Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지
DOI QR코드

DOI QR Code

Effect of B and W Contents on Hardness of Electroless Co Alloy Thin Films

B와 W의 함량이 무전해 Co 합금 박막의 경도에 미치는 영향 연구

  • Lim, Taeho (Department of Chemical Engineering, Soongsil University) ;
  • Kim, Jae Jeong (Institute of Chemical Process, Seoul National University)
  • 임태호 (숭실대학교 화학공학과) ;
  • 김재정 (서울대학교 화학공정신기술연구소)
  • Received : 2018.09.03
  • Accepted : 2018.10.04
  • Published : 2018.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, the electroless deposition of Co-B and Co-W-B alloy thin films was developed and the effect of B and W contents on the hardness of the alloy thin films were investigated. An amorphous Co alloy film was successfully formed by electroless deposition and the contents of B and W in the film were controlled by varying the concentrations of dimethylamine borane and sodium tungstate dihydrate, which were used as a reducing agent and W source, respectively. The hardness of the thin films increased as the contents of B and W were increased because B and W act as impurities suppressing the propagation of dislocation in a film. In addition, it was found that the content of B and W in the Co alloy films can be increased significantly when aeration is not performed. Finally, the hardness of Co-W-B alloy thin film was improved up to 8.9 (${\pm}0.3$) GPa.

본 연구에서는 Co-B, Co-W-B 합금 박막 형성을 위한 무전해 전착법을 고안하고, 이를 통해 형성한 합금 박막의 B과 W의 함량이 박막의 경도에 미치는 영향을 살펴보았다. 무전해 전착을 통해 무정형 상태의 Co 합금 박막을 성공적으로 형성할 수 있었으며, 환원제인 dimethylamine borane과 W의 원료인 sodium tungstate dihydrate의 농도를 조절함으로써 Co 합금 박막 내 혼합되는 B과 W의 함량을 조절하였다. 이를 통해 Co 합금 박막 내 전위(dislocation)의 전파(propagation)를 억제하는 B과 W의 함량이 증가할수록 박막의 경도가 증가함을 확인할 수 있었다. 뿐만 아니라, 무전해 전착 시 포기(aeration)를 수행하지 않을 경우에 포기를 수행한 경우보다 Co 합금 박막 내 B과 W의 함량을 대폭 증가시킬 수 있었고 최종적으로 Co-W-B 합금 박막의 경도를 8.9 (${\pm}0.3$) GPa까지 향상시켰다.

Keywords

HHGHHL_2018_v56n6_895_f0001.png 이미지

Fig. 4. (a) Electroless deposition rate and (b) surface morphologies of 300-nm-thick Co-W-B alloy films according to the concentration of sodium tungstate dihydrate. Insets in Fig. 4(b) are cross-sectional SEM images of 300-nm-thick Co-W-B alloy films. The concentration of DMAB was 13 mM. The deposition times were 23 min, 30 min, 30 min, and 37 min for 7 mM, 15 mM, 30 mM, and 60 mM Na2WO4·2H2O, respectively.

HHGHHL_2018_v56n6_895_f0002.png 이미지

Fig. 6. Change in electroless deposition rate with and without aeration. Inset is the surface SEM image of the Co-W-B alloy film deposited at 13 mM DMAB and 7 mM sodium tungstate dihydrate.

HHGHHL_2018_v56n6_895_f0003.png 이미지

Fig. 7. Changes in (a) B and W contents and (b) Co-W-B alloy film hardness according to aeration status. The concentrations of DMAB and sodium tungstate dihydrate were 13 mM and 7 mM, respectively.

HHGHHL_2018_v56n6_895_f0004.png 이미지

Fig. 1. (a) Electroless deposition rate and (b) surface morphologies of 300-nm-thick Co-B alloy films according to the concentration of DMAB. Insets in Fig. 1(b) are cross-sectional SEM images of 300-nm-thick Co-B alloy films. The deposition times were 25 min, 23 min, 17 min, and 10 min for 13 mM, 25 mM, 50 mM, and 100 mM DMAB, respectively.

HHGHHL_2018_v56n6_895_f0005.png 이미지

Fig. 2. (a) X-ray diffraction patterns of the Co-B alloy films deposited at different concentration of DMAB and (b) cross-sectional TEM image of the Co-B alloy film deposited at 13 mM DMAB. Insets in Fig. 2(b) are SAED pattern and magnified image of the dashed box.

