US Patent 11789296 Optical modulator and package

An optical modulator includes a dielectric layer and a waveguide. The waveguide is disposed on the dielectric layer. The waveguide includes an electrical coupling portion, a slab portion, and an optical coupling portion. The slab portion is directly in contact with both of the electrical coupling portion and the optical coupling portion. The slab portion has a first sub-portion and a second sub-portion connected to the first sub-portion. A top surface of the electrical coupling portion, a top surface of the first sub-portion, and a top surface of the second sub-portion are located at different level heights.