Adhesive features of bonded interfaces subjected to temperature shock

Abstract

Defects on interfaces can gradually degrade the interfacial adhesion of IC package layers. This can be attributed to an unmatched coefficient of thermal expansion in the materials subjected to the temperature change. This study employed a fuzzy controller to stabilize both delamination force and energy absorption in order to represent adhesion strength. The three controllable factors were: dwell time, solder mask thickness and shock temperature; and the two uncontrollable factors were: delamination force and energy absorption.

Temperature shock was used to simulate environmental temperature destruction, and delamination force was employed to simulate a shear test. Dropped destruction (energy absorption) was reproduced in an impact test. An analysis of variance (ANOVA) was conducted to determine significant factors, the optimal quality, and the most damaging conditions. Finally, the delamination force and energy absorption were combined using fuzzy logic in order to analyze the multiple performance characteristics index (MPCI). The MPCI is the only index of specimen quality levels that can determine the effects of temperature on the interfacial adhesion strength of a substrate/solder mask under certain conditions.

Key words:

• IC packages
• temperature shock
• adhesion strength

Notes

Corresponding author. (Tel: [phone]; Fax: [phone]; Email: [email protected])