Fluorinated porous organic polymers for efficient recovery perfluorinated electronic specialty gas from exhaust gas of plasma etching

Abstract

Recovering of high value-added perfluorinated electronic specialty gases (F-gases) in plasma etching waste gas is a challenging task in the silicon-based semiconductor industry. In recent years, the adsorptive separation technology based on porous materials has been regarded as a effective strategy to capture and recover F-gases due to its energy-saving and high operational feasibility. Herein, two porous organic polymers (POPs) with fluorinated skeleton structure (termed POPTrA-4F and POPTrA-8F) were developed to selective capture and recycle of F-gases in plasma etching exhaust gas. Single-component gas adsorption and IAST calculation show that two fluorinated porous polymers can selectively capture F-gases from mixed gas. Theoretical simulations based on DFT reveal the selective adsorption mechanism of fluorinated polymers to F-gases at molecular level, and give the binding energy between polymers and gas molecules. Furthermore, time-dependent adsorption rate tests and dynamic breakthrough experiments confirm that two fluorinated polymers could preferentially adsorb F-gases and exhibit excellent cycling durability. These results demonstrate that fluorine-functionalized POPs have great potential to effectively capture and recover F-gases in plasma etching exhaust gas.