Van der Waals integration of 2D atomic crystals for advanced multifunctional devices

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2019,（15）
• 页码范围: 1033-1035
• 页数: 3页
• 语种: 英文

摘要

Semiconductor heterostructures play a key role in the development of solid-state electronic and optoelectronic devices.They are generally realized via traditional epitaxial integration,namely two or more dissimilar materials,with matching crystal lattice,polarity and thermal expansion coefficients,are grown on the surface of each other.in recent years,along with the booming development of two-dimensional (2D) atomic crystals,an entirely new integration mode-van der Waals integration-has captured the world's attention (Fig.1a).Its basic principle is straightforward:different isolated 2D crystals are vertically stacked and adhered together by weak van der Waals forces.Such reassembled products are generally referred to as van der Waals heterostructures (vdWHs).Compared with traditional integration,the advantage of van der Waals integration is its arbitrariness,namely any 2D atomic crystals can be integrated layer-by-layer in a desired stacking order,sample thickness,relative angles,and so forth.This considerable operating controllability,coupled with the rich variety of 2D layered materials,offers a versatile material platform to probe new physics and device functionality.Moreover,the dangling-bondfree surface and strong in-plane covalent bond of 2D layers can effectively prevent atomic inter-diffusion at the hetero-interface,which is an undesirable process that degenerates the quality and working life of heterostructure devices.