Adhesion strength and contact resistance of flip chip on flex packages––effect of curing degree of anisotropic conductive film

Fabrication of Core-Shell Structure of Ni/Au Layer on PMMA Micro-Ball for Flexible Electronics

“…9(b), I-V characteristic curve showed that current was linearly proportional applied voltage. The resistance is about 6.0 Ω compatible to the fine pitch interconnection 20) . It is assumed that the linearity is owing to the stability of the conductive layer.…”

Study of Structure and Failure Mechanisms in ACA Interconnections Using SEM

“…Moreover, the process is fluxless and no cleaning is required (Zhong, 2005). Furthermore, the process temperature is lower than that needed in soldering (Yim & Paik, 1998), which enables the use of heat sensitive or non-solderable substrate materials (Uddin et al, 2004). As the polymer matrix protects the contacts from mechanical damage and no underfilling is required (Lai & Liu, 1996), the ACA process costs less due to fewer processing steps (Yim & Paik, 2001).…”

“…For thermoset adhesives the bonding temperature together with the bonding time determine the degree of cure of the adhesive matrix. The higher the bonding temperature used the higher the degree of cure of the adhesive matrix is within the same amount of time (Chan & Luk, 2002a;Rizvi et al, 2005;Tan et al, 2004;Wu et al, 1997) as the higher temperature accelerates the crosslinking reaction (Uddin et al, 2004). Similarly, longer bonding time increases the degree of cure.…”

“…It has been suggested that during thermal testing above the T g of the ACA matrix sliding between the pad and the bump occurs Uddin et al, 2004). This may break the conductive particles and lead to failure.…”

ACF Curing Process Optimization for Chip-on-Glass (COG) Considering Mechanical and Electrical Properties of Joints

“…During the curing process, voids are generated between the chip, adhesion and glass panel. These voids may affect the adhesion strength of the ACF, resulting in low reliability (Uddin, et al, 2004). Mechanisms to affect the stability of contact resistance include water absorption, electrochemical corrosion and metal oxidation, resulting in ever-increasingly unstable resistance through time, particularly under high temperature and high humidity conditions (Wu & Chau, 2002).…”