  Transfer of graphene, grown by Chemical Vapor Deposition (CVD), to a
substrate of choice, typically involves deposition of a polymeric layer
(typically, poly(methyl methacrylate, PMMA or polydimethylsiloxane, PDMS).
These polymers are quite hard to remove without leaving some residues behind.
Here we study a transfer of graphene with a protective thin oxide layer. The
thin oxide layer is grown by Atomic Deposition Layer (ALD) on the graphene
right after the growth stage on Cu foils. One can further aid the
oxide-graphene transfer by depositing a very thin polymer layer on top of the
composite (much thinner than the usual thickness) following by a more
aggressive polymeric removal methods, thus leaving the graphene intact. We
report on the nucleation growth process of alumina and hafnia films on the
graphene, their resulting strain and on their optical transmission. We suggest
that hafnia is a better oxide to coat the graphene than alumina in terms of
uniformity and defects.
