本實驗研究著重於有機場效電晶體的磁效應來源與機制探討，透過我們實驗室製程以成熟的有機場效電晶體來做量測。第一部份我們以單載子傳輸的有機場效電晶體做磁效應量測，發現只有照光才有磁電導效應，明顯指出了磁效應來源與激發態有關。第二部分以雙載子傳輸的有機場效電晶體做磁效應量測，不同於已往團隊，我們所得到的磁電導變化曲線線形明顯，有利於之後做模擬分析。而該部分的磁效應來源也是與激發態相關，再來我們透過激發子漂移距離的改變，發現主要機制是以分裂(Fission)這機制在磁場下會影響單重態變成三重態激發子的數目，因此產生正磁電導，然後我們也改變了幾項實驗條件來證實機制的正確性。最後我們這實驗提出不同於已往在長通道的電晶體下依舊可觀察到磁效應，而來源則為外加磁場影響的分裂(Fission)機制所造成。

We investigated magneto conductance(MC) responses in pentacene-based field-effect transistors (FETs). The first part of our research is focus on unipolar OFET which was only found the MC under photo-excitation. Obviously, this effect is dependent to excited states. The second part is focus on ambipolar OFET. We got good performance of lineshapes under magnetic field which is advantage of data analysis in the future. The magnetic field effect in this part is dependent to excited states, too. We found that "Singlet Fission" affects numbers of singlet to triplet excitons through the variance of excitons diffusion distance. Therefore, "Singlet Fission" under magnetic field leads to ＋MC. After this, we proofed whether this magnetic field effect works by substitute of different condition. Finally, our work suggests that MC response is still observable in long channel length FETs, which is attributed to the long lifetime of the triplet exciton follows by "Singlet Fission."

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