Abstract
Field emission patterns and emission characteristics concerning single crystal tips of LaB6, CeB6, PrB6, NdB6 and SmB6 were studied. The (001) oriented cathode tips were prepared by means of the flux technique and the electrolytic etching method. MeB6 cathodes showed symmetrical field emission patterns either by flashing operation with some definite temperature range (for example, 1400-1500°C for a La, cathode), or by field desorption cleaning. These emitters displayed characteristic patterns easily correlated with the body-centered cubic crystal structure. Most crystals gave (001) built-up patterns by the heat treatment of 800°C× 30-40 min. with the anode voltage applied. Emission characteristics for a period of about an hour after the flashing treatment were mainly governed by adsorption, desorption and migration of residual gas molecules on the cathode surface.
