Artifacts, Hydrogen Promotion, and Field-Ion Microscopy of Nonrefractory Metals

Abstract

Ideally the field-ion microscope specimen would be part of a sphere cut through the crystal lattice in a way that all atoms having their centers outside this sphere would be removed and all remaining surface atoms would be imaged. In reality the various physical effects connected with the surface preparation process, by field evaporation, and with the imaging process, by field ionization, cause deviations from the ideal situation. Many of them have been realized to exist since the early days of field-ion microscopy, but only recently has it been suggested to consider them as artifacts,¹ a term familiar to optical and electron microscopists. Sometimes these artifacts are hard to distinguish from intrinsic lattice imperfections, so that their study is of basic importance for the proper interpretation of field-ion micrographs.