A Computational Method for Screening Low-GWP Fluorinated Gases in Semiconductor Manufacturing

Abstract

The widespread use of fluorinated gases in semiconductor manufacturing has raised significant environmental concerns due to their high global warming potential (GWP). To address this issue, we developed a systematic methodology for screening and evaluating low-GWP F-gases based on density functional theory (DFT) calculations. The infrared absorption cross-section (ACS) spectra and radiative efficiencies (RE) of candidate gases were predicted and systematically corrected using an empirical scaling factor derived from the correlation between calculated and experimentally measured RE values. This correction significantly improved the accuracy of GWP predictions. The methodology was successfully validated against representative F-gases, yielding GWP1oo estimates that closely align with reported values for high-GWP gases (GWP<inf>1oo</inf>=2,240), mid-GWP gases (GWP<inf>1oo</inf>=87), and low-GWP gases (below GWP1oo=10). Notably, several candidate gases, such as COF<inf>2</inf>, CF<inf>3</inf>OCFCF<inf>2</inf>, CF<inf>3</inf>C(O)CF(CF<inf>3</inf>)<inf>2</inf>, and C<inf>6</inf>F<inf>6</inf>, exhibited estimated GWP1oo values of 1.79, 2.69, 3.03, and 7.56, respectively, which are consistent with reported values. They were re-confirmed by the proposed method as promising low-GWP alternatives to conventional high-GWP etching and cleaning gases. By adopting a practical, accessible DFT methodology, this approach delivers reliable comparisons of GWP values among candidate gases and supports rapid, on-site GWP assessments without requiring specialized expertise. © 1988-2012 IEEE.