Charge trapping analysis of Al2O3 films deposited by atomic layer deposition using H2O or O3 as oxidant

In this work, the authors focus on the charge trapping behavior of Al2O3 layers deposited by atomic layer deposition. The goal is to give an insight into the effects of the oxidant source (H2O or O3) and the postdeposition anneal on the charging phenomena and the generation of new defects during electrical stress. For this purpose, current–voltage, capacitance–voltage, and conductance–voltage characteristics of Al/Al2O3/p-Si capacitors are analyzed before and after constant voltage stress and several phenomena such as the generation of neutral traps in the bulk dielectric, slow states, interface states, and charge trapping related degradation during the electrical stress are investigated. Finally, the impact of the oxidant source on the Al2O3 layer reliability is discussed.