Konopsky V.N., Sekatskii S.K., Letokhov V.S.
Single atom electron emission from the silicon tip coated by calcium fluoride with samarium dopant ions. // Journal de Physique IV, 1996, V.6-C5, P.125-128.

We present the first experimental results of the studying of field electron emission from sharp silicon tips covered by thin dielectric CaF2 layers containing Sm dopant ions. Some indications on the resonant tunneling of electrons from sharp silicon tip through dopant samarium ions inside the coating have been observed, which can be regarded as an implementation of one-atom electron source of a new type, based on dielectric coating of emitting tip.


Fig.1 Illustrating the resonant tunneling process from Si tip through dopant Sm ion in CaF2 coating on the tip surface. VB, CB - valence and conductance bands of Si, VL - vacuum level.


Fig.2 Field electron emission images of uncovered Si tip (a) and Si tip covered by 3nm thick CaF2:Sm epitaxial layer (b).