摘要 |
Using a dry film resist that is a photosensitive resin, a resin mask layer is formed around electrodes on a substrate. A solder precipitating composition is applied on the substrate, and this solder precipitating composition is heated to precipitate solder on the surface of the electrodes. Subsequently, in removing the resin mask layer, at least one selected from glycol ethers and aminoalcohols is used. Thereby, the resin mask layer is removed after heating process. This makes it possible to easily remove the heat-processed resin mask layer in a short period of time without damaging solder resist and solder bumps on the substrate. |