Towards Chirality Control of Graphene Nanoribbons Embedded in Hexagonal Boron Nitride

TL;DR

This paper presents a novel two-step growth method for fabricating sub 5 nm wide zigzag and armchair graphene nanoribbons embedded in hexagonal boron nitride, enabling precise edge control and promising applications in nanoscale circuitry.

Contribution

Developed a two-step growth process to produce edge-specific graphene nanoribbons embedded in hBN with sub 5 nm widths, advancing nanoscale electronic device fabrication.

Findings

Zigzag GNRs show bandgap inversely proportional to width.

Narrow armchair GNRs exhibit fluctuating bandgap widths.

Method enables integration of semiconducting GNRs in insulating hBN substrates.

Abstract

The integrated inplane growth of two dimensional materials with similar lattices, but distinct electrical properties, could provide a promising route to achieve integrated circuitry of atomic thickness. However, fabrication of edge specific GNR in the lattice of hBN still remains an enormous challenge for present approaches. Here we developed a two step growth method and successfully achieved sub 5 nm wide zigzag and armchair GNRs embedded in hBN, respectively. Further transport measurements reveal that the sub 7 nm wide zigzag GNRs exhibit openings of the band gap inversely proportional to their width, while narrow armchair GNRs exhibit some fluctuation in the bandgap width relationship.This integrated lateral growth of edge specific GNRs in hBN brings semiconducting building blocks to atomically thin layer, and will provide a promising route to achieve intricate nanoscale electrical circuits on high quality insulating hBN substrates.