Effects of Electroplating Current Density and Duty Cycle on Nanocrystal Size and Film Hardness

  • Sun, Yong-Bin (Semiconductor-Display-Mechatronics Program, The Graduate School of Construction Engineering and Industry, Kyonggi University)
  • Received : 2015.03.09
  • Accepted : 2015.03.23
  • Published : 2015.03.31

Abstract

Pulse electroplating was studied to form nanocrystal structure effectively by changing plating current density and duty cycle. When both of plating current density and duty cycle were decreased from $100mA/cm^2$ and 70% to $50mA/cm^2$ and 30%, the P content in the Ni matrix was increased almost up to the composition of $Ni_3P$ compound and the grain growth after annealing was retarded as well. The as-plated hardness values ranging from 660 to 753 HV are mainly based on the formation of nanocrystal structure. On the other hand, the post-anneal hardness values ranging from 898 to 1045 HV, which are comparable to the hardness of hard Cr, are coming from how competition worked between the precipitation of $Ni_3P$ and the grain coarsening. According to the ANOVA and regression analysis, the plating current density showed more strong effect on nanocrystal size and film hardness than the duty cycle.

Keywords

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