project "CVD Diamond Coating Technology" and the Shanghai Science and Technology Commission Development Fund Project "Application of CVD Diamond Coated Tools in the Automotive Industry" and "Development and Development of Diamond Coating Drawing Dies" have been completed. "A number of scientific research projects." The diamond-coated wire drawing die was prepared by the direct-pull perforated hot-wire CVD method at home and abroad. The quality is stable. The test of drawing the electrode in the actual production line shows that the life of the wire drawing die can be increased by 5-10 times.
Since 2002, Shanghai Jiaotong University has undertaken the National 863 Major Project and the Shanghai Science and Technology Commission Nano-Special Project “Application and Industrialization of Nano-Diamond Composite Coatings”, and first applied the chemical vapor deposition CVD diamond film preparation technology to the international drawing. The mold has realized industrial production. The products have been applied in more than 500 production enterprises, bringing significant economic benefits to the application enterprises. The company has established the first enterprise standard for diamond coating products in China, among which “nano-diamond composite coating” The development and application of layer technology won the second prize of the 2007 Shanghai Science and Technology Progress Award. The “Preparation Method for Large-Aperture Diamond Coating Drawing Die” won the Excellence Award in the 10th China Patent Award in 2007 and the first prize in the invention patent of the 4th Shanghai Invention and Creation Patent Award in 2006.
Shanghai Jiaotong University has also made breakthroughs in the pretreatment of complex matrix surfaces and CVD coating technology, and developed a practical chemical mechanical composite surface pretreatment technology suitable for complex shape tool substrates, which is suitable for cemented carbide complexes. Shape tool base CVD coating device, etc., related research and achievements have been rated as the National Natural Science Foundation of China outstanding project, hosted by the National 863 Program key project sub-project "Diamond coating complex tool preparation and its efficient processing in composite materials "Application", Shanghai Science and Technology Innovation Action Plan nano-specialized "development and application of complex shape nano-diamond film coating tools", national small and medium-sized enterprise innovation fund "ceramic-based diamond composite coating tools" and other related scientific research projects, and Successfully passed the acceptance, the technical research project of the Shanghai Science and Technology Innovation Action Plan, the “Technical Standards for Diamond Film Coating Products” project has passed the acceptance and obtained the industry standard project of the Ministry of Industry and Information Technology.
Shanghai Jiaotong University also established Shanghai Dating Diamond Coating Co., Ltd., which is dedicated to the industrialization of CVD diamond coating products. It has formed a complete set of technology research and development system from equipment manufacturing to product development. At present, the company can meet various chemical chemistry. Vapor deposition synthetic diamond coating product development needs.

V. Shanghai University
In the 1980s, under the leadership of Professor Xia Yiben, Shanghai University (formerly Shanghai University of Science and Technology) began to grow diamond films by chemical vapor deposition (CVD). In 1995, under the auspices of the National Natural Science Foundation of China and Shanghai, the diamond film was first successfully deposited on an alumina ceramic substrate, and the composite material was used for high-frequency, high-power density integrated circuit package substrates. The key project of “Preparation and Application of Large Area Diamond Films” was approved by the Shanghai Science and Technology Commission in 1996. The key project of “Selective Directional Growth of Diamond Films” was identified in 2001 by the Shanghai Municipal Education Commission. At the end of 2002, the international cooperation project-Shanghai Applied Materials Research and Development (AM) Fund Project “Diamond Film/Alumina Ceramic Composite Substrate Materials Adapted to Very Large Scale Integrated Circuits” was completed. The result of “Diamond Film/Alumina Ceramic Composite Substrate Materials Adapted to Ultra-High Speed ​​and High Power Integrated Circuits” won the third prize of the 2003 Shanghai Science and Technology Progress Award.
Since 2001, with the support of the National Natural Science Foundation of China and the Shanghai Municipal Science and Technology Commission, the application of diamond films in high-energy particle (ray) radiation detectors has been pioneered in China. The Shanghai Science and Technology Research Project “Research on Diamond Film Particle Detector” was approved by the Shanghai Science and Technology Commission in 2003. The National Natural Science Foundation project "Development of High-Resolution X-Ray Imaging - Micro-Gas Chambers" was completed in 2003. This work first reported the use of diamond film/silicon composites as substrates for micro-gas chambers (MSGC). Effectively overcome the problem of charge accumulation in conventional substrates. In 2004, under the auspices of the International Cooperation Project (AM) Fund, the design study of the integrated electronic system of the diamond film particle detector chip 1128 was carried out. At the end of 2005, the National Natural Science Foundation of China completed the “High-speed, strong anti-irradiation particle detector research”, successfully developed the Au/[001] diamond film/silicon/Al unit detector, and the CrAu composite electrode strip width and spacing. For the 25μm 1×128 microstrip detector, the fund committee experts rated the project as “excellent”.
At the end of 2008, the National Natural Science Foundation project “Design and Process Research of Diamond Thin Film Ultraviolet Detectors” was completed. By improving the quality of the diamond film and improving the device structure, the use of the coplanar gate structure significantly improved the UV detection sensitivity and UV/visible resolution. . Since 2009, he has been funded by the National Natural Science Foundation of China to conduct research on diamond-based field-effect phototransistors (OP-FETs). In 2011 and 2012, the National Natural Science Foundation of China was continuously supported by the development of diamond film under strong magnetic field and the preparation of boron (10B)/diamond film composite structure and neutron array detection technology.
In October 2000, Shanghai University held the 2000 International Conference on Diamond Materials and Electronic Devices in the Asia-Pacific Region. Professor Xia Yiben served as the chairman of the conference. On December 27-29, 2010 and June 18-20, 2012, Shanghai University successfully held two Sino-Russian bilateral seminars on “CVD Diamond Trends and Challenges” to promote exchanges between China and Russia in this field. Promoted the development of domestic CVD diamond research.

Sixth, CVD diamond production enterprises
After nearly 10 years of development, the domestic diamond has made great achievements in the preparation, application and industrialization. It has experienced the development from scratch, from small to large, and has a very broad market demand and development space. The main manufacturers are Beijing Xiboer Technology Development Co., Ltd., Beijing Tiandi Oriental Superhard Materials Co., Ltd., Hebei Presman Diamond Technology Co., Ltd., Shenzhen Leidi Technology Co., Ltd., Shanghai Dating Diamond Coating Co., Ltd., Changchun Bafang Diamond Technology Co., Ltd. etc. (This article is excerpted from "China's Superhard Materials Industry Fifty Years")

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