Negative Effects of Annealed Seed Layer on the Performance of ZnO-Nanorods Based Nitric Oxide Gas Sensor

Sensors

Pragya Singh¹  Jinn P. Chu¹  Hsiao-Wen Zan²  Li-Lun Hu²  Firman Mangasa Simanjuntak³  Tseung-Yuen Tseng³ 

[1] Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan;Department of Photonics and Institute of Electro-Optical Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan;Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan;

关键词: annealing;    ZnO;    nanorods;    thin-film;    gas sensor;    metal-oxide-semiconductor;   

DOI  :  10.3390/s22010390

来源: DOAJ

【 摘 要 】

Nitric oxide (NO) is a toxic gas, which is dangerous for human health and causes many respiratory infections, poisoning, and lung damage. In this work, we have successfully grown ZnO nanorod film on annealed ZnO seed layer in different ambient temperatures, and the morphology of the nanorods sensing layer that affects the gas sensing response to nitric oxide (NO) gas were investigated. To acknowledge the effect of annealing treatment, the devices were fabricated with annealed seed layers in air and argon ambient at 300 °C and 500 °C for 1 h. To simulate a vertical device structure, a silver nanowire electrode covered in ZnO nanorod film was placed onto the hydrothermal grown ZnO nanorod film. We found that annealing treatment changes the seed layer’s grain size and defect concentration and is responsible for this phenomenon. The I–V and gas sensing characteristics were dependent on the oxygen defects concentration and porosity of nanorods to react with the target gas. The resulting as-deposited ZnO seed layer shows better sensing response than that annealed in an air and argon environment due to the nanorod morphology and variation in oxygen defect concentration. At room temperature, the devices show good sensing response to NO concentration of 10 ppb and up to 100 ppb. Shortly, these results can be beneficial in the NO breath detection for patients with chronic inflammatory airway disease, such as asthma.

【 授权许可】

Unknown