Skip to main content
SpringerLink
Log in

Physical Vapor Deposition Barriers for Cu metallization - PVD Barriers

  • Chapter
  • First Online:
Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications

  • 1905 Accesses

Abstract

Cu is an interstitial impurity in Si and its diffusivity in Si is faster than other transition metals and of the order of 10−5 to 10−7 cm2/s in the temperature range of 200–500°C [1]. Electronically, Cu is a deep-level dopant in Si and forms various donor and acceptor levels, inducing current leakage [2, 3]. In a multilayered device structure, Cu diffuses through a dielectric layer and reaches a Si substrate under electric bias field [4]. In order to prevent Cu diffusion, a barrier layer is necessary at an interface between Cu and the dielectric layers. By the use of high-resistivity barrier metal, the effective resistivity of interconnect lines increases with the advancement of the technology node as shown in Fig. 21.1 [5, 6]. For a fixed barrier thickness of 10 nm, for example, effective resistivity increases rapidly from 2.35 μΩ cm for the 65 nm node to 2.85 μΩ cm for the 32 nm node. Meanwhile, the effective resistivity of 2.2 μΩ cm should be maintained in order to minimize RC delay [7]. This recommendation by the International Technology Roadmap for Semiconductors (ITRS) determines a required barrier thickness at a given technology node. In the 32 nm node, the barrier thickness should be 3.5 nm, approximately 10 atomic layers to prevent interdiffusion between Cu and the dielectric layer. In order to achieve this requirement, a proper barrier material should be deposited using proper deposition techniques and conditions. Wang et al. summarized the published data as of the year 1993 together with their investigation of TiW barrier [8]. Kaloyeros and Eisenbraun [9] published an excellent review of barrier materials as of 2000. In their review article, advantages and limitations of various barrier materials were described in detail based on numerous experimental works by others. Readers can find in this article how and why Ta/TaN barrier had come to use for the Cu interconnect. Since then, technology has rapidly advanced along the line of the ITRS roadmap. Once the technology node entered to a sub-micrometer range, barrier thickness becomes a critical issue to ensure expected performance and reliability of advanced devices. Barrier materials and processes need to be revisited from fundamental viewpoint. In this chapter, the issues of physical vapor deposited (PVD) barrier will be discussed in terms of metallurgical and thermodynamic aspects.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 129.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 169.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 169.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

References

  1. Graff, K.: Metal Impurities in Silicon-Device Fabrication, Springer-Verlag, Berlin, 29 (1999)

    Google Scholar 

  2. Collins, C. B. and Carlson, R. O.: Properties of silicon doped with iron or copper. Phys. Rev. 108, 1405 (1957)

    Article  Google Scholar 

  3. Toyama, N.: Copper impurity levels in silicon. Solid State Electron. 26(1), 37 (1983)

    Article  CAS  Google Scholar 

  4. Shacham-Diamond, Y.; Dedhia, A.; Hoffstetter, D.; and Oldham, W. G.: Copper transport in thermal SiO2. J. Electrochem. Soc. 140(8), 2427 (1993)

    Article  Google Scholar 

  5. Kapur, P.; McVittie, J. P.; and Saraswat, K. C.: Technology and reliability constrained future copper interconnects-part I: Resistance modeling. IEEE Trans. Electron Devices 49(4), 590 (2002)

    Article  CAS  Google Scholar 

  6. Shibata, H.: Practical roadmap and approach of multi-level interconnect technology for realizing over GHz system-on-chip. Proceedings of International Symposium on ULSI Process Integration of the 199th Electro-Chemical Society Meeting. 430 (2001)

    Google Scholar 

  7. International Technology Roadmap for Semiconductors (2003)

    Google Scholar 

  8. Wang, S-Q.; Suthat, S.; Hoeflich, K.; and Burrow, B. J.: Diffusion barrier properties of TiW between Si and Cu. J. Appl. Phys. 73(5), 2301 (1993)

