A semiconductor device includes first level wires; a low-dielectric constant film on the first level wires; first flat vias embedded in the low-dielectric constant film connected to the first level wires, each via having a first length in a longitudinal direction of the first level wires and a second length in a orthogonal direction to the first direction on a plane where the first level wires are disposed, aspect ratio of at least one of the first and second lengths to a height perpendicular to the plane is over 1; and second level wires disposed on the low-dielectric constant film connected to the first vias.