Domestic researchers have found a breakthrough in the performance limitations faced by existing semiconductor technology. Instead of using silicon, which faces limitations such as integration density and heat generation, they are utilizing metals capable of high performance as semiconductor devices.
A research team led by Professor Shim Woo-young from Yonsei University has developed a metal material to replace silicon semiconductor devices, as announced on the 20th.
Currently used semiconductor devices are based on silicon. Silicon has an electrical conductivity that is intermediate between conductors and insulators, which is why it is called a semiconductor. Conductors are materials that conduct electricity well, while insulators are materials that do not.
Silicon-based semiconductors have now reached their performance limits, and developing high-performance semiconductors requires new materials. Recently, there have been active attempts to develop "metal transistors" using conductive metals.
The research team created nickel nanosheets with unidirectionally aligned structures using an electro-deposition method. The nickel nanosheets demonstrated electrical anisotropy more than 1,000 times higher than existing metals. Anisotropy refers to the variation in a material's properties depending on the direction.
The research team utilized nickel nanosheets to create semiconductor transistors and confirmed their ability to control current. As a result, by adjusting the direction of the sheets, current control was possible similar to that of semiconductors, with control efficiency more than 10,000 times superior to that of existing silicon-based semiconductors.
The research team also verified that semiconductor switch devices made using nickel nanosheets could perform logical operations differently from existing semiconductors. This result shows that metal materials could replace existing silicon-based semiconductors.
The electro-deposition method utilized in this research is also expected to be applicable in various fields. Unlike the existing semiconductor process of deposition, electro-deposition has the advantage of precisely controlling metal particles in two-dimensional (2D) space.
Professor Shim noted, "It is significant that we confirmed the potential of current switching technology using metal materials," adding, "I expect it will lead to the development of new material technologies based on metals."
The research findings were introduced in the international journal "Nature Synthesis" on Oct. 31 last year.
Reference materials
Nature Synthesis (2024), DOI: https://doi.org/10.1038/s44160-024-00669-4