Field emission studies of the lanthanum hexaboride/tungsten system

Tungsten deposited with lanthanum hexaboride (LaB6) is of interest, as LaB6 is characterized by the properties of an excellent electron emitter. The authors report a field emission study of the LaB6/tungsten system prepared by depositing LaB6 in situ on to a tungsten tip. The observed maximum decrease in the average work-function was from 4.52 eV (clean tungsten) to 1.75 eV (LaB6 deposited on tungsten). The field emission pattern of tungsten deposited with LaB6 shows preferential adsorption around the (111) and (100) planes.