Comparative study on phase formation in Al-Pd thin film by ion beam mixing and thermal annealing

Abstract

Ion beam mixing and/or thermal annealing were conducted to study the phase formation and dissociation in Al-Pd thin films. The films were prepared by sequential evaporation, Ar⁺ ion mixed, annealed at 350 °C for 1 h under vacuum and then analysed by RBS, TEM and XPS. The intermetallic compounds formed by ion mixing alone are found to be Al₃Pd₂ and AlPd at a dose of 1.5 × 10¹⁶ Ar⁺ cm⁻². Thermal annealing after this radiation gave two new phases of Al₃Pd and Al₃Pd₅ in addition to Al₃Pd₂ and AlPd. For an as-annealed sample without Ar⁺ bombardment, the observed phases are Al₃Pd, Al₃Pd₂ and AlPd. The different behaviours in phase formation between ion beam mixing and thermal annealing are presented.