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Materials Issues in Copper Interconnections

Published online by Cambridge University Press:  29 November 2013

J.M.E. Harper ,
E.G. Colgan ,
C-K. Hu ,
P. Hummel ,
L.P. Buchwalter  and
C.E. Uzoh
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Extract

Significant progress has been made in building multilevel copper interconnection systems for advanced microelectronics. In this article, we examine some of the materials science issues underlying this progress, and indicate where significant materials challenges remain. It is probable that several approaches to process integration will be developed for copper interconnections, as has been the case with aluminum systems. The first successful demonstration of a fully integrated 4-level copper/polyimide (Cu/PI) interconnection system has been described by Luther et al. of IBM. A schematic cross section of this interconnection system is shown in Figure 1, indicating multiple layers of BPDA-PDA polyimide (PI 5810), Cu lines and studs, and layers of Ta and Si3N4 which serve as diffusion barriers, adhesion layers, and stopping layers in the patterning and planarization processes. This system demonstrates excellent planarity, as shown in the SEM cross section in Figure 2. The electromigration lifetime of this Cu/PI system is greatly improved relative to state-of-the-art aluminum-based systems, and the dielectric integrity appears adequate. Signal propagation studies also confirm the performance improvements anticipated for copper as a low-resistivity conductor and the use of Cu may allow significant capacitance reduction (≃ 25%) simply by scaling Cu lines to equal the resistance of Al lines. In parallel with efforts to introduce Cu metallization for its low resistivity, extensive efforts are under way to replace SiO2 with lower dielectric constant insulators.

Type
Copper Metallization in Industry
Information
MRS Bulletin , Volume 19 , Issue 8 , August 1994 , pp. 23 - 29
Copyright
Copyright © Materials Research Society 1994

