Ion beam modification of transparent conducting indium-tin-oxide thin films

We have examined the effects of ion implantation of various chemical species on the electrical properties of transparent, conducting indium-tin-oxide (ITO) polycrystalline films with resistivities less than 200 mu Omega cm and optical transmission greater than 90%. We report on implantations of N+, O+, F+, Ne+ and In+ under a variety of conditions, At low to moderate doses, damage effects dominate and reduce the conductivity slightly before saturating at doses of similar to 10(14)/cm(2). At higher doses, when the implanted concentration becomes comparable to the free-carrier concentration (similar to 10(21)/cm(3)), some species (e.g., In+) can improve the conduction slightly, while other species (e.g., O+) can reduce the conduction, in some cases by several orders of magnitude, We also describe preliminary results of some new experiments begun with single-crystal ITO films to permit better characterization of the damage effects.