Wiring circuit substrate

摘要

The invention relates to a wiring circuit substrate, comprising: an insulating layer (306) having a face on which a first metal layer (307) is patterned; etched protrusions (308) projecting from said first metal layer in a state of passing through said insulating layer and formed of a conductor-forming metal; and a plurality of solder balls (315) or solder bumps (314) formed selectively on a surface of the first metal layer opposite from the etched protrusions, at least some of the solder balls or solder bumps being at least partly aligned with the etched protrusions.