The inverse problem of quantitative emission electron microscopy with account of distribution of the electron energy

Abstract

In emission electron microscope (EEM) energy distribution of emitted electrons can significantly affect the image contrast of microfields. This influence is the more the less energy of emitted electrons in volts differs from the residual of potentials of effective microfields. As usual it is accomplished in threshold photoelectron emission. Analytically this objective was solved for cases of contrast formation in EEM with using aperture or without that one. Determined from the obtained formulas and measurements built‐in potential between Ag particles (thickness 30 nm, lateral size 20×20 µm 2 ) and Si(100) substrate is 0.7 eV. Calculation shows that this value is two times higher without accounting of photoelectrons energy distribution (high pressure mercury lamp was used for excitation). Remarkable that the expression for correction that appeared in energy distribution of electrons emitted from the sample coincides with contrast defocus formula. It means that some initial energy of emitted electrons is equivalent to image defocus and thus can be compensated by some refocusing of images.