Electrical characterization of rapid thermal annealed radio frequency sputtered silicon oxide films

Abstract

An investigation of the effect of rapid thermal annealing (RTA) on the electrical properties of if sputtered silicon oxide films was carried out. The films were prepared with the argon sputtering pressure varied from 2 to 10 mTorr. It was found that the insulating property of the films improved when deposited at lower sputtering pressure. The as-deposited film with the highest conductivity was selected for the RTA experiments. It was found that RTA at T>900°C or at longer times reduces the interface trapped charge (Dit) and the fixed charge (Qf) densities to 1.8×1012 eV-1 cm-2 and 1.5×1012 cm-2, respectively. We concluded that RTA at a longer period of time is more effective in improving the film quality than raising the annealing temperature. Postmetallization anneal reduces Dit further to 3.5×1011 eV-1 cm-2. © 1996 American Institute of Physics.