Heater, reflow apparatus, and solder bump forming method and apparatus

Abstract

An apparatus characterized by a feature that in a stage on which a substrate or a jig holding a substrate is mounted, an opening closed when the substrate or the jig is mounted is provided and the substrate or the jig is heated by blowing hot air against the lower portion of the substrate or the jig and by a feature that a solder bump is formed on a pad electrode by heating or reflowing a solder composition which is a mixture containing solder particles, a flux component, and a liquid material which is liquid at normal temperature or changing to liquid when heated, and the composition is heated from the substrate side. With the former feature, oxidization of the solder paste on the substrate where no hot air comes and adhesion of particles to the substrate can be prevented, and with the latter feature, solder particles near the pad electrode are melted earlier and wet and spread over the pad electrode, solder particles above and far from the pad electrode are not melted sufficiently, and an effect of reducing the possibility that solder particles join together can be expected.