New Mass Spectrometer Ion Source for Solids

Abstract

An ion source with magnetron geometry for mass spectrometric analysis of low vapor pressure materials is constructed. Using the magnetron configuration of this source a new method for obtaining the ion beams of low vapor pressure elements is developed. The material to be analyzed is fixed to the hot cathode, so that the cathode can be used simultaneously as a hot support for charge material and as a source of electron emission. The vapor of the material is produced by the combined effect of filament heating of charge material and cathode sputtering by the ions of carrier gas. The method was successfully applied in obtaining ions of Cr, Fe, Ti, Ir, La, Ta, Nd₂O₃, Re, Ce₂O₃, and ZrO₂. The collector ion currents range up to 10⁻¹¹ A. The energy spread is measured by means of both the retarding potential and the beam deflection methods. It is found that there was no difference in the energy spread of this source and a classical Nier's ion source for mass spectrometry. The advantages of the source are also described.