Etching Characteristics of In2O3 and SnO2 Thin Films in an Inductively Coupled HBr/Ar Plasma: Effects of Gas Mixing Ratio and Bias Power

Abstract

An investigation of the etching characteristics and mechanisms of both In2O3 and SnO2 in a HBr/Ar inductively coupled plasma was carried out. The etching rates were measured in the range of 0-100% Ar and 100-300W bias power at a fixed gas flow rate (40 sccm), total gas pressure (6 mTorr), and input power (700 W). The plasma parameters and composition were determined using a combination of plasma diagnostics by a double Langmuir probe and a global (zero-dimensional) plasma model. It was found that both In2O3 and SnO2 etching rates are mainly controlled by the Br atom flux, with some sensitivity to the ion energy flux corresponding to the transitional regimes of the ion-assisted chemical reaction. (C) 2010 The Japan Society of Applied Physics