US Patent 11791217 Gate structure and method with dielectric gates and gate-cut features

A structure includes a fin on a substrate; first and second gate stacks over the fin and including first and second gate dielectric layers and first and second gate electrodes respectively; and a dielectric gate over the fin and between the first and second gate stacks. The dielectric gate includes a dielectric material layer on a third gate dielectric layer. In a cross-sectional view cut along a direction parallel to a lengthwise direction of the fin and offset from the fin, the first gate dielectric layer forms a first U shape, the third gate dielectric layer forms a second U shape, a portion of the first gate electrode is disposed within the first U shape, a portion of the dielectric material layer is disposed within the second U shape, and a portion of an interlayer dielectric layer is disposed laterally between the first and the second U shapes.