Title :
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
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;
Conference_Titel :
Electronic Components & Technology Conference, 2000. 2000 Proceedings. 50th
Conference_Location :
Las Vegas, NV
Print_ISBN :
0-7803-5908-9
DOI :
10.1109/ECTC.2000.853119