SILVER-PALLADIUM ALLOY PARTICLE-PRODUCTION BY SPRAY-PYROLYSIS

Spray pyrolysis was used to produce submicron Ag-Pd metal alloy particles for applications in electronic component fabrication. The particles were prepared in nitrogen carrier gas from metal nitrate precursor solutions with various compositions. The Ag-Pd alloy was the predominant phase for reactor temperatures of 700 degrees C and above for all compositions. The 70-30 Ag-Pd particles were fully dense at 700 degrees C, but an increased reaction temperature was necessary to produce dense particles at higher Pd to Ag ratios. The extent of palladium oxidation was suppressed with increased amounts of Ag. Single-crystal particles could be produced at sufficiently high temperatures. These results show that particle phase composition, size, oxidation behavior, and morphology can be controlled by the Ag-Pd ratio in the precursor solution and by the reaction temperature.