Chemical and dielectrical characteristics of ultrathin oxides grown by atomic force microscopy and scanning electron beam

摘要

We report a comparative study on the chemical and dielectrical properties of ultrathin oxides grown by atomic force microscopy (AFM) and scanning electron beam (SEB) techniques. Oxide grown by AFM (AFM oxide) shows preferential etching as compared to oxide grown by SEB (SEB oxide). The structural and chemical features of these oxides were probed using time-of-flight secondary ion mass spectrometry (TOF-SIMS) time profiling. It was found that AFM oxide is richer in Si-H and Si-OH content, while SEB oxide is oxygen rich and relatively dense in structure. The dielectric strength of AFM and SEB oxides were further evaluated by conducting AFM (c-AFM). The current-voltage characteristics and dielectric breakdown probability of these oxides were compared. The correlation between Si-H and Si-OH site formation and its impact on the chemical and dielectrical stability of AFM and SEB oxides was discussed.