Effect of Hydrogen Partial Pressure on the Reliability Characteristics of Ultrathin Gate Oxide

Abstract

In this letter, we have investigated the reliability characteristics 65Å-thick gate oxide grown in various hydrogen partial pressure. Compared with a dry oxide, device reliability characteristics such as charge-to-breakdown and stress-induced leakage current were improved with increasing hydrogen partial pressure. The electron trapping rate increases with increasing hydrogen partial pressure during the gate oxidation process. However, initial hole trapping rate was reduced for oxide grown in hydrogen and oxygen ambient. In addition, we found that the defect density for large area capacitors was also improved with increasing hydrogen partial pressure. The improvement can be explained by a reduction of strain in the Si–O bond due to the incorporation of hydrogen during the oxidation process.