本研究利用多孔陽極氧化鋁陣列進行定電位電沉積並針對三種製程-常壓製程、超臨界二氧化碳製程及乳化超臨界二氧化碳製程進行評估。首先，多孔陽極氧化鋁模板是以兩階段陽極處理法(Two-step)於草酸中以低溫定電壓中製成，於此法下成長出的陣列具有高規則度、筆直及高深寬比之結構。陽極處理後配合適當的基材及阻絕層(Barrier layer)移除程序以製備雙孔型陽極氧化鋁模板。接著將模板固定於工作電極並利用上述的三種製程中進行定電位電沉積。結果顯示乳化超臨界二氧化碳製程下，因超臨界流體低表面張力、高質量傳輸使其與常壓製程相比具有近快兩倍的沉積速率。此外，因乳化超臨界二氧化碳與氫氣的高溶解度，使得乳化超臨界二氧化碳製程在電沉積的同時能避免氫氣於孔洞中還原所產生的阻礙，唯另一沉積速率較快的原因。
本研究尚繼續延伸探討陽極氧化鋁內部及表面官能基及模板結構於三種製程下的影響。將製備完成的陽極氧化鋁置於真空加熱爐中以300 oC、600 oC及860 oC中進行熱處理24小時。結果發現於300 oC起熱處理的結果便能改變因陽極處理而滲入的氫氧基含量，至860 oC便能移除因陽極處理而滲入的草酸根離子，同時於此溫度下的陽極氧化鋁內部結構有交互擴散甚至封孔的情形發生。於熱處理後的模板利用三種製程中進行電沉積，結果顯示於300 oC、600 oC熱處理後的模板中進行電沉積並無明顯差異；然而，於860 oC熱處理後的模板中進行電沉積發現唯乳化超臨界二氧化碳製程能於模板底部進行填充電鍍，顯示經高溫熱處理表面改質後模板結構對於一般電沉積具有影響，而在此條件下乳化超臨界二氧化碳製程仍能進行填充電鍍，顯示其趨近於零之表面張力及高質量傳輸於此條件下仍能保持其高滲透性於高深寬比之結構中進行填充。

Electrochemical copper deposition in high aspect ratio nano-holes formed in anodic aluminum oxide(AAO) membranes was attempted by employing an emulsified supercritical carbon dioxide (scCO2) bath, in comparison with that performed using conventional process at ambient pressure. The AAO membrane with a thickness about 5 µm contained nano-holes with an average pore size of 30 nm and an aspect ratio around 150. Copper deposition in 40 vol% scCO2 bath at 50 oC and 10 MPa was conducted under constant potential condition. The effectiveness of copper filling into the nano-holes was evaluated by employing transmission electron microscopy(TEM) coupled with energy-dispersive X-ray spectroscopy(EDS), with the aid of Focused ion Beam (FIB) for samples preparation. The experimental results showed that copper filling into a high aspect ratio nano-holes employing scCO2 bath was more effective than that of conventional process at ambient pressure, as far as the depth and uniformity were concerned.

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