本研究重點想探討奈米通道電晶體系統的反應時間，奈米通道電晶體最大的特點在於其擁有閘極效應，元件能利用閘極控制通道表面電荷密度進而控制奈米通道內正離子的傳輸，與其它奈米通道電晶體不同，本實驗室採用以矽為控制閘極製做奈米通道電晶體，目的在於簡化奈米通道電晶體的製程。
本研究首要目標即是做出本實驗室特有的奈米通道電晶體，在製作過程中遇到諸多困難，甚至為提高元件良率更換製程方法；待元件製作完成後，將透過測量閘極效應的電性量測驗證其奈米通道電晶體具有控制正離子傳輸的特性，而關於系統的反應時間這部分，則是採用給予閘極某一固定頻率的方波電壓下，測量奈米通道電晶體系統奈米通道內的傳導電流的變化。
實驗系統設置是將奈米通道電晶體放置KCl溶液中，根據最後研究結果顯示，如奈米通道電晶體系統可利用閘極電壓控制正離子的傳輸，則每次閘極改變皆會擾動系統，造成奈米通道內電流的變化，本研究依據閘極效應理論對此結果提出一個解釋說明；當本實驗室製做出通道大小為38nm的奈米通道電晶體，放置在0.001M KCl的溶液中，閘極變換在-4V與4V之間，在奈米通道內的電流變化率為89.5％，反應時間為1秒，也就是當系統在給予閘極頻率小於0.5Hz時能使系統可以達到平衡，在達到平衡後其傳導電流測量結果符合閘極效特有的電流特性，不僅如此透過改變施予閘極不同的方波振幅所得出的實驗結果也再次印證其元件具有閘極效應，本實驗室的奈米通道電晶體具有操控正離子的的傳輸。

The major work in this thesis is to study the reaction time in the nanofluidic transistors system. The nanofluidic transistors can control the transport of cation in the nano-scale channel by changing the surface charge density on the wall of the nanochannel, which, in term, can be modified by a voltage applied on a nearly gate electrode. We utilize a unique design of the nanofluidic transistor, where the silicon gate electrode surrounds the nano-channel.
The measurement of the gate effect of the electrical property confirms that the nanofluidic transistors can control the transport of cation. And the reaction time can be obtained by measuring the electrical current in the nanochannel while a square-wave gate voltage is applied. Our results showed that every time a sudden change in gate electrode potential would disturb the system and cause the changes of the current. We explained the consequence of disturbance with the conception of the gate effect. When our nanofluidic transistor was sited in the 0.001 M KCl solution, the magnitude of nanochannel was 38nm, and the gate electrode potential switched between 4V and -4V. The rate of current variation in nanochannel was 89.5％, and the reaction time of the system was 1s. In other words, when frequency of the applied square-wave gate electrode potential was less than 0.5 Hz, the nanofluidic transistor system could reach a steady state, and the electrical property satisfied the gate effect.

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