Etch Characteristics of Zinc Oxide Thin Films in a Cl2/Ar Plasma

Cl2/Ar 플라즈마를 이용한 ZnO 박막의 식각 특성

  • Min, Su Ryun (Department of Chemical Engineering, Inha University) ;
  • Lee, Jang Woo (Department of Chemical Engineering, Inha University) ;
  • Cho, Han Na (Department of Chemical Engineering, Inha University) ;
  • Chung, Chee Won (Department of Chemical Engineering, Inha University)
  • 민수련 (인하대학교 화학공학과) ;
  • 이장우 (인하대학교 화학공학과) ;
  • 조한나 (인하대학교 화학공학과) ;
  • 정지원 (인하대학교 화학공학과)
  • Received : 2006.07.14
  • Accepted : 2006.11.14
  • Published : 2007.02.10

Abstract

The etching of zinc oxide (ZnO) thin films has been studied using a high density plasma in a $Cl_2/Ar$ gas. The etch characteristics of ZnO thin films were systematically investigated on varying $Cl_2$ concentration, coil rf power, dc-bias voltage, and gas pressure. With increasing $Cl_2$ concentration, the etch rate of ZnO thin film increased, the redeposition around the etched patterns decreased but the sidewall slope of the etched patterns slanted. As the coil rf power and dc-bias voltage increased, the etch rates of ZnO thin films increased and etch profiles of ZnO thin films were improved. With increasing gas pressure, the etch rate of ZnO thin films slightly increased but little change in etch profile was observed. Based on these results, the optimal etching conditions of ZnO thin film were selected. Finally, the etching of ZnO thin films with a high degree of anisotropy of approximately $75^{\circ}{\sim}80^{\circ}$ without the redepositions and residues was successfully achieved at the etching conditions of 20% $Cl_2$ concentration, coil rf power of 1000 W, dc-bias voltage of 400 V, and gas pressure of 5 mTorr.

Acknowledgement

Supported by : 인하대학교

References

  1. J. M. Lee, K. K. Kim, S. J. Park, and W. K. Choi, Appl. Phys. Lett., 78, 3842 (2001) https://doi.org/10.1063/1.1379061
  2. J. S. Park, H. J. Park, T. B. Hahn, and G. C. Yi, J. Vac. Sci. Technol. B, 21, 800 (2003) https://doi.org/10.1116/1.1563252
  3. J. M. Lee, K. M. Chang, K. K. Kim, W. K. Choi, and S. J. Park, J. Electrochem. Soc., 148, G1 (2001) https://doi.org/10.1149/1.1344554
  4. K. Ip, K. H. Baik, M. E. Overberg, E. S. Lanbers, Y. W. Heo, D. P. Norton, F. Ren, and J. M. Zavada, Appl. Phys. Lett., 81, 3546 (2002) https://doi.org/10.1063/1.1519095
  5. K. Ip, M. E. Overberg, K. W. Biak, R. G. Wilson, S. O. Kucheyev, J. S. Williams, C. Jagadish, F. Ren, Y. W. Heo, D. P. Norton, J. M. Zavada, and S. J. Pearton, Solid-state Electronics, 47, 2289 (2003)
  6. R. Groenen, M. Creatore, and M. C. M. van de Sanden, Applied Surface Science, 241, 321 (2005) https://doi.org/10.1016/j.apsusc.2004.07.034
  7. S. W. Na, M. H. Shin, Y. M. Chung, J. G. Han, S. H. Jeung, J. H. Boo, and N. E. Lee, Microelectron. Eng., 83, 328 (2006) https://doi.org/10.1016/j.mee.2005.09.007
  8. I. Volintiru, M. Creatore, J. L. Linden, and M. C. M. van de Sanden, Superlattices and Microstructures, 39, 348 (2006) https://doi.org/10.1016/j.spmi.2005.08.061
  9. J. Müller, G. Schope, O. Rech, M. Ruske, J. Trube, B. Szyszka, X. Jiang, and G. Brauer, Thin Solid Films, 392, 327 (2001) https://doi.org/10.1016/S0040-6090(01)01052-5
  10. K. Takahashi, H. Funakubo, N. Ohashi, and H. Haneda, Thin Solid Films, 486, 42 (2005) https://doi.org/10.1016/j.tsf.2004.11.221
  11. H. K. Kim, J. W. Bae, K. K. Kim, S. J. Park, T. Y. Seong, and I. Adesida, Thin Solid Films, 447, 90 (2004) https://doi.org/10.1016/j.tsf.2003.09.028
  12. I. H. Park, J. W. Lee, and C. W. Chung, J. Korean Ind. Eng. Chem., 16, 853 (2005)
  13. D. R. Lide, CRC Handbook of Chemistry and Physics 81st Edition, 4-99, CRC Press, New York (2000)