Fabrication process and leakage current conduction mechanisms of Al2O3 gate dielectric thin films

Al2O3 gate dielectric thin films are deposited on P-Si(100) substrate by the method of reacting magnetron sputtering and furnace annealing. The impacts of different sputtering atmospheres and annealing conditions are studied. The results show that annealing in N2 ambience at higher temperature can reduce the leakage current significantly, and annealing in O2 ambience can effectively decrease the oxygen vacancy in Al2O3 films. The study of the leakage current conduction mechanisms of Al2O3 gate dielectric films shows that the leakage is induced mainly by Schottky emission mechanism for substrate electron injection, while both Schottky emission and Frenkel-Poole emission mechanism may contribute to the leakage current for gate electron injection.EI0101109-11142