光感性低介電常數材料於後通道蝕刻薄膜電晶體上之研究

Study on Photo-Sensitive Low Dielectric Materials Passivation on Back-Channel-Etched Amorphous Silicon Thin Film Transistors

江政禕(Cheng-Yi Chiang)

指導教授 ： 葉鳳生 ； 張鼎張

國立清華大學/電機資訊學院/電子工程研究所/碩士(2006年)

https://doi.org/10.6843/NTHU.2006.00477

摘要

摘要 本論文研究感光性低介電常數材料於薄膜電晶體技術上的應 用。由於感光性低介電常數材料應用於薄膜電晶體 (TFT) 元件上的 平化保護層 (planarized passivation layer) 時，除了其具有高透光率 (> 90% at 300-800 nm)、低的光漏電以及好的平坦化 (planarization) 能力之外，還能夠提高薄膜電晶體顯示器的開口率 (aperture ratio)， 降低電晶體陣列連線中電阻-電容延遲時間 (RC delay time)。更重要 的是,材料的感光性更可簡化製程及減少製程步驟。因此，感光性低 介電常數材料於薄膜電晶體顯示器上的研究與應用，便成為重要的顯 示器技術發展趨勢。本論文選擇了兩種種具有潛力的感光性低介電常 II 數材料做為研究主題。 在對薄膜電晶體上的應用，保護層對元件電性的影響是最重要的 課題。我們在本論文中分別探討了兩種感光性低介電常數材料與傳統 氮化矽保護層材料對元件特性的影響。 研究的總結，我們發現感光性低介電常數材料作為保護層，在照 光操作下對元件並不會產生太大的影響。另外在可靠度方面，元件特 性表現亦佳。所以，未來感光性低介電常數材料薄膜將有可能替換傳 統氮化矽保護層，成為應用在薄膜電晶體保護層方面的候選人。

關鍵字

非晶矽 ； 薄膜電晶體

並列摘要

Abstract
In this thesis, we investigated the application of photo-sensitive low
dielectric passivation materials for thin-film-transistor (TFT) technology.
photo-sensitive low dielectric passivation materials has the properties of
the high transmittance (>90% at 300~800 nm), low photo leakage current
and good planarization for TFT passivation layer. In addition, it can
effectively increase the aperture ratio of display matrix and reduce
resistance-capacitance delay (RC delay). More importantly, the
photosensitivity of material property makes to simplify process and
reduce fabrication steps. Therefore, the application of the photo-sensitive
low dielectric passivation materials on TFT device has become one of the
most important issue for flat panel display. In this study we have
investigated two of the promising candidates of photo-sensitive low
dielectric passivation materials for TFT array technology application.
In TFT process, the effects of passivation layers on device electrical
characteristics are the most important issue. In this study, the effects of
two kinds photo-sensitive low dielectric passivation materials and
conventional silicon nitride passivation layer on device electrical
characteristics are discussed.
In conclusion, we have found that the leakage of devices with
photo-sensitive low dielectric passivation is little changed by illumination.
Otherwise, device performance exhibits also well in reliability. This
indicates that photo-sensitive low dielectric passivation materials are the
most possible candidate to replace the conventional SiNx passivation
layer on TFT device in the future.

並列關鍵字

amorphous silicon ； thin film transistor

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