Conduction mechanisms and interface property of silicon oxide films sputtered under different oxygen concentrations

An investigation on the effects of oxygen mixing in the sputtering gas and rapid thermal annealing on the electrical properties of radio frequency sputtered silicon oxide films has been carried out. The conductivity of the oxide film decreases as the concentration of oxygen in the sputtering gas increases, and also for rapid thermal anneal temperatures higher than 900 degrees C. Transport mechanisms for films annealed for 50 and 200 s were found to be that of Schottky emission and space charge limited conduction, respectively. From the capacitance versus voltage measurements, it was concluded that the improvement in the oxide quality of the annealed films was not related to the reduction of the interface trapped charge density. (C) 1998 American Institute of Physics.