An alternative method for metallization by laser and ion beam irradiation

A scanning Ar⁺ laser beam and a focused 30 keV Ga⁺ ion beam (FIB) have been used to transform an insulating (or high-resistivity semiconducting) noble metal oxide film to a conducting layer. Resulting from these experiments we propose a method for the fast and one-step metallization by laser or ion beam irradiation using platinum oxide thin films, prepared by magnetron sputtering under an argon/oxygen plasma. A maskless patterning of the platinum oxide film is possible by scanned laser and focused ion beam irradiation. Additionally to the scanning methods it is also possible to pattern the PtO₂ film by broad ion beam irradiation using masks. For wiring we patterned conducting areas of up to 2 mm width and up to 15 mm length with a broad Ga⁺ ion beam (energy: 300 keV, dose: 5×10¹⁵ Ga⁺/cm²). The laser- and the ion-patterned large areas could be easily bonded with an Al wire to carry out four-point resistance measurements.