Leakage Current Reduction in ALD-Al_2O_3 Dielectric Deposited on Si by High Pressure Deuterium Oxide Annealing

摘要

This paper reports an effect of post annealing technique for the deposited dielectric films utilizing high pressure deuterium oxide. Al_2O_3 deposited on Si thermal oxide film by plasma-assisted atomic layer deposition (PA-ALD), which can have the advantage of low temperature process. For reforming qualities of the ALD-Al_2O_3, high pressure deuterium oxide annealing (HPDOA) was carried out at 0.3 MPa for 60 min while keeping at 300°C. The leakage current and the breakdown field of metal-insulator-semiconductor (MIS) diodes with the Al_2O_3 gate dielectrics were improved by the HPDOA treatment. The HPDOA is found to be useful for reforming the Al_2O_3 thin film even if it was deposited by PA-ALD.