Particle-Catalyst-Free Vapor-Liquid-Solid Growth of Millimeter-Scale Crystalline Compound Semiconductors on Nonepitaxial Substrates

ACS Omega. 2020 Apr 15;5(16):9550-9557. doi: 10.1021/acsomega.0c00864. eCollection 2020 Apr 28.

Abstract

Direct growth of single-crystal compound semiconductors on nonepitaxial substrates is a promising route for device processing simplification in electronic and optoelectronic applications. However, the nonepitaxial growth technique for 2D single crystals is still a fundamental challenge. Here, we demonstrate that the macroscopic 2D interface of liquid metals and nonepitaxial solid substrates could be universally designed for the chemical vapor deposition growth of crystalline compound semiconductors. By adopting a sandwiched solid metal/liquid metal/solid substrate environment, millimeter-scale 2D GaS, 2D GaSe, and 1D GaTe single crystals of high quality were synthesized at the interface of liquid gallium and nonepitaxial substrates. Evidence shows that the particle-catalyst-free vapor-liquid-solid growth is driven by screw dislocations. Furthermore, we successfully extend the growth strategy to various metal chalcogenides (Sn, In, Cu, and Ag) and pnictides (Sb). Our work opens up a new route for the direct growth of single-crystalline compound semiconductors on nonepitaxial substrates.