Chemical Vapor Deposition of Hexagonal Boron Nitride Films

Chemical vapour deposition (CVD) of hexagonal boron nitride (h-BN) films has emerged as a versatile route to synthesise large-area, atomically thin insulating layers with exceptional thermal stability, chemical inertness and a wide band gap. In this process, volatile boron–nitrogen precursors, most often borazine or ammonia–borane mixtures, are introduced into a heated reaction chamber where they decompose on catalytic or inert substrates to form h-BN domains. Growth parameters such as substrate composition, temperature, precursor partial pressure and gas flow rates are finely tuned to control nucleation density, layer thickness and crystalline orientation. Advances in catalyst design—ranging from transition metal foils to molten alloys—have enabled the production of uniform monolayer to multilayer films over centimetre scales. Following synthesis, h-BN films may be transferred onto target wafers for integration into electronic and optoelectronic devices. As a dielectric support in graphene transistors, a tunnelling barrier in van der Waals heterostructures or a deep-ultraviolet emitter, CVD-grown h-BN continues to underpin key developments in two-dimensional materials science and device engineering.

Research from Nature Portfolio

Recent studies have demonstrated centimetre-scale synthesis of multilayer h-BN on iron–nickel alloy foils by optimising alloy composition and thermal treatment. This methodology yields films that serve both as insulating substrates and encapsulating layers in graphene field-effect transistors, resulting in reproducible carrier mobilities up to 10 000 cm2 V−1 s−1 at room temperature. Complementary work has assessed the quality of commercially available CVD-grown h-BN, revealing that lattice distortions and defect densities often exceed supplier specifications, leading to higher leakage currents and variability in dielectric performance compared with mechanically exfoliated crystals. These findings have prompted calls for more rigorous quality control and reduction of structural defects to unlock the full potential of CVD h-BN in high-reliability electronic applications.

Chemical Vapor Deposition of Hexagonal Boron Nitride Films publication trend

The graph below shows the total number of articles in chemical vapor deposition of hexagonal boron nitride films across all publications each year (not limited to Nature Index journals).

Technical terms

Chemical vapour deposition (CVD): A thin-film synthesis technique in which gas-phase precursors decompose on a heated substrate to form a solid material.

Hexagonal boron nitride (h-BN): A two-dimensional insulating material with a hexagonal lattice of alternating boron and nitrogen atoms, notable for its wide band gap and high thermal stability.

Nucleation density: The number of initial growth sites per unit area on a substrate, which influences domain size and film continuity.

Catalyst reservoir: Bulk uptake of reactive species within a catalyst material, used to control supply of growth precursors during film deposition.

Van der Waals heterostructure: A layered assembly of different two-dimensional materials held together by van der Waals forces, enabling novel electronic and optoelectronic functionalities.

References

1. Large-area synthesis and transfer of multilayer hexagonal boron nitride for enhanced graphene device arrays. Nature Electronics (2023).
2. On the quality of commercial chemical vapour deposited hexagonal boron nitride. Nature Communications (2024).
3. In Situ Observations during Chemical Vapor Deposition of Hexagonal Boron Nitride on Polycrystalline Copper. Chemistry of Materials (2014).
4. Controlling Catalyst Bulk Reservoir Effects for Monolayer Hexagonal Boron Nitride CVD. Nano Letters (2016).
5. Few-atomic-layered hexagonal boron nitride: CVD growth, characterization, and applications. Materials Today (2017).