Smooth and conformal Al2O3 Coating on Polystyrene Nanospheres by Using Atomic Layer Deposition

In this study, smooth and pinhole-free Al2O3 films were prepared by atomic layer deposition using alternating exposures of trimethylaluminum and water. The influence of substrate temperature and cycle number on growth rate and surface roughness of Al2O3 films was investigated. X-ray reflectivity curves indicated the growth rate of Al2O3 films was around 1Å/cycle. The smooth and uniform Al2O3 deposition on polystyrene nanosphere shows that atomic layer deposition is an enabling technology to achieve conformal surface coating on nanostructures.