觸控面板之高片電阻透明導電膜導電機制研究

Research of the mechanism for transparent conductive oxide films with high sheet resistance applied in touch panel

劉金讓(Jin-Rang Liu)

指導教授 ： 李正中 ； 陳昇暉

國立中央大學/理學院/光電科學研究所/碩士(2011年)

摘要

科技日進千里的發展讓人們對生活品質的要求愈來愈高，近年來蓬勃發展的觸控市場，如觸控式手機、iPad、平板電腦、電子書…等，這些產品內都有著透明導電薄膜的應用。不同科技產品所需要的片電阻範圍不同，例如觸控面板的片電阻要求較高約在400Ω/□左右，以免片電阻過低產生誤觸感應的情況，而較高的片電阻可藉由導電膜製鍍較薄的厚度來得到，此外，薄化ITO膜亦可提高業界材料成本競爭力與出貨效率。
本論文利用磁控濺鍍法在室溫下製鍍ITO薄膜，隨後進行200℃~450℃的大氣退火，研究分析20nm以下的極薄層與一般膜厚退火導電機制差異，並探討不同靶材摻雜比例的影響。
以90% In2O3 + 10% SnO2靶材室溫製鍍膜厚20m的ITO膜片電阻為265Ω/□，在200℃與450℃的大氣退火之後分別有588Ω/□與572Ω/□的片電阻值，並且連同玻璃基板的總可見光平均穿透率在退火前後皆在85%以上。

關鍵字

觸控面板 ； 透明導電膜 ； ITO ； 氧化銦錫 ； 超薄

並列摘要

ITO films have been deposited by DC pulse magnetron sputtering on glass (B270) at room temperature. The Ssheet resistance and resistivity were measured by Hall system and shownwere decreased when film thickness increased. Resistivity The resistivities of the as-deposited films with thickness 6 nm and 28 nm were 1.43*10-3 Ω-cm and 4.72*10-4 Ω-cm, respectivelyas deposited. As deposition, Tthe ultrathin ITO films are were amorphous. as deposited wAnd ithile the films became polycrystalline with of very small grains size when the film thickness was increased to about 71nm. And this is tThe reason is that makesthe less scattering grain boundary scattering tocauses the lower the resistivity.

The present work has shown that the properties of ultrathin ITO films deposited on glass exhibit changes with increasing thickness. This paper is focus on the ultrathin ITO film electrical properties change after atmosphere annealing process. for those film thicknesses below 28nm. ITO film with 6 nm thickness was still amorphous. Its carrier concentration after 200"℃" atmosphere annealing was lower than before annealing. When the film was annealing to 350"℃" under atmosphere, it became crystallization and showed a XRD peak at (2 2 2) with grain size 5.4nm. And the carrier concentration got sharply increased. Combining the relationship between the resistivity and the crystalline structure of ITO film, we found when the crystalline was beginning, the conductivity will be increased. This is because the tin become effective dopant and replace indium rather interstitial dopant. The best resistivity is 8.62*10-4 Ω-cm and the transmittance with substrate was greater than 90%, when the 6-nm-thickness ITO film was annealed at 450"℃" under atmosphere.

並列關鍵字

ultrathin ； indium tin oxide ； ITO ； TCO ； touch panel

參考文獻

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