OPTICAL AND STRUCTURAL PROPERTIES OF Ta2O5 THIN FILMS DEPOSITED BY ION-BEAM-ASSISTED REATIVE DC MAGNETRON SPUTTERING

초록

Ta2O5 thin films were deposited by a reactive DC magnetron sputtering with an ion-beam-assistance at long substrate-to-target distance.In a convention reactive DC magnetron sputtering, an O2 gas admitted into the sputtering chamber to grow an oxide film may react with a metal target surface and form an snsulating oxide layer,resulting in arcing on the target surface and poisoning of it. In the present work, we installed an end-Hall ion source for the O2 and/or Ar ion beams to bombard Ta2O5 thin films growing on glass and Si substrats in the DC magneton sputtering and increased the substrate-to-target distance in order to reduce the target distance in order to reduce the target oxidation and increse the deposition rate of the oxide film. A reactive O2 gas was introduced into an ion soruce and near a substrate while an Ar gas was flown above the sputtering target such that the target was not exposed directly to the O2 gas.We studied the optical and structural properties of Ta2O5 thin films by use of in-situ ellipsometer,spectrophotometer, XRD, and AFM.An invstigation on the effects of ion beam parameters and sputtering conditions on Ta2O5 thin films will be reported.Finally,these results will be compared with those of TiO2 thin films,which were prepared by the same deposition method, for high refractibe index films in the optical multilayer coatings.