Two stage epitaxial growth of wafer-size multilayer h-BN by metal-organic vapor phase epitaxy – a homoepitaxial approach. (12th November 2020)

• Record Type: Journal Article
• Authors: Dąbrowska, Aleksandra Krystyna; Tokarczyk, Mateusz; Kowalski, Grzegorz; Binder, Johannes; Bożek, Rafał; Borysiuk, Jolanta; Stępniewski, Roman; Wysmołek, Andrzej
• Is Part Of: 2D materials. Volume 8:Number 1(2021)
• Publication Date: 2020-11-12
• Subjects: h-BN -- r-BN -- MOVPE -- XRD -- homoepitaxy -- growth; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/abbd1f
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Van der Waals heterostructures based on hexagonal boron nitride (h-BN) and other 2D materials may pave the way for future electronic applications. Wafer-scale uniform h-BN substrates are a must in this respect. In this work, we demonstrate a new growth regime which allows for scalable, uniform synthesis of high quality h-BN layers on 2' sapphire substrates. We propose a new approach to metal organic vapour phase epitaxy of h-BN layers on sapphire substrates. The growth scheme involves an intermediary BN buffer layer grown under self-limiting conditions (continuous flow) followed by the final growth of h-BN with flow modulated epitaxy in one growth run. This scheme can be regarded as homoepitaxial growth of h-BN on a self-limiting buffer. Our studies show that the buffer layer allows to control the nucleation at the crucial early stages of BN layer growth, suppressing unwanted out-of-plane growth. It can also be used to control the density of point-like defects responsible for unwanted luminescence from the h-BN layer. Moreover, our results show that the buffer effectively suppresses the creation of amorphous BN at the sapphire/h-BN interface.