An integrated circuit including an insulating layer having first and second opposite surfaces. The circuit includes, in a first area, first conductive portions of a first conductive material, located in the insulating layer, flush with the first surface and continued by first vias of the first conductive material, of smaller cross-section and connecting the first conductive portions to the second surface. The circuit further includes, in a second area, second conductive portions of a second material different from the first conductive material and arranged on the first surface and second vias of the first conductive material, in contact with the second conductive portions and extending from the first surface to the second surface.