Dry etching of CuCrO2 thin films

Highly conducting films of p-type CuCrO2 are attractive as hole-injectors in oxide-based light emitters. In this paper, we report on the development of dry etch patterning of CuCrO2 thin films. The only plasma chemistry that provided some chemical enhancement was Cl2/Ar under inductively coupled plasma conditions. Etch rates of ∼500 Å min−1 were obtained at chuck voltages around −300 V and moderate source powers. In all cases, the etched surface morphologies were improved relative to un-etched control samples due to the smoothing effect of the physical component of the etching. The threshold ion energy for the onset of etching was determined to be 34 eV. Very low concentrations (≤1 at.%) of residual chlorine were detected on the etched surfaces but could be removed by simple water rinsing.