High-quality ultrathin gate oxide prepared by oxidation in D2O

In this letter, we present a process to incorporate deuterium at the Si/SiO2 interface using deuterium oxide (D2O) as an oxidizing gas. We have investigated the electrical and reliability characteristics of ultrathin gate oxide grown in D2O ambient. Compared with a control oxide grown in H2O, an oxide grown in D2O exhibits a significant reduction of charge trapping and interface state generation. Based on secondary ion mass spectroscopy analysis, we found a deuterium-rich layer at the Si/SiO2 interface. The improvement of electrical and reliability characteristics can be explained by the deuterium incorporation at the Si/SiO2 interface. (C) 1999 American Institute of Physics. [S0003-6951(99)00305-8].