By Topic

Lead-Free Solder Micro-Ball Bumps for the Next Generation of Flip Chip Interconnection: Micro-Ball Materials, Bump Formation Process and Reliability

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Shinji Ishikawa ; Nippon Steel Corporation, Advanced Technology Research Laboratories, 20-1 Shintomi, Futtsu-City, Chiba, 293-8511 Japan. TEL: +81-80-2798, FAX: +81-439-80-2746, E-mail: ; Tomoyuki Uchiyama ; Eiji Hashino ; Taro Kohno
more authors

Micro-ball wafer bumping (MBB) technology, which has capability of fine pitch bumping such as 150-mum pad pitch and the advantages of adjusting the optimum material combinations of joints, was brought into practice. High productivity and yield were achieved by employing an inspection and the repair process with special equipment, and a void-less reflow process was established. Package-level reliability tests were performed for chips with Ti/NiV/Cu-UBM and Sn-Ag-Cu solder bumps using MBB technology with excellent results. An evaluation on reliability was also conducted with Sn-1.2Ag-0.5Cu-Ni solder and pure tin solder bumps. As a result of multiple reflow cycle tests for Ti/NiV/Cu-UBM and various lead-free solders, the shape of IMC and the spalling of IMC were influenced by the total amount of Cu and Ni in the solder and the UBM composition. Ti/NiV/Cu-UBM can be applied to various solders by changing the thickness of the surface Cu layer according to the composition of the solder.

Published in:

2007 Proceedings 57th Electronic Components and Technology Conference

Date of Conference:

May 29 2007-June 1 2007