Direct Analysis of Photoresist

A simple method for analyzing photoresists using inductively coupled plasma mass spectrometry is discussed. It is possible to freely aspirate a 10-fold diluted photoresist sample (30% resin) into an inductively coupled plasma mass spectrometer which has been specially designed to handle high matrix samples. The Agilent 7500s with ShieldTorch System features an advanced RF generator which produces a highly robust and high temperature “cool” plasma. The unique combination of the ShieldTorch and cool plasma conditions give effective interference removal of carbon and argon based interferences on 24Mg (12C2) and 52Cr(40Ar12C) and 39K(38Ar1H), 40Ca(40Ar) and 56Fe(40Ar16O), which would otherwise limit standard quadrupole inductively coupled plasma mass spectrometry operation for this application.