A new post-deposition annealing method using furnace N2O for the reduction of leakage current of CVD Ta2O5 storage capacitors

In this work, we present a new post-deposition annealing technique that employs (f) under bar urnace annealing in <(N2O)under bar> (FN2O) to reduce the leakage current of CVD Ta2O5 thin films. The decrease in leakage current can be attributed to the reduction of oxygen vacancies by the atomic oxygen species generated from the dissociation of N2O at high temperatures. Compared with furnace annealing in O-2 (FO) and rapid thermal annealing in N2O (RTN(2)O), FN2O annealing proved to have the lowest leakage current and the most reliable time-dependent dielectric breakdown (TDDB). Moreover, FN2O annealing may be conducted in conventional oxidation furnaces in batch order, and is therefore perfectly suitable for mass production.