The effect of graphite surface condition on the composition of Al2O3 by atomic layer deposition

We present a study of the nucleation of atomic layer deposition of Al2O3 on highly oriented pyrolytic graphite (HOPG) using trimethlyaluminum (TMA) with ozone as the oxidant (TMA/O3). In situ x-ray photoelectron spectroscopy (XPS) is used to study TMA/O3 depositions on HOPG. We examine the dependence of TMA/O3 nucleation on deposition temperature and characterize the morphology and uniformity of deposited films by ex situ atomic force microscopy. The impact of several predeposition surface treatments of the graphite surface condition is discussed, particularly with regard to the presence of adsorbed atmospheric contamination.