- 學位論文
探討多層透明導電薄膜AZO/Ag/AZO在光電元件之應用
Characterization of Multilayer AZO/Ag /AZO Transparent Conducting Thin Film for Opto-Electronics Device Applications
摘要
透明導電膜 ( transparent conducting films ) 指的是在可見光範圍內具有高穿透率，且具有良好導電性之薄膜。由於具特別的光性質及電性質，可應用在諸多領域。 本研究利用RF磁控射頻濺鍍法沉積氧化鋅摻鋁 (AZO) 透明導電薄膜，藉由改變濺鍍條件中之射頻功率、基板溫度、工作壓力等參數，探討製程參數對於沉積單層AZO薄膜之光學及導電性的影響，藉由其分析結果定義出最佳製程條件之AZO透明導電膜。 在單層AZO薄膜的特性定出後，同樣以濺鍍的方式製備AZO/Ag/AZO三層結構之透明導電膜於玻璃基板上，首先將上下兩層之AZO薄膜定為相同的厚度(30 nm)，以電子束蒸鍍成長奈米厚度(5nm ~ 15nm)之Ag膜，探討Ag厚度變化對於其光學及導電性的影響。 在薄膜的物性研究方面，藉由FE-SEM和AFM觀察薄膜之微結構變化與表面粗糙度；在光學性質方面，藉由紫外線可見光光譜儀，分析Ag中間層不同的厚度薄膜之光學穿透率；在電學性質方面，使用霍爾量測其載子濃度與電子遷移率。 由實驗結果得知， FE-SEM與AFM分析顯示中間層Ag在不同厚度之薄膜表面微結構有不同的變化；在Ag厚度於10 nm時，薄膜在可見光區最大逹到91.89 % 之透光度；載子濃度約為8.563 × 10-21 cm-3；遷移率約為9.265 cm2/V-s；低電阻率約為3.71 × 10-4 Ω-cm。 綜合以上實驗結果得知， Ag層厚度對AZO薄膜晶體結構與光電特性有很大的影響，適當的銀層會提升其特性。該研究的AZO/Ag/AZO多層薄膜透明導電膜適合作為透明電極的應用。
並列摘要
Transparent conducting films has high properties of transmittance and conductance in the visible range. Because of its special optical and electrical properties, it is used for many application. We report in this paper our study on Aluminum -doped ZnO (AZO) thin films and three-layered thin films, in which a Ag thin film is sandwiched in between two AZO thin films. First of all, AZO thin films were deposited on glass substrates using an RF magnetron sputter deposition method. The optical and electrical properties of AZO thin films with different deposition parameters, including sputtering power, T-S distance, working pressure and oxygen pressure, were investigated. According to the above analysis the best deposition parameters of AZO thin film can be determined. And then a three-layered thin film (AZO/Ag/AZO) was grown on the glass substrate to enhance the electrical conductivity. The Ag thin film was deposited between a fixed AZO thin film (5 ~ 15 nm) using a E-Beam deposition method. The different thickness of Ag thin film were applied. All the films obtained were characterized for the electrical and optical properties. The variation of the properties with Ag film thickness was investigated. For the physical property analysis of the AZO thin films, the microstructure and roughness of the AZO thin films which had been interlayer with different Ag thickness were measured by field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM), respectively. For the optical property analysis of the AZO thin films, the transmittance and reflectivity of the AZO thin films which had been interlayer with different Ag thickness were measured by the ultraviolet-visible spectrophotometer (UV-VIS). For the electrical property analysis of the AZO thin films, the carrier concentration and the carrier mobility were measured by hall effect measurement system . In the experiment results,the FE-SEM and AFM analysis present the variation of the surface microstructure is as a function of Ag layer. In the transmittance part, the AZO thin films interlayer with Ag thickness of 10 nm is over 91.89 % of maximum transmittance in the visible part of the spectra (300 ~ 800 nm): the carrier concentration of 8.563 × 10-21 cm-3；mobility of 9.265 cm2/V-s；low resistivity of 3.71 × 10-4 Ω-cm. Due to the above results, the appropriate Ag layer can enhance the crystal structure, optics and electricity properties of AZO thin films. The AZO/Ag/AZO multilayer thin film is suitable as transparent conductive component for transparent electronics.