射頻磁控濺鍍沉積氧化鋅鎵透明導電膜於可撓性塑膠基板之研究

Transparent conducting GZO films grown on flexible substrates by magnetron sputtering

李威憲

指導教授 ： 周明

國立臺灣師範大學/科技學院/工業教育學系/碩士(2011年)

摘要

所謂透明導電膜(TCO)是指在可見光範圍 (波長380-760nm)，具有高光穿透率(＞80％)和低電阻率(≦1×10-3 -cm)的薄膜，其被廣泛應用於各種科技產品，如：透明電極、太陽能電池、氣體感測器，壓電變換裝置和表面聲波器件。近年來，氧化鋅(ZnO)被應用在TCO上，由於它具有多樣的優點，在全球各相關產業受到了關注，例如ZnO的材質、與ITO和SnO2薄膜比較之下，不具有毒性，且成本低廉。 可撓性塑膠基材上濺鍍透明導電膜，相較於玻璃基材有更多的優點，如：質量較輕，體積較小，耐衝擊且不易碎。在本研究中，使用磁控濺鍍並利用氧化鋅鎵(GZO)製備透明導電膜(Ga2O3比例是大约3 wt.%)。本文使用GZO薄膜的最佳參數化設計與灰關聯分析結合的田口法。藉由田口法參數設計， 實驗流程為L9正交排列組合。其中可變的參數(RF功率、濺鍍壓力、基材溫度和沉積時間)的作用對GZO薄膜的光、電性質，結構與表現形態進行分析。 在經由灰關聯理論的驗證分析，得到一組灰關聯實驗參數改善78.84%的電阻率，但是光穿透率則稍稍降低。實驗結果分別顯示濺鍍功率和濺鍍壓力是在實驗過程中最重要因子。實驗結果證明，灰關聯實驗參數能夠確實的提升透明導電膜的性質。

關鍵字

氧化鋅 ； 磁控濺鍍 ； 透明導電膜 ； 灰關聯理論

並列摘要

Transparent conducting oxide (TCO) film with optical transmission of more than 80% in the visible region and resistivity of less than 10-3 -cm is used in various technological fields such as transparent electrodes, solar cells, gas sensors, piezoelectric transducers and surface acoustic wave devices. Recently, zinc oxide (ZnO), an alternative TCO material, has received considerable attention due to its various advantages, such as its abundance in nature, non-toxicity and good stability in hydrogen plasma processes as compared to ITO and SnO2 films.
Transparent conducting films deposited on polymer substrates have many merits compared with those deposited on conventional glass substrate, such as their light weight, small volume, impact resistance, ease of transport and flexibility. In this study, gallium-doped zinc oxide (GZO) transparent conductive thin films were deposited on inexpensive polyethylene terephthalate (PET) substrates by radio frequency (rf) magnetron sputtering using the GZO ceramic target (the Ga2O3 contents are approximately 3 wt.%). This paper presents an effective method for the optimization of the deposition process parameters of GZO thin films by using the Taguchi method combined with the grey relational analysis. Based on the Taguchi quality design concept, an L9 orthogonal array table was chosen for the experiments.
The effects of various process parameters (RF power, sputtering pressure, substrates temperature and deposition time) on electrical, structural, morphological and optical properties of GZO films were investigated. In the confirmation runs, when using grey relational analysis, improvement of 78.84% was obtained in electrical resistivity, but in visible range transmittance was decreased slightly. The experimental results revealed that RF power and sputtering pressure were the most influential factor on the deposition process, respectively. Experimental results are provided to illustrate the effectiveness of this approach.

並列關鍵字

zinc oxide ； magnetron sputtering ； transparent conductive films ； grey relational analysis

參考文獻

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