Contact Resistance Comparison of Flip-Chip Joints Produced with Anisotropic Conductive Adhesive and Nonconductive Adhesive for Smart Textile Applications

Abstract

For applications in smart textiles, flip-chip bonding was applied with either an anisotropic conductive adhesive (ACA) or a nonconductive adhesive (NCA) to a heat-resistant fabric and a Si substrate as a reference. The average contact resistances of the flip-chip joints produced with each adhesive on each substrate were evaluated with varying the Cu and Sn thicknesses inversely over the range of 0-15 mu m to maintain a total thickness of 15 mu m of the Cu/Sn bump. The contact resistances of the flip-chip joints produced with ACA on Si, NCA on Si, ACA on fabric, and NCA on fabric were 6.5-12.2 m Omega, 15.6-26.5 m Omega, 5.3-10.2 m Omega, and 5.5-10.1 m Omega, respectively.