THE EFFECTS OF COPPER CONTENT ON THE RELIABILITY OF Sn-Ag BASED BUMP ALLOYS IN FLIP CHIP APPLICATIONSAuthor: Shing Yeh
Company: Delphi Delco Electronics
Date Published: 9/22/2002 Conference: SMTA International
Excellent results were observed in wafer bump fabrication and assembly of die to various types of substrates for all four alloys given a single set of process parameters optimized for the melting temperature range of eutectic SnAgCu alloy. A series of reliability tests, including thermal cycling, HTS (High Temperature Storage), and HTOL (High Temperature Operating Life) tests, were conducted with these near eutectic SnAgCu bumps to determine the impact of copper concentration on flip chip reliability.
The copper concentration in the SnAgCu alloys was found to have a significant impact on the reliability of the flip chip bumps, particularly when diffusion related failure mechanisms were involved. Bump reliability increased substantially with increasing copper concentration in HTOL and HTS tests. However, the thermal fatigue lives of the SnAgCu bumps were not sensitive to copper concentration.
Key words: Pb-free, SnAgCu, flip chip, reliability, electromigration.
Members download articles for free:
Not a member yet?
What else do you get when you join SMTA? Read about all of the benefits that go along with membership.
Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.