Effect of compression pressure on strength of low-temperature sinter bonding produced using silver formate

Abstract

ABSTRACT Novel pressure-assisted sinter bonding at 200°C using silver (Ag) formate particles was performed in air using an Ag-finished die and substrate to achieve a reliable Ag bondline even at high temperatures. The Ag formate particles, prepared by immersing Ag2O particles for 3\u2005min in a formic acid solution, indicated a pyrolysis reaction near 130°C, forming pure Ag and gases (carbon dioxide and hydrogen). With a paste prepared by mixing the Ag formate particles with α-terpineol, the bonding under 10\u2005MPa exhibited an adequate shear strength of 270\u2005MPa after 3\u2005min. Moreover, a near-full-density structure was observed in the formed bondline after 10\u2005min. Consequently, the compression pressure of 10\u2005MPa resulted in significantly enhanced bondability with reduced void fraction in the formed Ag bondline.