Effects of shadowing in oblique-incidence metal(100) epitaxial growth
  The effects of shadowing in oblique incidence metal (100) epitaxial growth are studied using a simplified model. We find that many of the features observed in Cu(100) growth, including the existence of a transition from anisotropic mounds to ripples perpendicular to the beam, can be explained purely by geometrical effects. We also show that the formation of (111) facets is crucial to the development of ripples at large angles of incidence. A second transition to `rods' with (111) facets oriented parallel to the beam is also found at high deposition angles and film thicknesses. 
Yunsic Shim and Jacques G. Amar