Investigating the Performance of Amorphous W / WN Bilayer as a Cu Diffusion Barrier in Si

مهندسی متالورژی و مواد

Volume 35, Issue 1 - Serial Number 33, April 2024, Pages 51-64   

Document Type: Original Articles

DOI: 10.22067/jmme.2024.79637.1085

Authors

somayeh Asgary^* ; amir hoshang ramezani

Department of Physics, Islamic Azad University, West Tehran Branch, Tehran, Iran.

Abstract

Tungsten/tungsten nitride bilayer with amorphous structure was deposited on the silicon / silicon oxide substrate by high vacuum thermal evaporation method. To investigate the thermal stability of this bilayer as a diffusion barrier layer, the Cu/W /WN/SiO2/Si multilayer was heated at different temperatures and the results were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and four-point probe (FPP) methods. According to the XRD results, formation of the cupper silicide at 800° C indicates diffusion of copper from the W/WN bilayer in the Si. The formation of a Cu3Si with insulation phase leads to a sudden increase in electrical resistance (212 Ω /cm2) and will disrupt the performance of the W/WN barrier layer as a diffusion barrier. The diffusion of copper into silicon is often through undesirable grain boundaries that occur during the heating treatment of the W/ WN bilayer by changing its phase from amorphous to polycrystalline and shown in X-ray diffraction results. At high temperatures, the electron microscope image has shown fracture, cracking and flaking of the surface of the copper layer, which is caused by thermal stress between the penetration barrier/copper surfaces or the volume of the layers.

Keywords

Diffusion barrier layer; Grain boundary diffusion; Cu3Si; WN/W

References

[1]    G. Beyer, A. Satta, J. Schuhmacher, K. Maex, W. Besling, O. Kilpela, H. Sprey, and G. Tempel, “Development of sub-10-nm atomic layer deposition barriers for Cu/low-k interconnects”, Microelectronic Engineering, vol. 64, no.1-4, pp. 233-245, 2002. https://doi.org/10.1016/S0167-9317(02)00795-5

[2]   Z. Li, Y. Tian, C. Teng, C. Teng, and H. Cao, “Recent Advances in Barrier Layer of Cu Interconnects”, Materials, vol. 13, no. 21, pp. 5049, 2020. https://doi.org/10.3390%2Fma13215049

 [3] S. P. Murarka, and S. W.Hymes, “Copper metallization for ULSL and beyond”, Critical Reviews in Solid State and Materials Sciences, vol. 20, no. 2, pp. 87-124, 1995. https://doi.org/10.1080/10408439508243732

[4]   A. E. Kaloyeros, and E. Eisenbraun, “Ultrathin Diffusion Barriers/Liners for Gigascale Copper Metallization”, Annual Review of Materials Science, vol. 30, pp. 363-385, 2000. https://doi.org/10.1146/annurev.matsci.30.1.363

[5]   S. Armini, and P. M. Vereecken, “Impact of Terminal Effect on Cu Plating: Theory and Experimental Evidence”, ECS Trans, vol. 25, no. 27, pp. 185, 2010. DOI:10.1149/1.3318517

[6]   J. S. Fang, T. P. Hsu, and G. S. Chen, “Crystallization and failure behavior of Ta-TM (TM=Fe, Co) nanostructured/amorphous diffusion barriers for copper metallization”, Journal of Electronic Materials, vol. 35, no.1, pp. 15-21, 2006.https://doi.org/10.1007/s11664-006-0178-x

[7]   J. W. Choi, O. L. Guan, Y. J. Mao, H. B. M. Yusoff, J. L. Xie, C. C. Lan, W. L. Loh, B. L. Lau, L. L. H. Hong, L. G. Kian, and R. Murthy, “TSV Cu Filling Failure Modes and Mechanisms Causing the Failures”, IEEE Trans. Comp. Pack. Man. vol. 4, no. 4, pp. 581–587, 2014. https://doi.org/10.1109/TCPMT.2014.2298031

[8]   K. Motoyama, O. V. D. Straten, J. Maniscalco, and M. He, “PVD Cu Reflow Seed Process Optimization for Defect Reduction in Nanoscale Cu/Low-k Dual Damascene Interconnects”, J. Electrochem. Soc. vol. 160, no. 12, 2013.

