US Patent 10515954 Semiconductor device having fin structures of varying dimensions

A semiconductor device includes at least one first fin, a first gate, a first gate dielectric layer, at least one second fin, a second gate electrode, and a second gate dielectric layer. The first fin has a first width. The first gate electrode crosses the first fin. The first gate dielectric layer is between the first fin and the first gate electrode and has a first thickness. The second fin has a second width greater than the first width. The second gate electrode crosses the second fin. The second gate dielectric layer is between the second fin and the second gate electrode and has a second thickness less than the first thickness.