(东北大学 资源与土木工程学院，沈阳 110819)
摘 要: 采用直流反应磁控溅射法，在不同的基片温度条件下制备出具有不同微观结构的WO3薄膜，探讨这些薄膜作为气敏材料对NO2气体的气敏特性。WO3薄膜的晶体结构、表面及断面形貌分别采用X射线衍射和扫描电子显微镜进行表征。结果表明：随着基片温度的升高，具有单斜晶WO3结构薄膜的(200)衍射峰强度逐渐增强，薄膜由低基片温度(-75 ℃)的纳米粉体、过渡到中间基片温度(-50~300 ℃)的纳米薄膜、直至高基片温度(500 ℃)的纳米棒组成。所有WO3薄膜均在200 ℃的工作温度下获得对NO2气体的最大灵敏度。在相同的检测条件下，气体灵敏度随着基片温度的减小和NO2气体浓度(体积分数)的增加而增大。
关键字: 三氧化钨；薄膜；基片温度；二氧化氮；气体传感器
（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
