釔安定氧化鋯(YSZ)與氧化釓摻雜氧化鈰(GDC)材料，因其具有較佳的抗還原性及優異的機械性質，為目前工業界最常應用在固態氧化物燃料電池(SOFC)與含氧感知器的氧離子導體，可使元件具有一定程度的可靠度(reliability)。但由於需要在很高的工作溫度且長時間操作，因此本實驗以微波方式進行電解質的優化，運用微波的非熱活化機制[43-50]，探討以微波場促進材料中晶格振動，提升離子或點缺陷遷移率，運用這層關係降低本身的操作溫度並提升氧離子的擴散速率。結果顯示YSZ電解質以微波優化在300oC時將離子導電率提升約38倍。而低溫微波熱處理對GDC電解質的影響也將在本文中討論。
本研究的另一課題，使用射頻式-磁控濺鍍製作奈米8 mol.%釔安定氧化鋯薄膜於矽(100)單晶基板與氧化矽基板上，反應氣體Ar:O2比為25: 5 (s.c.c.m)環境下，探討薄膜的微觀、結晶性和基材匹配性，並利用交流阻抗分析儀，量測室溫下的離子導電率。同時，藉由穿透式電子顯微鏡觀察奈米8YSZ薄膜與矽(100)單晶基板界面微觀，模擬其晶體結構匹配性、界面應力與空缺分佈為了瞭解8YSZ薄膜化是否有助於離子導電率的提升。
根據文獻中，J. G. Barriocanal等人的研究[22]，將YSZ以人工超晶格的方式成長於STO基板，其聲稱，若將YSZ電解質奈米化，能使離子導電率獲得爆炸性的提升，主張藉由異質方式成長，使得界面處存在著高濃度的氧空缺。但是X.Guo則對其文章發表評論[23]，認為並無有力證據證明界面處存在非序化的空缺，且認為離子導特性之優異主要貢獻是來自於P型STO基板，因此不可以忽略基板在電性量測上的貢獻。而本研究則是成長奈米薄膜YSZ於矽基板，利用半導基材的特性，以局部性電場趨迫氧離子的遷移，使離子導獲得大幅度得提升。我們以白金電極/YSZ薄膜/白金電極通以氣氛，以極限電流響應的程度，釐清YSZ/Si複合層中的導電機制。這是目前其他文獻所沒有使用的方式，我們希望以這種極限電流響應的方式，利用半導特性的基板，引導出奈米電解質薄膜中的氧離子，並且使其在室溫下工作的氧氣感測器。

Yttria stabilized zirconia (YSZ) and gadolinia doped ceria (GDC) are common electrolytes for applications in ionic conductor of oxygen sensor or solid oxide fuel cell (SOFC) because of their outstanding reduction-resistances, better mechanical properties and reliability than other electrolytes. But their operation temperatures are too high to enhance their evaluation. In this work, we report that a microwave process could enhance ionic conductivity, showing up to 38 times at 300oC, in YSZ specimen. Huge enhancement of ionic conductivity in YSZ is observed by using in-situ microwave emission -ionic conductivity measurement and maintains the highest value after heat treatment. In this case the effect is shown to depend upon the ionic diffusion and polarization phenomena. Different results on the morphology of the microwave induced conductivity in mixed conductor GDC specimen are also presented. This is a direct experimental confirmation of the theory that suggests a mechanism of nonthermal influence of high frequency electromagnetic field on charge and mass transport in solids. The microwave radiation generates a nonthermal phonon distribution in the poly-crystalline lattice and thereby enhances the mobility of crystal lattice ions. This leads to significant reduce the operation temperature and enhance oxygen diffusion. It is also good for developing a new technique to disrupt oxygen vacancy association and elemental clustering, through the intrinsic mobility of point defects to transform the micro-domains to nano-size by microwave treatment.
The other part of this research was using Magnetron-sputtering to sputter 8mol% Yttria-stabilized Zirconia (YSZ) in p-type silicon (100) and silica substrate. The reaction gas ratio Ar: O2=25:5 (s.c.c.m). According to some researches, Garcia-Barriocanal et al. [22] claimed that the enhancement of the conductivity in nano-YSZ film is observed, along with a YSZ layer thinkness-independent conductance, showing that it is attributed to the high oxygen vacancy concentration and the high mobility at the YSZ/STO interfaces. But, Xin Guo [23] argued that the claimed ionic conductivity lacks experimental support and that the observed conductivity enhancement is most probably due to the p-type conductivity of substrates. We report electrical manipulation of oxygen ion migration in a nano-YSZ film, in which localized electronic field of the p-type conductivity of substrates are responsible for the huge ionic conductivity enhancement. Sudden enhancement of the current sensing property of the Pt electrode/ nano-YSZ film/ Pt electrode planar structure was also observed to separate the conductivity mechanism for the YSZ/ substrate di-layer composites. The relative current at which localized potential field occurs can be manipulated by modifying the substrates conductivity through application of electric fields in a di-layer structure. Electrically assisted ionic conductivity has been demonstrated through the effect of substrate. This electrical manipulation offers functionality not previously accessible based on the interface process in nano-YSZ film/ semi-conductor substrate and may become useful for enhancing ionic conductivity of nanoscale YSZ film for oxygen sensor working at room temperature.

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