A redistribution layer for an integrated circuit is made by forming a conductive interconnection layer; forming a conductive body in electrical contract with the interconnection layer; and covering the conductive body with a first coating layer having a thickness less than 100 nm. The first coating layer is configured to provide a protection against oxidation and/or corrosion of the conductive body. To carry out an electrical test of the integrated circuit, a testing probe locally perforates the first coating layer until the conductive body is electrically contacted by the testing probe.