A NOVEL LOW-COST, HIGH-PERFORMANCE THERMALLY AND ELECTRICALLY CONDUCTIVE ADHESIVEAuthors: Fritz Byle and Jin Liu
Date Published: 2/25/2005 Conference: Pan Pacific Symposium
Material and process strategies currently used include soldering via performs, wire, paste and pre-plated deposits, Ag-filled (silver-filled) conductive adhesives, and other strategies. While the soldered interconnections provide a good electrical and thermal path, they can fall short in reliability and cost. Ag-filled adhesives have a high initial cost associated with high concentrations of silver flake.
The subject of this paper is a novel concept in composite interconnection, providing the electrical and thermal performance of a soldered interconnection with enhanced reliability and low cost of a polymer-metal composite. The material does away with the uncontrolled appearance of large voids characteristic of traditional solder pastes, substituting a fine columnar structure that maintains thermal properties while enhancing reliability.
The process ease economics of a paste-based process are incorporated through SMT equipment and process compatibility. The material cost is significantly less than silver-filled isotropic conductive adhesives, and the thermal conductivity is significantly higher.
Substituting a unique alloy that can be made to shift its melting point after a post-reflow bake enables high-temperature endurance combined with a low initial processing temperature. The melting point of the fusible metal in the system is made to shift from 138°C to 205°C.
Members download articles for free:
Not a member yet?
What else do you get when you join SMTA? Read about all of the benefits that go along with membership.
Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.