emission control
Emission control systems capture and neutralize hazardous emissions from process tools before discharge to atmosphere, ensuring environmental compliance and worker safety. Emission types: (1) Toxic gases—silane (SiH₄), arsine (AsH₃), phosphine (PH₃), boron trichloride (BCl₃); (2) Corrosive gases—HCl, HF, Cl₂, HBr; (3) Greenhouse gases—CF₄, C₂F₆, SF₆, NF₃, N₂O; (4) Flammable gases—H₂, SiH₄; (5) Particulate—process byproducts, CVD powder. Abatement technologies: (1) Thermal oxidation (burn/wet scrub)—combust hazardous gases, scrub products; (2) Plasma abatement—plasma decomposition of PFCs; (3) Catalytic—catalytic conversion at lower temperatures; (4) Wet scrubbing—dissolve water-soluble gases (HCl, HF, NH₃); (5) Dry scrubbing—chemical adsorption on solid media; (6) Point-of-use (POU) abatement—treat at tool exhaust before reaching house scrubber. PFC abatement: critical for reducing greenhouse gas emissions—destruction/removal efficiency (DRE) >90% required. Monitoring: continuous emission monitoring systems (CEMS), periodic stack testing, ambient air monitoring. Regulations: EPA Clean Air Act, local air quality permits, SEMI S22 guidelines. Abatement maintenance: media replacement (dry scrubbers), water treatment (wet scrubbers), burner maintenance (thermal). Cost: significant operating expense—gas, water, power, media, maintenance. Critical infrastructure for environmental compliance and sustainable fab operations.