Preparation of Graphene Single Crystal on Boron Nitride Surface Breakthrough
State Institute of Microsystems, Shanghai Institute of Microsystems, State Key Laboratory of Functional Materials for Materials, Tang Shujie and other researchers, through the introduction of gaseous catalyst method, for the first time in the world to achieve high orientation of graphene single crystal hexagonal boron nitride surface rapid growth. On March 11, related research papers were published in Nature - Communication.
The team mastered the nucleation control of graphene and determined the orientation relationship between the single crystal and the substrate. Using acetylene as a carbon source, the team innovatively introduced silane as a catalyst, and prepared the domain size by chemical vapor phase epitaxy. The growth rate of graphene single crystals larger than 20 microns is two orders of magnitude higher than that reported in previous literature. More than 90% of graphene single crystals and boron nitride substrates are strictly oriented, presenting two-dimensional supercrystallization caused by the Moiré fringes. The lattice structure of the prepared graphene has a typical room temperature Hall mobility of more than 20,000 square centimeters per volt-second.
Graphene has excellent electrical properties, excellent thermal conductivity and excellent mechanical properties, but its electrical properties are greatly affected by the substrate, charge impurities and phonon scattering will greatly reduce the electrical properties of graphene. The graphene single crystal grown directly on the surface of hexagonal boron nitride by chemical vapor deposition can avoid interface contamination and damage defects caused by physical transfer, and provide a material basis for further application in the field of integrated circuits. However, due to the lack of catalytic ability of the substrate, the growth of graphene single crystal directly on the surface of the dielectric such as hexagonal boron nitride has been a huge problem.
The research on the gaseous catalytic method proposed in this study has already applied for a patent, which can provide a brand-new idea and technical solution for the preparation of high-quality graphene single crystal films on dielectric substrates.