HHGHHL_2018_v56n6_895_f0006.png 이미지

Fig. 3. (a) B content and (b) Co-B alloy film hardness according to the concentration of DMAB.

HHGHHL_2018_v56n6_895_f0007.png 이미지

Fig. 5. Changes in (a) B and W contents and (b) Co-W-B alloy film hardness according to the concentration of sodium tungstate dihydrate. The concentration of DMAB was 13 mM.

References

  1. Martinez-Hernandez, A., Meas, Y., Perez-Bueno, J. J., Ortiz-Frade, L. A., Flores-Segura, J. C., Mendez-Albores, A. and Trejo, G., "Electrodeposition of Co-B Hard Coatings: Characterization and Tribological Properties," Int. J. Electrochem. Sci., 12, 1863-1873(2017).
  2. Pillai, A. M., Rajendra, A. and Sharma, A. K., "Electrodeposited Nickel-phosphorus (Ni-P) Alloy Coating: An In-depth Study of Its Preparation, Properties, and Structural Transitions," J. Coat. Technol. Res., 9(6), 785-797(2012). https://doi.org/10.1007/s11998-012-9411-0
  3. Winowlin Jappes, J. T., Ramamoorthy, and B., Kesavan Nair, P., "A Study on the Influence of Process Parameters on Efficiency and Crystallinity of Electroless Ni-P Deposits," J. Mater. Process. Technol., 169, 308-313(2005). https://doi.org/10.1016/j.jmatprotec.2005.03.010
  4. Krishnaveni, K., Sankara Narayanan, T. S. N. and Seshadri, S. K., "Electroless Ni-B Coatings: Preparation and Evaluation of Hardness and Wear Resistance," Surf. Coat. Technol., 190, 115-121 (2005). https://doi.org/10.1016/j.surfcoat.2004.01.038
  5. Bangwei, Z., Wangyu, Hu., Qinglong, Z. and Xuanyuan, Qu., "Properties of Electroless Ni-W-P Amorphous Alloys," Mater. Charact., 37, 119-122(1996). https://doi.org/10.1016/S1044-5803(96)00089-7
  6. Jin, Z.-Y., Li, P.-P., Zheng, B.-Z. and Xiao, D., "The Structure and Properties of Electroless Ni-Mo-Cr-P Coatings on Copper Alloy," Mater. Corros., 64(4), 341-346(2013). https://doi.org/10.1002/maco.201106289
  7. Park, H. J., Oh, E. K., Kim, S.-G. and Yeu, T., "Electroless Nickel Plating on Alumina Powders," Korean Chem. Eng. Res., 32(3), 358-366(1994).
  8. Nakano, H., Itabashi, T. and Akahoshi, H., "Electroless Deposited Cobalt-tungsten-boron Capping Barrier Metal on Damascene Copper Interconnection," J. Electrochem. Soc., 152(3), C163-C166(2005). https://doi.org/10.1149/1.1860512
  9. Lim, T., Koo, H.-C., Kim, K. H., Park, K. J., Kim, M. J., Kwon, O. J. and Kim, J. J., "Room-temperature Electroless Deposition of CoB Film and Its Application as in situ Capping During Buffing Process," Electrochem. Solid-State Lett., 14(9), D95-D98(2011). https://doi.org/10.1149/1.3600759
  10. Goel, V., Anderson, P., Hall, J., Robinson, F. and Bohm, S., "Electro-less Co-P Carbon Nanotube Composite Coating to Enhance Magnetic Properties of Grain-oriented Electrical Steel," J. Magn. Magn. Mater., 407, 42-45(2016). https://doi.org/10.1016/j.jmmm.2015.12.076
  11. Younan, M. M., Aly, I. H. M. and Nageeb, M. T., "Effect of Heat Treatment on Electroless Ternary Nickel-cobalt-phosphorus Alloy," J. Appl. Elechem., 32, 439-446(2002).
  12. Wang, S.-L., "Electroless Deposition of Ni-Co-B Alloy Films and Influence of Heat Treatment on the Structure and the Magnetic Performances of the Film," Thin Solid Films, 515, 8419-8423(2007). https://doi.org/10.1016/j.tsf.2007.05.066
