Effect of carbon nanotubes and their dispersion on electroless Ni-P under bump metallization for lead-free solder interconnection

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

16 Scopus Citations
View graph of relations

Author(s)

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)2686-2691
Journal / PublicationJournal of Materials Science: Materials in Electronics
Volume25
Issue number6
Publication statusPublished - Jun 2014

Abstract

Electroless Ni-P under bump metallization (UBM) has advantages of even surface, low cost and simplicity to deposit, but their mechanical strength, corrosion resistance and stability still face challenges under high soldering temperature. Incorporating carbon nanotubes (CNTs) into electroless Ni-P UBM might be expected to provide Ni-P-CNT composites with high mechanical strength and stability. Ni-P-CNT composite coatings as well as Ni-P coatings were fabricated by electroless plating process. In order to homogeneously disperse CNTs in composite coatings, acid pre-treatment and surfactant dispersant were introduced. During composite electroless plating, the ultrasonic agitation was also employed. In this study, scanning electronic microscopy (SEM) was used to observe the morphology and the CNTs were proved to be uniformly distributed in Ni-P-CNT coatings by SEM and atomic force microscopy. It was verified that the surface of the composite was quite smooth and continuous; CNTs are equably embedded in the matrix, which is advantageous for conductivity, mechanical strength and corrosion resistance. Shear tests were conducted to evaluate the effect of CNT reinforcement on the mechanical properties of joints, and the joints with CNT additions exhibited higher shear strength at different reflow cycles. Moreover, deposition mechanism of CNTs with Ni was analyzed and confirmed by transmission electron microscopy. Factors that affecting plating process was also discussed, and the optimum plating condition was suggested in this study. © 2014 Springer Science+Business Media New York.

Citation Format(s)

Effect of carbon nanotubes and their dispersion on electroless Ni-P under bump metallization for lead-free solder interconnection. / Xu, Sha; Hu, Xiao; Yang, Ying; Chen, Zhong; Chan, Yan Cheong.

In: Journal of Materials Science: Materials in Electronics, Vol. 25, No. 6, 06.2014, p. 2686-2691.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review