抄録
Palladium was electroplated on copper at 50-200A/m2 in a chloride bath. The current efficiency for palladium deposition was nearly equal to 100% at 50A/m2 and smaller at a larger current density. Hydrogen in the electroplating palladium film was analyzed by measuring its thermal evolution spectrum. Two peaks were observed in the thermal spectrum of the hydrogen evolution rate. The lower and higher temperature peaks originated in evolution of the hydrogen dissolved in normal lattices of palladium atoms and the hydrogen trapped by lattice defects such as dislocations and grain boundaries, respectively. The concentration of hydrogen was calculated from the area of the hydrogen evolution peaks. The concentrations of the lattice-dissolved hydrogen and the trapped hydrogen in the palladium film electroplated at 50A/m2 were 14 and 5 mass-ppm, respectively. The concentrations of hydrogen were higher at a larger current density.
