• Xu, Zai-Quan
• Kalantar-Zadeh, Kourosh
• Bao, Qiaoliang
• Lau, Desmond W. M.
• Kaner, Richard B.
• Zavabeti, Ali
• Russo, Salvy
• Ou, Jian Zhen
• Daeneke, Torben
• Kevehei, Omid
• Carey, Ben
• Gibson, Brant
• Berean, Kyle
• Dickey, Michael
• Clark, Rhiannon

Abstract

A variety of deposition methods for two-dimensional crystals have been demonstrated; however, their wafer-scale deposition remains a challenge. Here we introduce a technique for depositing and patterning of wafer-scale two-dimensional metal chalcogenide compounds by transforming the native interfacial metal oxide layer of low melting point metal precursors (group III and IV) in liquid form. In an oxygen-containing atmosphere, these metals establish an atomically thin oxide layer in a self-limiting reaction. The layer increases the wettability of the liquid metal placed on oxygen-terminated substrates, leaving the thin oxide layer behind. In the case of liquid gallium, the oxide skin attaches exclusively to a substrate and is then sulfurized via a relatively low temperature process. By controlling the surface chemistry of the substrate, we produce large area two-dimensional semiconducting GaS of unit cell thickness (∼1.5 nm). The presented deposition and patterning method offers great commercial potential for wafer-scale processes

Topics

• Deposition
• impedance spectroscopy
• surface
• compound
• Oxygen
• semiconductor
• two-dimensional
• Gallium