PENCIL LEAD FIELD EMITTER

Field electron emission from 2H and HB grades of pencil lead has been studied. The pencil lead field emitter is found to obey the Fowler-Nordheim characteristics. The emission current fluctuations are found to increase with the residual gas pressure and the emission current. The current density of the order of 106 amp/cm2 could be drawn from these emitters. The emission stability over the operation of six hours has been found to be reasonably good. The field ion microscopy of the 2H and HB grade pencil lead has been carried out depicting the lesser degree of graphitization in the 2H grade in comparison with the HB grade. A comparison of the two grades of emitters has been made in view of the respective degrees of graphitization

FIELD ELECTRON EMISSION FROM METALLIC GLASS

The paper reports investigations on field electron emission from Fe70Cr5Si10B15 metallic glass. Fowler-Nordheim (F-N) characteristics are obtained under different conditions of field evaporation. Linearity of the F-N plots and the nature of the ultra-violet photoelectron spectrum show the nearly free electron like nature of the metallic glass. The observed temperature dependence of the field emission current with dc and pulse field evaporation is explained on the basis of compositional variation in the surface and its "imperfect" nature, to a certain extent. These results are supplemented by field ion microscopic observations and discussed in view of the recent atom probe work by several authors. Current densities of the order of 109A/sq.cm. have been observed and attributed largely to the isotropic emission and the enhanced field factor due to surface roughness

THE EFFECT OF SUBSTRATE TEMPERATURE ON THE BEHAVIOUR OF GOLD AND SILVER ON THE 100 TUNGSTEN PLANE

Pour reconcilier les caractéristiques travail de sortie (Φ) / couverture (θ) obtenues par Jones et Roberts [3] et celles de Richter et Gomer [2] nous avons étudié les caractéristiques Φ - θ en fonction des doses et de la température. Le traitement thermique est un facteur important. Pour relier ce travail à celui de Bauer et al. [1], de Sidorski et al. [6], nous avons aussi étudié la variation de Φ introduite par la condensation d'or et d'argent sur W(100) à haute température. Nous mettons ainsi en évidence la formation d'alliage en surface.In an effort to reconcile the work function (Φ) and coverage (θ) characteristics obtained by Jones and Roberts [3] with those of Richter and Gomer [2] we have studied the dependence of the Φ - θ characteristic on dose and temperature, and find thermal treatment to be the determining factor. To make contact with similar work by Bauer et al [1] and Sidorski et al [6] we have also studied changes in Φ induced when gold and silver are condensed on W(100) at high temperature, and find some evidence for formation of surface alloys

Low threshold field electron emission from solvothermally synthesized WO2.72 nanowires

10.1007/s00339-009-5536-0Applied Physics A: Materials Science and Processing984751-756APAM