Abstract

The process of dc magnetron sputtering can lead to the deposition of dense oxide films. Because of the high density of the films, they are resistant to the penetration of moisture. Improvements in magnetron sputtering technology have made it possible to use a lower gas pressure during deposition. This lower pressure reduces the level of water incorporated into the films during deposition. We report the results of a study of single-layer films of the oxides of silicon, aluminum, and titanium. An 8-in. dc magnetron source was used for the deposition. Metal targets were used for each material, and a mixture of argon and oxygen was employed during the deposition. An aluminum dopant was used with the silicon target to minimize contamination. The deposition parameters studied were the target voltage, the total pressure during the deposition, and the partial pressure of the oxygen. Several source geometries were tested in an attempt to optimize the deposition rate. Moisture content of the films was determined by spectral transmission scans over the water absorption bands at 2.7 μm. For total pressures of 2 × 10^-4 Torr or less, the films were found to be free of water.

© 1991 Optical Society of America