以電沉積法製作大面積氧化鋅薄膜與奈米柱陣列

Large Area ZnO Films and Nanorod Arrays by Electrodeposition

ZnO 薄膜由於具許多優良性質，如壓電、導電及光發射等特性，因此在感測器、表面聲波元件、透明導電膜及螢光材料等許多方面引起很大注意力。在本實驗中，我們使用定電位與定電流兩種電沉積方式在ITO 玻璃上生長ZnO薄膜，以研究其不同之沉積機制。同時，藉由XRD、SEM、EPMA、EDS 和UV-Visible 等分析儀器，觀察量測電沉積ZnO 之晶體結構、表面形態及光穿透率。由XRD 可得知優選方位為 （002），其繞射峰強度會隨沉積時間和酸鹼值增加而增大。此外，SEM 顯示電沉積ZnO 為六角柱狀晶粒，其c 軸生長方向是垂直於底材。實驗結果亦顯示，在定電位沉積模式下，所沉積的ZnO 薄膜，結晶顆粒較小，均勻度和光穿透率較高；光穿透率在700 nm時約為90％。同時我們也利用AAO 模板電沉積ZnO 奈米柱，利用SEM 及AFM 進行觀察其成長情形。

Zinc oxide (ZnO) films have attracted much attention for use assensors, surface acoustic wave elements, transparent conductive film, andfluorescent materials because of their piezoelectric effects, conductiveeffects, light emission effects, and so on. In this study, two differentelectrodeposition methods (constant-potential and constant-current) havebeen applied to investigate the formation mechanism of ZnO on indium tinoxide (ITO). The crystallinity, surface morphology, composition andtransmittance of the deposition ZnO on ITO substrate were investigated byX-ray diffraction (XRD), scanning electron microscopy (SEM), electronprobe X-ray microanalyzer (EPMA), and UV-Visible Spectrometer. XRDshows a preferential orientation (002) that increases strongly, in direct ratiowith deposition time and pH value. Additionally, SEM micrographs showthe ZnO electrodeposits consisted of columnar grains, which grew with c axis perpendicular to the substrate. Furthermore, experimental resultsindicate that smaller grains, uniformity and higher transmittance of ZnOfilms result from electrodeposition under constant-potential. Thetransmittance at 700 nm for ZnO thin films prepared by electrochemicaldeposition approached 90%. In this paper, we also report on the structure ofelectrodeposited ZnO nanorods on anodized aluminum oxide (AAO)template. The morphology examination of the ZnO/AAO nanorods werecarried out by SEM and AFM.