[9]   J. P. Jacquemin, E. Labonne, C. Yalicheff, E. Royet, P. Vannier, R. Delsol, and P. Normandon, “TaN/Ta bilayer barrier characteristics and integration for 90 and 65 nm nodes”, Microelectronic Engineering, vol. 82, no.3-4, pp. 613-617, 2005. https://doi.org/10.1016/j.mee.2005.07.065

[10] K. Dittmar, H. J. Engelmann, M. E. Peikert, Wieser, and J. V. Borany, “Investigation of ultrathin tantalum based diffusion barrier films using AES and TEM”, Applied Surface Science, vol. 252, no. 1, pp. 185-188, 2005.

[11] D. J. Kim, Y. B. Jung, M. B. Lee, Y. H. Lee, and J. H. Lee, “Applicability of ALE TiN films as Cu/Si diffusion barriers”, Thin Solid Film, vol. 372, no.1-2, pp. 276-283, 2000. https://doi.org/10.1016/S0040-6090(00)01049-X

[12] A. Paranjpe, R. Bubber, L. Velo, G. Shang, S. Gopinath, J. Dalton, M. Moslehi, “CVD TaN barrier for copper metallization and DRAM bottom electrode”, IEEE International Interconnect Technology Conference proceedings, pp. 119-121, 1999. https://doi.org/10.1109/IITC.1999.787096

[13] R. Panwar, and A. Dhingra, “STUDY OF THERMAL STABILITY BEHAVIOR OF MON & WN THIN FILMS IN ULSI”, International Journal of Advances in Engineering & Technology, pp. 55-64, 2011.

[14] Ch. Kuo, Y. Chang, T. Huang, Ya, I. Ch. Ni, M.H. Chen, and Ch. I. Wu, “MoS2 as an Effective Cu Diffusion Barrier with a Back-End Compatible Process”, ACS Appl. Mater. Interfaces, vol. 15, no. 40, pp. 47845–47854, 2023. https://doi.org/10.1021/acsami.3c12267

[15] V. T. Laurila, K. Zeng, J. Molarius, T. Riekkinen, I. Suni, and J. K. Kivilahti, “Tantalum Carbide and Nitride Diffusion Barriers for Cu Metallisation”, Microelectronics Engineering, vol. 60, no. 1-2, pp. 71-80, 2001. https://doi.org/10.1016/S0167-9317(01)00582-2

[16] Y. Ezer, J. Haérkoénen, S. Arpiainen, V. Sokolov, P. Kuivalainen, J. Saarilahti, and J.  Kaitila, “Diffusion Barrier Performance of thin Cr Films in the Cu/Cr/Si Structure”, Physica Scripta, vol. 1999, no. T79, pp. 228-231, 1999.

[17] Y. Zhao, G. Lu, “First-principles simulations of copper diffusion in tantalum and tantalum nitride”, Physics Review B, vol. 79, no. 21, 2009. https://doi.org/10.1103/PhysRevB.79.214104

[18] J. S. An, Y. Kwon, J. S. Oh, Ch. Choi, H. Kim, M. Lee, S. Pae, and Ch. W. Yang, “Characteristics of an Amorphous Carbon Layer as a Diffusion Barrier for an Advanced Copper Interconnect”, ACS Applied Materials & Interfaces, vol. 12, no. 2, pp. 3104-3113, 2019. https://doi.org/10.1021/acsami.9b15562

[19] Y. H. Shin, and Y. Shimogaki, “Diffusion barrier property of TiN and TiN/ Al/TiN films deposited with FMCVD for Cu interconnection in ULSI”, Science and Technology of Advanced Materials, vol. 5, no. 4, pp. 399-405, 2004. https://doi.org/10.1016/j.stam.2004.02.001

[20] Sh. H. Hsieh, W. J. Chen, and Ch.M. Chien, “Structural Stability of Diffusion Barriers in Cu/Ru/MgO/Ta/Si”, Nanomaterials, vol. 5, no. 4, pp. 1840-1852, 2015. https://doi.org/10.3390/nano5041840

[21] Ch. L. Lo, M. Catalano, K. K. H. Smithe, L. Wang, Sh. Zhang, E. Pop, M.J. Kim, and Zh. Chen, “Studies of two-dimensional h-BN and MoS₂ for potential diffusion barrier application in copper interconnect technology”, npj 2D Materials and Applications, vol. 1, no. 42, 2017.  https://doi.org/10.1038/s41699-017-0044-0

[22] L. Li, X. Chen, C. H. Wang, J. Cao, S. Lee, A. Tang, C. Ahn, S. S. Roy, M. S. Arnold, and H. S. P. Wong, “Vertical and lateral copper transport through graphene layers”, ACS Nano, vol. 9, no. 8, pp. 8361–8367, 2015. https://doi.org/10.1021/acsnano.5b03038