    Article  CAS  Google Scholar 

  9. Kaloyeros, A. E. and Eisenbraun, E.: Ultrathin diffusion barriers/liners for gigascale copper metallization. Annu. Rev. Mater. Sci. 30, 363 (2000)

    Article  CAS  Google Scholar 

  10. Iwamori, S.; Miyashita, T.; Fukuda, S.; Fukuda, N.; and Sudoh, K.: Effect of a metallic interfacial layer on peel strength deterioration between a Cu thin film and a polyimide substrate. J. Vac. Sci. Technol. B 15(1), 53 (1997)

    Article  CAS  Google Scholar 

  11. Gjostein, N. A.: Diffusion in Metals. Westerville, OH, ASM (1973)

    Google Scholar 

  12. Holloway, K.; Fryer, P. M.; Cabral. C.; Harper, J. M.; Bailey, P. J.; and Kelleher, K. H.: Tantalum as a diffusion barrier between copper and silicon: Failure mechanism and effect of nitrogen additions. J. Appl. Phys. 71(11), 5433 (1992)

    Article  CAS  Google Scholar 

  13. Choe, H. S. and Danek, M.: MOCVD TiN diffusion barriers for copper interconnects. Proc. IEEE Int. Interconnect Technology Conference 62 (1999)

    Google Scholar 

  14. Olowolafe, J.; Mogab, C.; Gregory, R.; and Kottke, M.: Interdiffusions in Cu/reactive-ion-sputtered TiN, Cu/chemical-vapor-deposited TiN, Cu/TaN, and TaN/Cu/TaN thin-film structures: Low temperature diffusion analyses. J. Appl. Phys. 72(9), 4099 (1992)

    Article  CAS  Google Scholar 

  15. Ko, D.; Park, B.; Kim, Y.; Ha, J.; and Park, Y.: Advanced Metallization and Interconnect Systems for ULSI Applications in 1995, Mater. Res. Soc., Pittsburgh, 257 (1996)

    Google Scholar 

  16. Bai, G.; Wittenbrock, S.; Ochoa, V.; and Bohr, M.: Effectiveness and reliability of metal diffusion barriers for copper interconnects. Mater. Res. Soc. Symp. Proc. 403, 501 (1996)

    CAS  Google Scholar 

  17. Kim, K.: Advanced Metallization and Interconnect Systems for ULSI Applications. Mater. Res. Soc., Pittsburgh, 281 (1995)

    Google Scholar 

  18. Min, K.-H.; Chun, K.-C.; and Kim, K.-B.: Comparative study of tantalum and tantalum nitrides (Ta2N and TaN) as a diffusion barrier for Cu metallization. J. Vac. Sci. Technol. B 14(5), 3263 (1996)

    Article  CAS  Google Scholar 

  19. Eustathopoulos, N.; Nicholas, M. G.; and Drevet, B.: Wettability at High Temperatures, Pergamon, Amsterdam (1999)

    Google Scholar 

  20. Naidich, Yu. V.: Wettability of solids by molten metals. In Progress in Surface and Membrane Science. Cadenhead, D. A. and Danielli, J. F., Eds. Academic Press, New York, 14, 353 (1981)

    Google Scholar 

  21. Chatain, D.; Rivollet, I.; and Eustathopoulos, N.: Thermodynamic adhesion in nonreactive liquid metal-alumina systems. J. Chem. Phys. 83, 561 (1986)

    CAS  Google Scholar 

  22. Naidich, Yu. V.: Contact phenomena in molten metals. Naukova Dumka; Kiev (1972)

    Google Scholar 

  23. Naidich, Yu. V.: Wettability of halides with molten metals, Physico-chemical and practical aspects. Powder Metallurgy and Metal Ceramics 39, 355 (2000)

    Article  CAS  Google Scholar 

  24. Naidich, Yu. V. and Taranets, N. Y.: Wettability of aluminum nitride by tin aluminum melts. J. Mater. Sci. 33, 3993 (1998)

