Views: 1 Author: Site Editor Publish Time: 2022-05-11 Origin: Site
In a discovery that could accelerate research into next-generation electronics and LED devices, a team of scientists at the University of Michigan has developed the first reliable, scalable method to grow monolayers of hexagonal boron nitride (hBN) on graphene. This process produces bulk high-quality hBN through the widely used molecular beam epitaxy process.
A professor of electrical engineering and computer science at the University of Michigan and corresponding author of the study explained that the graphene hBN structure could power LEDs that generate deep ultraviolet light, which is not possible in today's LEDs. Deep UV LEDs can drive smaller size and higher efficiency in a variety of devices, including lasers and air purifiers.
It is reported that hBN is the thinnest insulator in the world, while graphene is the thinnest of a class of materials called semimetals. The material, with its highly malleable electrical properties important for their role in computers and other electronics, combines hBN and graphene into smooth, one-atom-thick layers. In addition to deep-UV LEDs, the graphene-hBN structure could enable quantum computing devices, smaller and more efficient electronics and optoelectronics, and various other applications.
Researchers have tried in the past to synthesize thin hBN layers using methods such as sputtering and chemical vapor deposition, but they have struggled to obtain the uniform, precisely ordered atomic layers needed to properly bond with the graphene layers. "To get a useful structure requires consistent, ordered arrays of hBN atoms that align with the underlying graphene, which was not possible with previous methods. Some hBN can fall neatly, but many regions are disorganized and randomly arranged. ," the scientists explained.
An American scientist added: "We have known the properties of hBN for many years, but in the past, the only way to get the flakes needed for research was to physically exfoliate them from larger boron nitride crystals, which was more complicated and yielded only tiny flakes of material. But now our process can grow atomic-scale flakes of essentially any size, opening up many exciting new research possibilities. "
