A kinetic study on the electrodeposition of Ni-Cr alloy on copper for embedded resister layer in PCB

摘要

The thin film resistors such as Ni-Cr alloy could be formed by the electrodeposition method for embedded passive device in printed circuit board. A kinetic study on the electrodeposition of nickel-chromium alloy on copper has been performed using a rotating disk geometry. Activation energies of nickel and chromium in the temperature range between 15°C and 35°C were 8.9kcal/mole and 3.5kcal/mole, respectively. The electrodeposition rate of nickel seems to be controlled partly by electrochemical reaction and partly by mass transport, namely mixed controlled. However, that of chromium seems to be controlled by mass transport. As the amount of chromium in deposit increased, the electric resistance of deposit surface increased. The maximum electric resistance of nickel-chromium alloy deposit was 78.6Ω /□.