Chinese researchers explore possibilities of carbon nanotube-based chips

With silicon-based chips nearing their performance limit, Chinese researchers are making progress in using alternative semiconducting materials to design future generation computer chips.

In May, researchers with the Peking University published their study in the journal Science, reporting on aligned, high-density semiconducting carbon nanotube arrays for high-performance electronics.

The carbon nanotube arrays could be used to fabricate large-scale integrated circuits, with the performance exceeding those of conventional silicon transistors with similar dimensions.

The semiconductor industry has been dependent on Moore's Law to improve performance, but the development of conventional silicon-based chips is slowing down. Scientists and engineers have been trying to find alternative materials that could help sustain the computing power of new devices.

Zhang Zhiyong, one of the researchers, said carbon nanotubes have been considered as promising candidates to replace silicon in making transistors. Researchers around the world, including those from IBM and the Massachusetts Institute of Technology, have been working in the field.

However, attempts to create large-scale integrated circuits using carbon nanotubes have been troubled by fabrication and purity problems, Zhang said, adding that the carbon nanotubes have to be packed densely enough to make good transistors.

"We have developed a method using high-purity carbon nanotubes and lining them up in high density, which helps push carbon-based semiconductor technology from laboratory research to industrial application," Zhang said.

Peng Lianmao, the leading researcher, has been dedicated to building semiconductor devices with carbon nanotubes for more than 20 years. He said carbon nanotubes with the advantages of low cost, low power consumption and high efficiency, can be an ideal material for developing the next generation of transistors.

"Our research on carbon nanotube-based transistors may lead the way for China's chip industry to surge ahead," Peng said.

However, it is not easy for any scientific outcomes to be industrialized, especially for high-performance integrated circuits.

"Our lab in the university is not enough for the development of engineering techniques and industrial chains," Peng said.

In September 2018, the Beijing Institute of Carbon-based Integrated Circuits was established by the Peking University and the Beijing Municipal Science and Technology Commission to foster the research and production of carbon nanotube-based chips.

Government support and company cooperation are indispensable to realize industrial-scale production of carbon nanotube-based chips, Peng said.

"China is investing big in its chip industry, and is willing to embrace new emerging technologies. This creates a favorable environment for the development of carbon nanotube-based chips," Peng said.