  The formation of graphene on the SiC(000-1) surface (the C-face of the {0001}
surfaces) has been studied, utilizing both disilane and neon environments. In
both cases, the interface between the graphene and the SiC is found to be
different than for graphene formation in vacuum. A complex low-energy electron
diffraction pattern with rt(43) x rt(43)-R\pm7.6{\deg} symmetry is found to
form at the interface. An interface layer consisting essentially of graphene is
observed, and it is argued that the manner in which this layer covalently bonds
to the underlying SiC produces the rt(43) x rt(43)-R\pm7.6{\deg} structure
[i.e. analogous to the 6rt(3) x 6rt(3)-R30{\deg} "buffer layer" that forms on
the SiC(0001) surface (the Si-face)]. Oxidation of the surface is found to
modify (eliminate) the rt(43) x rt(43)-R\pm7.6{\deg} structure, which is
interpreted in the same manner as the known "decoupling" that occurs for the
Si-face buffer layer.
