To provide a storage which can be excellent in shock resistance and temperature cycle resistance, and whose reliability can be improved.

The storage (SSD100) includes a semiconductor package 40 and a mounting substrate 30. The semiconductor package 40 includes a semiconductor chip 5 on which a nonvolatile semiconductor is formed, a resin sealing body 10 which seals the semiconductor chip 5, and lattice electrodes (a group electrode, solder balls 20) which are arranged in lattice shape on the rear surface of the resin sealing body 10. The mounting substrate 30 includes a bonding conductor 31 bonded to the solder ball 20, and has the semiconductor package 40 mounted thereon. The solder ball 20 includes a signal electrode 20A which is formed in the central region of the arrangement, and a dummy electrode 20B which is formed outside the signal electrode 20A.