A study of the surface reaction on the etched ITO thin films by using inductively coupled plasma

In this study, we investigated the etching characteristics of indium tin oxide (ITO) thin films at CF4/Ar plasma. The maximum etch rate of 29.8 nm/min for the ITO thin films was obtained at CF4/Ar (=80/20) gas mixing ratio. The standard conditions were the RF power of 800 W, the DC-bias voltage of −150 V, the process pressure of 2 Pa, and the substrate temperature of 40 °C. Corresponding to these etching conditions, chemical reaction of the etched ITO surface has been studied by X-ray photoelectron spectroscopy measurement to investigate the chemical reactions between the surfaces of ITO thin film and etch species. The preferential losses on the etched surfaces were investigated using atomic force microscopy.

► We investigated the etching characteristics of ITO thin films in a CF4/Ar (=80:20%) plasma.
► The chemical reaction and byproduct of the etching process were determined by XPS analysis.
► The surface morphology was explained by AFM.