US Patent 11043489 Semiconductor device and manufacturing method thereof

A semiconductor device includes a first channel region disposed over a substrate, and a first gate structure disposed over the first channel region. The first gate structure includes a gate dielectric layer disposed over the channel region, a lower conductive gate layer disposed over the gate dielectric layer, a ferroelectric material layer disposed over the lower conductive gate layer, and an upper conductive gate layer disposed over the ferroelectric material layer. The ferroelectric material layer is in direct contact with the gate dielectric layer and the lower gate conductive layer, and has a U-shape cross section.