有機薄膜電晶體(Organic Thin Film Transistors，OTFTs)年來受到廣泛的研究，因其有低成本、低溫製成及可撓曲的優點，並且可以利用溶液製程來製作。但其相對於非晶矽的薄膜電晶體來說，載子遷移率(Carrier mobility)比較小以及臨界電壓(Threshold voltage)偏大都是等待改善之目標。
本論文中我們利用噴印技術製備有機薄膜電晶體的奈米複合絕緣層，免除傳統之黃光製程，並且在有機絕緣層高分子材料cross-linked poly(4-vinylphenol) (PVP)中摻雜TiO2之奈米粉體，以期提高絕緣層之介電常數，進而改善有機薄膜電晶體之特性。為了把TiO2奈米粉體分散得夠小且均勻，我們利用高速珠磨(Pearl mill)分散技術來達到此需求，並對其研磨分散條件做探討。接下來我們對噴印製程條件之驅動電壓大小、操作頻率以及壓電波形對噴墨情況最佳化，成功地噴印出奈米複合絕緣層，達到直接圖案化的目的。
我們在以噴印取代傳統旋轉塗佈製作之奈米複合絕緣層上，蒸鍍Pentacene來製作有機薄膜電晶體。藉由摻雜TiO2的奈米複合絕緣層，我們成功的將載子遷移率提升到0.58 cm2/ Vs，並把臨界電壓降低到-5.4 V。最後，我們以XRD、SEM及Raman光譜來探討Pentacene沉積在這些不同之絕緣層上的傳輸行為。

Recently, Organic Thin Film Transistors (OTFTs) have been studied widely because of potential applications in low cost, low-temperature process and flexible displays. They can be fabricated by easy processes based on solution methods. But the mobility of OTFTs is lower and the threshold voltage is higher than amorphous Si TFTs.
In our study, we prepare the nanocomposite dielectrics by ink-jet printing to avoid the photography process. The nanocomposite dielectrics consist of cross-linked PVP and high-k TiO2 nanoparticles used to increase the dielectric constant and hence improve the performance of OTFTs. In order to well disperse the TiO2 particles, we utilize pearl mill to achieve our requirements. Then we optimize the parameters of ink-jet printing, including voltage, frequency and waveform. We successfully print dielectrics patterns, accomplishing the purpose of directly-patternable.
We deposit pentacene on the nanocomposite dielectrics of best performance by thermal deposition process to demonstrate OTFTs. We eventually demonstrate high performance OTFTs of mobility 0.58 cm2/Vs and Vth-5.4 V. And we used XRD, SEM, Raman spectroscopy to help us analyze the transfer characteristics of pentacene films and the performance of OTFTs.

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