Issue
Korean Journal of Chemical Engineering,
Vol.39, No.11, 3121-3128, 2022
Dissolution of copper and copper oxide in aqueous solution containing
Using a component having an amine group (-NH2) or a carboxyl group (-COOH) for a cleaning solution, the etching rates of copper oxide and copper were analyzed by measuring the solubility of copper to evaluate the etch residue removal properties. Based on this, it was attempted to establish the basis of a cleaning process for removing etch residues in the copper back end of line (BEOL) process. In addition, the etch rate and surface structure change of fluorine-doped fluorosilicate glass (FSG), Black Diamond (BD), and methyl group-doped organosilicate glass (OSG), which are low-k dielectric materials, were analyzed. The copper oxide etching rate of the component having an amine group showed a tendency to increase as the basicity of the solution increased. Also, the solubility of copper oxide in the amine solution decreased with the increase of the carbon length in the amine molecular structure. The solution having a carboxyl group compared to the amine group has a high etching rate for the low-k dielectric material. The amine component showed reactivity only in the basic region and, on the contrary, the carboxyl group component is reactive only in the acidic region.
[References]
  1. Martinez MA, Soild State Technol., 37, 26, 1994
  2. Shamiryan D, Abell T, Lacopi F, Maex K, Mater. Today, 7, 34, 2004
  3. Zheng YS, Guo Q, Su YJ, Foo PD, Microelectron. J., 34, 109, 2003
  4. Lu D, Kumar R, Chang CK, Du AY, Wong TKS, Microelectron. Eng., 77, 63, 2005
  5. Wang Y, Graham SW, Chan L, Loong S, J. Electrochem. Soc., 144, 1522, 1997
  6. Maruyama T, Fujiwara N, Siozawa K, Yoneda M, Jpn. J. Appl. Phys., 35, 2463, 1996
  7. Baggerman JAG, Visser RJ, Collaert EJH, J. Appl. Phys., 75, 758, 1994
  8. Ohmi T, J. Electrochem. Soc., 143, 2957, 1996
  9. Loewenstein LM, Mertens PW, J. Electrochem. Soc., 146, 3886, 1999
  10. Cady WA, Varadarajan M, J. Electrochem. Soc., 143, 2064, 1996
  11. Reinhardt KA, Kern W, Handbook of silicon wafer cleaning technology, 3rd ed., Elsevier (2018).
  12. Venkataraman N, Raghavan S, Microelectron. Eng., 87, 1689, 2010
  13. Ko CK, Lee WG, Korean Chem. Eng. Res., 54, 548, 2016
  14. Ko CK, Lee WG, Korean Chem. Eng. Res., 59, 632, 2021
  15. Sircar SC, Wiled DR, J. Electrochem. Soc., 107, 164, 1960
  16. Aksu S, Doyle FM, J. Electrochem. Soc., 149, B340, 2002
  17. Sircar SC, Wiled DR, J. Electrochem. Soc., 107, 367, 1960
  18. Carter MK, Small E, Cernat M, Hansen B, J. Electrochem. Soc., 150, B52, 2003
  19. Wu YF, Tsai TH, Microelectron. Eng., 84, 2790, 2007
  20. Gorantla VRK, Babel A, Pandija S, Babu SV, Electrochem. Solid State Lett., 8, G131, 2005
  21. Gorantla V, Goia D, Matijević E, Babu SV, J. Electrochem. Soc., 152, G912, 2005
  22. Aksu S, Doyle FM, J. Electrochem. Soc., 149, B340, 2002
  23. Ko CK, Lee WG, Surf. Interface Anal., 44, 94, 2012
  24. Ko CK, Lee WG, Surf. Interface Anal., 42, 1128, 2010
  25. Ding ZJ, Wang YP, Liu WJ, Ding SJ, Baklanov MR, Zhang DW, J. Phys. D-Appl. Phys., 51, 115103, 2018