Field-evaporation on the (001) plane was studied using atom-probe field ion microscopy in the presence of hydrogen at cryogenic temperatures. The results obtained from mass spectra and layer-by-layer analyses suggested that (1) the boron surface atoms reacted with the hydrogen gas atoms preferentially on the surface and many boron atoms field-evaporated as boron hydride ions with a holding voltage applied to the specimen, (2) a large part of the lanthanum surface atoms also formed hydride ions induced by a pulse-voltage on the surface but they dissociated into La3+ ions and neutral H atoms immediately after their field-evaporation, and (3) the lanthanum surface atoms made a great contribution to a hydrogen gas ion image of the LaB6(001) plane.

An Atom-Probe Analysis of the LaB6(001) Plane. II. Effect of Hydrogen Gas Atmosphere. Murakami, K., Adachi, T., Kuroda, T., Nakamura, S.: Surface Science, 1986, 176[1-2], 327-35