Transfer of Positive Fixed Charge between Si and SiO_2 in Si/SiO_2 Interface with Hydrogen Migration

摘要

The transfer reaction of the positive fixed charge at the Si/SiO_2 interface accompanied by hydrogen migration, which is a basic phenomenon to consider negative-bias temperature instability, was investigated using the ab initio molecular orbital method. Comparing the activation energies, we determined the most likely reaction path. We found that the reaction path can be stabilized more by migration of an electrically neutral H atom from a Si substrate to a positively charged O atom than by migration of a proton from a Si substrate to an electrically neutral O atom. The calculated atomic charges and atomic spin densities also supported our conclusion.