本文所推廣之複合式脈衝陽極氧化（Hybrid Pulse Anodization，HPA）技術的目的為抑制過多的焦耳熱的累積 ，並在較高的製程溫度與較高陽極氧化電壓中製備奈米多孔型陽極氧化鋁（Anodic Aluminum Oxide，AAO）模板。另外，以AAO製備成濕度感測器，並透過各式方法來增強該AAO的敏感度。本文以鋁薄片（Aluminum Foil）進行陽極氧化處理，而該氧化鋁在經過電場輔助的陽極氧化製程後，可以形成更厚的氧化鋁層，並產生規則排列的孔洞結構，其孔洞通道有極佳的垂直性。因此本實驗即選著了在草酸電解液中，針對各種陽極氧化條件，如：施加模式、較高正電壓、電解液溫度與擴孔時間下製備100 nm左右之陽極氧化鋁。再以場發射掃描式電子顯微鏡(FE-SEM)觀察AAO孔洞形貌，並使用ImageJ和WSxM等軟體去分析AAO孔洞表面形貌的SEM影像，加以探討當改變製程參數會有何影響並且量化之。另外，在AAO表面鍍上Pt薄膜作為電極，再透過不同的相對濕度來量測該感測器之電容值與電阻值。同時以磁場、濃度與電壓等來增強該感測器之整體敏感度。
本實驗成功的以HPA在室溫下（25oC）且較高電壓與較短的時間下製備出高規則排列之AAO模板，讓整體製程更為節省與有效益。而在AAO的應用部分，各式的方法都可大幅的提升濕度感測器之敏感度，解決了AAO濕度感測器在低濕度條件下缺乏敏感度之問題。

Anodic aluminum oxide (AAO) containing high-aspect ratio pore channels is widely used as a template for fabricating nanowires or other sensors. For AAO is prepared in oxalic acid, the anodizing potential is set as 40 V in order to balance the oxidation and dissolution rates. In practice, higher potential and high temperature are beneficial in increasing the pore size and growth rate. However, its increases the electrolyte temperature and therefore damages the pore structure. In addition, capacitive sensors based on anodic oxide aluminum film provide a fast and reliable means of sensing humidity. Moreover, the water molecules under a magnetic field preferentially form water clusters in which the dipole moments of the water molecules have a more orderly arrangement. In the present study, the joule heat problem is resolved by means of a high-potential hybrid pulse anodization (HPA) technique, in which a period of small negative potential is applied to suppress the Joule heating effect during the AAO preparation process. The SEM results show that HPA with an anodizing potential of 60 V results in an intact pore structure on the AAO surface. We also have investigated the sensitivity enhancement and its mechanism of the AAO humidity sensor by performing the sensing operation in the presence of an NbFeB magnet and increasing the concentration of electrolyte. The results show that the concentration and application of a magnetic field yields a linear-like relationship between the capacitance and the relative humidity.

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