导　读

Since 2000, Peng Lianmao led the team to carry out carbon nanotube electronics research, which has gone through 21 spring and autumn。Lack of funds, project bottlenecks, short-term revenue difficulties...During this period, many teams at home and abroad gave up their research in this field for various reasons。"Only with faith in your heart can you persist to this day.。Facts have proved that our insistence is right, and we have achieved a breakthrough from 0 to 1, developed a complete set of independent carbon chip technology from scratch, and laid a good foundation for the development of the subsequent autonomous and controllable carbon-based integrated circuit industry。Recently, Peng Lianmao, academician of the Chinese Academy of Sciences and director of the Carbon-based Electronics Research Center at Peking University, said。

Academician Peng Lianmao

"Carbon-based chips will become the best choice for smart city operation and development"

The development of carbon chip technology has a wide and far-reaching impact on people's lives。Peng Lianmao said that in the short term, the arrival of 5G technology will make the city become a "smart city", the deep integration of information, industrialization and urbanization, the clothes, food, housing and transportation of citizens will change greatly, and the happiness index will also rise。"Smart city" can not be separated from massive data computing, and it needs to be supported by chips with powerful processing power。Behind the "smart city" is an electronic high-speed channel network composed of chips with faster processing speed, smaller volume, lower power consumption and better performance。The 6G technology after 5G will have higher requirements for chips, and carbon-based chips will undoubtedly become the best choice to support the development of smart cities based on these technologies。

Healthcare, wearable electronics, iot and biocompatible devices...Carbon-based integrated circuits can also be widely used in the above fields。彭练矛举例说，在医学领域，可以充分利用碳基材料能弯曲、折叠、扭曲、压缩、拉伸甚至变成任意形状的特点，制作成柔性电子检测传感器。The sensitivity of this sensor is very high, and it can make early diagnosis of cancer, cardiovascular diseases, genetic diseases and infectious diseases。It is worth noting that the carbon-based flexible sensor is low-cost and easy to promote, small and portable, anti-irradiation and fearless of dangerous environment, which will have an important impact on improving the patient's medical experience, improving the efficiency of medical treatment, and reducing the pressure of doctors。

The research and development of carbon chip technology is a systematic engineering, which needs to be considered in all aspects, from materials, equipment to computer-aided design tools。Peng Lianmao thinks，Carbon chip technology can be developed by drawing on the experience of many silicon-based technology developments，The focus is on the preparation of carbon-based materials，Special requirements and processes for the preparation of carbon-based transistors，The compatibility of carbon chips on flexible and transparent substrates and the ultra-high frequency characteristics bring new application scenarios，Carbon chip cryogenic process can provide unique 3D monolithic chip design required computer aided tools。

Return to Peking University to join the ranks of nano-electronic "dreamers"

After graduating from the Department of Radio Electronics of Peking University in 1982, Peng studied and worked in the United States and the United Kingdom for more than 10 years, mainly engaged in the field of electron microscopy。At the end of 1994, Peng Lianmao returned to China, and he wanted to make a career in China。"At first I just carried on with my previous research, but at the turn of the century, the opportunity presented itself。Peng Lianmao recalled that on the one hand, the rise of nanotechnology in full swing in the world has greatly promoted the enthusiasm of scientific researchers for the research of nano functional materials with special properties, and an outstanding representative of these materials is carbon nanotube materials。On the other hand, in 2005, the International Semiconductor Technology Roadmap Committee clearly stated that traditional silicon-based CMOS technologies would reach their performance limits around 2020。In the face of the difficulties encountered by silicon-based chip technology, the application of carbon nanotube materials with extremely excellent properties to the chip technology of the post-Moore era has become the dream of countless scientific researchers around the world。

