A peeling approach for integrated manufacturing of large mono-layer h-BN crystals

TL;DR

This paper presents a scalable chemical vapor deposition method for producing large mono-layer h-BN crystals and a peeling technique for clean transfer, enabling precise assembly of 2D heterostructures.

Contribution

It introduces a novel integrated manufacturing process combining large-area growth and transfer of mono-layer h-BN for 2D device applications.

Findings

Large mono-layer h-BN crystals (>0.5 mm) achieved from platinum foils.

A clean, delamination-based transfer process for h-BN layers.

Sequential assembly of graphene/h-BN heterostructures with atomic precision.

Abstract

Hexagonal boron nitride (h-BN) is the only known material aside from graphite with a structure composed of simple, stable, non-corrugated atomically thin layers. While historically used as lubricant in powder form, h-BN layers have become particularly attractive as an ultimately thin insulator. Practically all emerging electronic and photonic device concepts rely on h-BN exfoliated from small bulk crystallites, which limits device dimensions and process scalability. Here, we address this integration challenge for mono-layer h-BN via a chemical vapour deposition process that enables crystal sizes exceeding 0.5 mm starting from commercial, reusable platinum foils, and in unison allows a delamination process for easy and clean layer transfer. We demonstrate sequential pick-up for the assembly of graphene/h-BN heterostructures with atomic layer precision, while minimizing interfacial contamination. Our process development builds on a systematic understanding of the underlying mechanisms. The approach can be readily combined with other layered materials and opens a scalable route to h-BN layer integration and reliable 2D material device layer stacks.