13-12-2001 дата публикации
Номер: US20010051421A1
An electrode pad, a surface protection film, an inter-layer insulation film, an undercoat metal layer, and a rewiring layer are formed in that order on top of an insulation film formed on a wafer. A liquid photosensitive resin film and a solid photosensitive resin film, having negative photosensitive property, respectively, are sequentially formed across the entire surface of the wafer. The liquid photosensitive resin film is made of a resin having weaker adhesion with the undercoat metal layer than that of a resin for the solid photosensitive resin film. The liquid photosensitive resin film and the solid photosensitive resin film are subjected to exposure and development, thereby forming an opening for forming a bump electrode therein, and the bump electrode is formed inside the opening for forming the bump electrode. Practically at the same time when the liquid photosensitive resin film is removed by use of a removing solvent, the solid photosensitive resin film is peeled off and removed. Then, as no portion of the liquid photosensitive resin film and the solid photosensitive resin film is left out, unwanted portions of the undercoat metal layer can be removed with certainty.
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