Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-17T21:23:50.637Z Has data issue: false hasContentIssue false

Elastic anisotropy of Cu and its impact on stress management for 3D IC: Nanoindentation and TCAD simulation study

Published online by Cambridge University Press:  21 October 2011

Kong Boon Yeap*
Affiliation:
Fraunhofer Institute for Nondestructive Testing, 01109 Dresden, Germany
Ehrenfried Zschech
Affiliation:
Fraunhofer Institute for Nondestructive Testing, 01109 Dresden, Germany
Ude D. Hangen
Affiliation:
Hysitron Inc., Minneapolis, Minnesota 55344
Thomas Wyrobek
Affiliation:
Hysitron Inc., Minneapolis, Minnesota 55344
Lay Wai Kong
Affiliation:
State University of New York, College of Nanoscale Science and Engineering, Albany, New York 12203
Aditya Karmakar
Affiliation:
Synopsys Inc., Mountain View, California 94043
Xiaopeng Xu
Affiliation:
Synopsys Inc., Mountain View, California 94043
Iuliana Panchenko
Affiliation:
Technische Universitaet Dresden, Electronics Packaging Laboratory, 01069 Dresden, Germany
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

This article presents a study on elastic anisotropy of Cu by indentations at different penetration depth ranges (sub-10 nm, several-10 nm, and several-100 nm), and the impact of elastic anisotropy on the stress in 3D stacked integrated circuits (3D ICs). The reduced modulus, ER, values determined at sub-10 nm indentations on Cu single crystals are very close to the unidirectional values. Similarly, cross-sectional sub-10 nm indentation tests on the Cu grains in a through-silicon via (TSV) show unidirectional ER values. In contrast, the Hill’s average values are observed at several-100 nm indentations. We propose that before lattice rotation happens within a volume beneath the indentation, elastic anisotropy can be strongly reflected in the ER value. When the experimentally measured Cu elastic anisotropy is used in a technology computer-aided design simulation of a Cu-filled TSV, significant impacts are observed on the stress field and the carrier mobility variation in an active Si region.

