Title: Analysis of Relationship between Inorganic Gases and Fine Particles in Cleanroom Environment
Authors: Lin, I-Kai
Bai, Hsunling
Wu, Bi-Jun
Institute of Environmental Engineering
Keywords: Diffusion denuder system (DDS);AMCs (Airborne Molecular Contaminants);Micro-contamination;Cleanroom;Semiconductor device
Issue Date: 1-Jun-2010
Abstract: The concentrations and characteristics of major components in inorganic gases and fine particles were measured at the photo and etch cleanroom areas in a Taiwan semiconductor factory. The results showed that the major inorganic gases, as expressed in terms of volume concentration, were NH(3) and HF at 7-10 and 4-6 ppbv, respectively. The average PM(2.5) mass concentration were 17.52 and 18.23 mu g/m(3) at the photo and etch areas, respectively, with species of Na(+), NH(4)(+), Cl(-) and SO(4)(2-) had the highest concentrations in the PM(2.5) mass. And the inorganic species account for 56% and 62% of the particulate mass, respectively, at the photo and etch areas. Relatively stronger correlations were observed between NH(4)(+) and SO(4)(2-) with the correlation coefficient R(2) of 0.62 and 0.82, respectively, at the photo and etch areas; this indicates their common source was possibly from the gas to particle formation process. And NH(3) was found to co-exist with HF at the etch area due to their common source as process chemicals (NH(4)OH and HF) in the wet bench. In the predominant NH(3)-rich environment, ammonia is the basic neutralizing agent to form the ammonium aerosol in a cleanroom.
URI: http://dx.doi.org/10.4209/aaqr.2009.10.0065
ISSN: 1680-8584
DOI: 10.4209/aaqr.2009.10.0065
Volume: 10
Issue: 3
Begin Page: 245
End Page: 254
Appears in Collections:Articles