In April 1999, Peng Lianmao returned to Peking University and joined the ranks of nano-electronic "dreamers"。For the next six years, his research team has largely followed the international frontier。"In 2007, our team made the first important breakthrough - the preparation of the world's first CMOS device performance beyond the performance of silicon-based devices - N-type carbon tube transistor。"Peng Lianmao said。By solving this world problem, Peng Lianmao's team has officially entered the international stage of carbon-based chip research as the protagonist。

In 2005, Intel's Advanced Devices Research group published an article stating that they found that conventional semiconductor doping processes could not produce carbon nanotube devices that could outperform silicon-based CMOS。In 2006, Intel publicly announced that it was abandoning the carbon nanotube solution。Peng Lianmao told reporters that because of the understanding that the use of traditional doping methods can not be prepared beyond the silicon-based technology of integrated circuits, his team began to explore undoped technology very early。In 2007, the team made a breakthrough in the undoped preparation of carbon nanotube CMOS integrated circuits, and in 2017, the size of carbon-based devices was reduced to the level of 5 nanometers, and the device performance was close to the theoretical limit, and the comprehensive index exceeded more than ten times that of silicon-based devices。By 2020，The team has made another important breakthrough in the research process of materials for large-scale high-performance carbon nanotubes integrated circuits，For the first time, the purity and density required for carbon nanotube arrays for large-scale carbon-based integrated circuits have been achieved，And the use of this material to achieve the first performance beyond silicon based integrated circuits，The frequency of the circuit exceeds 8GHz，This is dozens of times higher than the previous best in the world, 280MHz, created by the IBM team in 2017。

"After 15 years, carbon chip technology is expected to become the mainstream chip technology"

"In the laboratory, we and our colleagues in the United States have demonstrated that carbon nanotube transistors have a ten-fold advantage over the most advanced silicon-based transistors。In addition, the three-dimensional chip framework that can be built based on carbon nanotube transistor technology can improve chip performance by hundreds or thousands of times。Peng Lianmao said that although the integration of the most complex carbon nanotube chips is only tens of thousands of transistors, it is a world away from the tens of billions of transistors of advanced silicon-based chips。However, carbon nanotube technology can provide chip performance that is far from possible in silicon-based chips。Compared with silicon-based semiconductor technology, the current integration maturity of carbon-based technology is not enough, and the country needs to vigorously promote it。

谈及碳芯片技术的产业化，彭练矛表示，首先需要投入资金和时间，没有类似硅基集成电路千亿元量级的投入和10-15年的研发时间，碳芯片技术是不可能成熟的。Under these preconditions，The industrialization of carbon chips should take the lead in some areas where traditional semiconductor technology is not well suited，Examples include high-performance thin films and sensing electronics that are essential for the future of the Internet,Including flexible wearable electronics and other fields;The second is the submillimeter wave and even terahertz electronic technology that is currently out of reach of traditional semiconductor technology，In particular, the integrated circuit technology required for future 6G technology that can be used in bands above 90GHz。

"The biggest challenge facing China's development of carbon chips is not from technology, but the most fundamental judgment: silicon-based semiconductor technology can go on and dominate chip technology for decades, and in the process, China successfully counterattack to obtain silicon-based chip technology dominance.。But this may not be the case with the future development of chip technology。"Peng Lianmao thinks，In the case of national attention and sufficient funding for scientific research，It is expected that carbon-based technology can be used on a small scale in some special fields in 3-5 years;It is expected in the next 10-15 years，Silicon-carbon fusion technology will become mainstream;It is expected that in 15 years, carbon-based chips are expected to take advantage of their high performance, low power consumption and diversity，With the change of products gradually become the mainstream chip technology。"We believe in the science and believe that since the science has shown that the ceiling of carbon-based chips is much higher than that of silicon-based technologies, the corresponding hundreds or thousands of times increase in chip performance is enough to support future information technology development for decades.。Even in the face of great difficulties, it is worth persisting。”

Information source: Tencent Network, Academician Hu Xiang

Editor: Provincial Science and Technology Affairs Center

Review: Provincial Science and Technology Department office