Transactions on Electrical and Electronic Materials

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
권호 표지
DOI QR코드

DOI QR Code

Etching Characteristics of Au Thin Films using Inductively Coupled CF4 / Cl2 / Ar Plasma

  • Kim Dong-Pyo (Department of Electrical and Electronics Engineering, Chung-Ang University) ;
  • Kim Chang-Il (Department of Electrical and Electronics Engineering, Chung-Ang University)
  • Published : 2003.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

The etching of Au thin films has been performed in an inductively coupled $CF_4 / Cl_2 / Ar$ plasma. The etch properties including etch rate and selectivity were examined as $CF_4$ content adds from o to $30\%$ to $Cl_2/Ar$ plasma. The $Cl_2/(Cl_2 + Ar)$ gas mixing ratio was fixed at $20\%$. Other parameters were fixed at an rf power of 700 W, a dc bias voltage of -150 V, a chamber pressure of 15 mTorr, and a substrate temperature of $30^{\circ}C$. The highest etch rate of the Au thin film was 370 nm/min at a $10\%$ additive $CF_4$ into $Cl_2/Ar$ gas mixture. The surface reaction of the etched Au thin films was investigated using x-ray photoelectron spectroscopy (XPS) analysis. The XPS analysis shows that the intensities of Ail peaks are changed, indicating that there is a chemical reaction between Cl and Au. Au-Cl is hard to remove on the surface because of its high melting point. However, etching products can be sputtered by Ar ion bombardment.

Keywords

References

  1. H. Ohtake, S. Samukawa, H. Oikawa, and Y. Nashimoto, 'Enhancement of reactivity in Au etching by pulse time modulated Cb plasma', Jpn. J. Appl. Phys., Vol. 37, No. 4B, p. 2311,1998 https://doi.org/10.1143/JJAP.37.2311
  2. R. M. Ranade, S. S. Ang, and W. D. Brown, 'Reactive ion etching of thin gold films', J. Electrochem. Soc., Vol. 140, No. 12, p. 3676, 1993 https://doi.org/10.1149/1.2221148
  3. F. T. Aldridge, 'Highspeed anisotropic reactive ion etching of gold films', J. Electrochem. Soc., Vol. 142, No.5, p. 1563, 1995 https://doi.org/10.1149/1.2048613
  4. Y. S. Chang, D. P. Kim, C. I. Kim, E. G. Chang, and S. J. Lee, 'Etching characteristics of gold thin films using inductively coupled Cb/Ar Plasma', J. of KIEEME(in Korean), Vol. 15, No. 12, p. 1011,2002
  5. D, P. Kim, C. I. Kim, W. J. Lee, B. G. Yu, T. H. Kim, and E. G. Chang, 'Etching characteristics of SrBhTaz09 thin film with adding Cl2, into CF4/Ar plasma', J. of KIEEME(in Korean), Vol. 14, No.9, p. 714, 2001
  6. T. Kanashima and M. Okuyama, 'Analyses of high frequency capacitance voltage characteristics of Metal Ferroelectrics Insulator Silicon structure', Jpn. J. Appl. Phys., Vol. 38, No. 4A, p. 2044, 1999 https://doi.org/10.1143/JJAP.38.2044
  7. J. K. Jung and W. J. Lee, 'Dry etching characteristics of Pb(Zr,Ti)03 films in CF4 and C12/CF4 inductively coupled plasmas', Jpn, J. Appl. Phys., Vol. 40, No. 3A, p. 1408,2001 https://doi.org/10.1143/JJAP.40.1408
  8. N. C. M. Fuller, V. M. Donnelly, and I. P. Herman, 'Electron temperatures of inductively coupled Cl2 Ar plasmas', J. Vac. Sci. Technol' A, Vol. 20, Issue 1, p. 170,2002 https://doi.org/10.1116/1.1427884
  9. N. C. M. Fuller, V. M. Donnelly, and I. P. Herman,'Optical actinometry of C12, Cl, Cl+. and Ar+ densities in inductively coupled C12-Ar plasmas', J. Appl. Phys., Vol. 90, Issue 7, p. 3182,2001 https://doi.org/10.1063/1.1391222
  10. S. W. Shin, C. I. Kim, and E. G. Chang, 'The study of etching Characteristic in SrBi2Ta2O9 thin film by optical emission spectroscopy', J. of KIEEME(in Korean), Vol. 14, No.3, p. 185,2001