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References

1. See the MRS Bulletin XVIII (6) (1993) on Copper Metallization; and Advanced Metallization for ULSI Applications in 1993, edited by D.P. Favreau, Y. Shacham-Diamand, and Y. Horiike (Materials Research Society, Pittsburgh, PA, 1994).Google Scholar
2.Paraszczak, J., Edelstein, D., Cohen, S., Babich, E., and Hummel, J., Proc. Int. Electron Devices Meeting, p. 261 (1993). See also “SIA Semiconductor Technology, An Agenda for American Cooperation,” (Semiconductor Industry Association, 1993).CrossRefGoogle Scholar
3.Luther, B., White, J.E, Uzoh, C., Cacouris, T., Hummel, J., Guthrie, W., Lustig, N., Greco, S., Greco, N., Zuhoski, S., Agnello, P., Colgan, E., Mathad, S., Saraf, L., Weitzman, E.J., Hu, C-K., Kaufman, F., Jaso, M., Buchwalter, L.P., Reynolds, S., Smart, C., Edelstein, D., Baran, E., Cohen, S., Knoedler, C.M., Malinowski, J., Horkans, J., Deligianni, H., Harper, J., Andricacos, P.C., Paraszczak, J., Pearson, D.J., and Small, M., in Proc. IEEE VLSI Multilevel Interconnections Conf., Santa Clara, CA, June 8–9, 1993, p. 15.Google Scholar
4.Edelstein, D., Scheuermann, M., Geppert, L., in Proc. IEEE VLSI Multilevel Interconnections Conf., Santa Clara, CA, June 8–9, 1993; D. Edelstein, Proc. SPIE, Vol. 1389 (1990) p. 352.Google Scholar
5.Handbook of Electrical Resistivities of Binary Metallic Alloys (CRC Press, 1983).Google Scholar
6.Diffusion Phenomena in Thin Films and Microelectronic Materials, edited by Gupta, D. and Ho, P.S. (Noyes Publications, 1988).Google Scholar
7.Mayadas, A.F. and Shatzkes, M., Phys. Rev. B 1 (1970) p. 1382.CrossRefGoogle Scholar
8.Introduction to Solid State Physics, 3rd ed., by Kittel, C. (Wiley and Sons, 1966) p. 217.Google Scholar
9.Krusin-Elbaum, L. and Aboelfotoh, M.O., Appl. Phys. Lett. 58 (1991) p. 1341.CrossRefGoogle Scholar
10.Arcot, B., Cabral, C. Jr., Harper, J.M.E., and Murarka, S.P., in Materials Reliability Issues in Microelectronics, edited by Lloyd, J.R., Yost, F., and Ho, P.S. (Mater. Res. Soc. Symp. Proc. 225, Pittsburgh, PA, 1991) p. 231.Google Scholar
11.Physics of Electronic Conduction in Solids, by Blatt, F. (McGraw-Hill, 1968).Google Scholar
12.Binary Alloy Phase Diagrams, edited by Massalski, T.B. (ASM International, 1990).Google Scholar
13. See the MRS Bulletin XVIII (12) (1993) on Materials Reliability in Microelectronics.Google Scholar
14.Tracy, D.P. and Knorr, D.B., J. Electron. Mater. 22 (1993) p. 611.CrossRefGoogle Scholar
15.Grovenor, C.R.M., Hentzell, H.T.G., and Smith, D.A., Acta Metall. 32 (1984) p. 773.CrossRefGoogle Scholar
16.Harper, J.M.E., Gupta, J., Smith, D.A., Chang, J.W., Holloway, K.L., Cabral, C. Jr., Tracy, D.P., and Knorr, D.B., Appl. Phys. Lett. (1994) submitted.Google Scholar
17.Thompson, C.V., Annu. Rev. Mater. Sci. 20 (1990) p. 245.Google Scholar
18.Knorr, D.B., Tracy, D.P., and Lu, T.M., Textures and Microstructures 14–18 (1991) p. 543.CrossRefGoogle Scholar
19.Rodbell, K.P., Knorr, D.B., and Mis, J.D., J. Electron. Mater. 22 (1993) p. 597.CrossRefGoogle Scholar
20.Gangulee, A. and d'Heurle, F.M., Thin Solid Films 12 (1972) p. 399.CrossRefGoogle Scholar
21.Longworth, H. and Thompson, C.V., J. Appl. Phys. 69 (1991) p. 3929.CrossRefGoogle Scholar
22.Thouless, M.D. and Rodbell, K.P., J. Appl. Phys., in press (1994); C-K. Hu, D. Gupta, and P.S. Ho, Proc. IEEE Multilevel Interconnection Conf. (June 1985) p. 187.Google Scholar
23.Deformation-Mechanism Maps, by Frost, H.J. and Ashby, M.F. (Pergamon Press, 1982).Google Scholar
24.Thouless, M.D., Gupta, J., and Harper, J.M.E., J. Mater. Res. 8 (1993) p. 1845.CrossRefGoogle Scholar
25.Mechanical Metallurgy, by Dieter, G.E. (McGraw-Hill, 1986) p. 236.Google Scholar
26.Sanchez, J.E. and Arzt, E., Scripta Metall. Mater. 27 (1992) p. 285.CrossRefGoogle Scholar
27.Herminghause, S., Boese, D., Yoon, D., Smith, B., Appl. Phys. Lett. 59 (1991) p. 1043; K.G. Sachdev, J.P. Hummel, R.W. Kwong, R.N. Lang, L.L. Linehan, and H.S. Sachdev, U.S. Patent No. 5,115,090 (May 1992).CrossRefGoogle Scholar
