Semiconductor apparatus with improved thermal and mechanical characteristic under-fill layer and manufacturing method therefor

In a semiconductor apparatus comprising a semiconductor chip, a wiring substrate having the semiconductor chip mounted thereon, an under-fill resin sheet interposed between the semiconductor chip and the wiring substrate, and a resin sealing body for sealing the semiconductor chip, the under-fill resin sheet and the wiring substrate, the under-fill resin sheet is greater than the semiconductor chip in size, and its end is exposed from at least one side face of the resin sealing body. Since an end of the under-fill resin sheet is exposed from at least one side face of the resin sealing body, then the water contained in the under-fill resin sheet escapes from an exposed end of the under-fill resin sheet to the outside of the resin sealing body, thus making it possible to improve re-flow resistance of the semiconductor apparatus.