[23] B. S. An, Y. Kwon, S. J. Oh, M. Lee, S. Pae, and C. H. W. Yang, “Amorphous TaxMnyOz Layer as a Difusion Barrier for Advanced Copper Interconnects”, Scientific Reports, vol. 27, no. 9, pp. 20132, 2019. https://doi.org/10.1038/s41598-019-56796-y

[24] J. H. Bong, S. J. Yoon, A.Yoon, W. S. Hwang, and B. J. Cho, “Ultrathin graphene and graphene oxide layers as a diffusion barrier for advanced Cu metallization”, Applied Physics Letters, vol. 106, no. 6, 2015. https://doi.org/10.1063/1.4908559

[25] M. Wittmer, “Effect of Cu on the Kinetics and Microstructure of Al₃Ti Formation”, Journal of the Electrochemical Society, vol. 132, pp. 1450, 1985. https://doi.org/10.1149/1.2114142

[26] R. Cheung, J. Klein, K. Tsubouchi, M. Murakami, N. Kobayashi, Materials Research Society, Bahman 12, 1378 AP - Technology & Engineering - 765 pages.

[27] Y. G. Shen, Y. W. Mai, D. R. McKenzie, Q. C. Zhang, W. D. McFall, and W. E. McBride, “Composition, residual stress, and structural properties of thin tungsten nitride films deposited by reactive magnetron sputtering”, Journal of Applied Physics, vol. 88, pp. 1380-1388, 2000. https://doi.org/10.1063/1.373827

[28]  W. Qingxiang, L. Shuhua, W. Xianhui, and F. Zhikang, “Diffusion barrier performance of amorphous W–Ti–N films in Cu metallization”, Vacuum, vol. 84, no. 11, pp. 1270-1274, 2010. https://doi.org/10.1016/j.vacuum.2010.02.002

[29] Frank R. Boer, “Cohesion in Metals: Transition Metal Alloys", North-Holland, Amsterdam, 1988.

[30]        S. Wang, S. Suthar, C. Hoeflich, and B. J. Burrow, “Diffusion barrier properties of TiW between Si and Cu”, Journal of Applied Physics, Vol. 73, pp. 2301–2320, 1993. https://doi.org/10.1063/1.353135

[31] Von L. E. Toth, Transition Metal Carbides and Nitrides. Academic Press, New York–London 1971.

[32] M. Moriyama, T. Kawazoe, M. T. Anaka, and M. Murakami, “Correlation between microstructure and barrier properties of TiN thin films used Cu interconnects”, Thin Solid Films, vol. 416, no. 1-2, pp. 136-144, 2002.  https://doi.org/10.1016/S0040-6090(02)00602-8

[33] W. Schlemminger, and D. Stark, “The influence of deposition temperature on the electrical resistance of thin Cu films”, Surface Science, vol. 189-190, pp. 1103-1110, 1987. https://doi.org/10.1016/S0039-6028(87)80556-3

[34]  P. J. Sadashivaiah, T. Sankarappa, T. Sujatha, M. Santoshkumar, R. Rawat, P. Sarvanan, and A.K. Bhatnagar, “Structural, magnetic and electrical properties of Fe/Cu/Fe films”, Vacuum, vol. 85, no. 3, pp. 466-473, 2010. https://doi.org/10.1016/j.vacuum.2010.08.024

[35] D. Chaverri, S. Alejandro, and V. Castano, “Grain size and electrical resistivity measurements on aluminum polycrystalline thin films”, Materials Letters, vol. 12, no. 5, pp. 344-348, 1991. https://doi.org/10.1016/0167-577X(91)90114-L

[36] W. T. Tseng, Y. L. Wang, and J. Niu, “Microstructure-related resistivity change after chemical-mechanical polish of Al and W thin films”, Thin Solid Films, vol. 370, no. 1-2, pp. 96-100, 2000. https://doi.org/10.1016/S0040-6090(00)00941-X

[37] M. Wen, Q. N. Meng, W. X. Yu, W. T. Zheng, S. X. Mao, and M. J. Hua, “Growth, stress and hardness of reactively sputtered tungsten nitride thin films”, Surface & Coatings Technology, vol. 205, no. 7, pp. 1953-1961, 2010. https://doi.org/10.1016/j.surfcoat.2010.08.082

[38] O. M. Artamonov, S. N. Samarin, and J. F. Williams, “Electron screening and electron–electron scattering mechanisms”, journal of Electron Spectroscopy and Related Phenomena, vol. 191, pp. 79-85, 2013. https://doi.org/10.1016/j.elspec.2013.11.005