University of Pennsylvania Breakthrough 2D Semiconductor Material Indium Selenide Preparation Process
Researchers from the School of Engineering and Applied Sciences at the University of Pennsylvania in the United States have achieved high-performance two-dimensional semiconductor growth on silicon wafers. The new 2D material indium selenide (InSe) can be deposited at sufficiently low temperatures to integrate with silicon chips.
The report states that many candidate 2D semiconductor materials require such high temperatures to deposit, thereby damaging the underlying silicon chip. Others can be deposited at temperatures compatible with silicon, but their electronic characteristics - energy consumption, speed, accuracy - are lacking. Some meet temperature and performance requirements, but cannot grow to the purity required by industry standard sizes.
Deep Jariwala, Associate Professor of Electrical and Systems Engineering at the University of Pennsylvania, and Seunguk Song, a postdoctoral researcher, led new research. InSe has long shown the potential as a two-dimensional material for advanced computing chips due to its excellent charge carrying capacity. However, it has been proven that producing sufficiently large InSe films is challenging because the chemical properties of indium and selenium often combine in several different molecular ratios, presenting a chemical structure with different proportions of each element, thereby damaging their purity.
The team achieved breakthrough purity using a growth technique called "Vertical Metal Organic Chemical Vapor Deposition" (MOCVD). Previous studies have attempted to introduce equal amounts of indium and selenium simultaneously. However, this method is the root cause of poor chemical structure in materials, resulting in different proportions of each element in the molecules. In contrast, the working principle of MOCVD is to continuously transport indium while introducing selenium in the form of pulses.
In addition to chemical purity, the team is also able to control and arrange the direction of crystals in the material, further improving the quality of semiconductors by providing a seamless electron transfer environment.
Deep Jariwala, Associate Professor of Electrical and Systems Engineering at the University of Pennsylvania, and Seunguk Song, a postdoctoral researcher, led new research. InSe has long shown the potential as a two-dimensional material for advanced computing chips due to its excellent charge carrying capacity. However, it has been proven that producing sufficiently large InSe films is challenging because the chemical properties of indium and selenium often combine in several different molecular ratios, presenting a chemical structure with different proportions of each element, thereby damaging their purity.
The team achieved breakthrough purity using a growth technique called "Vertical Metal Organic Chemical Vapor Deposition" (MOCVD). Previous studies have attempted to introduce equal amounts of indium and selenium simultaneously. However, this method is the root cause of poor chemical structure in materials, resulting in different proportions of each element in the molecules. In contrast, the working principle of MOCVD is to continuously transport indium while introducing selenium in the form of pulses.
In addition to chemical purity, the team is also able to control and arrange the direction of crystals in the material, further improving the quality of semiconductors by providing a seamless electron transfer environment.