本研究以乳化超臨界二氧化碳電鍍法，於高深寬比之微孔中沉積鎳-磷合金鍍層，評估在無添加促進劑及抑制劑的鍍浴中，進行超填充的可行性。研究中亦探討電流密度、系統壓力及微孔孔徑的改變，對微孔基材上鍍層均勻性的影響。本研究採用的微孔模具有兩種，分別是以金屬孔加工的方式製備之黃銅模具，孔徑為250 μm、500 μm與750 μm，以及雷射鑽孔加工之氧化鋁基板，孔徑為50 μm。實驗結果顯示，以乳化超臨界二氧化碳電鍍法在銅模微孔中所沉積之鍍層，其微孔內外的鍍層厚度差值較常壓電鍍法所披覆之鍍層差為小，顯示利用該製程可獲得披覆均勻的鍍層。當微孔之孔徑尺寸小於500 μm時，以傳統鍍浴無法將鎳-磷鍍層披覆於微孔中。若將傳統鍍浴與超臨界二氧化碳乳化後，降低鍍浴之表面張力，可有效於微孔中披覆鎳-磷合金鍍層。另外，在雙向導電微孔模具，以乳化超臨界二氧化碳電鍍法沉積鎳-磷合金鍍層具有較常壓製程優異的填孔效率，但仍無法將微孔完全填滿。若改用單向導電微孔模具，並在適當的電流密度以及製程配合下，可以有效避免微孔提早被封閉導致無法填滿的問題。証實從底部以單方向沉積電鍍法，於乳化超臨界二氧化碳鍍浴中，可將微孔完全填滿。

In this study, Ni-P coatings electrodeposited into high-aspect-ratio micro-holes via emulsified supercritical carbon dioxide (sc-CO¬2) bath without accelerator and inhibitor addition to evaluate the possibility of super-filling. The effect of current density, pressure of electroplating system and diameter of micro-holes on the uniformity of the coating deposited on micro-hole substrate were also investigated. There are two types of micro-hole mold in this research, such as drilled brass micro-hole mold (φ = 250 μm, 500 μm, and 750 μm) and laser-drilled Al2O3 micro-hole mold (φ = 50 μm) . The experimental results showed that the difference in thickness between inside and outside layer of brsss micro-holes, which was deposited in emulsified sc-CO2 bath, was smaller than that fabricated in conventional electroplating process. It revealed that the uniform coating could be obtained by the sc-CO2 electroplating process. The Ni-P alloy coating couldn’t be deposited in conventional bath, while the diameter of the brass micro-hole was below 500 μm. In contrary, the Ni-P alloy coating was successfully deposited on the micro-hole, due to its low surface tension. In addition, the Ni-P coating deposited on double-side conductive micro-hole mold in emulsified sc-CO2 bath exhibits the better filling efficiency as compared to that deposited in conventional bath but it still cannot achieve super-filling condition. If the conductive layer of micro-hole was modified to single-side, the existence of voids and seams could be precluded, which resulted from mouth of micro-hole sealing before completely micro-hole filling. The results demonstrate that the micro-hole could be completely bottom-up filled via emulsified sc-CO2 electrodeposition method.

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