  13. Samsonov, G. V., Handbook of the physicochemical properties of the elements, 2nd ed., Plenum Publishing Corporation, New York, NY(1968).
  14. Einati, H., Bogush, V., Sverdlov, Y., Rosenberg, Y. and Shacham-Diamand, Y., "The Effect of Tungsten and Boron on the Cu Barrier and Oxidation Properties of Thin Electroless Cobalt-tungsten-boron Films," Microelectron. Eng., 82, 623-628(2005). https://doi.org/10.1016/j.mee.2005.07.082
  15. Ofek Almog, R., Sverdlov, Y., Goldfarb, I. and Shacham-Diamand, Y., "CoWBP Capping Barrier Layer for sub 90 nm Cu Interconnects," Microelectron. Eng., 84, 2450-2454(2007). https://doi.org/10.1016/j.mee.2007.05.031
  16. Kim, T. H., Yun, H. J. and Kim, C.-K, "Electroless Plating of Co-alloy Thin Films Using Alkali-free Chemicals," Korean Chem. Eng. Res., 45(6), 633-637(2007).
  17. Homma, T., Tamaki, A., Nakai, H. and Osaka, T., "Molecular Orbital Study on the Reaction Process of Dimethylamine Borane as a Reductant for Electroless Deposition," J. Electroanal. Chem., 559, 131-136(2003). https://doi.org/10.1016/S0022-0728(03)00042-1
  18. Saito, T., Sato, E., Matsuoka, M. and Iwakura, C., "Electroless Deposition of Ni-B, Co-B and Ni-Co-B Alloys Using Dimethylamineborane as a Reducing Agent," J. Appl. Elechem., 28, 559-563(1998).
  19. Hu, B., Sun, R., Yu, G., Liu, L., Xie, Z., He, X. and Zhang, X., "Effect of Bath pH and Stabilizer on Electroless Nickel Plating of Magnesium Alloys," Surf. Coat. Technol., 228, 84-91(2013). https://doi.org/10.1016/j.surfcoat.2013.04.011
  20. Meyers, M. A., Mishra, A. and Benson, D. J., "Mechanical Properties of Nanocrystalline Materials," Prog. Mater. Sci., 51(4), 427-556(2006). https://doi.org/10.1016/j.pmatsci.2005.08.003
  21. Vaz, F., Ferreira, J., Ribeiro, E., Rebouta, L., Lanceros-Mendez, S., Mendes, J. A., Alves, E., Goudeau, Ph., Riviere, J. P., Ribeiro, F., Moutinho, I., Pischow, K. and de Rijk, J., "Influence of Nitrogen Content on the Structural, Mechanical and Electrical Properties of TiN Thin Films," Surf. Coat. Technol., 191, 317-323(2005). https://doi.org/10.1016/j.surfcoat.2004.01.033
  22. Jiang, W.-G., Su, J.-J. and Feng, X.-Q., "Effect of Surface Roughness on Nanoindentation Test of Thin Films," Eng. Fract. Mech., 75, 4965-4972(2008). https://doi.org/10.1016/j.engfracmech.2008.06.016
  23. Walter, C., Antretter, T., Daniel, R. and Mitterer, C., "Finite Element Simulation of the Effect of Surface Roughness on Nanoindentation of Thin Films with Spherical Indenters," Surf. Coat. Technol., 202, 1103-1107(2007). https://doi.org/10.1016/j.surfcoat.2007.07.038
  24. Severdlov, Y., Bogush, V., Einati, H. and Shacham-Diamand, Y., "Electrochemical Study of the Electroless Deposition of Co(W, B) Alloys," J. Electrochem. Soc., 152(9), C631-C638(2005). https://doi.org/10.1149/1.1997167
  25. Hanna, F., Hamid, A. and Abdel Aal, A., "Controlling Factors Affecting the Stability and Rate of Electroless Copper Plating," Mater. Lett., 58, 104-109(2003).

Cited by

  1. Electrodeposition of Co-B/SiC Composite Coatings: Characterization and Evaluation of Wear Volume and Hardness vol.9, pp.4, 2019, https://doi.org/10.3390/coatings9040279