CHARACTERISTICS OF INDIUM-TIN OXIDE THIN-FILM ETCHED BY REACTIVE ION ETCHING

Indium-tin oxide (ITO) films coated on glass have been etched by react ive ion etching (RIE) with a gas mixture of Ar and Cl-2. The etching r ates of ITO films depend strongly on power density, gas pressure, the composition of reactive gases, and the total flow rate of etchants. Ac cording to the results from the study, we can postulate that the ITO f ilms' etching follows the ion-assisted chemical etching. A high etchin g rate above 100 Angstrom/min can be achieved, and an etching mechanis m will be proposed. The selectivity of ITO films to glass reaches 35 w ith a 30 line/mm pattern. After exposure of ITO films to an Ar/Cl-2 mi xed gas plasma discharge, their sheet resistance does not markedly cha nge. The residue of Cl atoms exists only in the region near the surfac e. By means of parameter control, we can obtain good pattern images of ITO films measured by scanning electron microscopy (SEM).