Electroless CoMoB Diffusion Barrier Layer for ULSI-Cu Metallization

Abstract:

CoMoB film was prepared on Si substrate via electroless deposition as the diffusion barrier for ULSI-Cu metallization. Annealing experiments of CoMoB(30nm) film and CoMoB(10nm)/Cu (40nm)/CoMoB(30nm)/SiO₂/Si multi-films were carried out in the temperature range from 400^◦C to 700^◦C. Failure temperature and mechanism of Cu diffusion in CoMoB film were discussed. The composition, sheet resistance and morphology of the film were investigated by X-Ray Diffractometer (XRD), Four Point Probe (FPP) and Atomic Force Microscopy (AFM), respectively. It can be concluded that the failure temperature of CoMoB film is 600^◦C. The main reason of failure is that a large number of Cu particles passed through CoMoB grain boundary and reacted with Si substrate to generate Cu₄Si with high resistance.

• Periodical: Materials Science Forum (Volume 847)
• Pages: 91-96
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.847.91
• Online since: March 2016
• Authors: Xue Mei Liu*, Xiu Hua Chen, Wen Hui Ma, Yu Ping Li, Ping Bi, Yun Chun Wang, Fu Wei Xiang
• Keywords: CoMoB Thin Films, Electroless Deposition, Failure Mechanism, ULSI-Cu

References

[1] T. Osaka, M. Yoshino, New formation process of plating thin films on several substrates by means of self-assembled monolayer (SAM) process, J. Electrochimica Acta. 53 (2007) 271-277.

DOI: 10.1016/j.electacta.2007.04.004

[2] A. Kumara, M. Kumar, D. Kumar, Effect of composition on electroless deposited Ni-Co-P alloy thin films as a diffusion barrier for copper metallization, J. Applied Surface Science. 258 (2012) 7962-7967.

DOI: 10.1016/j.apsusc.2012.04.145

[3] A. Kumar, M. Kumar, D. Kumar, Deposition and characterization of electroless Ni-Co-P alloy for diffusion barrier applications, J. Microelectronic Engineering. 87 (2010) 387-390.

DOI: 10.1016/j.mee.2009.06.034

[4] J. S. Fang, J. H. Lin, B.Y. Chen, Low resistivity Ru-Ta-C barriers for Cu interconnects, Journal of Electronic Materials 41 (2012) 138-143.

DOI: 10.1007/s11664-011-1797-4

[5] H.J. Luo, B.N. Song, Y.H. Liu, Electroless Ni-P plating on Mg-Li alloy by two-step method, J. Transactions of Nonferrous Metals Society of China. 21 (2011) 2225-2230.

DOI: 10.1016/s1003-6326(11)60999-0

[6] M.L. Wang, Z.G. Yang, C. Zhang, Growing process and reaction mechanism of electroless Ni-Mo-P film on SiO2 substrate, J. Trans. Nonferrous Met. Soc. China. 23 (2013) 3629-3633.

DOI: 10.1016/s1003-6326(13)62910-6

[7] T.K. Tsai, S.S. Wu, C.S. Hsu, Effect of phosphorus on the copper diffusion barrier properties of electroless CoWP films, J. Thin Solid Films. 519 (2011) 4958–4962.

DOI: 10.1016/j.tsf.2011.01.061

[8] R. Tarozaite, Z. Sukackiene, A. Sudavicius, Application of glycine containing solutions for electroless deposition of Co-P and Co-W-P films and their behavior as barrier layers, J. Materials Chemistry and Physics. 117 (2009) 117-124.

DOI: 10.1016/j.matchemphys.2009.05.016

[9] Z. Tokei, Y.L. Li, Reliability challenges for copper low-k dielectrics and copper barrier, J. Microelectronics Reliability. 45 (2005) 1436-1442.

DOI: 10.1016/j.microrel.2005.07.040

[10] S.W. Wei: Study of plating Cu on fine groove (2003).

[11] M. Yoshino, Y. Nonaka, J. Sasano, All-wet fabrication process for ULSI interconnect technologies, J. Electrochimica Acta. 51 (2005) 916-920.

DOI: 10.1016/j.electacta.2005.04.069

[12] Y. Shacham-Diamand, Y. Sverdlov, N. Petrov, Electroless deposition of NiMoP films using alkali-free chemicals for capping layers of copper interconnections, J. Korean Journal of Chemical Engineering 29 (2012) 1259-1265.

DOI: 10.1007/s11814-011-0301-4

[13] S.M.S.I. Dulal, C.B. Shin, J.Y. Sung, Electrodeposition of CoWP film II, Effect of electrolyte concentration, Journal of Applied Electrochemistry. 38 (2008) 83-91.

DOI: 10.1007/s10800-007-9404-3

[14] Y. Sverdlov, V. Bogush, Y. Shacham, Microtructure and material properties of electroless CoWP films obtained from sulfamate solution, J. Microelectronic Engineering. 83 (2006) 2243-2247.

DOI: 10.1016/j.mee.2006.10.012

[15] Z.L. Wang, Z.J. Liu, H.Y. Jang, Electrolessly deposited diffusion barriers for microlectronics, J. Electrochemistry. 12 (1998) 125-133.

[16] N. Osaka Takano, T. Kurokawa, Fabrication of Electroless NiReP Barrier Layer on SiO2 Witllout Sputtered Seed Layer, J. Solid State Letter. 5 (2002) C7～C10.

DOI: 10.1149/1.1421747

[17] N. Osaka Takano, T. Kurokawa, Electroless Nickel Ternary Alloy deposition on SiO2 for application to diffusion barrier layer in copper inter-connect technology, J. Electrochem Soc. 149 (2002) C573～C578.

DOI: 10.1149/1.1512669

[18] M. Hasegawa, Y. Negishi, T. Nakanishi, Effects of additives on copper electrodeposition in submicrometer trenches, J. Electrochem Soc, 152 (2005) C221.

DOI: 10.1149/1.1867672

[19] Y. Shacham-Diamand, Y. Sverdlov, N. Petrov, Electroless deposition of thin film Cobalt-Tungsten—Phosphorus layers using tungsten phosphoric acid(H3[P(W3O10)4]) for ULSI and MEMS applications, J. Electrochem Soc. 148 (2001) C162～C167.

DOI: 10.1149/1.1346605

[20] T.K. Tsai, S.S. Wu, C.S. Hsu, Effect of phosphorus on the copper diffusion barrier properties of electroless CoWP films, J. Thin Solid Films. 519 (2011) 4958-4962.

DOI: 10.1016/j.tsf.2011.01.061