Selective area epitaxy of GaAs films using patterned graphene on Ge

TL;DR

This paper demonstrates a method for selective GaAs film growth on Ge substrates using patterned graphene masks, highlighting the importance of temperature and annealing in achieving high nucleation selectivity over micron-scale regions.

Contribution

It introduces a novel selective area epitaxy technique employing patterned graphene masks on Ge, with insights into growth conditions affecting selectivity.

Findings

Selective GaAs growth on Ge using patterned graphene masks.

Growth selectivity depends on temperature and annealing time.

High nucleation selectivity achieved over several microns.

Abstract

We demonstrate selective area epitaxy of GaAs films using patterned graphene masks on a Ge (001) substrate. The GaAs selectively grows on exposed regions of the Ge substrate, for graphene spacings as large as 10 microns. The selectivity is highly dependent on the growth temperature and annealing time, which we explain in terms of temperature dependent sticking coefficients and surface diffusion. The high nucleation selectivity over several microns sets constraints on experimental realizations of remote epitaxy.