High temperature Langmuir vaporization mass spectrometer

A high temperature Langmuir vaporization mass spectrometer (HTMS) for the analysis of solid and molten materials from room temperature up to 1700 °C was designed, built, and tested. Volatilizing species are analyzed by electron impact (EI) and by surface ionization (SI) modes. Non-volatile surface species are analyzed by the static secondary ion mass spectrometry (SIMS) mode. In addition, it is equipped with an Ar + dynamic SIMS gun for an elemental analysis mode and for sample cleaning. The ion source has a unified design so a single sample can be analyzed by EI, SI or SIMS modes in rapid sequence at constant or variable temperatures. The instrument and data system were designed with particular emphasis placed on the ability of the instrument to perform EI ionization of neutral species prior to condensation and reactive species prior to reaction, and on giving the user the ability to correlate data from different ionization modes with changing sample chemistry. The HTMS has been successfully applied to the analysis of ion-emitting molten glasses. Large samples mounted in small rhenium tubes have been studied at temperatures up to 1150 °C, while smaller samples on flat rhenium filaments have been analyzed at temperatures as high as 1700 °C.