  The development of scalable techniques to make 2D material heterostructures
is a major obstacle that needs to be overcome before these materials can be
implemented in device technologies industrially. Electrodeposition is an
industrially compatible deposition technique that offers unique advantages in
scaling 2D heterostructures. In this work, we demonstrate the electrodeposition
of atomic layers of WS$_2$ over graphene electrodes using a single source
precursor. Using conventional microfabrication techniques, graphene was
patterned to create micro-electrodes where WS$_2$ was site-selectively
deposited to form 2D heterostructures. We used various characterisation
techniques, including atomic force microscopy, transmission electron
microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy to show
that our electrodeposited WS$_2$ layers are highly uniform and can be grown
over graphene at a controllable deposition rate. This technique to selectively
deposit TMDCs over microfabricated graphene electrodes paves the way towards
wafer-scale production of 2D material heterostructures for nanodevice
applications.
