A semiconductor device includes a substrate having an insulating film on its surface, and ac active layer made of a semiconductive thin film on the substrate surface. A database such as the Web is searched for occurrences of tuples of information. The foam spacer has a plan-view area A2. The layer of pillar metal is reduced in diameter, the barrier layer is selectively removed from the surface of the layer of passivation after which reflowing of the solder metal completes the solder bump of the invention.