參錫氧化銦（ITO）薄膜透明電極一直是大部分透明導電電極的主要產品，但是銦元素在地球的含量很少而且ITO本身具有脆性，這會给後來軟性基板上的應用帶來很大的不便。為了取代ITO現在出現許多新一代的透明電極，像是其他的種類的透明導電金屬氧化物例如摻鋁氧化鋅(AZO)或是石墨烯以及金屬奈米線的網絡。因為奈米銀線（Ag NWs）的導電率高、無毒且易於製備等特性，奈米銀線網絡透明電極（Ag NW network TCEs）被認為是最有淺力取代ITO。
我們成功合成Ag NWs並在室温環境下利用高壓力的方式，將Ag NWs network押在含有PMMA薄膜的玻璃上，而且達到93.8%的穿透度和39 Ω/□ 的片電阻，高壓力使得Ag NWs更有效地連接，使得因為Ag NWs network所造成的表面粗糙程度大幅度地被降低的和有效提升導電性質，此外我們成功地展示這種方式可以將Ag NWs network隨意的轉放在任何基板上，在轉移後Ag NWs仍然具有良好導電特性和機械性質，也成功地應用在有機發光二極體元件上並且得到良好的特性，外部量子效率高達19.9%。此外我們也將Ag NWs放在AZO中形成三明治結構的透明電極，並成功應用在軟性的硒化銅銦鎵薄膜太陽能電池（CIGS solar cell）並且在元件的可饒特性測試表現較ITO優秀。

Owing to the scarcity of indium element and the natural brittleness of tin doped indium oxide (ITO), several emerging transparent and conductive electrodes (TCEs) including metal oxides, carbon nanotubes, graphene, metallic nanowire networks and metal grids have been developed recently. One of them is the silver nanowires (Ag NWs) network TCE that can be considered as the most promising candidate for replacing commercial ITO due to their non-toxicity and easy preparation.
We report an Ag NWs TCEs embedded into PMMA by pressing can be used as a high quality TCEs with lower sheet resistance and good transmittance for optoelectronic devices. The sheet resistance (Rsheet) of Ag NWs/PMMA composite TCEs can be remarkably reduced from 36k (Ω/□) to 40 (Ω/□) comparing with the pure Ag NWs network and its transmittance reached to 93.8% (@550 nm). The pressing process, not only greatly improved contact junction between NWs with outstanding reduction of sheet resistance owing to larger and more effective contact areas, but also decreased the surface roughness of the composite transparent electrode, which dominates performances of OLED devices. In addition, we successfully demonstrated an approach to transfer Ag NWs network onto various flexible substrates including PEN, PI and papers. After 10000 bending tests with a curvature radius of 2mm, Ag NWs/PMMA composite electrode on PI and PEN substrates exhibited better mechanical flexibility with low sheet resistances of ~42 (Ω/□) for PI and ~91 (Ω/□) for PEN. By utilizing this Ag NWs TCEs as the anode in ITO-free organic light emitting diodes (OLEDs), promising performance of 85.9 lm W−1 power efficiency and 19.9% external quantum efficiency is demonstrated, compared with the ITO case of 80.1 lm W−1 and 19.2%. Finally, we have demonstrated flexible high conversion efficiency CIGS solar cells with a hybrid TCE of AZO/Ag NWs/AZO (called AAA films). Based on the results of bending test, the flexible CIGS cell with AAA films also exhibited better device performance nearly without decay.

摘要 I
Abstract II
致謝 IV
Table of Contents V
Figure Caption VII
Table Caption XI
Chapter 1 Introduction 1
1.1 1.1 Preface 1
Chapter 2 Literature Rewiew 2
2.1 2.1 Transparent Electrodes 2
2.1.1 Transparent Conductive Oxide 2
2.1.2 Metal Nanowire Network Electrodes 4
2.1.3 Graphene 6
Chapter 3 Experimental Techniques 12
3.1 3.1 Material and electrical analysis 12
3.1.1 X-ray diffractometer 12
3.1.2 Field-emission scanning electron microscopy 12
3.1.3 Field-emission transmission electron microscopy 13
3.1.4 Atomic Force Microscope 15
3.1.5 Raman 16
3.1.6 Keithley 4200 semiconductor analyzer 16
Chapter 4 Silver Nanowires Network Transparency Electrodes 18
4.1 4.1 Motivation 18
4.2 4.2 Experimental Procedures 19
4.2.1 Synthesis of Silver Nanowires 19
4.2.2 Characteristics of Silver Nanowire 20
4.2.3 Fabrication of Ag NW TCEs 23
4.2.4 Results of Ag NW TCEs 26
4.2.5 Bending Test 33
4.3 4.3 Applications 35
4.3.1 Organic Light-Emitting Diodes 35
4.3.2 AZO/Ag NWs/AZO Sandwich Structure Transparent Electrodes Apply on CIGS Solar Cell 40
Chapter 5 Summary 46
Reference 47

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