We study the epitaxial growth of thin films formed by the sedimentation of colloidal particles on a microfabricated substrate. The attractive interaction between the colloids, induced by a depletant polymer, leads to the nucleation of islands that grow and coalesce with one another. We use confocal microscopy and particle tracking to study the dynamics of the colloidal particles as they diffuse, aggregate and rearrange configurations during deposition. The saturation island density is estimated as a function of the deposition rate and depletant concentration. We find that our results are in excellent agreement with those obtained from atomic deposition experiments suggesting that our system can be used to model various phenomena that occur in atomic thin film growth. Furthermore, using e-beam lithography we carefully control the underlying substrate morphology to study its effect on the epitaxial growth process. Experiments are in progress to understand nucleation and growth on substrates with different crystalline symmetries including quasicrystals.