Electron beam effects during analysis of glass thin films with auger electron spectroscopy

Migration of sodium in thin films of soda‐silica glass deposited on a stainless steel substrate has been studied. The amounts of charge trapping and local heating were a strong function of beam parameters for thin films. For example, the time required for the sodium Auger signal to decay to 50% of its initial value increased as the beam energy was increased or as the current density was decreased. The rearrangement of sodium due to charge trapping was calculated and compared to experimental data. The calculated and experimental data agree well and indicate that fields of ∼10⁵ V cm⁻¹ exist during analysis. The depth distribution of sodium indicates that either electrons or ion bombardment can cause sodium migration during analysis. The cross‐section for electron‐induced desorption was measured to be 3 × 10⁻²⁰ cm² for sodium in this glass, therefore it is only important at very high current densities.