A COMMERCIAL GAS ANALYZER ADAPTED FOR THERMAL-DESORPTION STUDIES

A system for thermal desorption studies can be implemented very straig htforwardly from a commercial instrument designed for gas analyses. Th e commercial instrument incorporates a quadrupole mass spectrometer an d the vacuum station to operate the spectrometer. The instrument is mo dified with a stainless steel six-way cross device which accommodates a sample manipulator, a leak valve and an Ar sputtering gun. The sampl e foil is resistively heated with very linear rates using a custom mad e power supply. Descriptions of the custom made sample manipulator and power supply are given. Results of hydrogen and carbon monoxide desor ption from palladium foil are discussed.