  We investigate the hetero-epitaxial growth of thin film deposited on a (001)
substrate via molecular dynamics simulations, using six fcc transition metals
as our modeling systems. By studying the radial distribution function in the
film layers, we demonstrate the importance of the sign of lattice mismatch on
the layer structure. For positive lattice mismatches, the film favors
pseudomorphic growth, whereas for negative mismatches, a sharp transition
happens within the first few monolayers of adatoms and the film layers are
transformed into the close-packed (111) structure. We propose a way to quantify
the compositional percentage of different planar structures in an epilayer, and
demonstrate the strong asymmetric effect between the tensile and compressive
cases of deposition. How temperature affects the asymmetry is also discussed.
