Metallic films of alternating Al and Sb layers are laser pulse irradiated at room temperature in air in order to obtain the semiconducting compound AlSb. Using transmission electron microscopy and high resolution electron diffraction, the crystal growth is studied as a function of the spatial distribution of the laser beam. It is shown that by monitoring the beam inhomogeneities in an easy manner, it is possible to control the crystallite’s size, which may be 50 times the total thickness of the film. The possibility of a self-epitaxy without substrate is also demonstrated.