Semimetals offer new possibilities for electronic devices

Dr. Yuxuan Cosmi Lin, assistant professor in the Department of Materials Science and Engineering at Texas A&M University, and a team of researchers are studying the potential applications and unique physical properties of semimetals in electronic devices.

This study was published in Nature Reviews Electrical Engineering.

Traditionally, microelectronics and electronic materials can be made of three types of materials: semiconductors for computing, metals for power and signal transduction, and insulators to isolate different electrical components.

A fourth type of material, semimetals, may be a better alternative than the industry standard. Semimetals are a special type of material with properties that fall between those of metals and semiconductors. These materials are important because of their favorable properties, such as widely tunable electronic energy states, electrical conductivity, and their unique topological properties, which help control the flow of electronic devices like transistors and microchips.

Semimetals are essential components of modern microchip technologies, and semimetal-based device technologies can deliver exceptional computing performance and orders of magnitude reductions in power consumption.

In his review article, Lin summarizes and analyzes the potential applications of semimetals in electronic devices, providing researchers with a comprehensive knowledge resource that guides future research and fosters interdisciplinary collaboration.

“This review summarizes all the research conducted so far on semimetals. We redefined the concept of semimetals from the definition, classified them, and summarized their applications in electronics according to the classification,” Lin said. “The review article provides a solid foundation and direction for all further research on semimetals.”

Lin said these metals can be used in new devices such as transistors, nonvolatile memories (memories that can retain energy even when the power is off), and on-chip interconnects made with semimetals and their interfaces with other materials.

It also addresses current issues related to semimetals, such as determining how to evolve processing technologies and converge this technology with traditional silicon technologies, while detailing the challenges in finding new semimetals with desired properties at high throughput.

“This study helps identify current challenges, suggests potential solutions, serves as an educational resource and industry reference, lays a solid foundation for further exploration of semi-metallic technologies, and promotes the development and commercialization of new products,” Lin said.

Enzi Zhai, a graduate student in materials science and engineering, led the work on this review paper. The project was an interuniversity effort with Dr. Cong Su’s group at Yale University and Dr. Qiming Shao’s group at the Hong Kong University of Science and Technology. The three groups have a long history of collaboration and each has contributed significantly to different aspects of semimetallic electronics.

“This is a great opportunity for us, as well as the entire scientific community, to look at problems from a broader perspective and try to better shape future research areas and technology development goals,” Lin said.

“It not only provides a centralized source of knowledge for researchers, but also introduces a new materials option for those who do not study semimetals but work on electronic devices while summarizing the directions of fundamental research on semimetals for their applications in electronics.”