Atmospheric pressure ionization mass spectroscopy for the study of permeation in polymeric tubing

Author

Ma, Ce ; Haider, Asad M. ; Shadman, Farhang

Author_Institution

Dept. of Chem. Eng., Arizona Univ., Tucson, AZ, USA

Volume

6

Issue

4

fYear

1993

fDate

11/1/1993 12:00:00 AM

Firstpage

361

Lastpage

366

Abstract

An atmospheric pressure ionization mass spectrometer (APIMS) is used to determine the permeation coefficients for two widely used kinds of polymeric tubing, PF and Kel-F (PCTFE), at 25°C and 75°C. In the experiments, an ultra-high-purity N₂ gas flow was maintained through the test tubing. The net impurity uptake by nitrogen due to the permeation of O₂, CO₂, H₂O, and CH₄ from surrounding air into the polymeric tubing was measured by APIMS with sub-ppb sensitivities. CH₄ had the highest and O₂ had the lowest permeation coefficients. Results show that Kel-F was a superior barrier material for all impurities studied. The permeation coefficients for these polymers increased with temperature but did not change significantly with the permeant partial pressure. The permeability of PFA showed a stronger temperature dependence than that of Kel-F

Keywords

VLSI; integrated circuit technology; mass spectroscopy; polymers; 25 degC; 75 degC; APIMS; Kel-F; PF; atmospheric pressure ionization mass spectrometer; barrier material; permeant partial pressure; permeation coefficients; polymeric tubing; ultra-high-purity N₂ gas flow; Fluid flow; Impurities; Ionization; Mass spectroscopy; Nitrogen; Permeability; Polymers; Temperature dependence; Temperature sensors; Testing;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.267647

Filename

267647