奈米碳管自1991年被發現以來，因其獨特的結構、機械性質以及電性…等，持續不斷的有相關研究投入，而利用其半導體特性以製作各種感測器元件方面，也一直有相關成果被發表，但多數均針對單根碳管的特性做探討，對於實際量產或批量製造，仍需要更了解其巨觀性質。
本研究利用酒精催化化學氣相沈積(Alcohol Catalytic Chemical Vapor Deposition , ACCVD)成長單壁奈米碳管薄膜，且一併探討製程中通入氨氣對碳管的摻雜效果。接著以積體電路相容製程製作光感測器元件，並針對不同光源下元件之電流-電壓特性做一系列之分析。
實驗結果顯示，氨氣處理並無法對奈米碳管進行有效摻雜，且會影響其品質。所製備之單壁奈米碳管薄膜光感測器，於大氣環境下，全波段的光源照射後確有3.3倍之電流增益，且隨光源強度增加，暗電流及光電流輸出穩定，但因氣體吸附效應所致，光電流增益並未達到一個數量級以上。尺寸效應方面，相同線寬情況下加大電極間距以增加受光面積，其所增加的光電流相較元件所增加的電阻仍太小。
綜合以上，若元件改以大線寬、短電極間距之設計，並阻絕氣體吸付效應的影響，應可有效提昇元件性能。

Carbon nanotubes(CNTs) was first found in 1991 and was massively studied since then due to its unique structure, mechanical and electronic properties. Because of the mention above, seminconducting CNTs have been employed to fabricate different kinds of functional sensor devices, but most researches are focusing on individual CNT, there are still many more macroscopic properties need to be verified for batch fabrication or commercial production.
In this research, Alcohol Catalytic Chemical Vapor Deposition(ACCVD) was applied to synthesis single wall carbon nanotubes(SWCNTs) thin-film, and the doping effects of additional purged NH3 will also be discussed. Furthermore, the I-V characteristics of photosensor fabricated by the IC compatible process will also be evaluated under different of light sources.
According to the results, the NH3 treatment process can not effectively dope into CNTs and will lose its quality. Under certain atmosphere, the SWCNTs thin-film photosensor were illuminated by a broadband light source and has a 3.3 times photocurrent gain which increase with higher light intensity. The measured darkcurrent and the photocurrent are stable with time passes, but the photocurrent gain is less than one order because of the probable gas absorbing effect. In the result of size effect, even with the same channel width, extended the gap distance between electrodes to larger the area which been illuminated, we found that the increased photocurrent can not contend with the raised resistance, and the total photocurrent gain was more unapparent than the one with small gap distance between electrodes.
Finally, we suggest that to reduce the gap distance between electrodes, extend the channel width and avoid the probable gas asorption may encourage the performance of the photosensor devices.

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