    Article  CAS  Google Scholar 

  25. Ljunberg, L. and Warren, R.: Wetting of silicon nitride with. selected metals and alloys. Ceram. Eng. Sci. Proc. 10, 1655 (1989)

    Article  Google Scholar 

  26. Nicholas, M. G.; Mortimer, D. A.; Jones, L. M.; and Crispin, R. M.: Some observations on the wetting and bonding of nitride ceramic. J. Mater. Sci. 25, 2679 (1990)

    Article  CAS  Google Scholar 

  27. Ramqvist, L.: Wetting of Metallic Carbides by Liquid Copper, Nickel, Cobalt and Iron. Int. J. Powder Metall. 1(4), 2 (1965)

    CAS  Google Scholar 

  28. Sinke, W.; Frijlink, P.; and Saris, F.: Oxygen in titanium nitride diffusion barriers. Appl. Phys. Lett. 47(5), 471 (1985)

    Article  CAS  Google Scholar 

  29. Park, K. and Kim, K.: Comparative Study on the Titanium Nitride (TiN) As a diffusion Barrier Between Al/Si and Cu/Si: Failure Mechanism and Effect of `Stuffing. Mater. Res. Soc. Symp. Proc. 391, 211 (1995)

    CAS  Google Scholar 

  30. Doussin, L. and Omnes, J.: Technical report (report 1/1259 M), Office National d’Etudes et de Recherches Aerospariales, Direction des Materiaux, Chatillon, France (1967)

    Google Scholar 

  31. Nicholas, M. and Poole, D. M.: The influence of oxygen on wetting and bonding in Cu-W sys-. Tem. J. Mater. Sci. 2(3), 269 (1967)

    Article  CAS  Google Scholar 

  32. Lane, M. W.; Liniger, E. G.; and Lloyd, J. R.: Relationship between interfacial adhesion and electromigration in Cu metallization. J. Appl. Phys. 93(3), 1417 (2003)

    Article  CAS  Google Scholar 

  33. Rossnagel, S. M.: Sputter deposition for semiconductor: Manufacturing. IBM J. Res. Develp. 43, 163 (1999)

    Article  CAS  Google Scholar 

  34. Cuomo, J. J. and Rossnagel, S. M.: Hollow Cathode Enhanced Magnetron Sputtering. J. Vac. Sci. Technol. A 4, 393 (1986)

    Article  CAS  Google Scholar 

  35. Liu, D.; Dew, S. K.; Brett, M. J.; Janacek, T.; Smy, T.; and Tsai, W.: Experimental study and computer simulation of collimated sputtering of titanium thin films over topographical features. J. Appl. Phys. 74(2), 1339 (1993)

    Article  CAS  Google Scholar 

  36. Mayo, A. A.; Hamaguchi, S.; Joo, J. H.; and Rossnagel, S. M.: Across-wafer nonuniformity of long throw sputter deposition. J. Vac. Sci. Technol. B 15, 1788 (1997)

    Article  CAS  Google Scholar 

  37. Smy, T.; Tang, L.; Chan, K.; Tait, R. N.; Broughton, J. N.; Dew, S. K.; and Brett, M. J.: A simulation study of long throw sputtering for diffusion barrier deposition into high aspect vias and contacts. IEEE Trans. Electron Devices 45, 1414 (1998)

    Article  CAS  Google Scholar 

  38. Rossnagel, S.; Mikalsen, D.; Kinoshita H.; and Cuomo, J. J.: Collimated magnetron sputter deposition. J. Vac. Sci. Technol. A 9(2), 261 (1991)

    Article  CAS  Google Scholar 

  39. Motegi, N.; Kahimoto, Y.; Nagatani, K.; Takahashi, S.; Kondo, T.; Mizusawa, Y.; and Nakayama, I.: Long-throw low-pressure sputtering technology for very large-scale integrated devices. J. Vac. Sci. Technol. B 13(4), 1906 (1995)

    Article  CAS  Google Scholar 

  40. Broughton, J. N.; Brett, M. J.; Dew, S. K.; and Este, G.: Titanium sputter deposition at low pressures and long throw distances. IEEE Trans. Semiconduct. Manufact. 96, 122 (1996)

