中国物理B ›› 2012, Vol. 21 ›› Issue (5): 58201-058201.doi: 10.1088/1674-1056/21/5/058201

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

The light-enhanced NO2 sensing properties of porous silicon gas sensors at room temperature

陈慧卿,胡明,曾晶,王巍丹   

  1. School of Electronics and Information Engineering, Tianjin University, Tianjin 300072, China
  • 收稿日期:2011-10-10 修回日期:2012-04-27 出版日期:2012-04-01 发布日期:2012-04-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60771019 and 60801018) and the Tianjin Key Research Program of Application Foundation and Advanced Technology, China (Grant No. 11JCZDJC15300)

The light-enhanced NO2 sensing properties of porous silicon gas sensors at room temperature

Chen Hui-Qing(陈慧卿), Hu Ming(胡明), Zeng Jing(曾晶), and Wang Wei-Dan(王巍丹)   

  1. School of Electronics and Information Engineering, Tianjin University, Tianjin 300072, China
  • Received:2011-10-10 Revised:2012-04-27 Online:2012-04-01 Published:2012-04-01
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60771019 and 60801018) and the Tianjin Key Research Program of Application Foundation and Advanced Technology, China (Grant No. 11JCZDJC15300)

摘要: The NO2 gas sensing behavior of porous silicon (PS) is studied at room temperature with and without ultraviolet (UV) light radiation. The PS layer is fabricated by electrochemical etching in an HF-based solution on a p+-type silicon substrate. Then, Pt electrodes are deposited on the surface of the PS to obtain the PS gas sensor. The NO2 sensing properties of the PS with different porosities are investigated under UV light radiation at room temperature. The measurement results show that the PS gas sensor has a much higher response sensitivity and faster response--recovery characteristics than NO2 under the illumination. The sensitivity of the PS sample with the largest porosity to 1 ppm NO2 is 9.9 with UV light radiation, while it is 2.4 without UV light radiation. We find that the ability to absorb UV light is enhanced with the increase in porosity. The PS sample with the highest porosity has a larger change than the other samples. Therefore, the effect of UV radiation on the NO2 sensing properties of PS is closely related to the porosity.

关键词: gas sensor, ultraviolet radiation, porous silicon, porosity

Abstract: The NO2 gas sensing behavior of porous silicon (PS) is studied at room temperature with and without ultraviolet (UV) light radiation. The PS layer is fabricated by electrochemical etching in an HF-based solution on a p+-type silicon substrate. Then, Pt electrodes are deposited on the surface of the PS to obtain the PS gas sensor. The NO2 sensing properties of the PS with different porosities are investigated under UV light radiation at room temperature. The measurement results show that the PS gas sensor has a much higher response sensitivity and faster response--recovery characteristics than NO2 under the illumination. The sensitivity of the PS sample with the largest porosity to 1 ppm NO2 is 9.9 with UV light radiation, while it is 2.4 without UV light radiation. We find that the ability to absorb UV light is enhanced with the increase in porosity. The PS sample with the highest porosity has a larger change than the other samples. Therefore, the effect of UV radiation on the NO2 sensing properties of PS is closely related to the porosity.

Key words: gas sensor, ultraviolet radiation, porous silicon, porosity

中图分类号:  (Electrochemical sensors)

  • 82.47.Rs
73.61.Cw (Elemental semiconductors) 72.40.+w (Photoconduction and photovoltaic effects) 73.25.+i (Surface conductivity and carrier phenomena)