Nano‐ and micro‐filled conducting adhesives for z‐axis interconnections: new direction for high‐speed, high‐density, organic microelectronics packaging

Purpose – The purpose of this paper is to discuss the use of epoxy‐based conducting adhesives in z‐axis interconnections.Design/methodology/approach – A variety of conductive adhesives with particle sizes ranging from 80 nm to 15 μm were laminated into printed wiring board substrates. SEM and optical microscopy were used to investigate the micro‐structures, conducting mechanism and path. The mechanical strength of the various adhesives was characterized by 90° peel test and measurement of tensile strength. Reliability of the adhesives was ascertained by IR‐reflow, thermal cycling, pressure cooker test (PCT), and solder shock. Change in tensile strength of adhesives was within 10 percent after 1,000 cycles of deep thermal cycling (DTC) between −55 and 125°C.Findings – The volume resistivity of copper, silver and low‐melting point (LMP) alloy based paste were 5 × 10−4, 5 × 10−5 and 2 × 10−5 Ω cm, respectively. Volume resistivity decreased with increasing curing temperature. Adhesives exhibited peel strength...

[1]  Magnus Willander,et al.  Spatial distribution of metal fillers in isotropically conductive adhesives , 2001 .

[2]  Johan Liu,et al.  Conductive adhesives for electronics packaging , 1999 .

[3]  Hongyu Yu,et al.  The effect of annealing on the morphologies and conductivities of sub-micrometer sized nickel particles used for electrically conductive adhesive , 2006 .

[4]  Steven G. Rosser,et al.  Modeling and Simulation of 12 . 5 Gb / s on a HyperBGA ® Package , 2003 .

[5]  Jun Xiao,et al.  Thermal and Mechanical stability of electrically conductive adhesive joints , 2005 .

[6]  Ryan D McBride,et al.  Modeling and simulation of 12.5 Gb/s on a HyperBGA/sup /spl reg// package , 2003, IEEE/CPMT/SEMI 28th International Electronics Manufacturing Technology Symposium, 2003. IEMT 2003..

[7]  Ching-Ping Wong,et al.  Conductivity enhancement of nano silver-filled conductive adhesives by particle surface functionalization , 2005 .

[8]  Jianmin Qu,et al.  Interfacial Versus Cohesive Failure on Polymer-Metal Interfaces in Electronic Packaging—Effects of Interface Roughness , 2002 .

[9]  Lilei Ye,et al.  Effect of Ag particle size on electrical conductivity of isotropically conductive adhesives , 1999 .

[10]  Kozo Fujimoto,et al.  New Process of Self-organized Interconnection in Packaging by Conductive Adhesive with Low Melting Point Filler , 2003 .

[12]  Erol Sancaktar,et al.  Pressure-dependent conduction behavior of various particles for conductive adhesive applications , 1999 .

[13]  Yuewu Zeng,et al.  Development of a Novel Isotropic Conductive Adhesive Filled with Silver Nanowires , 2006 .

[14]  Yi Li,et al.  Monolayer-protected silver nano-particle-based anisotropic conductive adhesives: Enhancement of electrical and thermal properties , 2005 .

[15]  Masahiro Inoue,et al.  Effect of curing conditions on the electrical properties of isotropic conductive adhesives composed of an epoxy‐based binder , 2006 .

[16]  H. Nishikawa,et al.  Electrical Characteristics of a New Class of Conductive Adhesive , 2005 .

[17]  K. Chou,et al.  Effect of nano-sized silver particles on the resistivity of polymeric conductive adhesives , 2005 .

[18]  F. Coughlan,et al.  A study of electrically conductive adhesives as a manufacturing solder alternative , 2006 .

[19]  Kozo Fujimoto,et al.  Adhesive Joining Process and Joint Property With Low Melting Point Filler , 2005 .

[20]  J. Libous,et al.  Comparison of multilayer organic and ceramic package simultaneous switching noise measurements using a 0.16 /spl mu/m CMOS test chip , 2001, 2001 Proceedings. 51st Electronic Components and Technology Conference (Cat. No.01CH37220).