FORMATION PROCESS AND ELECTRICAL PROPERTY OF RUO2 THIN-FILMS PREPAREDBY REACTIVE SPUTTERING

RuO2 thin films were prepared by reactive sputtering in Ar + O-2 gas a nd their crystal structure, chemical binding state and resistivity wer e studied. We observed that the formation process of RuO2 films could be classified into two process as depending on the O-2 dow ratio. In t he 18-28% O-2 dow region, the deposition rate around 28 nm/min was obt ained and well crystallized RuO2 films with preferential (110) plane w ere deposited. In the O-2 flow region above 32%, the deposition rate d ecreased to around 8 nm/min and fine grain or amorphous RuO2 films wer e deposited. These changes of deposition rate and crystallinity were c aused by the difference of oxidation reaction process of Ru at the sub strate surface or the target surface. Resistivity of the RuO2 films de creased with an increase of the substrate temperature and a minimum re sistivity of 42 mu Omega cm was obtained at 500 degrees C and 20% O-2 flow.