Journal of the Korean Society for Heat Treatment (열처리공학회지)

The Korean Society for Heat Treatment (한국열처리공학회)
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Effect of Annealing Temperatures on the Properties of Zn2SnO4 Thin Film

열처리 온도에 따른 Zn2SnO4 박막의 특성

  • Shin, Johngeon (Division of Materials Science and Engineering, Silla University) ;
  • Cho, Shinho (Division of Materials Science and Engineering, Silla University)
  • 신종언 (신라대학교 공과대학 신소재공학부) ;
  • 조신호 (신라대학교 공과대학 신소재공학부)
  • Received : 2019.02.18
  • Accepted : 2019.03.15
  • Published : 2019.03.31
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Abstract

$Zn_2SnO_4$ thin films were deposited on quartzs substrates by using radio-frequency magnetron sputtering system. Thermal treatments at various temperatures were performed to evaluate the effect of annealing temperatures on the properties of $Zn_2SnO_4$ thin films. Surface morphologies were examined by using field emission-scanning electron microscopy and showed that sizes of grains were slightly increased and grain boundaries were clear with increasing annealing temperatures. The deposited $Zn_2SnO_4$ thin films on quartzs substrates were amorphous structures and no distinguishable crystallographic changes were observed with variations of annealing temperatures. The optical transmittance was improved with increasing annealing temperatures and was over 90% in the wavelength region between 350 and 1100 nm at the annealing temperature of $600^{\circ}C$. The optical energy bandgaps, which derived from the absorbance of $Zn_2SnO_4$ thin films, were increased from 3.34 eV to 3.43 eV at the annealing temperatures of $450^{\circ}C$ and $600^{\circ}C$, respectively. As the annealing temperature was increased, the electron concentrations were decreased. The electron mobility was decreased and resistivity was increased with increasing annealing temperatures with exception of $450^{\circ}C$. These results indicate that heat treatments at higher annealing temperatures improve the optical and electrical properties of rf-sputtered $Zn_2SnO_4$ thin films.

Keywords

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Fig. 1. SEM images of the surfaces of the Zn2SnO4 thin films annealed at (a) 450°C, (b) 500°C, (c) 550°C, and (d) 600°C.

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Fig. 2. X-ray diffraction patterns of the Zn2SnO4 thin films annealed at (a) 450°C, (b) 500°C, (c) 550°C, and (d) 600°C.

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Fig. 3. Transmittances of the Zn2SnO4 thin films annealed at several temperatures. The inset shows absorbance spectra as a function of wavelength.

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Fig. 4. Optical energy bandgaps for the Zn2SnO4 thin films annealed at (a) 450°C, (b) 500°C, (c) 550°C, and (d) 600°C.

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Fig. 5. Electron concentration, mobility, and resistivity for the Zn2SnO4 thin films annealed at (a) 450°C, (b) 500°C, (c) 550°C, and (d) 600°C.

References

  1. H. Ohta, M. Orita, M. Hirano, H. Tanji, H. Kawazoe, and H. Hosono : Appl. Phys. Lett. 76 (2000) 2740. https://doi.org/10.1063/1.126461
  2. S. Takada : J. Appl. Phys., 73 (1993) 4739. https://doi.org/10.1063/1.354091
  3. T. Makino, C. H. Chia, N. T. Tuan, Y. Segawa, M. Kawasaki, A. Ohtomo, K. Tamura, and H. Koinuma : Appl. Phys. Lett. 76 (2000) 3549. https://doi.org/10.1063/1.126703
  4. P. Lippens, A. Segers, J. Haemers, and R. De Gryse : Thin Solid Films, 317 (1998) 405. https://doi.org/10.1016/S0040-6090(97)00632-9
  5. C. Guillen and J. Herrero : Vacuum 84 (2010) 924. https://doi.org/10.1016/j.vacuum.2009.12.015
  6. Y. J. Jo, J. Kim, S. Han, J. Kwak, and J. Lee : J. Kor. Inst. Met. & Mater. 47 (2009) 44.
  7. K. Goto, T. Kawashima, and N. Tanabe : Solar Energy Mater. & Solar cells, 90 (2006) 3215.
  8. Z. Fu, B. Lin, and J. Zu : Thin Solid Films 402 (2002) 302. https://doi.org/10.1016/S0040-6090(01)01363-3
  9. D. C. Look, D. C. Reynolds, C. W. Litton, R. L. Jones, D. B. Eason, and G. Cantwell : Appl. Phys. Lett. 81 (2002) 1830. https://doi.org/10.1063/1.1504875
  10. J. Ma, D. Zhang, J. Zhao, C. Tan, T. Yang, and H. Ma : Appl. Surface Sci. 151 (1999) 239. https://doi.org/10.1016/S0169-4332(99)00279-2
  11. P. Nunes, D. Costa, E. Fortunato, and R. Martins : Vacuum 64 (2002) 293. https://doi.org/10.1016/S0042-207X(01)00323-2
  12. S. Cho : Trans. Electr. Electron. Mater. 10 (2009) 185. https://doi.org/10.4313/TEEM.2009.10.6.185
  13. F. Yakuphanoglu, M. Sekerci, and O. F. Ozturk : Opt. Comm. 239 (2004) 275. https://doi.org/10.1016/j.optcom.2004.05.038
  14. S. Cho : J. Kor. Vacuum Soc. 18 (2009) 377. https://doi.org/10.5757/JKVS.2009.18.5.377