本論文主要研究五苯環(Pentacene)之氧化物五苯醌(Pentacenequinone)作為注入層(Injection layer)以及鈍化層(Passivation layer)之有機薄膜電晶體，因一般有機薄膜電晶體之金屬與半導體接觸方式為蕭基接觸，載子在傳輸時需要更大的能量跨越能障，因此接觸電阻上升，電特性下降，且有機薄膜電晶體之可靠度通常比無機薄膜電晶體還要差，原因在於有機材料容易受到水氣的影響，再加上水為極性分子，若穿透至半導體內部不但會造成缺陷增加，也會受到電壓的影響形成電偶極捕捉載子，造成臨界電壓偏移和特性劣化，因此本論文的主軸為改善薄膜電晶體之金半接觸以極增加元件之可靠度。
論文的一開始，我們研究使用注入層對於元件特性的改善，使用的材料五苯醌為絕緣層材料，因此可以做為注入層之材料，我們利用熱蒸鍍沉積不同厚度之注入層於有機半導體表面，比較元件電性差異，經由數據發現5 nm之厚度為最佳值，能夠改善金屬電極與有機半導體接面的接觸效應，降低接觸電阻並提升元件特性，且通道長度100 μm之元件改善程度比150 μm還要大，原因在於尺寸微縮時，接觸電阻佔總電阻的比例提升，所以改善的幅度有所差異，最後我們對於注入層進行表面形貌掃描，推論出注入層之成膜方式與電流傳遞方式。
同時我們發現元件在負閘極偏壓下，隨著注入層的厚度增加，臨界偏壓的偏移量也越小，推論其原因為注入層於背通道抵擋了水氣之入侵，因此我們在元件上方蒸鍍厚度為150 nm之PQ鈍化層，比較有無鈍化層之元件差異，從結果得知加入鈍化層並不會改變元件的特性，且靜置在相對濕度百分之五十至六十之大氣下九十六小時，其穩定性與壽命都比未使用鈍化層之元件好，在施加正閘極偏壓或負閘極偏壓之劣化測試下，加入鈍化層之元件在臨界電壓的偏移及電流衰減方面都有很大的改善。

This thesis applying pentacenequinone (PQ) as injection layer and passivation layer for organic thin-film transistors. We discuss the electrical characteristics and reliability with and without the additional layer.
Schottky barrier between metal electrode and organic semiconductor makes carrier transport efficiency decrease. As a result, the contact resistance increases and affects the electrical characteristic. Furthermore, organic material is more sensitive to the environment than inorganic material. Moisture easily penetrates into organic semiconductor and increases trap sites to catch carrier, therefore, the threshold shift and the reliability decrease. According to the above reasons, we focus on the improvement of performance and the enhancement on reliability in this thesis.
First, we use top contact structure and deposit different thickness of PQ on the active layer, finding out the best performance at the thickness of 5 nm. Injection layer changes the contact mode from schottky contact to quasi-ohmic contact and decreases the contact resistance. When the channel length decreases from 150 μm to 100 μm, the mobility improves from 15% to 79% that is caused by the contact resistance is in majority of total resistance. We also presume the electrical conducting model with injection layer by using AFM to scan the surface appearance.
In additional, we find out that the device with injection layer’s Vth shift variation is less than the device without injection layer under gate bias stress. Presuming the reason is the help of injection layer keeping back channel from the penetration of moisture, we start second part of experiment for adding 150 nm passivation layer on the device. The result indicates that the device with passivation layer have good reliability under atmosphere and different gate bias stress. Most important of all, using thermal evaporation to deposit passivation layer won’t degrade the device performance and without breaking vacuum to complete the device fabrication.

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