Semiconductor device

A semiconductor device, in which a plurality of IC chips that perform the same cipher calculation in parallel are laminated or stacked, performs data processing including the cipher calculation. A chip that compares and verifies results of the cipher calculations performed by the plurality of chips is laminated in an intermediate layer whose element surface is covered by another chip. For example, when three chips are laminated, a chip in the intermediate layer sandwiched by the upper layer and the lower layer has a comparative verification function.