Physical properties of thin-film field emission cathodes with molybdenum cones

Journal Article · Wed Dec 01 04:00:00 EST 1976 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.322600· OSTI ID:7337897

Spindt, C A; Brodie, I; Humphrey, L; Westerberg, E R

Field emission cathodes fabricated using thin-film techniques and electron beam microlithography are described, together with effects obtained by varying the fabrication parameters. The emission originates from the tip of molybdenum cones that are about 1.5 ..mu..m tall with a tip radius around 500 A. Such cathodes have been produced in closely packed arrays containing 100 and 5000 cones as well as singly. Maximum currents in the range 50--150 ..mu..A per cone can be drawn with applied voltages in the range 100--300 V when operated in conventional ion-pumped vacua at pressures of 10/sup -9/ torr or less. In the arrays, current densities (averaged over the array) of above 10 A/cm/sup 2/ have been demonstrated. Life tests with the 100-cone arrays drawing 2 mA total emission (or 3 A/cm/sup 2/) have proceeded in excess of 7000 h with about a 10% drop in emission current. Studies are presented of the emission characteristics and current fluctuation phenomena. It is tentatively concluded that the emission arises from only one or a few atomic sites on the cone tips. (AIP)

• Research Organization: Stanford Research Institute, Menlo Park, California 94025
• OSTI ID: 7337897
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 47:12; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
CATHODES
ELECTRODES
ELEMENTS
EMISSION
FABRICATION
FIELD EMISSION
FILMS
METALS
MOLYBDENUM
NOISE
REFRACTORY METALS
STABILITY
TRANSITION ELEMENTS