Type Description Target value for <100 nanometer process
Acids A corrosive gas that reacts chemically as an acid
(an electron acceptor)
0,01 PPB
Base A corrosive gas that reacts chemically as a base
(an electron donor)
0,75 PPB
Condensable A contaminant with a boiling point that is typically above room temperature and that can condense on a surface 0,07 PPB
Dopants A contaminant that modifies the electrical properties of a material 0,01 PPB
Type Typical fresh air contamination Typical urban concentrations up to Typical rural concentrations up to Typical indoor contamination
Acids SO₂, NOx 10 PPB 10 PPB HCl, HF and other mineral acids
Base NH₃ 5 PPB 10 PPB Ammonia, NMP and other amines
Condensable VOC, PAH 20 PPB 10 PPB Siloxanes, plasticizers, anti-oxidants and solvents
Dopants Boron
seaside environment
Arsenic, Phosphates, Boron
Media type Contaminants Typical application
AAA Polycyclic aromatic hydrocarbons (PAC), Ozone, NOx, SO2, VOC's - approx. 20 PPB Industrial high-tech applications, cleanrooms for micro-electronics, pharmaceutical, food, fresh air AHU and/or FFU installation
AMA Mineral acids Etching and optical processes
AMB Ammonia and amines Lithographic and optical processes
AXB Ammonia and amines Lithographic and optical processes extended capacity
AMS H2S, SO23, radioactive iodine waste water and waste processing, hospital radiological lab