Type
Articles
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Wunderle, B., Mrossko, R., Wittler, O., Kaulfersch, E., Ramm, P., Michel, B., and Reichl, H.: Thermo-mechanical reliability of 3D-integrated microstructures in stacked silicon, in Enabling Technologies for 3-D Integration, edited by Bower, C.A., Garrou, P.E., Ramm, P., and Takahashi, K. (Mater. Res. Soc. Symp. Proc., 970, Warrendale, PA, 2007), 0970-Y02-04, p. 67.Google Scholar
2.Karmarkar, A., Xu, X., and Moroz, V.: Performance and reliability analysis of 3D-integration structures employing through silicon via (TSV), in Reliability Physics Symposium (IEEE Proceedings, Montreal, QC, 2009), p. 682.Google Scholar
3.Lu, K.H., Zhang, X.F., Ryu, S.K., Huang, R., and Ho, P.S.: Thermal stress analysis of 3D interconnect, in 10th International Workshop on Stress-Induced Phenomena in Metallization, edited by Zschech, E., Ho, P.S., and Ogawa, S. (AIP Conf. Proc., 1143, Austin, TX, 2009), pp. 224230.Google Scholar
4.Karmarkar, A., Xu, X., Ramaswami, S., Dukovic, J., Sapre, K., and Bhatnagar, A.: Material, process and geometry effects on through-silicon via reliability and isolation, in Advanced Interconnects and Chemical Mechanical Planarization for Micro- and Nanoelectronics, edited by Bartha, J.W., Borst, C.L., DeNardis, D., Rao, S.S.P., Kim, H., Naeemi, Azad, Nelson, A., Ro, H.W., and Toma, D. (Mater. Res. Soc. Symp. Proc. 1249, Warrendale, PA, 2010), 1249-F09-08, p. 323.Google Scholar
5.Sukharev, V., Kteyan, A., Khachetryn, N., Hovsepyan, H., Torres, J.A., Choy, J.H., and Markosian, A.: 3D IC TSV-based technology: Stress assessment for chip performance, in 11th International Workshop on Stress-Induced Phenomena in Metallization, edited by Zschech, E., Ho, P.S., and Ogawa, S. (AIP Conf. Proc., 1300, Bad Schandau, Germany, 2010), p. 202.Google Scholar
6.TCAD Sentaurus Interconnect User Guides and Reference Manuals, Synopsys, Inc., December 2010.Google Scholar
7.Li, H., Randall, N.X., and Vlassak, J.J.: New method of analyzing indentation experiments on very thin films. J. Mater. Res. 25, 728 (2010).CrossRefGoogle Scholar
8.DeBoer, M.P. and Gerberich, W.W.: Microwedge indentation of the thin film fine line. 1. Mechanics. Acta Mater. 44, 3169 (1996).CrossRefGoogle Scholar
9.Yeap, K.B., Zeng, K.Y., and Chi, D.Z.: Determining the interfacial toughness of low-k films on Si substrate by wedge indentation: Further studies. Acta Mater. 56, 997 (2008).CrossRefGoogle Scholar
10.Hill, R.: The elastic behaviour of a crystalline aggregate. Proc. Phys. Soc. A 65, 349 (1952).CrossRefGoogle Scholar
11.Vlassak, J.J. and Nix, W.D.: Indentation modulus of elastically anisotropic half spaces. Philos. Mag. A 67, 1045 (1993).CrossRefGoogle Scholar
12.Kumar, A., Rabe, U., Hirsekorn, S., and Arnold, W.: Elasticity mapping of precipitates in polycrystalline materials using atomic force acoustic microscopy. Appl. Phys. Lett. 92, 183106 (2008).CrossRefGoogle Scholar
13.Vlassak, J.J. and Nix, W.D.: Measuring the elastic properties of anisotropic materials by means of indentation experiment. J. Mech. Phys. Solids 42, 1223 (1994).CrossRefGoogle Scholar
14.Oliver, W.C. and Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 (1992).CrossRefGoogle Scholar
15.Timoshenko, S.P. and Goodier, J.N.: Theory of Elasticity, 3rd ed. (McGraw-Hill, London, 1970), pp. 413.Google Scholar
16.Dub, S.N., Lim, Y.Y., and Chaudhri, M.M.: Nanohardness of high purity Cu (111) single crystals: The effect of indenter load and prior plastic sample strain. J. Appl. Phys. 107, 043510 (2010).CrossRefGoogle Scholar
17.Kiely, J.D. and Houston, J.E.: Nanomechanical properties of Au (111), (001), and (110) surfaces. Phys. Rev. B 57, 12588 (1998).CrossRefGoogle Scholar
18.Wang, W. and Lu, K.: Nanoindentation study on elastic and plastic anisotropies of Cu single crystals. Philos. Mag. 86, 5309 (2006).CrossRefGoogle Scholar
19.Pathak, S., Stojakovic, D., and Kalidindi, S.R.: Measurement of the local mechanical properties in polycrystalline samples using spherical nanoindentation and orientation imaging microscopy. Acta Mater. 57, 3020 (2009).CrossRefGoogle Scholar
20.Sneddon, I.N.: The relation between load and penetration in the axisymmetric Boussinesq problem for a punch of arbitrary profile. Int. J. Eng. Sci. 3, 47 (1965).CrossRefGoogle Scholar
21.Cross, G.L.W., Schirmeisen, A., Grutter, P., and Durig, U.T.: Plasticity, healing and shakedown in sharp-asperity nanoindentation. Nat. Mater. 5, 370 (2006).CrossRefGoogle ScholarPubMed
22.Domnich, V., Gogotsi, Y., and Dub, S.: Effects of phase transformations on the shape of unloading curve in the nanoindentation of silicon. Appl. Phys. Lett. 76, 2214 (2000).CrossRefGoogle Scholar
23.Chudoba, T., Griepentrog, M., Duck, A., Schneider, D., and Richter, F.: Young’s modulus measurements on ultra-thin coatings. J. Mater. Res. 19, 301 (2004).CrossRefGoogle Scholar
24.Yeap, K.B., Hangen, U.D., Raabe, D., and Zschech, E.: Nanoindentation study of elastic anisotropy of Cu single crystals and grains in TSV, in Fraunhofer/Sematech Workshop on Stress Management for 3D ICs Using Through Silicon Vias (AIP Conf. Proc., 1378, Dresden, Germany, 2011).Google Scholar
25.Zaafarani, N., Raabe, D., Singh, R.N., Roters, F., and Zaefferer, S.: Three-dimensional investigation of the texture and microstructure below a nanoindent in a Cu single crystal using 3D EBSD and crystal plasticity finite element simulations. Acta Mater. 54, 1863 (2006).CrossRefGoogle Scholar
26.Ziegenhain, G., Urbassek, H.M., and Hartmaier, A.: Influence of crystal anisotropy on elastic deformation and onset of plasticity in nanoindentation: A simulational study. J. Appl. Phys. 107, 061807 (2010).CrossRefGoogle Scholar
27.Hopcroft, M.A., Nix, W.D., and Kenny, T.W.: What is the Young’s modulus of silicon. J. Microelectromech. 229, 19 (2010).Google Scholar
28.Shen, Y-L.: On the elastic assumption for copper lines in interconnect stress modeling. IEEE Trans. Device Mater. Reliab. 8, 600 (2008).CrossRefGoogle Scholar