    Article  Google Scholar 

  41. Yamashita, M.: Sputter Type High Frequency Ion Source for Ion Beam … Sputtering Apparatus. J. Vac. Sci. Technol. A 7, 151 (1989)

    Article  Google Scholar 

  42. Rossnagel, S. M. and Hopwood, J. H.: Magnetron sputter deposition with levels of metal ionization. Appl. Phys. Lett. 63, 3285 (1993)

    Article  CAS  Google Scholar 

  43. Hamaguchi, S. and Rossnagel, S. M.: Liner conformality in ionized magnetron sputter metal deposition process. J. Vac. Sci. Technol. B 14, 2603 (1996)

    Article  CAS  Google Scholar 

  44. Sugiyama, K.; Pac, S.; Takahashi, Y.; and Motojima, S.: LowTempera-ganometallic. Compounds. J. Electrochem. Soc. 122, 1545 (1975)

    Article  CAS  Google Scholar 

  45. Fix, R.; Gordon, R.; and Hoffman, D.: Chemical vapor deposition of vanadium and tantalum nitride thin films. Chem. Matter. 5, 614 (1993)

    Article  CAS  Google Scholar 

  46. Tsai, M.; Sun, S.; Tsai, C.; Chuan, S.; and Chiu, H.: Comparison of the diffusion barrier properties of chemical-vapor-deposited TaN and sputtered TaN between Cu and Si. J. Appl. Phys. 79(9), 6932 (1996)

    Article  CAS  Google Scholar 

  47. Kim, H.: Atomic layer deposition of metal and nitride thin films: Current research efforts and applications for semiconductor device processing. J. Vac. Sci. Technol. B 21(6), 2231 (2003)

    Article  CAS  Google Scholar 

  48. Krishnamoothy, A.; Chanda, K.; Murarka, S. P.; Ryan, J.; and Ramanath, G.: Self-assembled near-zero-thickness molecular layers as diffusion barriers for Cu metallization. Appl. Phys. Lett. 78(17), 2467 (2001)

    Article  Google Scholar 

  49. Ganesan, P. G.; Gamba, J.; Ellis, A.; Kane, R. S.; and Ramanath, G.: Polyelectrolyte nanolayers as diffusion barriers for Cu metallization. Appl. Phys. Lett. 83(16), 3302 (2003)

    Article  CAS  Google Scholar 

  50. Mikami, N.; Hata, N.; Kikkawa, T.; and Machida, H.: Robust self-assembled monolayer as diffusion barrier for copper metallization. Appl. Phys. Lett. 83(25), 5181 (2003)

    Article  CAS  Google Scholar 

  51. Ding, P. J.; Lanford, W. A.; Hymes, S.; and Murarka, S. P.: Room-temperature continuous-wave operation of a single-layered 1.3 μm quantum dot laser. Appl. Phys. Lett. 75(21), 3267 (1994)

    Google Scholar 

  52. Lanford, W. A.; Ding, P. J.; Wang, W.; Hymes, S.; and Murarka, S. P.: Low-temperature passivation of copper by doping with Al or Mg. Thin Solid Films 62(1–2), 234 (1995)

    Article  Google Scholar 

  53. Smithells Metals Reference Book, 7th Ed., Brandes, E. A.; and Brook, G. B., eds. Butterworth Heinemann (1992)

    Google Scholar 

  54. Frederick, M. J. and Ramanath, G.: Kinetics of interfacial reaction in Cu–Mg alloy films on SiO2. J. Appl. Phys. 95(1), 363 (2004)

    Article  CAS  Google Scholar 

  55. Hino, M.; Nagasaka T.; and Takehama, R.: Activity measurement of the constituents in liquid Cu-Mg and Cu-Ca alloys with mass spectrometry. Metall. Mater. Trans. 31B, 927 (2000)

