Many of today's silicon-based electronic components contain 2D materials such as graphene. Incorporating 2D materials like graphene into these components allows them to be several orders of magnitude smaller than if they were made with conventional, 3D materials. However they are prone to overheating because of the poor heat conductance from 2D materials to the silicon base.
"In the field of nanoelectronics, the poor heat dissipation of 2D materials has been a bottleneck to fully realizing their potential in enabling the manufacture of ever-smaller electronics while maintaining functionality," said Amin Salehi-Khojin, associate professor of mechanical and industrial engineering in UIC's College of Engineering.
One of the reasons 2D materials can't efficiently transfer heat to silicon is that the interactions between the 2D materials and silicon in components like transistors are rather weak.
"Bonds between the 2D materials and the silicon substrate are not very strong, so when heat builds up in the 2D material, it creates hot spots causing overheat and device failure," said Zahra Hemmat, a graduate student in the UIC College of Engineering and co-first author of the paper.
In order to enhance the connection between the 2D material and the silicon base to improve heat conductance away from the 2D material into the silicon, engineers have experimented with adding an additional ultra-thin layer of material on top of the 2D layer -- in effect creating a "nano-sandwich" with the silicon base and ultrathin material as the "bread."
"By adding another 'encapsulating' layer on top of the 2D material, we have been able to double the energy transfer between the 2D material and the silicon base," said Salehi-Khojin.
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