本研究中，我們針對了耐火性鉭矽化物奈米線以及過渡性金屬氧化物奈米線進行了電性的量測與結果探討。在鉭矽化物奈米線的電性量測中，首先藉由兩點探針的量測方式來求得此奈米線的電壓－電流特性，但是量測的結果發現，由於接觸電阻的影響，兩點探針的量測方式並不能真正求得奈米線本身的電阻值。為了降低甚至排除接觸電阻的影響，我們朝著兩個方向來著手。第一，以四點探針的量測方式來取代兩點探針的量測；第二，試著增加接觸電極的寬度以期待接觸電阻的降低。結果顯示，在進行四點探針的量測時，當任何一根電極的接觸電阻與其他電極相差太大時，四點探針的方式亦難以量測出奈米線的電壓－電流特性曲線。因此在實驗的過程中，我們另以三點探針的量測方式來取代四點探針，並探討其中的差異性。此外，在第二種方法中，從實驗中觀察到接觸電極的線寬與兩點探針量測的電阻值並沒有任何的依存關係。於此，我們認為有機溶劑在奈米線表面的污染與殘留是造成不同元件間接觸電阻差異的主因。因此，對於另一種可以降低接觸電阻的方式－快速熱退火處理－也在本研究中加以運用與探討。另一方面，對於鉭矽化物奈米線的低溫電阻量測，證實了此奈米線具有金屬的傳輸特性，這項結果符合了理論上的預期。最後，經由量測鉭矽化物奈米線可承受的最大電流極限，我們觀察到此奈米線可承受的電流密度高達3×108 A cm-2，足以與奈米碳管匹敵，並且提供了新世代奈米元件間作為連結材料的新選擇。
在過渡性金屬氧化物奈米線的量測中，量測的對象是針對氧化鎢奈米線與氧化鐵奈米線。由於它們皆屬於半導體材料，因此它們的場效特性是令人期待的。在氧化鎢奈米線的量測中，使用的接觸電極材料包括了鉻、鈦、金、鎳，但是我們從量測出來的電壓－電流曲線發現，這些材料皆無法與此奈米線形成良成好的歐姆接觸。而在閘極電壓的施加下，也並沒有出現任何的場效特性。另外在真空與大氣環境下的電阻值量測，亦無出現因氧氣的表面吸附而造成電阻上的差異。因此，我們猜測這可能由於氧化鎢奈米線具有相當高的功函數以及能隙所致，在電性表現上比較接近於本質的半導體行為。
另外對於氧化鐵奈米線的電性量測結果顯示，在閘極電壓的施加下，其電壓－電流曲線呈現了明顯的n型場效特性行為，這對於未來的功能性奈米元件的發展是相當有潛力的，但由於量測的結果中電流出現不穩定的震盪行為，我們很難加以分析出相關的數值(載子移動率、載子濃度)。另一方面，在真空量測的部分，我們觀察到氧化鐵奈米線的電阻值與大氣量測下做比較，明顯下降了許多。這也證明說氧化鐵奈米線具有優異的感測性質。由於在試片準備上遇到較大的困難，因此並沒有太多的量測數據可供比較。在此僅提供初步的量測來證明氧化鐵奈米線具有相當看好的應用潛力。

In first part of the experiments, we carry out a series of electrical measurements and discussions on the TaSi2 nanowires. In this research, we get a large discrepancy in the two-probe measured resistance from various two-probe devices. In general, a total resistance containing both of the contact resistance and the wire resistance is measured by the two-probe technique. In order to avoid the influence by contact resistance, we solve the problem in two directions. First, the four-probe measurement technique is utilized to get real resistance of the TaSi2 nanowires itself. Second, we want to reduce the effects of contact resistance by increasing the width of contact electrode. But in this part, the measured two-probe resistance doesn’t show much dependence on different contact electrode width. Hence, we suspect that this may be caused by the residual solvent contaminants on the nanowires before metal deposition. On the other hand, I-V measurement at different temperatures (T＜300K) reveals the TaSi2 nanowire with a residual resistance at very low temperature exhibits a classical metallic behavior. Finally, we find the TaSi2 nanowire can bear a high current density of 3×108 A/cm2 before failure through the melting test. The result indicates that TaSi2 nanowire may be a promising candidate for the next generation nano-device interconnecting application.
In the second part, tungsten oxide and iron oxide nanowires are studied. Due to their semiconducting nature, we are interested in the exploration of their field effect characteristics. In the measurement of tungsten oxide nanowires, we don’t find a proper ohmic contact metal in the available materials. In addition, no field effect appears when applying high gate voltage from +20 volt to -20 volt. By exploring its surface chemistry behavior, the resistance of WO3 nanowire is not changed when measuring in the air and in the high vacuum environment. This is different from the behavior exhibits in the Fe2O3 nanowires. On the other hand, due to the semiconducting property of the Fe2O3 nanowire, it has the potential application in the nano-scale field effect transistor. But due to the difficulty in sample preparation, there are not much data to express in this study.

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