Feasible Time Evolution Model That Predicts Breakdown in Thin SiO2 Films within Unstressed Interval after Constant-Current Stress

Abstract

This paper proposes a poststress time evolution model for sub-10-nm thick SiO2 films for degradation prediction and the extraction of trap-related parameters. The model is based on the understanding that the degradation in thin SiO2 films continues within the unstressed interval. The phenomenon is captured by an analytical expression that indicates that the time evolution of SiO2 film degradation roughly consists of two stages and that the degradation is more likely to occur if water molecules are present. It is demonstrated that the simple analytical model successfully reproduces measured results. It is also suggested that the degradation process considered here is related to oxygen diffusion in the resistive transition process.