Effective Capture Cross-Sections of Traps in High-k Gate Dielectrics

Abstract

We report an experimental study of captures cross-sections of traps in some ultra-thin high-k gate dielectrics. We focus on a surprising finding that the effective capture cross-sections seemed to be extraordinarily small (between 10e-22 and 10e-19cm2) compared. We arrived at the conclusion that the low values of the effective capture cross-section arise from significant de-trapping, which is not accounted for in the trapping models used in extracting the trap cross-sections. The results of this study point out that it is important to consider the film thickness and leakage current when extracting capture cross-sections in ultra thin gate dielectrics.