Transactions on Electrical and Electronic Materials

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Stability of H2O2 as an Oxidizer for Cu CMP

  • Lee, Do-Won (School of Electrical and Electronics Engineering, Chung-Ang University) ;
  • Kim, Tae-Gun (School of Electrical and Electronics Engineering, Chung-Ang University) ;
  • Kim, Nam-Hoon (School of Electrical and Electronics Engineering, Chung-Ang University) ;
  • Kim, Sang-Yong (School of Electrical and Electronics Engineering, Chung-Ang University) ;
  • Chang, Eui-Goo (School of Electrical and Electronics Engineering, Chung-Ang University)
  • Published : 2005.02.01
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Abstract

Chemical mechanical polishing is an essential process in the production of copper-based chips. On this work, the stability of hydrogen peroxide ($H_{2}O_{2}$) as an oxidizer of copper CMP slurry has been investigated. $H_{2}O_{2}$ is known as the most common oxidizer in copper CMP slurry. But $H_{2}O_{2}$ is so unstable that its stabilization is needed using as an oxidizer. As adding KOH as a pH buffering agent, stability of $H_{2}O_{2}$ decreased. However, $H_{2}O_{2}$ stability in slurry went up with putting in small amount of BTA as a film forming agent. There was no difference of $H_{2}O_{2}$ stability between pH buffering agents KOH and TMAH at similar pH value. Addition of $H_{2}O_{2}$ in slurry in advance of bead milling led to better stability than adding after bead milling. Adding phosphoric acid resulted in the higher stability. Using alumina C as an abrasive was good at stabilizing for $H_{2}O_{2}$.

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References

  1. R. Carpio, J. Farkas, and R. Jairath, 'Initial study on copper CMP slurry chemistries', Thin Solid Films, Vol. 266, No.2, p. 238, 1995
  2. S.-Y. Kim, Y.-J. Seo, T.-H. Kim, W.-S. Lee, C.-I. Kim, and E.-G. Chang, 'A study for global planarization of multilevel metal by CMP', J. of KIEEME(in Korean), Vol. 11, No. 12, p. 1084, 1998
  3. N.-H. Kim, S.-Y. Kim, Y.-J. Seo, T.-H. Kim, and E.G. Chang, 'A study on semi abrasive free slurry including acid colloidal silica for copper chemical mechanical planari-zation', J. of KIEEME(in Korean), Vol. 17, No.3, p. 272, 2004
  4. Z. Stavreva, D. Zeidler, M. Plotner, and K. Drescher, 'Chemical mechanical polishing of copper for multilevel metallization', Surf. Sci., Vol. 91, No. 1-4, p. 192, 1995 https://doi.org/10.1016/0169-4332(95)00086-0
  5. Q. Luo, S. Ramarajan, and S. V. Babu, 'Modification of the preston equation for the chemical-mechanical polishing of copper', Thin Solid Films, Vol. 335, No. 1-2, p. 166, 1998 https://doi.org/10.1016/S0040-6090(98)00861-X
  6. B. J. Palla and D. O. Shah, J. 'Stabilization of high ionic strength slurries using surfactant mixtures: molecular factors that determine optimal stability', Colloid and Interface Sci., Vol. 256, No.1, p. 143, 2002
  7. Q. Luo, D. R. Campbell, and S. V. Babu, 'Stabilization of alumina slurry for chemical-mechanical polishing of copper', Langmuir, Vol. 12, No. 15, p. 3563, 1996