Effect of gas mixing ratio on etch behavior of ZrO2 thin films in Cl2-based inductively coupled plasmas

Abstract

Articles you may be interested inEffect of adding small amount of inductive fields to O2, Ar/O2 capacitively coupled plasmas J. Appl. Phys. 111, 093301 (2012); 10.1063/1.4705362 Etching characteristics and mechanisms of SiC thin films in inductively-coupled HBr-Ar, N2, O2 plasmas J. Vac. Sci. Technol. A 29, 06B103 (2011); 10.1116/1.3655561 Etch mechanism of In 2 O 3 and SnO 2 thin films in HBr-based inductively coupled plasmas J. Vac. Sci. Technol. A 28, 226 (2010); 10.1116/1.3294712 Effect of gas mixing ratio on etch behavior of Zr O 2 thin films in B Cl 3 ∕ He inductively coupled plasma J. Vac. Sci. Technol. A 26, 344 (2008); 10.1116/1.2891255 Plasma parameters analysis of various mixed gas inductively coupled plasmasThe analysis of the ZrO 2 thin film etch mechanism in the Cl 2 / Ar, Cl 2 / He, and Cl 2 / N 2 inductively coupled plasmas was carried out. It was found that an increase in additive gas fraction at fixed gas pressure and input power results in increasing ZrO 2 etch rate, which changes from 1.2 nm/ min for pure Cl 2 plasma up to 3.15, 2.40, and 2.31 nm/ min for 80% Ar, N 2 , and He, respectively. Langmuir probe diagnostics and zero-dimensional plasma modeling indicated that both plasma parameters and active species kinetics are noticeably influenced by the initial composition of the gas mixture. From the model-based analysis of etch kinetics, it was shown that, similarly to the case of BCl 3 -based plasmas, the behavior of the ZrO 2 etch rate corresponds to the ion-flux-limited etch regime.

A global (volume averaged) model of a Cl2/Ar discharge: I. Continuous power

“…Chlorine and its mixtures are widely used for thin film etching, in particular poly-silicon. The etching of various thin films has been demonstrated in Cl 2 /Ar chemistry, including SiO 2 and MgO [2], Ta and TaN [3], ZnO [4], ZrO 2 [5] and Bi 4−x La x Ti 3 O 12 [6]. Shin et al [3] suggest that Cl radical density plays an important role in determining the etch rate and that the radical density is considerably influenced by the Cl 2 /Ar mixing ratio.…”