Thermodynamic investigation of an insulator irradiated by a low-energy electron beam
Laboratoire de Physique des Solides, Université Paris-Sud, CNRS
UMR 8502, Bât. 510, 91405 Orsay Cedex, France
Corresponding author: a email@example.com
Published online: 9 December 2005
The surface of an insulating material irradiated by a beam of low energy electrons charges positively if the yield of secondary electron is greater than unity. For such a dynamical equilibrium, the thermodynamic properties have been investigated by measuring the surface potential in response to a temperature oscillation of the material. It is shown that an oscillation amplitude of 0.4 K at 530 K induces an oscillation of the surface potential of about 0.5 volts. The frequency dependence indicates a monotonous decrease in the response with decreasing frequency, extrapolating to zero at zero frequency. We propose that this modification of the surface charge is driven by the temperature dependence of a gas of charged particles in equilibrium with the vacuum level.
PACS: 73.20.-r – Electron states at surfaces and interfaces / 61.14.Hg – Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED) / 68.60.Dv – Thermal stability; thermal effects
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005