Pad design for thermal fatigue resistance and interconnect joint reliability

Abstract

Embodiments described herein provide techniques for forming an interconnect structure that includes micro features formed therein. Such embodiments can assist with improving interconnect joint reliability when compared to conventional pads that have a flat surface. An interconnect structure may comprise: a metal pad over a substrate (e.g., a semiconductor package, a PCB, an interposer, etc.). Micro features may be formed in an edge of the metal pad or away from the edge of the metal pad. The micro features can assist with: (i) increasing the contact area between solder used to form an interconnect joint and the metal pad; and (ii) improving adherence of solder used to form an interconnect joint to the metal pad. These benefits can improve interconnect joint reliability by, among others, improving the interconnect joint's ability to absorb stress from substrates having differing coefficients of thermal expansion.