以高頻電漿輔助化學氣相沉積法製備類鑽碳薄膜之研究

Fabrication of DLC films by Very High Frequency Plasma Enhanced Chemical Vapor Deposition

張峻偉(Chun-Wei Chang)

指導教授 ： 徐開鴻

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2010年)

摘要

有機發光二極體 (Organic Light Emitting Diode, OLED) 因具有低操作電壓、反應快、高效率、高亮度、自發光、高對比、低耗電以及低溫製程等特性，遠遠超越LCD，被認為是最有可能取代LCD成為下一世代平面顯示器。然而，OLED內部的高分子有機材料對於氧氣及水氣相當敏感，容易因水氧氣的侵入而導致內部元件的衰退，因此，本研究於軟性透明高分子基板─聚碳酸酯(Polycarbonate,PC)上沉積單層阻水層，阻水層材料選用類鑽碳薄膜，來達到阻絕水氣的功能。
本研究以高頻電漿輔助化學氣相沉積法(VHF-PECVD)沉積類鑽碳薄膜，當製程壓力下降時，薄膜沉積速率會變快，膜越厚；而氣體流量比CH4:H2會隨著氫氣比例增加而導致薄膜沉積速率下降，膜越薄。所以在壓力0.04 torr 、CH4:H2=1:1時，有最快沉積速率35 nm/min。
類鑽碳薄膜的阻絕水氣能力也相當好，在壓力0.2 torr、氣體流量比CH4:H2=1:1時，擁有最佳的水氣穿透率(WVTR) 2x10-4 g/m2/day；可見光穿透率經UV/VIS分析後也有高達約85%。因此，利用VHF-PECVD所製備的含氫類鑽碳薄膜在阻水能力方面以及光學性質方面都相當良好，是足以作為未來OLED氣體阻障層所使用的。

關鍵字

類鑽碳 ； 聚碳酸酯 ； 有機發光二極體 ； 氣體阻障層 ； 可撓性 ； 高頻電漿輔助化學氣相沉積法

並列摘要

OLED (Organic Light Emitting Diode) has overtaken LCD because of its low operating voltage, fast response, high efficiency, high brightness, self-illumination, high contrast, low energy consumption and low temperature process. It will be the next generation main FPD. However, the organic material in OLED are sensitive to water vapor and oxygen. An invasion of water vapor and oxygen will cause declination of OLED. So we have to deposit a thin film of DLC regarded as a gas barrier on polymer substrate to reduce the water permeation.
In this study, VHF-PECVD ( Very High Frequency Plasma Enhanced Chemical Vapor Deposition ) was used to deposit DLC films. Decrease of working pressure is proportional to deposition rate. Inversely, deposition rate will reduce when H2 is increasing for the gas flow ratio CH4:H2. Therefore, we could have the best deposition rate 35nm/min under the circumstance of 0.04 torr、CH4:H2=1:1.
The WVTR of DLC films is 2x10-4 g/m2/day at 0.2 torr、CH4:H2=1:1 and visible light transmittance is about 85%. DLC:H films by VHF-PECVD have a nice gas barrier property and optical property that can be an application for OLED in the future.

並列關鍵字

DLC ； polycarbonate ； OLED ； Gas barrier ； flexible ； VHF-PECVD

參考文獻

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