Die Attachment by Extremely Fast Pressure-Assisted Sintering of 200 nm Cu Particles

Abstract: To achieve a sinter bonding process of powder devices for the formation of a bondline with high-temperature mechanical sustainability and superior thermal conductance, the bonding between a Cu-finished die and substrate was performed at 300 °C in air by using a paste containing 200 nm Cu particles and a reducing solvent. For the sinter bonding at 5 MPa, a sufficient shear strength was attained even after an extraordinary short bonding time of 10 s (21.6 MPa). Moreover, the bonding at 2 MPa showed a shear strength of 21.8 MPa after a remarkably short bonding time (20 s), and a near-full density structure was revealed in the bondline after 60 s. The extremely fast sinter-bonding results were attributed to the small particle size and significantly enhanced reducibility of the solvent used. Graphic abstract: [Figure not available: see fulltext.]