Transferable III-V thin films, combined with light trapping structures, present several interests for photovoltaics: cost, material usage and weight reduction, flexible devices… To obtain such films, remote epitaxy consists in growing above a graphene covered III-V substrate, providing detachable mono-crystals. We report the fabrication of large-area graphene/GaAs substrates by a metal-assisted dry transfer with a high yield (>95%), reduced damage to the lattice, negligible doping, and stress relaxation. After the optimization of chemical etching steps, XPS reveals a residue-free surface with low oxidation levels compared to conventional transfers. Nucleation studies using MBE resulted in the formation of microcrystals, with partial alignment with the underlying GaAs(001).
Graphene assisted III-V layer epitaxy for transferable solar cells
Cattoni, Andrea;
2023-01-01
Abstract
Transferable III-V thin films, combined with light trapping structures, present several interests for photovoltaics: cost, material usage and weight reduction, flexible devices… To obtain such films, remote epitaxy consists in growing above a graphene covered III-V substrate, providing detachable mono-crystals. We report the fabrication of large-area graphene/GaAs substrates by a metal-assisted dry transfer with a high yield (>95%), reduced damage to the lattice, negligible doping, and stress relaxation. After the optimization of chemical etching steps, XPS reveals a residue-free surface with low oxidation levels compared to conventional transfers. Nucleation studies using MBE resulted in the formation of microcrystals, with partial alignment with the underlying GaAs(001).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
