US Patent 10115684 Semiconductor device

A semiconductor device includes a first semiconductor chip including a first plurality of wiring layers, and a first coil, a first bonding pad, and first dummy wires formed in an uppermost layer of the first plurality of the wiring layers, and a second semiconductor chip including a second plurality of wiring layers, a second coil, a second bonding pad, and second dummy wires formed in an uppermost layer of the second plurality of the wiring layers. The first semiconductor chip and the second semiconductor chip face each other via an insulation sheet. The first coil and the second coil are magnetically coupled with each other.