(東北大學(xué) 資源與土木工程學(xué)院，沈陽(yáng) 110819)
摘 要: 采用直流反應(yīng)磁控濺射法，在不同的基片溫度條件下制備出具有不同微觀(guān)結(jié)構(gòu)的WO3薄膜，探討這些薄膜作為氣敏材料對(duì)NO2氣體的氣敏特性。WO3薄膜的晶體結(jié)構(gòu)、表面及斷面形貌分別采用X射線(xiàn)衍射和掃描電子顯微鏡進(jìn)行表征。結(jié)果表明：隨著基片溫度的升高，具有單斜晶WO3結(jié)構(gòu)薄膜的(200)衍射峰強(qiáng)度逐漸增強(qiáng)，薄膜由低基片溫度(-75 ℃)的納米粉體、過(guò)渡到中間基片溫度(-50~300 ℃)的納米薄膜、直至高基片溫度(500 ℃)的納米棒組成。所有WO3薄膜均在200 ℃的工作溫度下獲得對(duì)NO2氣體的最大靈敏度。在相同的檢測(cè)條件下，氣體靈敏度隨著基片溫度的減小和NO2氣體濃度(體積分?jǐn)?shù))的增加而增大。
關(guān)鍵字: 三氧化鎢；薄膜；基片溫度；二氧化氮；氣體傳感器
（School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China）
Abstract:WO3 thin films with various microstructures were deposited at different substrate temperatures using DC reactive magnetron sputtering. NO2 sensing properties of these WO3 thin films as the sensing materials were investigated. The crystal structure and morphology of these WO3 thin films were characterized by X-ray diffractometry and scanning electron microscopy. The results show that, as the substrate temperature increases, the intensity of (200) diffraction peak gradually increases for these films composed of monoclinic WO3 structure. The morphology changes from nanopowders at a low substrate temperature of -75 ℃, to nanofilms at the substrate temperature range of -50-300 ℃, finally to nanorods at a high substrate temperature of 500 ℃. All the film sensors show the highest NO2 response at an operating temperature of 200 ℃. Under the same conditions, the response increases with the decrease of substrate temperature and the increase of NO2 concentration (volume fraction).
Key words: tungsten oxide; thin film; substrate temperature; nitrogen dioxide; gas sensor
