Abstract: A method for forming a copper conductor in an electronic structure by first depositing a copper composition in a receptacle formed in the electronic structure, and then adding impurities into the copper composition such that its electromigration resistance is improved is disclosed. In the method, the copper composition can be deposited by a variety of techniques such as electroplating, physical vapor deposition and chemical vapor deposition. The impurities which can be implanted include those of C, O, Cl, S and N at a suitable concentration range between about 0.01 ppm by weight and about 1000 ppm by weight. The impurities can be added by three different methods. In the first method, a copper seed layer is first deposited into a receptacle and an ion implantation process is carried out on the seed layer, which is followed by electroplating copper into the receptacle.