A semiconductor device having a semiconductor substrate, at least one of a
protruding electrode and wiring formed on one surface of the
semiconductor substrate, and a first resin film formed on this surface.
The first resin film has elasticity low enough to reduce stress induced
by a difference in thermal expansion coefficient between the
semiconductor substrate and the first resin film. A second resin film,
having higher elasticity or higher strength than the first resin film,
may be formed on the other surface of the semiconductor substrate.