CFR 법에 의한 산화아연 박막의 제조 및 황 화합물 검출을 위한 전기적 특성

Preparation of Zinc Oxide Thin Film by CFR Method and its Electrical Property for Detection of Sulfur Compounds

  • 이선이 (영남대학교 디스플레이화학공학부 국가지정연구실) ;
  • 박노국 (영남대학교 청정기술연구소) ;
  • 윤석훈 (영남대학교 디스플레이화학공학부 국가지정연구실) ;
  • 이태진 (영남대학교 디스플레이화학공학부 국가지정연구실)
  • Lee, Sun Yi (School of Chemical Engineering and Technology, Yeungnam University) ;
  • Park, No-Kuk (Institute of Clean Technology, Yeungnam University) ;
  • Yoon, Suk Hoon (School of Chemical Engineering and Technology, Yeungnam University) ;
  • Lee, Tae Jin (School of Chemical Engineering and Technology, Yeungnam University)
  • 투고 : 2009.12.04
  • 심사 : 2010.01.31
  • 발행 : 2010.04.30

초록

본 연구에서는 반도체식 가스센서 재료로서 활용 가능한 ZnO 박막을 Continuous Flow Reaction(CFR) 방법으로 실리콘 기판 위에 성장시켰다. 또한 전구물질로 사용한 zinc acetate의 농도에 따른 산화아연 박막의 성장특성과 이들의 전기적 특성이 조사되었다. 산화아연 박막 제조는 0.005~0.02 M의 zinc acetate 농도에서 수행되었다. 산화아연 박막을 구성하고 있는 ZnO의 입자크기는 농도가 증가할수록 증가되었으며, 박막의 두께도 함께 증가되었다. CFR 법에 의한 산화아연 박막의 성장속도는 전구물질의 농도에 비례적으로 의존되는 것을 확인하였으며, 균일한 박막을 제조하기 위한 전구물질의 최적 농도는 0.01 M이였다. 한편, 전구물질의 농도를 달리하여 제조된 산화아연 박막의 전압에 대한 전류를 I-V 측정기로 측정한 결과, 박막의 두께가 증가될수록 높은 전류가 흘렀다. 그러므로 산화아연 박막의 전류를 전구물질의 농도변화로 조절할 수 있다. 또한 산화아연 박막을 $300^{\circ}C$에서 5 min 동안 $500ppmv\;H_2S$에 노출시킨 결과, 전압에 대한 전류값이 낮아졌다. 이와 같이 산화아연의 전기적 특성은 가스센서로 응용할 수 있는 가능성을 확인시켜 주는 결과라 할 수 있다.

The zinc oxide thin film, which can be applied as the gas sensor of a semiconductor type, was grown on the silicon substrate by CFR(continuous flow reaction) method in this study. The growth property and the electrical property of the zinc oxide thin films synthesized by CFR method were also investigated. Zinc acetate solutions of 0.005~0.02 M were used as the precursor for the preparation of zinc oxide thin films. The size of ZnO particles consisted on the zinc oxide thin film increased not only with increasing concentration of precursor, but also the thickness of thin film increased. The growth rate of zinc oxide thin film by CFR method was proportionably depend on the concentration of precursor and the uniform ZnO thin film was prepared when zinc acetate of 0.01 M is used as the precursor. The charged currents on the zinc oxide thin films were obtained as its electrical property by I-V meter, and increased agree with increasing the thickness of zinc oxide thin film. Thus, it was concluded that the charged current on the zinc oxide thin film can be controlled with changing concentration of precursor solution in CFR method. The charged currents on the zinc oxide thin films also decreased when ZnO thin film is exposed under hydrogen sulfide of 500 ppmv at $300^{\circ}C$ for 5 min. From these results, it could be confirmed that the zinc oxide thin film prepared by CFR method can be used for the detection of sulfur compounds.

키워드

참고문헌

  1. Liang, Y., Zhang, X. T., Liu, Z., Zhang, Q. E., Zhao, C. Z., Gao, H. and Zhang, Z. G., "Local Homoepitzsy and Optical Properties of Well-ordered ZnO Nanowires," Physica E, 33, 191(2006). https://doi.org/10.1016/j.physe.2006.02.005
  2. Cheng, H., Cheng, J., Zhang, Y. and Wang, Q.-M., "Large-scale Fabrication of ZnO Micro- and Nano-Structures by Microwave Thermal Evaporation Deposition", J. Cryst. Growth., 299, 34(2007). https://doi.org/10.1016/j.jcrysgro.2006.10.245
  3. Hu, J. Q., Li, Q., Meng, X. M., Lee, C. S. and Lee, S. T., "Thermal Reduction Route to the Fabrication of Coaxial Zn/ZnO Nanocables and ZnO Nanotube, " Chem. Mater., 15, 305(2003). https://doi.org/10.1021/cm020649y
  4. Wu, J.-J., Liu, S.-C., Wu, C.-T., Chen, K.-H. and Chen, L.-C., "Hetero-Structures of ZnO-Zn Coaxial Nanocables and ZnO Nanotube, " Appl. Phys. Lett., 81, 1312(2002). https://doi.org/10.1063/1.1499512
  5. Wang, X. J., Buyanova, I. A., Chen, W. M., Pan, C. J. and Tu, C. W., "Optical Characterization Studies of Grown-in Defects in ZnO Epilayers Grown by Molecular-beam Epitaxy," Physica B, Condensed Matter, In press(2007).
  6. Yi, S.-H., Choi, S.-K., Jang, J.-M., Kim, J.-A. and Jung, W.-G., "Low-temperature Growth of ZnO Nanorods by Chemical Bath Deposition," J. Colloid Interface. Sci., 313, 705 (2007). https://doi.org/10.1016/j.jcis.2007.05.006
  7. Cheng, H.-C., Chen, C.-F. and Lee, C.-C., "Thin-film Transistors with Active Layers of Zinc Oxide(ZnO) Fabricated by Lowtemperature Chemical Bath Method," Thin Solid Films, 498, 142 (2006). https://doi.org/10.1016/j.tsf.2005.07.101
  8. Park, W. I., Kim, D. H., Jung, S.-W. and Yi, G.-C., "Metalorganic Vapor-phase Epitaxial Growth of Vertically Well-aligned ZnO Nanorods," Appl. Phys. Lett., 80, 4232(2002). https://doi.org/10.1063/1.1482800
  9. Jeong, M.-C., Oh, B.-Y., Lee, W. and Myoung, J.-M., "Comparative Study on the Growth Characteristics of ZnO Nanowires and Thin Films by Metalorganic Chemical Vapor Deposition (MOCVD)," J. Crys. Growth., 268, 149(2004). https://doi.org/10.1016/j.jcrysgro.2004.05.019
  10. Lee, W., Jeong, M.-C. and Myoung, J.-M., "Catalyst-free Growth of ZnO Nanowires by Metal-organic Chemical Vapor Deposition (MOCVD) and Thermal Evaporation", Acta Mater., 52, 3949(2004). https://doi.org/10.1016/j.actamat.2004.05.010