氧化鎢（Tungsten oxide,WO3）薄膜具有化學穩定性及數個過渡相，適當的控制氧化鎢的化學劑量比與組織、結構等，可以有利於提昇薄膜的機械性質，且有研究指出氧化鎢薄膜具抗磨耗特性，在機械工業上具有應用潛力。本研究利用電沉積法來製備氧化鎢薄膜。為了完整探討成長薄膜之製程、特性與應用，本研究首先將進行製程參數探討與特性分析，使用電沈積法分別在氧化銦錫 (ITO) 導電玻璃以及SKD-11工具鋼上沉積氧化鎢薄膜，經由控制沉積時間及熱處理條件獲得不同膜厚、表面粗糙度以及薄膜結晶性等物理特性，以求出薄膜製程的最佳化參數。接著再以SEM、XRD、奈米壓痕機、磨耗試驗機等儀器對薄膜進行表面形貌觀察、結晶分析、接觸角量測、奈米壓痕測試、磨耗實驗等量測分析，並針對薄膜的表面粗糙度、結晶性、硬度、楊氏係數與抗磨耗等特性探討。實驗結果顯示，熱處理溫度為影響氧化鎢薄膜結晶性的主要因素；以ITO為基板沉積的氧化鎢薄膜，在經過350℃退火後開始轉變為結晶相，並在經過500℃以上退火後出現明顯之氧化鎢（200）立方晶特徵峰；而以SKD-11為基板沉積的氧化鎢薄膜，在未經退火及400℃以下的熱處理條件，薄膜呈非晶態；在經過500℃以上的熱處理條件後結晶轉變形成立方晶結構。結晶性則影響了薄膜的表面粗糙度、硬度、楊氏係數等，非晶型態的薄膜表面並未生成明顯的晶粒結構，所以表粗較低，而經過熱處理之薄膜因晶粒逐漸成長而具有較大的表面粗糙度；而經過500℃以上熱處理後，氧化鎢薄膜具有規則排列之晶格結構，所以表面粗糙度反而些許下降；並從奈米壓痕實驗中可得知，經過熱處理後的氧化鎢薄膜，具有較佳的硬度及楊氏係數；而硬度及楊氏係數則會間接影響氧化鎢薄膜的耐磨耗性能，從磨耗實驗數據得知本研究之氧化鎢薄膜與單純母材試片相比，確實具有一定的抗磨耗特性，且其中經過熱處理的薄膜抗磨耗特性更是優於其他參數。綜合以上所述，本研究之電沉積氧化鎢薄膜經過適當的熱處理後，各項性質如硬度、楊氏係數及耐磨耗性等皆會提升。

Tungsten oxide (WO3), a type of transition metal oxides, is well recognized by its stable chemical property and transition phases for many applications namely photocatalysis, sensing, and anti-abrasion coating. The excellent mechanical and anti-wear properties of tungsten oxide thin film could also improve the tribology behavior for many machinery applications. However, to fabricate the tungsten oxide thin film for further application requires sophisticate machinery and expertise. Although several methods have been adapted for tungsten oxide thin film production including evaporation, sol-gel, chemical vapor deposition, RF sputtering as well as DC reactive magnetron sputtering, enhanced electrodepositing approach proposed below may strengthen this technology even more. Benefit from the electrodepositing process, the tungsten oxide thin films improve their photocatalysis, electrochromic and anti-abrasion property. Moreover, the advantages of electrodeposited technology lie in its fast preparation speed, low cost, no vacuum-environment required, well suited for coating of large area, and its potential for continuous production. It also sustains low temperature for the rapid preparation of those required coating layers. To investigate the progress, characteristic, and application of WO3 thin film, this study is to formulate thin films on ITO glass and SKD-11 tool steel substrate by using electrodeposited process. Furthermore, the crystalline and nanoindentation properties of thin films have been analyzed when annealing under various temperatures. Experimental results show that the films are dense and have good adhesion with ITO and SKD-11 substrate by appropriately controlling processing parameters. The WO3 thin films became crystalline after annealing at the temperature above 500℃. Consequently, the annealed WO3 thin film exhibited better mechanical properties than the as-deposited film, including hardness and young’s modulus. At the same time, the anti- abrasion properties of the film are also improved.

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