Ozone based atomic layer deposition of high-K dielectrics for graphene device applications

The initial growth mechanism of Al₂O₃ films deposited by atomic layer deposition (ALD) using trimethylaluminum (TMA) and ozone as a precursor and an oxidant, respectively, on Highly Ordered Pyrolytic graphite (HOPG) has been investigated. Trimethylaluminum (TMA)/water ALD process has been reported to deposit Al₂O₃ along the step edges of HOPG while ozone process induce nucleation sites leading to a conformal deposition on the basal plane and step edges. Here we demonstrate a uniform and conformal Al₂O₃ deposited at 25°C from 6 cycles of (TMA)/ozone as a seed layer toward the integration of high-K dielectrics for top-gated graphene devices. Through this decoration of nucleation sites on graphene due to ozone, we investigate the mechanism of the ozone based process.