本研究以單軸微動機構控制鉑絲（直徑125μm）陽極之間歇垂直移動在瓦茲鍍鎳液中，進行直流、脈衝電析，以期在銅片陰極上局部析鍍出平整、顆粒細緻及直徑一致之鎳柱。 直流電析法結果顯示：（1）陰陽兩極間之電壓在5 - 7V下可獲得鎳柱，電壓愈大析鍍局部性愈好，但析鍍物顆粒愈粗；表示愈不平整。（2）陰陽兩極間距離在5 - 100μm可析鍍出鎳柱，鎳柱結構隨兩極間距之增加，組織愈細緻平整，但對析鍍局部性有負面影響。（3）適量添加糖精（1mM）至鍍浴，可促進析鍍物顆粒細化及表面平整。 脈衝電析法結果顯示：（1）脈衝析鍍法比直流電析鍍法較能獲得平滑組織之鎳柱。（2）變形之脈衝電流比一般脈衝電流較能獲得平整細緻之鎳柱。 經由陰極動態電位極化曲線之分析，配合掃描式電子顯微鏡之觀察，本研究提出微電析過程中微鎳柱的生長模式及析鍍物成核、成長的機理。 Localized electroplating of nickel on copper substrate was conducted in a watts bath to obtain a nickel column. This electroplating was carried out by means of a specially designed anode, that is a platinum wire(diameter 125μm) moving vertically in micro-steps. Direct and pulse current are used as the power source. The results for the direct current electroplating indicated (1) a nickel column can be obtain when the bias of the electrodes is controlled at 5-7V. The higher the bias, the better the localization, and the more coarse of the deposit. (2) The gap between the electrodes affects the microstructure of the nickel column. In the gap ranging from 5 to 100μm, the greater the gap, the more dense and refined grain of the nickel column, but the worse localization. (3) An additive of 1mM saccharin sodium added in the bath results in grain-refining and surface leveling of the nickel column. The results for the pulse current electroplating indicated (1) pulse plating is better than dc plating to obtain a dense and smooth nickel column. (2) modified pulse current is better than the common pulse current to obtain a good nickel column. The microstructure of the nickel column was examined through scanning electron microcopy at the initial stage in the process of electroplating. In addition to the microstructural examination, the study of cyclic cathodic potentiodynamic provides useful informations for the mechanism elucidation of the localized electroplating.
