No-flow underfill flip chip assembly--an experimental and modeling analysis

In the flip-chip assembly process, no-flow underfill materials have a particular advantage over traditional underfill: the application and curing of the former can be undertaken before and during the reflow process. This advantage can be exploited to increase the flip-chip manufacturing throughput. However, adopting a no-flow underfill process may introduce reliability issues such as underfill entrapment, delamination at interfaces between underfill and other materials, and lower solder joint fatigue life. This paper presents an analysis on the assembly and the reliability of flip-chips with no-flow underfill. The methodology adopted in the work is a combination of experimental and computer-modeling methods. Two types of no-flow underfill materials have been used for the flip chips. The samples have been inspected with X-ray and scanning acoustic microscope inspection systems to find voids and other defects. Eleven samples for each type of underfill material have been subjected to the...

• Type: Journal
• Year: 2002
• Where: MR
• Authors: Hua Lu 0003, K. C. Hung, Stoyan Stoyanov, Chris Bailey, Y. C. Chan
• Keywords: Flip Chips, MR 2002, No-flow Underfill, No-flow Underfill Materials, Robotics