  \emph{Wolf-Villain (WV) model} is a simple model used to study \emph{ideal}
molecular beam epitaxy (MBE) growth by using computer simulations. In this
model, an adatom diffuses instantaneously within a finite diffusion length to
maximize its coordination number. We study statistical properties of thin films
grown by this model. The morphology of the WV model is found to be kinetically
rough with a downhill particle diffusion current. In real MBE growth, however,
there are additional factors such as the existence of a potential barrier that
is known as the \emph{Ehrlich-Schwoebel (ES) barrier}. The ES barrier is an
additional barrier for an adatom that diffuses over a step edge from the upper
to a lower terrace which is known to induce an uphill particle current. We
found that with the addition of the ES barrier, the WV-ES model morphology is
rough with \emph{mound formation} on the surface when the barrier is strong
enough. To confirm these results, the correlation function is also studied. We
find no oscillation in the correlation function in the WV model. For the WV-ES
model, the correlation function oscillates. These results confirm that a strong
enough ES barrier can cause mound formation on the WV surface in our study.
