Zlatan Aksamija, an assistant professor in the Electrical and Computer Engineering Department and the principal investigator in the Nanoelectronics Theory and Simulation Lab (NET Lab), was recently quoted in a Science News story about why scientists are studying how 2-D materials such as graphene behave at high temperatures. In the February 13 edition of Science News, Aksamija said that commonly used silicon-based electronics are “hitting a brick wall” regarding how much smaller they can be manufactured, and that 2-D materials could be ideal for constructing the next generation of tiny devices.
Aksamija’s comments were used to substantiate a Science News article entitled “New technique shows how 2-D thin films take the heat.” The article concluded that figuring out how these thin-film materials react to higher temperatures will determine their use in electronics.
As the article noted, high-energy particle beams can reveal how 2-D thin sheets behave “when the heat is cranked up.” Science News reported that researchers have devised a way to track how these materials, such as the supermaterial graphene, expand or contract as temperatures rise. This technique, described in the Feb. 2 Physical Review Letters, showed that 2-D semiconductors arranged in single-atom-thick sheets expand more like plastics than metals when heated.
“Better understanding the high-temp behaviors of these and other 2-D materials could help engineers design sturdy nano-sized electronics,” observed Science News.
To further support this research, Science News consulted Aksamija, who has become a well-known expert on graphene and other atomic monolayer materials. As Aksamija explains about the subject matter of the Science News article, “Commonly used silicon-based electronics are reaching fundamental limits of how much smaller they can get.” He adds that heat dissipation and removal, in particular, pose challenges at such nanometer scales. However, materials made of ultrathin, 2-D films could be ideal for building the next generation of tinier devices.
Aksamija uses graphene as a good example. “Graphene conducts like a metal but expands more like a plastic,” Aksamija says. “It’s a neat contrast—plastics do not conduct electricity at all! Graphene is weird because it actually shrinks when heated instead of expanding—a possible advantage at interfaces where, for example, molybdenum disulfide would expand and graphene would shrink when heat is dissipated—a good match!”
Aksamija’s 2017 Nanotechnology article, which was included in the journal’s 2017 highlights, continued the research reported by Aksamija and his colleagues on the electronic properties of graphene and molybdenum disulfide grain boundaries, as published on November 29th, 2017, in Scientific Reports.
In general, the NET Lab focuses its research activities in theoretical and computational nanosciences with engineering applications related to emerging semiconductor nanostructures, post-CMOS nanoelectronic devices and computing paradigms, and nanoenergy materials. (March 2018)