脉冲激光溅射沉积WO_3气敏膜

WO_3 Gas Sensor Films Deposited by Pulsed Laser Deposition

本文研究了脉冲激光溅射镀膜技术沉积WO_3基片在室温下,沉积的WO_3膜部分晶化并部分还原.经热处理,在450℃左右膜层开始晶化,最后形成三斜晶系的WO_3晶化后颗粒在几十到几百纳米之间.本技术沉积的WO_3膜对NO_2气体有非常好的气敏性能,可检测0.1×10^(-6)量级的NO_2气体.WO_3膜的灵敏度随温度降低而增大,但同时响应时间和恢复时间增长.同其它制备技术相比,本技术沉积的WO_3膜显著提高了响应性能:响应时间和恢复时间,它们分别为30_s和70_s.

Abstract This article studied the WO3 thin films deposited by pulsed laser depositiontechnique. The fresh films were partially crystallized and partially reduced when the sub-strates were kept at room temperature. When being annealed, the films started to crys-talline at 450℃, and formed triclinic structure at last. The crystallites were between tensto hundreds nm. The WO3 films deposited by this technique showed good sensitivity toNO2 and that sub-ppm NO2 could be detected. Sensitivity increased when temperature waslowered, and the responsc and recovery times were prolonged. Compared with other tech-niques, pulsed laser deposited WO3 increased the response speed significantly, the re-sponse time and recovery time can be 30 s and 70 s respectively.