氧化鎢摻雜氧化鈦奈米線應用於場發射及氣體感測特性之研究

本研究係利用直流磁控濺鍍配合紅外線加熱爐退火處理，並分別探討在不同的退火溫度(600~700℃)、退火時間(1~2hr)、退火氣氛(Vacuum、Ar:O2=400:1)以及鈦的摻雜量(0~2.3wt%)對生成奈米材料的成份、結構及形貌影響之研究，其並針對氧化鎢及氧化鎢摻雜氧化鈦奈米材料的場發射與氣體感測特性進行分析與探討。研究中發現，氧化鎢奈米線隨著退火溫度，薄膜會開始成核成長逐漸轉變為一維奈米結構。但隨退火時間增加，一維奈米結構的長度逐漸縮短，且寬度有增長之趨勢。然而，鈦元素的添加提高了奈米線生成溫度，但有助於一維氧化鎢摻雜氧化鈦奈米材料長寬比提高。微結構分析得知，本實驗所製備的氧化鎢及氧化鎢摻雜氧化鈦奈米線為W18O49相態，晶格成長方向是延著(010)晶面成長，並由HRTEM的結果得知晶格間距為0.378nm，與XRD及GI-XRD結果相符。成長機制可透過固-固相(S-S)法解釋。本研究製備之氧化鎢及氧化鎢摻雜氧化鈦奈米線具有優異的場發射起始電場與增強因子，分別為3.06 V/μm、3773和1.46 V/μm、6962和37214，且符合F-N原理的能障穿隧行為。於氣體感測結果顯示，於最佳工作溫度200℃下對不同濃度(1~20ppm)之NO2氣體，其氧化鎢摻雜氧化鈦奈米線具有最佳感測性質，且隨著濃度的增加靈敏度(5.42至7.61)也會呈現線性成長。

關鍵字

磁控濺鍍；熱退火；氧化鎢；氧化鈦；場發射；氣體感測

並列摘要

In this study, the titanium oxide doped nanowires of tungsten oxide were prepared using DC magnetron sputtering, followed by annealing treatment. We adjusted various fabricated parameters such as the annealing temperature (600-700 °C)、annealing duration (1-2 hr) 、annealing atmosphere (Vacuum and Ar:O2=400:1) and Titanium doped (0~2.3wt%) to investigate their impact on the morphology, phase, microstructure and for field emission and sensing. We observed that the tungsten thin films are synthesized to transform into an one-dimensional structure of tungsten oxide with annealing treatment of 600~700℃.The length of nanowires gradually shortened with an increases in the annealing duration, but the width of nanowires had growth trend. However, doped Ti would enhance the formation temperature of nanowires, but helped the nanowires aspect ratio increased. The results of microstructure analysis indicate that the titanium oxide doped nanonanowires of tungsten oxide and tungsten oxide nanowires present W18O49 phase with (010) growth plane. After HRTEM analysis, the d-spacing of (010) plane is 0.378 nm, which can be attributed to the Solid-Solid transformative growth mechanism. In this study, the titanium oxide doped nanowires of tungsten oxide and nanowires of tungsten oxide showed better field-emssion properties. The turn-on field and field enhancement factor of around 3.06 V/μm、3773 and 1.46 V/μm 、6962 and 37214, respectively. It could be emerged as a promising candidate for field emission application on account of its specialized characteristics. In gas sensing results the titanium oxide doped nanowires of tungsten oxide in optimum working temperature of 200 ℃ under different concentrations (1 ~ 20ppm) has optimal NO2 gas properties, and sensitivity (5.42 to 7.61)increased with the concentration also showed a linear growth.

並列關鍵字

Magnetron Sputtering ； Annealing ； Tungsten Oxide ； Titanium Oxide ； Field Emission ； Gas sensing

參考文獻

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氧化鎢摻雜氧化鈦奈米線應用於場發射及氣體感測特性之研究

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