A general weibull model for reliability analysis under different failure criteria -application on anisotropic conductive adhesive joining technology

A new hybrid soldering and conductive adhesive joining technology using a fusible lowmelting- point alloy (LMPA) have been developed. A numerical method for numerical analysis of fusible particles behavior is proposed to investigate coalescence characteristics of fusible particles in solderable isotropic conductive adhesives (ICAs). For finding out suitable conditions to obtain reliable conduction paths, the present study examines the influence of process-related parameters such as volume fraction and viscosity on coalescence characteristics of fusible particles.

Download Full-text

Electrical and mechanical characterization of an anisotropic conductive adhesive with a low melting point solder

Microelectronic Engineering ◽

10.1016/j.mee.2008.05.038 ◽

2008 ◽

Vol 85 (11) ◽

pp. 2202-2206 ◽

Cited By ~ 23

Author(s):

Yong-Sung Eom ◽

Keonsoo Jang ◽

Jong-Tae Moon ◽

Jae-Do Nam ◽

Jong-Min Kim

Keyword(s):

Melting Point ◽

Mechanical Characterization ◽

Conductive Adhesive ◽

Anisotropic Conductive Adhesive

Download Full-text

Issues in Assembly Process of Fine Pitch Chip-on-Flex Packages for LCD Applications

Electronic and Photonic Packaging, Electrical Systems Design and Photonics, and Nanotechnology ◽

10.1115/imece2004-59155 ◽

2004 ◽

Cited By ~ 2

Author(s):

Changsoo Jang ◽

Seongyoung Han ◽

Jay Ryu ◽

Hangyu Kim

Keyword(s):

Bonding Process ◽

Conductive Adhesive ◽

Assembly Process ◽

Anisotropic Conductive Adhesive ◽

Advantages And Disadvantages ◽

Fine Pitch ◽

Laser Bonding ◽

Material Process ◽

Process Combination ◽

Underfill Material

Some of the current assembly issues of fine pitch chip-on-flex (COF) packages for LCD applications are reviewed. Traditional underfill material, anisotropic conductive adhesive (ACA) and non-conductive adhesive (NCA) are considered in conjunction with two applicable bonding methods including thermal and laser bonding. Advantages and disadvantages of each material/process combination are identified. Their applicability is further investigated to identify a process most suitable to the fine pitch packages (less than 40 μm). Numerical results and subsequent testing results indicate that NCA/laser bonding process produces most reliable joint for the fine pitch packages.

Download Full-text

A Novel Anisotropic Conductive Adhesive for Lead-Free Surface Mount Electronics Packaging

Electronic and Photonic Packaging, Electrical Systems Design and Photonics, and Nanotechnology ◽

10.1115/imece2005-83021 ◽

2005 ◽

Cited By ~ 3

Author(s):

S. Manian Ramkumar ◽

Krishnaswami Srihari

Keyword(s):

Surface Area ◽

Electronics Packaging ◽

Conductive Adhesive ◽

Lead Free ◽

The Novel ◽

Small Surface ◽

Surface Mount ◽

Anisotropic Conductive Adhesive ◽

Fine Pitch ◽

Very High

The electronics industry, in recent years, has been focusing primarily on product miniaturization and lead-free assembly. The need for product miniaturization is due to the continuous demand for portable electronic products that are multifunctional, yet smaller, faster, cheaper, and lighter. This is forcing the industry to design and assemble products with miniature passive and active devices. These devices typically have fine pitch footprints that provide a very small surface area for attachment. The solder attach technique relies primarily on the formation of intermetallics between the mating metallic surfaces. With a reduction in the surface area of the pads, the ratio of intermetallic to solder is very high once the solder joint is formed. This could result in unreliable solder joints, due to the brittle nature of intermetallics. In addition, the need to eliminate lead-based materials as a means of interconnection has renewed the industry’s interest in exploring other means of assembling surface mount devices reliably. This paper discusses the performance characteristics and preliminary research findings pertaining to a novel Anisotropic Conductive Adhesive (ACA) for electronics packaging applications, utilizing the Z Bond™ technology from Nexaura Systems, LLC. Typically, ACAs require the application of pressure during the curing process, to establish the electrical connection. The novel ACA uses a magnetic field to align the particles in the Z-axis direction and eliminates the need for pressure during curing. The formation of conductive columns within the polymer matrix provides a very high insulation resistance between adjacent conductors. The novel ACA also enables mass curing of the adhesive, eliminating the need for sequential assembly. The novel ACA’s I-V characteristics and performance under thermal and temperature-humidity aging are discussed in detail.

Download Full-text