Investigation of the role of H-related defects in Al2O3 blocking layer on charge-trap memory retention by atomistic simulations and device physical modelling

In this work, we use atomistic simulation, consolidated by a detailed Al₂O₃ physico-chemical material analysis, to investigate the origin of traps in Al₂O₃ (in particular, Al- or O-vacancies and H-interstitials). It is shown that the leakage currents through Al₂O₃ layers, with different post-deposition anneals, are strictly correlated to the H content. Then, for the first time at our knowledge, the hydrogen-based trap features estimated by quantum simulations are introduced in a TANOS device simulator. A very good agreement is obtained between model and device experimental data, allowing for a clear understanding of the role of alumina H content on the retention characteristics of charge-trap memories.