The third dimension may be responsible for preventing electronics from becoming thinner, smaller and more flexible, according to international cooperation that has developed a way to produce new, idealized two-dimensional semiconductor materials. They published their approach on June 3 Nano research.
Researchers led by Lin Zhou, an associate professor of chemistry at Shanghai Jiao Tong University in China, focused on indium arsenide (InAs), a narrowband semiconductor with properties useful for high-speed electronics and high-sensitivity infrared photodetectors. Unlike most existing 2D materials with layered structures, the problem, Zhou said, is that InAs typically has a 3D lattice structure, which challenges it to transform into ultra-thin 2D films for advanced electronic and optoelectronic applications.
“The growth of large, ultra-thin 2D non-layered materials is a big challangebut one that is worth solving. Thanks to her high mobility and adjustable bandwidth, 2D InAs can be a critical material for next-generation high-performance nanoelectronics, nano-photonics and quantum devices, “Zhou said.” It has the advantages of both InAs, such as high media mobility, small and direct tape size, as well as ultra-thin 2D materials that are suitable for small devices, are flexible and transparent. “This work also provides a promising way to further expand the group of 2D semiconductors to include materials with non-layered structures.
Researchers have taken advantage of the weak atomic attraction known as the van der Waals force in the growth of epitaxy. Strength describes how neutral molecules can bind to each other, while epitaxy involves applying an overlay of a material to a crystal-like substrate. Using atomically flat mica, which is naturally layered, as a substrate, the researchers grew a thin layer of InAs. The molecules in the mica substrate and the molecules in the InAs are attracted to each other enough to bind together, preventing the growth of InAs in the 3D grid. In addition, van der Waals growth ensures tension-free and improper fitting of dislocations in 2D InAs. InAs can be incredibly thin with the desired properties.
Zhou also noted that InAs and substrate do not bond covalently, so they can be separated and the substrate reused, which makes synthesis process more cost effective.
“We also found that we could adjust the properties of 2D InAs by changing the thickness of the material due to the quantum constraint effect,” Zhou said. “2D InAs is easy to adapt to achieve the desired properties and to integrate with other compounds. In addition to manipulating the thickness during synthesis, we can also align 2D InAs with other 2D materials to form heterojunctions for multifunctional performance, giving them significant advantages in electronics and photovoltaics. “
The final 2D InAs material is in the form of triangular flakes approximately five nanometers thick. This is about 0.0007 the size of a red blood cell. The smaller the material, the smaller the devices it will eventually include, Zhou said.
“Prior to this work, no high-quality 2D – meaning less than 10 nanometers thick – InAs was reported, let alone scalable synthesis of 2D InAs single crystals with unique optical and electronic properties,” Zhou said. “Our work paves the way for miniaturization of InAs-based devices and integrations.”
Zhou then said the team would study a new 2D semiconductor for growth with the ultimate goal of achieving scalable synthesis of high-quality 2D materials over large areas for multifunctional applications.
Jiuxiang Dai et al, Controlled growth of two-dimensional InAs single crystals by Van der Waals epitaxy, Nano research (2022). DOI: 10.1007 / s12274-022-4543-8
Provided by Tsinghua University Press
Quote: Controlled synthesis of crystal flakes paves the way for advanced future electronics (2022, June 17), retrieved on June 18, 2022 from https://phys.org/news/2022-06-synthesis-crystal-flakes-paves-path .html
This document is subject to copyright. Except for any fair transaction for the purpose of private research or study, no part may be reproduced without written permission. The content is provided for informational purposes only.