Thin Solid Films, Vol.518, No.1, 372-377, 2009
Etch characteristics of indium zinc oxide thin films in a C2F6/Ar plasma
Dry etching of indium zinc oxide (IZO) thin films was performed using inductively coupled plasma reactive ion etching in a C2F6/Ar gas. The etch characteristics of IZO films were investigated as a function of gas concentration, coil rf power, dc-bias voltage to substrate, and gas pressure. As the Us concentration was increased, the etch rate of the IZO films decreased and the degree of anisotropy in the etch profile also decreased. The etch profile was improved with increasing coil rf power and dc-bias voltage, and decreasing gas pressure. An X-ray photoelectron spectroscopy analysis confirmed the formation of InF3 and ZnF2 compounds on the etched surface due to the chemical reaction of IZO films with fluorine radicals. In addition, the film surfaces etched at different conditions were examined by atomic force microscopy. These results demonstrated that the etch mechanism of IZO thin films followed sputter etching with the assistance of chemical reaction. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Dry etching;Indium zinc oxide;C2F6/Ar;Transparent conducting oxide;Solar cell;Thin film transistor