Each connecting pad includes a continuous top metal layer on the top metallization level and having on its top face an area for welding a connecting wire. Also, the pad has a reinforcing structure under the welding area and includes at least one discontinuous metal layer on the immediately next lower metallization level, metal vias connecting the discontinuous metal layer to the bottom surface of the top metal layer, and an isolating cover covering the discontinuous metal layer and its discontinuities as well as the inter-via spaces between the two metallic layers.