銅電析皮膜の表面形態と機械的性質におよぼす不純物の影響

抄録

We studied how impurities-Cr, Fe, Co, Ni, Zn, Ag, Cd and Sn-in electrolytes, prepared with recycled copper, affect surface morphology and mechanical properties, i.e., tensile strength and elongation-of electrolytic polycrystalline copper deposlts, 35μm thick. In additive concentrations of 0.001 to 10g/dm³, we found that Cr, Fe, Co, Ni, Zn and Cd are not introduced into copper deposits. In contrast, Ag and Sn were found in copper deposits at an Ag additive concentration exceeding 0.01g/dm³ and a Sn additive concentration exceeding 10g/dm³. Copper deposit morphology was characterized by the presence of large numbers of bumps surrounded by crystallographical planes and their (220) preferential orientation. For the Sn additive concentration of 10g/dm³, however, surface morphology consisted of fine semispherical bumps and an almost random orientation distribution. The tensile strength of copper deposits was found to depend strongly on copper crystallite size, independent of orientation.