有機發光二極體畫素之噴印平整度改善

Layer Flatness Improvement by Inkjet-Printed OLED Pixel

林勁言(Lin, Chin Yen)

指導教授 ： 羅丞曜

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2015年)

摘要

本論文提出一種以第二次噴印改善第一次噴印OLED材料平整度不均問題的方法。此方法以可精確定位的噴印技術將所需材料填補於因咖啡環效應產生之第一次噴印材料凹口內，以期改善電流及發光之分布均勻性。
本研究以積分精算第一次噴印材料之凹口體積，並配合順序、方向、重疊比例及分割區域之優化，達成將此凹口體積縮減73%的成果。本研究除提出以凹口左右兩側為基準之乾膜平整度標準差作為改善之量化驗證外，亦證明以此第二次噴印方法所造成之整體穿透率下降及電阻率上升分別不超過1.5%及15%，暗示了不需以特殊設備、材料及製程步驟改變OLED畫素之親疏水性即可改善乾膜平整度。

關鍵字

二次填墨 ； 凹口狀 ； 有機發光二極體 ； 咖啡環效應 ； 噴印製程

並列摘要

This research proposed a method that compensates the recess of the first OLED layer resulted from wet process by a second inkjet printing. The inkjet printing filled the material to the recess resulted in the first layer because of the coffee ring effects with precise positioning, in order to improve the current distribution and light emitting uniformity.
This research obtained the recess of the first layer by integration and reduced 73% recess volume with sequence, direction, overlap ratio, and segment amount optimizations. This research not only provided a methodology that evaluates the dry-film uniformity by standard deviation between the two peaks of the recess quantitatively, but also proved that the transmittance and the resistivity resulted from this method reduced and increased less than 1.5% and 15%, respectively. These result implied that the dry-film uniformity can be improved without extra facilities, material, and processes for the hydrophilicity and hydrophobicity of OLED.

並列關鍵字

Second Printing ； Recess Volume ； OLED ； Coffee Ring Effect ； Inkjet Printing

參考文獻

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