projected range that depth is only an average of the depth of all the ions implanted above and below the target depth precise characteristics of the ion implantation that make it a significant ion implantation for purposes of this invention can vary because precise characteristics of the films can vary for example which ions should be used how deep the ion implantation should be what dosage should be used etc will vary with the composition and thickness of the film and perhaps even with the severity of the heating during annealing ordinarily one would want to use an ion for the damaging implant that is metallurgically compatible with the film and its underlying surface for example if the film is deposited on glass or silicon dioxide and the film is of silicon or silicon nitride silicon ions would be metallurgically compatible with such a system on the other hand it may be desirable to use argon a halogen or nitrogen as the ion species for the implantation there is some thought that the implantation should be at an energy that will provide maximum implantation damage at the interface between the film and its underlying surface by maximum damage i mean the maximum damage to lattice structures i e atomic displacement or interfacial atom mixing such damage is typified by vacancies being produced in a crystal lattice or atoms being moved into interstitial positions.