Abstract: Provided are a reverse-reflow core, a semiconductor package, and a method of fabricating a semiconductor package. The semiconductor package includes: a semiconductor apparatus including a bump pad; and a bump portion bonded to the bump pad. The bump portion includes: a core; an intermetallic compound layer formed on the core; and a solder layer coating the intermetallic compound layer, wherein the thickness of a portion of the solder layer decreases as the distance between the portion of the solder layer and the bump pad increases. The reverse-reflow core, the semiconductor package, and the method of fabricating a semiconductor package enable the fabrication of a semiconductor package having high bonding strength and a high degree of precision.

Abstract: A solder ball for fluxless bonding includes a solder core, a first metal layer on a surface of the solder core, and a second metal layer on the first metal layer. The first metal layer includes at least one of nickel (Ni), silver (Ag), zinc (Zn), tin (Sn), chrome (Cr), antimony (Sb), platinum (Pt), palladium (Pd), aluminum (Al), or an alloy thereof. The second metal layer includes gold (Au). As the above solder ball for fluxless bonding is in use, a solder bump having high reliability may be formed via a relatively short, low cost, and simple process.