    CAS  Google Scholar 

  56. Jacob, K. T.; Priya, S.; and Waseda, Y.: A thermodynamic study of liquid Cu-Cr alloys and metastable liquid immiscibility. Z. Metallkd. 91(7), 594 (2000)

    CAS  Google Scholar 

  57. Lewin, K.: Thermodynamic study of the Cu-Mn system. Scan. J. Metall. 22, 310 (1993)

    CAS  Google Scholar 

  58. Oyamada, H.; Nagasaka, T.; and Hino, M.: Activity measurement of the constituents in liquid Cu-Al alloy with mass-spectrometry. Mater. Trans. 12, 1225 (1998)

    Google Scholar 

  59. Witusiewicz, V; Arpshofen, I; and Sommer, F.: Thermodynamics of liquid Cu-Si and Cu-Zr alloys. Z. Metallkd. 91, 594 (2000)

    Google Scholar 

  60. Katayama, I.; Shimatani, H.; and Kouzuka, Z.: Thermodynamic Study of Solid Cu-Ni and Ni-Mo Alloys by E. M. F. Measurements using the solid electrolyte. J. Jpn. Inst. Metall. 37(5), 509 (1973)

    CAS  Google Scholar 

  61. Azakami T. and Yazawa. A.: Activity measurements of liquid copper binary alloys. Can. Metall. Quart. 15, 111 (1976)

    CAS  Google Scholar 

  62. Hondros, E. D. and Seah, M. P.: In Physical Metallurgy. Cahn, R. W. and Haasen, P., Eds. North-Holland, Amsterdam 855 (1983)

    Google Scholar 

  63. Landolt-Bornstein: Numerical Data and Functional Relationships in Science and Technology, New Series, Group III: Crystal and Solid State Physics, Vol. 26, Diffusion in Solid Metals and Alloys, ed. by H. Mehrer, Springer, Berlin, 185 (1990)

    Google Scholar 

  64. Koike, J. and Wada, M.: Self-forming diffusion barrier layer in Cu–Mn alloy metallization. Appl. Phys. Lett. 87(4), 041911 (2005)

    Article  Google Scholar 

  65. Koike, J.; Haneda, M.; Iijima, J.; Otsuka, Y.; Sako, H.; Neishi, K.: Growth kinetics and thermal stability of a self-formed barrier layer at Cu-Mn/SiO2 interface. J. Appl. Phys. 102(4), 043527 (2007)

    Article  Google Scholar 

  66. Usui, T.; Nasu, H.; Takahashi, S.; Shimizu, N.; Nishikawa, T.; Yoshimaru, M.; Shibata, H.; Wada, M.; and Koike, J.: Highly reliable copper dual-damascene interconnects with self-formed MnSixOy barrier Layer. IEEE Trans Electron Devices 53(10), 2492 (2006)

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Materials Science, Tohoku University, 980-8579, Sendai, Japan

    Junichi Koike

Authors
  1. Junichi Koike
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Junichi Koike .

Editor information

Editors and Affiliations

  1. Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel

    Yosi Shacham-Diamand

  2. Dept. Applied Chemistry, Waseda University, Okubo 3-4-1 , Tokyo, 169-8555, Japan

    Tetsuya Osaka

  3. Emerson Network Power, Cooligy Precision Cooling, Maude Avenue 800, Mountain View, 94043, U.S.A.

    Madhav Datta

  4. Division of Corporate Relations, The University of Tokyo, Hongo 7-3-1, Tokyo , 113-8654, Japan

    Takayuki Ohba

Rights and permissions

Reprints and permissions

Copyright information

© 2009 Springer Science+Business Media, LLC

About this chapter

Cite this chapter

Koike, J. (2009). Physical Vapor Deposition Barriers for Cu metallization - PVD Barriers. In: Shacham-Diamand, Y., Osaka , T., Datta, M., Ohba, T. (eds) Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications. Springer, New York, NY. https://doi.org/10.1007/978-0-387-95868-2_21

Download citation

Publish with us

Policies and ethics

Search

Navigation