Comparison of electroplated eutectic Sn/Bi and Pb/Sn solder bumps on various UBM systems

Author

Jang, Se-Young ; Paik, Kyung Wook

Author_Institution

Dept. of Mater. Sci. & Eng., Korea Adv. Inst. of Sci. & Technol., Seoul, South Korea

fYear

2000

fDate

2000

Firstpage

64

Lastpage

68

Abstract

The effect of a reflow process and under bump metallurgy (UBM) systems on the growth of intermetallic compounds for Sn/Bi and Pb/Sn solder bump/UBM interfaces was investigated. The UBM systems were sputtered Al/Ti/Cu, Al/Ti/electroless plated Cu, Al/NiV/sputtered Cu, Al/electroless plated Ni/Au, and the solder bumps were eutectic Pb/Sn and Bi/Sn fabricated by an electroplating method. Microstructure and composition of intermetallic compound (IMC) phases and their morphology were examined using scanning electron microscopy and X-ray diffraction. The IMC compounds were confirmed to be Cu₆Sn₅, Cu ₃Sn, Ni₃Sn₄, or Ni₃Sn depending on UBM and solder types. The effect of IMC growth on bump adhesion strength was also investigated using a ball shear test. It turns out that ball shear strengths of the systems depends not on processing conditions but on solder/UBM interfacial adhesion strength

Keywords

X-ray diffraction; adhesion; bismuth alloys; electroplating; eutectic alloys; flip-chip devices; lead alloys; reflow soldering; scanning electron microscopy; shear strength; tin alloys; Al-Ni-Au; Al-NiV-Cu; Al-Ti-Cu; Pb-Sn; Sn-Bi; X-ray diffraction; ball shear strength; electronic packaging; electroplating; eutectic solder bump; flip-chip interconnection; interfacial adhesion strength; intermetallic compound growth; reflow process; scanning electron microscopy; under bump metallurgy; Adhesives; Bismuth; Gold; Intermetallic; Microstructure; Morphology; Scanning electron microscopy; Testing; Tin; X-ray diffraction;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components & Technology Conference, 2000. 2000 Proceedings. 50th

Conference_Location

Las Vegas, NV

Print_ISBN

0-7803-5908-9

Type

conf

DOI

10.1109/ECTC.2000.853119

Filename

853119