US Patent 11437376 Compact 3D stacked-CFET architecture for complex logic cells

A 3D IC includes a substrate having a substrate surface, a first stack of semiconductor devices stacked along a thickness direction of the substrate, and a second stack of semiconductor devices stacked along the thickness direction of the substrate and provided adjacent to the first stack in a direction along the substrate surface. Each semiconductor device of the first and second stack includes a gate and a pair of source-drain regions provided on opposite sides of the respective gate, and each gate of the first and second stack is a split gate. A gate contact is physically connected to a first split gate of a first one of the semiconductor devices. The gate contact forms at least part of a local interconnect structure that electrically connects the first semiconductor device to a second semiconductor device in the 3D IC.