Opening of triangular hole in triangular-shaped chemical vapor deposited hexagonal boron nitride crystal

Abstract

In-plane heterostructure of monolayer hexagonal boron nitride (h-BN) and graphene is of great interest for its tunable bandgap and other unique properties. Here, we reveal a H2-induced etching process to introduce triangular hole in triangular-shaped chemical vapor deposited individual h-BN crystal. In this study, we synthesized regular triangular-shaped h-BN crystals with the sizes around 2-10 μm on Cu foil by chemical vapor deposition (CVD). The etching behavior of individual h-BN crystal was investigated by annealing at different temperature in an H2:Ar atmosphere. Annealing at 900 °C, etching of h-BN was observed from crystal edges with no visible etching at the center of individual crystals. While, annealing at a temperature ≥950 °C, highly anisotropic etching was observed, where the etched areas were equilateral triangle-shaped with same orientation as that of original h-BN crystal. The etching process and well-defined triangular hole formation can be significant platform to fabricate planar heterostructure with graphene or other two-dimensional (2D) materials.

Bilayered graphene/h-BN with folded holes as new nanoelectronic materials: modeling of structures and electronic properties

“…4f). Notably, similar triangular holes in the BN-layer with a predominance of the boron atoms at the boundary were observed earlier in the experiments2728.…”

“…The corresponding graphene nanomesh GNM ∇ 1 of the (6; −2; 2; 4) unit cell with triangle holes is metallic with a narrow metallic band near the Fermi level (Fig. 7c), which is in agreement with GNMs with triangle holes28.…”

“…As a result, six atom pairs are connected and form all sp 2 smooth folded hole with radius . The holes in the top BN layer have a triangular shape (the same triangular holes were considered earlier in GNMs2829). The hole in the bottom G layer has the same shape but it is rotated by 180° similarly to Fig.…”

Fundamentals of Chemical Vapor Deposited Graphene and Emerging Applications

“…hBN can be considered as a structural analogue of graphene, which is composed of alternating boron and nitrogen atoms in a honeycomb lattice rather than the carbon atoms. Graphene with a zero bandgap is a semimetallic as discussed in Section 1, while hBN with a bandgap of ~6 eV is insulating [100][101][102][103][104][105][106][107]. Significant carrier mobility of graphene has been achieved on atomically flat hBN as a dielectric layer for the FET device.…”

A high-throughput synthesis of large-sized single-crystal hexagonal boron nitride on a Cu–Ni gradient enclosure

“…1. [5][6][7][9][10][11][12][13][14][15][16][17][18][19][20][21][22] It is in order to grow h-BN with a higher growth rate and simultaneously guarantee the lateral size.…”