  The atomic structure and composition of non-interfacial ITO and ITO-Si
interfaces were studied with Transmission Electron Microscopy (TEM) and X-ray
Photoelectron Spectroscopy (XPS). The films were deposited by DC magnetron
sputtering on mono-crystalline p-type (100) Si wafers. Both as deposited and
heat treated films consisted of crystalline ITO. The ITO/Si interface showed a
more complicated composition. A thin layer of SiO$_x$ was found at the ITO/Si
interface together with In and Sn nanoclusters, as well as highly oxygen
deficient regions, as observed by XPS. High energy electron exposure of this
area crystallized the In nanoclusters and at the same time increased the
SiO$_x$ interface layer thickness.
