Low-temperature fabrication of amorphous carbon films as a universal template for remote epitaxy

Abstract

Recently, remote epitaxy has been explored for the fabrication of freestanding semiconductor membranes and substrate re-use. For remote epitaxy a thin 2D material layer is either manually transferred to a substrate or grown directly on a substrate at high temperature, thus limiting the process scalability or the choice of substrates. Here, we report on the low-temperature deposition (300 °C) of ultrathin sp2-hybridized 2D amorphous carbon layers with roughness ≤0.3 nm on III-V semiconductor substrates by plasma-enhanced chemical vapor deposition as a universal template for remote epitaxy. We present growth and detailed characterization of 2D amorphous carbon layers on various host substrates and their subsequent remote epitaxial overgrowth by solid-source molecular beam epitaxy. We observe that a low-temperature nucleation step is favorable for nucleation of III-V material growth on amorphous carbon coated substrates. Under optimized preparation conditions, we obtain high-quality, single-crystalline GaAs, cubic-AlN, cubic-GaN and $${{\rm{I}}}{{{\rm{n}}}}_{{{\rm{x}}}}{{{\rm{Ga}}}}_{1-{{\rm{x}}}}{{\rm{As}}}$$ layers on GaAs, 3C-SiC and InP carbon-coated (001)-oriented substrates. Our results demonstrate a universal template fabrication process for remote epitaxy. Remote epitaxy is used to grow semiconductor structures on 2D material covered substrates. Here, a method for fabricating ultrathin 2D amorphous carbon layers on III-V semiconductors is demonstrated using plasma-enhanced chemical vapor deposition as a universal template for remote epitaxy.