Filipovic Lado, Selberherr Siegfried
Institute for Microelectronics, Technische Universität Wien, Gußhausstraße 27-29/E360 Wien, Austria.
Sensors (Basel). 2015 Mar 25;15(4):7206-27. doi: 10.3390/s150407206.
The integration of gas sensor components into smart phones, tablets and wrist watches will revolutionize the environmental health and safety industry by providing individuals the ability to detect harmful chemicals and pollutants in the environment using always-on hand-held or wearable devices. Metal oxide gas sensors rely on changes in their electrical conductance due to the interaction of the oxide with a surrounding gas. These sensors have been extensively studied in the hopes that they will provide full gas sensing functionality with CMOS integrability. The performance of several metal oxide materials, such as tin oxide (SnO2), zinc oxide (ZnO), indium oxide (In2O3) and indium-tin-oxide (ITO), are studied for the detection of various harmful or toxic cases. Due to the need for these films to be heated to temperatures between 250°C and 550°C during operation in order to increase their sensing functionality, a considerable degradation of the film can result. The stress generation during thin film deposition and the thermo-mechanical stress that arises during post-deposition cooling is analyzed through simulations. A tin oxide thin film is deposited using the efficient and economical spray pyrolysis technique, which involves three steps: the atomization of the precursor solution, the transport of the aerosol droplets towards the wafer and the decomposition of the precursor at or near the substrate resulting in film growth. The details of this technique and a simulation methodology are presented. The dependence of the deposition technique on the sensor performance is also discussed.
将气体传感器组件集成到智能手机、平板电脑和手表中，将通过为个人提供使用随时可用的手持或可穿戴设备检测环境中有害化学物质和污染物的能力，彻底改变环境卫生与安全行业。金属氧化物气体传感器依靠氧化物与周围气体相互作用导致其电导率发生变化来工作。人们对这些传感器进行了广泛研究，希望它们能具备完整的气体传感功能并可与互补金属氧化物半导体（CMOS）集成。研究了几种金属氧化物材料的性能，如氧化锡（SnO2）、氧化锌（ZnO）、氧化铟（In2O3）和铟锡氧化物（ITO），用于检测各种有害或有毒情况。由于在运行过程中需要将这些薄膜加热到250°C至550°C之间的温度以增强其传感功能，可能会导致薄膜出现相当程度的降解。通过模拟分析了薄膜沉积过程中产生的应力以及沉积后冷却过程中出现的热机械应力。使用高效且经济的喷雾热解技术沉积氧化锡薄膜，该技术包括三个步骤：前驱体溶液的雾化、气溶胶液滴向晶圆的传输以及前驱体在衬底处或附近的分解从而导致薄膜生长。介绍了该技术的细节和一种模拟方法。还讨论了沉积技术对传感器性能的影响。
