Journal of Materials Science

, Volume 42, Issue 12, pp 4591–4602 | Cite as

Physical properties of low-k films based on the co-condensation of methyltrimethoxysilane with a bridged silsesquioxane

  • B. R. KimEmail author
  • J. W. Kang
  • K. Y. Lee
  • J. M. Son
  • M. J. Ko


Though spin-on organosilicates are considered as the promising candidates of low dielectric constant materials, it is necessary for a successful integration to improve mechanical strength such as modulus and fracture toughness. In this study, five sets of MTMS–BTMSE copolymers were synthesized and characterized while the monomer content of BTMSE (bis(trimethoxysilyl)ethane) was varied from 9.1 to 47.3 mol% vs. MTMS (methyltrimethoxysilane). In parallel with the measurement of dielectric constant, four different tests were carried out to evaluate mechanical properties of the MTMS–BTMSE copolymers. Modulus was measured by the nanoindentation technique and the modified edge lift-off test (MELT) was employed to extract adhesive fracture toughness quantitatively. In addition, residual stress was calculated by sensing the change in radius of curvature of the substrate. The chemical structure of the copolymers was also analyzed with FTIR and NMR. Network formation was enhanced as the amount of BTMSE increased, which led to improvement of modulus and the increase in refractive index and dielectric constant. However, an increasing rate of fracture toughness by the MELT was not proportional to the increase in the amount of BTMSE, which implied that it was necessary to optimize the composition of the copolymers since adhesion strength was conjectured the most critical factor for a successful integration.


Residual Stress Dielectric Constant Fracture Toughness Magic Angle Spin Copolymer Film 


  1. 1.
    International Technology Roadmap for Semiconductors (2003) Semiconductor Industry Association, San Jose, CAGoogle Scholar
  2. 2.
    Padovani AM, Rhodes L, Allen SAB, Kohl PA (2002) J Electrochem Soc 149:F149CrossRefGoogle Scholar
  3. 3.
    Padovani AM, Riester L, Rhodes L, Allen SAB, Kohl PA (2002) J Electrochem Soc 149:F171CrossRefGoogle Scholar
  4. 4.
    Toivola Y, Kim S, Cook RF, Char K, Lee J-K, Yoon DY, Rhee H-W, Kim SY, Jin MY (2004) J Electrochem Soc 151:F45CrossRefGoogle Scholar
  5. 5.
    Cook RF, Liniger EG (1999) J Electrochem Soc 146:4439CrossRefGoogle Scholar
  6. 6.
    Toivola Y, Thurn J, Cook RF (2002) J Electrochem Soc 149:F9CrossRefGoogle Scholar
  7. 7.
    Kim S, Toivola Y, Cook RF, Char K, Chu S-H, Lee J-K, Yoon DY, Rhee H-W (2004) J Electrochem Soc 151:F37CrossRefGoogle Scholar
  8. 8.
    Oliver WC, Pharr GM (1992) J Mater Res 7:1564CrossRefGoogle Scholar
  9. 9.
    Zhao J-H, Malik I, Ryan T, Ogawa ET, Ho PS, Shih W-Y, McKerrow AJ, Taylor KJ (1999) Appl Phys Lett 74:944CrossRefGoogle Scholar
  10. 10.
    Shaffer EO, Mills ME, Hawn DD, Van Gestel M, Knorr A, Gundlach H, Kumar K, Kaloyeros AE, Geer RE (1998) Mater Res Soc Symp Proc 511:133CrossRefGoogle Scholar
  11. 11.
    Ho PS, Leu J, Morgan M, Kiene M, Zhao J-H, Hu C (2003) In: Murarka SP, Eizenberg M, Shina AK (eds) Interlayer dielectrics for semiconductor technologies. Elsevier Academic Press, London, p 37Google Scholar
  12. 12.
    Flannery CM, Murray C, Streiter I, Shultz SE (2001) Thin Solid Films 388:1CrossRefGoogle Scholar
  13. 13.
    Ma Q (1997) J Mater Res 12:840CrossRefGoogle Scholar
  14. 14.
    Vella JB, Adhihetty IS, Junker K, Volinsky AA (2003) Int J fracture 119/120:487CrossRefGoogle Scholar
  15. 15.
    Nagai H, Maekawa K, Iwashita M, Muramatsu M, Kubota K, Hinata K, Kokubo T (2004) In: Proceedings IITC, p 145Google Scholar
  16. 16.
    Oh W, Shin TJ, Ree M, Jin MY, Char K (2002) Macromol Chem Phys 203:801CrossRefGoogle Scholar
  17. 17.
    Lee H-J, Lin EK, Wang H, Wu W-L, Chen W, Moyer ES (2002) Chem Mater 14:1845CrossRefGoogle Scholar
  18. 18.
    Nay RJ, Warren OL, Yang D, Wyrobek TJ (2004) Microelectron Eng 75:103CrossRefGoogle Scholar
  19. 19.
    Hay JC, Liniger EG, Liu X-H (2000) In: Mittal KL (ed) Adhesion measurements of films and coatings, 2nd edn. VSP, Utrecht, p 205Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • B. R. Kim
    • 1
    Email author
  • J. W. Kang
    • 1
  • K. Y. Lee
    • 1
  • J. M. Son
    • 1
  • M. J. Ko
    • 1
  1. 1.LG Chem. Ltd., Research ParkDaejeonKorea

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