Fourier Transform Infrared Spectroscopic Methods for Industrial Hygiene Air Monitoring - II: Semiconductor Process Gasses.
Strang-CR; Levine-SP; Herget-WF
Hazard Assessment and Control Technology in Semiconductor Manufacturing, Lewis Publishers, Inc., Chelsea, Michigan 1989:259-264
A Fourier Transform Infrared (FTIR) spectrometer system with a long path gas cell was designed and tested for use in monitoring semiconductor processing areas for concentrations of hazardous materials below threshold limit levels. Two of the major concerns in this approach were the choice of the proper wavelength region for quantitation of gas and vapor mixtures and the choice of appropriate spectral resolution for rapid and accurate monitoring of the selected target analytes. The system was built to determine the resolution that would provide the optimum balance between analysis time, data storage space, accuracy of quantitation, and the ability to differentiate compounds with overlapping spectra when analyzing parts per billion levels of metal hydrides and organic vapors in simulated workplaces. Data were collected using a Nicolet 20 SXB FTIR spectrometer equipped with a liquid nitrogen cooled InSb/HgCdTe(MCT) sandwich detector. Concentrations of the gases detected ranged from 0.01 to 1.0 parts per million. Optimum spectral regions for quantitation of the study gases were listed. The authors suggest that for measuring low concentrations of arsine (7784421), phosphine (7803512), and diborane (19287457), the use of single point quantitation methods may not be appropriate due to the fact that these compounds do not appear to follow the Beer Lambert law at concentrations below part per million levels.
Semiconductors; Electronics-industry; Toxic-gases; Gas-detectors; Phosphorus-compounds; Arsenic-compounds; Air-quality-monitoring; Analytical-methods; Safety-practices;
7784-42-1; 7803-51-2; 19287-45-7;
Hazard Assessment and Control Technology in Semiconductor Manufacturing, Lewis Publishers, Inc., Chelsea, Michigan