Sanxiang Metropolitan Daily New Hunan Client Correspondent Zhang Chenlian All-media reporter Yang Sihan Huang Jing
The surface modified diamond particles are filled into the metal mold, and then the mold and the copper are placed in the true air pressure impregnation furnace, the furnace is pumped into a vacuum and heated to about 1,000 degrees, and then the molten copper liquid is poured into the composite blank... After about 5 hours from powder filling to furnace, a diamond/copper composite product with excellent heat dissipation performance was successfully prepared.
This is a high thermal conductivity diamond/copper heat dissipation product independently developed by the student innovation and entrepreneurship team of Hunan Industrial Vocational and Technical College "High conductivity "core" material - opening a new era of chip heat dissipation" to improve the production process. The advent of this technology product provides a strong basic material support for breaking the foreign technology blockade, promoting the progress of mainland high-power chip packaging technology, and upgrading the mainland's third-generation semiconductor chip application system. The team won the first prize in the creative group of the vocational education track in the 9th Hunan Province "Internet +" College Students Innovation and Entrepreneurship Competition.
"Post-00" youth, self-built team, to tackle the pain points of China's chip heat dissipation materials
"The design and manufacture of chips is known as the 'crown jewel of human industry', which is one of the core foundations and key technologies of the electronic information industry, and an important embodiment of national scientific and technological strength and international competitiveness." The electronic products we use every day, such as mobile phones, computers, etc., the operation of these products is inseparable from the chip, which is the soul of electronic products. With the rapid development of the third-generation semiconductor chip technology, the development trend of high integration and miniaturization of chips is obvious, and the heat dissipation requirements of chips are getting higher and higher. The production technology of chip thermal management materials circulating in the market is monopolized by foreign countries and cannot be produced and applied on a large scale. In 2021, after learning about the current situation of China's chip heat dissipation materials "stuck neck" from the "Engineering Materials and Heat Treatment" class, Yang Wangwang, a welding student in the school, he had the idea of independently developing domestic chip heat dissipation materials, and he found Dr. Xiao Jing, a teacher majoring in materials science and engineering in the school, as a mentor, and began to form a team.
"The development of chip cooling products involves multiple fields and disciplines, and our team members come from different majors such as welding automation and industrial Internet." Yang Zhan said that as soon as the information about the team's recruitment was sent, many people signed up, and finally 15 students were selected to join it.
In October 2021, in classroom 7509, the high-conductor "core" material innovation and entrepreneurship team was officially established, at that time, they only had one process equipment, and most of the start-up funds were self-funded. Today, the team has 8 patents related to core technology, the project leader has declared 3 patents as the first inventor, and the team members have won more than 40 national and provincial awards such as the first prize of the National Advanced Mapping Competition in the past three years, and organized 44 innovation and entrepreneurship and science popularization activities.
"At present, the rapid development of artificial intelligence and Internet of Things technology, we post-00s youth, full of love for the motherland, are determined to take the road of becoming talents with skills and serving the country with skills, constantly improve and innovate technology, break the monopoly of technology, and contribute youth power to the field of mainland chip 'stuck neck'." Yang Outlook said.
800 experiments, 1,000 degrees of high temperature, craftsman spirit forge ahead
"This tungsten powder rotates faster, and there are two sides of the diamond that are not plated with tungsten." "This surface, tungsten powder is plated unevenly" ... At the machining center in Wangcheng, Yang and team member Chen Yuefen studied the problem of modification of the surface of often diamonds. One stop is 3 hours, and their goal is to uniformly plate 12 sides of 50-100 micron diamond with tungsten powder with the help of their own diamond surface modification device, thereby reducing the interface thermal resistance and making the diamond and copper better combined.
"Diamond/copper composites are hailed as the next generation of thermal management materials with the most potential. However, diamond is the hardest substance naturally occurring in nature, and how to compound it with copper to reduce the interfacial thermal resistance is the biggest problem we face in the research and development process. At the same time, what kind of method to use to reduce production costs and solve the problem of difficult processing of products is also a problem that the team wants to overcome. Teacher Xiao Jing introduced that after more than 50 enterprises visited and investigated and consulted thousands of literature, the innovation and entrepreneurship team of Gaodai "core" materials finally targeted the research on diamond/copper composite materials.
Now the team needs three core processes to produce diamond/copper composites, while the team only had one process equipment, and they cooperated with Hunan Haoweite to use the company's equipment to complete the other two production processes. The reporter learned that the team members often run between the school company, not only to complete the "mental work" of product design, but also to do the "physical work" of carrying heavy objects, when producing diamond/copper composite materials, they often carry a 10-kilogram crucible to climb to the top of the 4m high furnace, open the lid weighing about 100 pounds, and place the diamond, copper ingots and crucibles together in the furnace, the temperature inside the furnace is as high as 1,000 degrees, the temperature outside the furnace is close to 40 °C, and everyone's thick tooling can wring out sweat, The face is often flushed with heat.
"We have carried out more than 800 experiments, and as soon as the machine is turned on, we have to guard for more than three hours, record the production status of diamond/copper composites at different temperatures and pressure parameters, and often miss the time to eat." Chen Yuefen said that the team is guided by the spirit of craftsmanship and strives for excellence in product development.
Through diamond surface modification process innovation, true air pressure impregnation equipment innovation and mold digital design and manufacturing process innovation, the team successfully improved the thermal conductivity of diamond/copper composites from 700W/m·K to 890W/m·K, and reduced the roughness of the product surface from 1.6 microns to ≤0.8 microns, equivalent to one-fiftieth of the diameter of a hair.
5h per furnace, mass production, domestic heat dissipation materials to help chip upgrade iteration
"In the past, it took 9.5 hours for enterprises to produce a furnace of diamond/copper composite products, but now we can control it at 5h/furnace, shortening the production cycle of high-end chip heat dissipation products by 58%, saving 165 kWh of electricity per furnace and reducing energy consumption by 30%. At the same time, the equipment cost of diamond/copper composite products was reduced from 3 million to 1.9 million. Xiao Jing said that the team has solved the problem that it is difficult to balance the processing accuracy and efficiency of diamond/copper products, and the product accuracy can be controlled at ±0.01 microns, making the large-scale production of diamond/copper composite materials from ideal to reality.
"The chip generates a lot of heat during operation, and if it is not dissipated in time, it will reduce the service life and reliability of the chip. When the chip temperature is above 70°C, the reliability is reduced by 5% for every 1°C increase, and the chip life at 50°C is only 1/6 of 25°C. Our diamond/copper composites have high thermal conductivity and a coefficient of thermal expansion that closely matches that of the chip, which can dissipate heat in time. Yang Zhan said that from chips the size of fingernail shells to chips the size of mobile phones, the products produced by the team can be used.
It is understood that the high-end chip cooling products can be used in data centers, 5G base stations, new energy vehicles and other industries, the team has provided product installation trials for many leading enterprises such as Huawei and Hefei Shengda Electronics, and the performance indicators meet the requirements of use.
"In the past, the performance and computing speed of chips were often limited by the heat dissipation materials of the chip, but now, the domestic chip heat dissipation products developed by the high-conductivity 'core' material innovation and entrepreneurship team will solve the worries of heat dissipation for most chips, which will be conducive to the improvement of China's high-end chip performance and help China's chip upgrade and iteration." Chen Ke, chairman of Hunan Haoweite Company, said.