A semiconductor device includes a substrate, a gate structure on the substrate and a first conductive connection group on the gate structure. The gate structure includes a gate spacer and a gate electrode. The first conductive connection group includes a ferroelectric material layer. At least a part of the ferroelectric material layer is disposed above an upper surface of the gate spacer. And the ferroelectric material layer forms a ferroelectric capacitor having a negative capacitance in the first conductive connection group.