DETERMINATION IN-SITU OF CHEMICAL SOLVENT VAPORS IN A SEMICONDUCTOR WORKPLACE WITH AN OPEN-PATH FTIR SPECTROMETER

An FTIR spectrometer having a long absorbing path in an open field mod e is applied to measure the air quality of semiconductor facilities, e specially for chemical solvent vapors. This spectrometer is demonstrat ed to be a proper instrument to monitor chemical solvents widely used in the manufacture of integrated circuits. By means of the great sensi tivity accruing from the kilometer pathlength, we discovered that many residual chemical solvent vapors are released in these workplaces; th e limit of detection can attain the level of parts per billion by volu me. Recognized spectra of chemical solvents, such as 2-ethoxyethyl ace tate, 2-propanol, hexamethyl disilazane, aromatic hydrocarbons, alkyl derivatives of phenol, alkyl benzene sulfonate and dimethyl sulfoxide, are calibrated qualitatively and quantitatively. The related integrat ed absorption coefficients (or band intensities) are listed in this pa per. By examining the measured spectra, we found two chemical solvents (2-propanol and hexamethyl disilazane) in the workplace, at concentra tions about 20-500 ppbv in such environments.