考量製程變異、老化效應與撓曲效應之軟性薄膜電晶體電路的直流分析

DC Analysis for Flexible TFT Circuits Considering Process Variation, Aging Effects, and Bending Effects

馬恩華(En-Hua Ma)

指導教授 ： 李建模

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.01642

摘要

薄膜電晶體有越來越多的應用在大面積、軟性電子電路以及可印刷式電子電路上。軟性薄膜電晶體技術相較於傳統的矽技術有許多的優點，例如較低的成本以及較短的製作時間。目前軟性薄膜電晶體最大的問題在於當電晶體受到撓曲時會造成漂移率的改變以及當電晶體在工作時臨界電壓改變非常的迅速。綜合以上兩點會導致晶片的良率大幅度下降。這篇論文提出一個軟性薄膜電晶體的分析軟體(FlexiAnalyzer)，這個分析軟體提供四種分析: 良率分析、老化分析、效能分析、弱點分析。這個分析軟體考量三種重要的效應: (1)製成過程導致臨界電壓的改變、(2)老化效應導致臨界電壓的改變、(3)撓曲效應導致漂移率的改變。模擬在8um非晶矽薄膜電晶體製成下六種不同的有機發光二極體的驅動電路，實驗結果顯示良率在不同的電路上有明顯的差別。這個分析軟體提供使用者去估計軟性薄膜電晶體電路的效能與良率。

關鍵字

SPICE ； 軟性電子 ； 電路分析器 ； 老化效應 ； 撓曲效應

並列摘要

Thin-film transistors (TFTs) technology is widely used in large area, flexible and printed electronics. Flexible TFT technology has many advantages over conventional silicon technology such as low cost and short manufacturing time. Currently the problem of flexible TFT technology is the change in mobility when the TFT is bent and the shift in threshold voltage is fast when TFT is operated. With those two issues, the yield of TFT can be reduced significantly. This paper presents a spice-based simulator, FlexiAnalyzer, for flexible TFT circuits. This simulator performs four types of analysis: yield analysis, aging analysis, performance analysis, and weak-spot analysis. This simulator considers three important effects: (1) threshold voltage variation caused by manufacturing process, (2) threshold voltage shift due to aging effect, and (3) mobility change due to bending effect. Six different OLED drivers using 8um amorphous silicon TFT technology were simulated. Experimental results show significant yield difference among designs. The proposed tool provides solutions for designers to evaluate the performance and yield of flexible TFT circuits.

並列關鍵字

SPICE ； Flexible TFT Circuits ； Circuit Analyzer ； Aging Effect ； Bending Effect

參考文獻

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