Wetting and interfacial behavior of Cu–Al/SiC systems: Influences of Si ion implantation and Al concentration

Abstract

Three doses (5 × 1015, 1 × 1016 and 5 × 1016 ions/cm2) of Si ions implantation into Si-terminated 6H–SiC substrate were carried out at an energy of 20 keV at room temperature. The wetting of pristine and Si-implanted 6H–SiC (Si–SiC) substrates by molten pure Cu, Cu-(42.9, 48.7, 70.4)Al alloys and pure Al were performed by the sessile drop technique under vacuum of ∼4 × 10−4 Pa at 1373 K. The surface characteristics of SiC substrates and wetting and interfacial behavior of Cu–Al/(Si-)SiC systems were analyzed and discussed. The equilibrium or final contact angles (θ) of Cu–Al/Si–SiC systems were increased more or less with the increase of Si ion implantation dose, and the Si ion implantation can markedly enhance the wettability of Cu-(0, 42.9)Al/SiC systems but weaken that of Cu-(48.7, 70.4, 100)Al/SiC systems. Interestingly, the graphitization phenomenon disappeared at the drop/substrate interface when the Al concentration was over 42.9%, and the Cu-42.9Al alloy cannot wet both the pristine 6H–SiC and Si–SiC substrates. These phenomena further demonstrated that the wetting of metal/SiC systems can be mainly determined by the metal-substrate interactions derived from the metal composition under a vacuum of and surface characteristics of metal drop and ceramic substrate during wetting.