Effect of oxygen on the diffusion of Al in Pt films

Abstract

Diffusion of Al in Pt films over the temperature range of 200°-600 °C has been studied in different ambients. A single phase of Pt 5Al3 is observed in forming gas at 200 °C, which starts to transform into Pt3Al above 400 °C. In the presence of oxygen, however, the formation of Pt5Al3 is completely suppressed at 200 °C and greatly reduced at 300 °C. It also slows down the transformation into Pt3Al at higher temperatures. These are in agreement with the predicted effect of oxygen on the diffusion of Al in Pt films.