Best Product Innovation:
New conductive adhesives with reduced silver content
(Daniel Hanselmann and team, Heraeus Materials Technology)
Conductive adhesives containing silver connect electronic and electrical components in electrical circuits, semiconductor components, smart cards, displays, and sensors. Conventional adhesives require a silver content of more than 70 percent by weight to maintain their electrical conductivity. If an adhesive contains too few silver particles, they can no longer touch each other, and the electrical connection is interrupted. Conductive adhesives play a critical role in electronics, but because of cost pressure, the number of competing technologies is steadily growing. Daniel Hanselmann and his team have developed a cost-effective alternative. Their innovation replaces the conventional spherical silver particles in the adhesive with lamellar conductive silver particles. These silver flakes are supported and aligned by a scaffolding of less expensive spherical filling materials. With this geometrical 'trick,' – the mixture of conductive and nonconductive particles – Heraeus is able to reduce the adhesive's silver content to less than 40 percent by weight without impairing its reliability and electrical properties.