關鍵詞：微電鍍、銅鎳合金微結構、電阻溫度係數、奈米壓痕、腐蝕 ;ABSTRACT In this study, the microcolumn and micro-helix of Cu-Ni alloy were prepared by microanode-guided electroplating (MAGE). There are two kinds of electrolytes: 0.388 M nickel sulfate solution (the applied voltage from 3.8 to 4.4 V, and the bath temperature from 20 to 50 °C), and 0.272 M nickel sulfate solution (the applied voltage from 4.0 to 4.6 V, and the bath temperature from 20 to 50 °C ) with the gap between the microanode and the cathodic microcolumn was fixed at 50 μm. The results showed that the optimal surface morphologies were obtained with the voltage at 3.8 V and temperature at 50 °C, as well as the applied voltage at 4.0 V and temperature at 50 °C. The semi-quantitative analysis by EDS showed that the Ni-content of Cu-Ni alloys in both baths were increased either the applied voltage or elevated temperature. In the nano-indentation test, it was found that the Ni-content increased with the increase of applied voltage (from 4.0 to 4.6 V) and bath temperature (from 20 to 50 °C) of the 0.272 M nickel sulfate solution. The maximum hardness was 8.286 GPa of the Cu-Ni alloy microcolumn while the applied voltage at 4.6 V and bath temperature at 50 °C. When measuring the temperature coefficient of resistance, it was found that the minimum temperature coefficient of resistance was 23088 PPM/°C when the atomic ratio approaching the constantan alloy (Cu55Ni45, at 4.4 V and 20 °C). The corrosion resistance of the Cu-Ni alloy microcolumn displayed the minimum corrosion current density of 3.07 μA/cm2 at the applied voltage of 4.6 V and the bath temperature at 50 °C. The applied voltage of 4.4V is the optimal parameter in this study for manufacturing 3D Cu-Ni microhelices, and the finite element analysis (FEM) was applied for simulating the distribution of the electrical field of the helical column-diameter by COMSOL MULTIPHYSICS. The results showed that the uniform diameter can be obtained with the smaller angle between the microanode and the tip of microcolumn in the MAGE process, and the minimum variation of helical diameter can be obtained with parameter No. 3 in MAGE process.
Keywords: micro-electroplating, Copper-Nickel alloy microstructure, temperature coefficient of resistance, Nano-indentation, Corrosion.
