Deterministic transfer of two-dimensional materials by all-dry viscoelastic stamping

TL;DR

This paper introduces an all-dry, viscoelastic stamping method for the deterministic transfer of two-dimensional materials, eliminating wet chemistry steps and enabling cleaner, more efficient fabrication of heterostructures.

Contribution

The authors develop a novel dry transfer technique using viscoelastic stamps that improves yield, cleanliness, and suspension capabilities compared to traditional wet methods.

Findings

The method is quick and efficient.

It avoids capillary forces, allowing free suspension of materials.

High transfer yield is achieved.

Abstract

Deterministic transfer of two-dimensional crystals constitutes a crucial step towards the fabrication of heterostructures based on artificial stacking of two-dimensional materials. Moreover, control on the positioning of two-dimensional crystals facilitates their integration in complex devices, which enables the exploration of novel applications and the discovery of new phenomena in these materials. Up to date, deterministic transfer methods rely on the use of sacrificial polymer layers and wet chemistry to some extent. Here, we develop an all-dry transfer method that relies on viscoelastic stamps and does not employ any wet chemistry step. This is found very advantageous to freely suspend these materials as there are no capillary forces involved in the process. Moreover, the whole fabrication process is quick, efficient, clean, and it can be performed with high yield.