28.Allman, B., Proc. 5th Meeting DuPont Symp. HDI and Thin Film Polyimide Technol., Oct. 4, 1993, p. 662.Google Scholar
29.You, L., Yang, G-R., Lang, C-I., Wu, P., Moore, J.A., McDonald, J.F., and Lu, T-M., J. Vac. Sci. Technol. A 11 (6) (1993) p. 3047.CrossRefGoogle Scholar
30.Polymer Handbook, 2nd ed., edited by Brandrup, J. and Immergut, E.H. (Wiley & Sons, New York, 1975) p. V–31.Google Scholar
31.Burdeaux, D., Townsend, D., Carr, J., and Garrou, P., J. Electron. Mater. 19 (1990) p. 1357.CrossRefGoogle Scholar
32.Hedrick, J., Labadie, J., Russell, T., Hofer, D., and Wakharker, V., Polym. 34 (1993) p. 4717.CrossRefGoogle Scholar
33.Gelatos, A.V., Mogab, C.J., Saha, N.C., and Parikh, N., in Advanced Metallization and Processing for Semiconductor Devices and Circuits II, edited by Katz, A., Nissim, Y.I., Murarka, S.P., and Harper, J.M.E. (Mater. Res. Soc. Symp. Proc. 260, Pittsburgh, PA) p. 347.Google Scholar
34.Allman, D.D.J., Fuchs, K.P., and Kurong, D.L., Proc. IEEE VLSI Multilevel Interconnection Conference, June 11, 1991, p. 373.Google Scholar
35.Usami, T., Shimakawa, K., and Yoshimaru, M., Jpn. J. Appl. Phys. 1, Regular Paper Short Notes, Vol. 33 (1B) (1994) p. 408.CrossRefGoogle Scholar
36.Ginsburg, R. and Susko, J., IBM J. Res. Dev. V28 (1984) p. 1184.Google Scholar
37.Schwartz, G.C., J. Electrochem. Soc. 138 (1991) p. 622.CrossRefGoogle Scholar
38.Chen, S.T. and Wagner, H.H., J. Electron. Mater. 22 (1993) p. 797.CrossRefGoogle Scholar
39.Lacombe, R.H., Buchwalter, L.P., and Holloway, K., J. Adhesion Sci. Technol. 7 (1993) p. 1293.CrossRefGoogle Scholar
40.Kanninen, M.F. and Popelar, C.H., Advanced Fracture Mechanics (Oxford University Press, New York, 1985).Google Scholar
41.Kim, K.S. and Aravas, N., Int. J. Solids Structures 24 (1988) p. 417.CrossRefGoogle Scholar
42.Buchwalter, L.P., J. Adhesion Sci. Technol. 7 (1993) p. 941.CrossRefGoogle Scholar
43.Cho, J.S.H., Kang, H.K., Wong, S., and Shacham-Diamand, Y., MRS Bulletin XVIII (6) (1993) p. 31.CrossRefGoogle Scholar
44.Stolt, L., Charai, A., d'Heurle, F.M., Fryer, P.M., and Harper, J.M.E., J. Vac. Sci. Technol. A9 (1991) p. 1501.CrossRefGoogle Scholar
45.Harper, J.M.E., Charai, A., Stolt, L., d'Heurle, F.M., and Fryer, P.M., Appl. Phys. Lett. 56 (1990) p. 2519.CrossRefGoogle Scholar
46.Hu, C-K., Chang, S., Small, M.B., and Lewis, J.E., Proc. 3rd IEEE VLSI Multilevel Interconnection Conference (1986) p. 181; C.A. Chang and C.K. Hu, Appl. Phys. Lett. 57 (1990) p. 617.Google Scholar
47.Wang, S.Q., in Advanced Metallization for ULSI Applications in 1993, edited by Favreau, D.P., Shacham-Diamand, Y., and Horiike, Y. (Materials Research Society, Pittsburgh, PA, 1994) p. 31.Google Scholar
48.Kolawa, E., Molarius, J.M., Nieh, C.W., and Nicolet, M-A., J. Vac. Sci. Technol. A8 (1990) p. 3006.CrossRefGoogle Scholar
49.Nicolet, M-A., Thin Solid Films 52 (1978) p. 415.CrossRefGoogle Scholar
50.Harper, J.M.E., Hörnström, S.E., Thomas, O., Charai, A., and Krusin-Elbaum, L., J. Vac. Sci. Technol. A 7 (1989) p. 875.CrossRefGoogle Scholar
51.Clevenger, L.A., Bojarczuk, N.A., Holloway, K., Harper, J.M.E., Cabral, C. Jr., Schad, R.G., Cardone, F., and Stolt, L., J. Appl. Phys. 73 (1992) p. 300.CrossRefGoogle Scholar
52.Colgan, E.G. and Gambino, J.P., unpublished.Google Scholar
53.Hu, C-K., Pearson, D., and Small, M.B., IBM Tech. Discl. Bull. 32 (7) (1989) p. 47.Google Scholar
54.Harper, J.M.E., Holloway, K.L., and Kwok, T.Y., U.S. Patent No. 5,130,274 (July 1992).Google Scholar
55.Cabral, C. Jr., Holloway, K., Harper, J.M.E., Smith, D.A., and Schad, R., J. Vac. Sci. Technol. A 10 (1992) p. 1706.CrossRefGoogle Scholar
56.Itow, H., Nakasaki, Y., Minamihaba, G., Suguro, K., and Okano, H., Appl. Phys. Lett. 63 (1993) p. 934.CrossRefGoogle Scholar
57.Li, J., Mayer, J.W., Schacham-Diamand, Y., and Colgan, E.G., Appl. Phys. Lett. 60 (1992) p. 2983.CrossRefGoogle Scholar
58.Linde, H. and Gleason, R.T., J. Polym. Sci., Polym. Chem. Ed. 22 (1987) p. 3043.CrossRefGoogle Scholar
59.Colgan, E.G. and Chapple-Sokol, J.D., J. Vac. Sci. Technol. B 10 (3) (1992) p. 1156; E.G. Colgan, unpublished.CrossRefGoogle Scholar