@inproceedings{70046ffe3fc84a47b25f7625a8dbb6e9,
title = "Fluxless solder bumping in flip chip package by plasma reflow",
abstract = "A new fluxless reflow process using Ar+10%H2 plasma was investigated for application to solder bump flip chip packaging. The 100 μm-diameter Sn-3.5wt%Ag solder balls were bonded to 250 μm pitch Cu/Ni under bump metallurgy (UBM) pattern by laser solder ball bumping method. Then, the Sn-Ag solder balls were reflowed in Ar+H2 plasma. Without flux, the wetting between solder and UBM occurred in Ar+H2 plasma. During plasma reflow, the solder bump reshaped and the crater on the top of bump disappeared. The bump shear strength increased as the Ni3Sn4 intermetallic compounds formed on initial reflow stage but began to degrease as coarse (Cu,Ni)6Sn5 grew at solder/UBM interface. As the plasma reflow time increased, the fracture within solder bulk decreased and the fracture along solder/UBM interface increased. The off-centered bumps self-aligned to UBM pattern during plasma reflow. The solder ball defect occurred in high power and a long time plasma reflow.",
author = "Hong, {Soon Min} and Kang, {Choon Sik} and Jung, {Jae Pil}",
note = "Publisher Copyright: {\textcopyright} 2001 IEEE.; 3rd International Symposium on Electronic Materials and Packaging, EMAP 2001 ; Conference date: 19-11-2001 Through 22-11-2001",
year = "2001",
doi = "10.1109/EMAP.2001.983973",
language = "English",
series = "Advances in Electronic Materials and Packaging 2001",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "139--144",
editor = "S.B. Lee and K.W. Paik",
booktitle = "Advances in Electronic Materials and Packaging 2001",
address = "United States",
}