• Vilasam, Aswani Gopakumar Saraswathy
• Balendhran, Sivacarendran
• Crozier, Kenneth B.
• Gupta, Bikesh
• Javey, Ali
• Li, Li
• Higashitarumizu, Naoki

Abstract

<p>Large-area epitaxial growth of III-V nanowires and thin films on van der Waals substrates is key to developing flexible optoelectronic devices. In our study, large-area InAs nanowires and planar structures are grown on hexagonal boron nitride templates using metal organic chemical vapor deposition method without any catalyst or pre-treatments. The effect of basic growth parameters on nanowire yield and thin film morphology is investigated. Under optimised growth conditions, a high nanowire density of 2.1 × 10⁹ cm⁻² is achieved. A novel growth strategy to achieve uniform InAs thin film on h-BN/SiO₂/Si substrate is introduced. The approach involves controlling the growth process to suppress the nucleation and growth of InAs nanowires, while promoting the radial growth of nano-islands formed on the h-BN surface. A uniform polycrystalline InAs thin film is thus obtained over a large area with a dominant zinc-blende phase. The film exhibits near-band-edge emission at room temperature and a relatively high Hall mobility of 399 cm⁻²/(Vs). This work suggests a promising path for the direct growth of large-area, low-temperature III-V thin films on van der Waals substrates.</p>

Topics

• density
• impedance spectroscopy
• surface
• phase
• mobility
• thin film
• zinc
• nitride
• Boron
• chemical vapor deposition