Low global warming potential gas for plasma processing application

Plasma processing requires a low dielectric strength gas to initiate quick discharge, allowing for plasma etching and other important processes. It should also produce an abundance of F and CF_x radicals through the various dissociation channels. The fluorine radicals are highly reactive and used for etching materials like Si, SiO₂, and Si₃N₂; thus, they are also important for surface reactions. The CF_x radicals assist in polymer formation or passivation in some processes. However, high global warming potential (GWP) gases are presently used, and efforts are required to minimise the emission of these greenhouse gases. Considering the negative environmental impact, we are looking for new gases that can replace high GWP gases in plasma processing applications. The new gas should have low GWP and low toxicity, with non-toxic by-products. Further, the dielectric strength should be low so that less power is required to ignite the plasma. We do a quantum chemistry calculation using GAUSSIAN09 software to study the dissociation pathways. To determine the dielectric strength of the gas, Boltzmann equation is solved using the BOLSIG+ software. The electron impact cross section is obtained using the R-matrix method via QUANTEMOL-EC software.