Sulfur hexafluoride (SF6) is a gaseous pollutant generated in manufacturing processes in the semiconductor industry. Hydrogen sulfide (H2S), as a reductant, was used to treat SF6 in a radio frequency (RF) plasma system. In the SF6/Ar plasma system, SiF4 and SO2 were the two dominant species detected in the glass reactor; other detected species were SO2F2, SOF2, and SOF4. In the SF6/H2S/Ar plasma system, HF and elemental sulfur were the main produced species. Although the species SiF4, SO2, SO2F2, SOF2, and SOF4 were detected in the SF6/H2S/Ar plasma system, adding H2S clearly inhibited the generation of these byproducts of SiO2 etching. At an input power of 5 W and an H2S/SF6 ratio of 2.9, the mass fraction of fluorine from feed SF6 converted into HF was 95.3%, while the mass fraction of sulfur from feed SF6 and H2S converted into elemental sulfur was 96.1%. Given the advantages of recovering HF and reclaiming elemental sulfur, hydrogen sulfide can be used as an auxiliary gas in treating SF6 in an RF plasma system.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering