Full-film dry transfer of MBE-grown van der Waals materials

TL;DR

This paper introduces a polymer-assisted dry transfer method for MBE-grown 2D van der Waals materials, enabling their full-film transfer without degrading properties, thus facilitating heterogeneous integration.

Contribution

It presents a novel dry transfer technique for MBE-grown 2D vdW materials, including air-sensitive magnets, improving integration possibilities.

Findings

Successful full-film transfer of various MBE-grown 2D materials

Transfer does not degrade magnetic properties of 2D magnets

Enables heterogeneous integration of MBE-grown 2D materials

Abstract

Molecular beam epitaxy (MBE) has been used to create high-quality, large-scale two-dimensional van der Waals (2D vdW) materials. However, due to the strong adhesion between the substrate and deposited materials, the peel-off and dry transfer of MBE-grown vdW films onto other substrates has been challenging. This limits the study and use of MBE films for heterogeneous integration including stacked and twisted heterostructures. In this work, we develop a polymer-assisted dry transfer method and successfully perform full-film transfer of various MBE-grown 2D vdW materials including transition metal dichalcogenides (TMD), topological insulators (TI) and 2D magnets. In particular, we transfer air-sensitive 2D magnets, characterize their magnetic properties, and compare them with as-grown materials. The results show that the transfer technique does not degrade the magnetic properties, with the Curie temperature and hysteresis loops exhibiting similar behaviors after the transfer. Our results enable further development of heterogeneous integration of 2D vdW materials based on MBE growth.