Mw. Geis et al., ELECTRON FIELD-EMISSION FROM DIAMOND AND OTHER CARBON MATERIALS AFTERH-2, O-2 AND CS TREATMENT, Applied physics letters, 67(9), 1995, pp. 1328-1330
This letter reports, diamond field emitters, Cs treated, air stable, t
hat emit electrons at the lowest reported field, <0.2 V mu m(-1). Fiel
d emission from B-, Li-, P-, and N-doped diamonds and carbonized polym
er was characterized as a function of surface treatment. A treated wit
h an O-2 plasma, coated with Cs, heated, and exposed to O-2 exhibited
increased emission for all samples except for B-doped diamond. The bes
t emission was obtained from N-doped diamond samples, followed by carb
onized polymer, the Li-doped, and polycrystalline P-doped diamond. Li-
and N-doped samples treated with Cs were stable in laboratory air for
several days. This stability of the surface-activated diamond is beli
eved to be due to the formation of a diamond-O-Cs salt. If the sample
is treated with a H-2 plasma instead of an O-2 plasma, the Cs-enhanced
emission degrades with heat and exposure to O-2. Subbands formed by L
i and N impurities are believed to be responsible for this enhanced em
ission. The surface treatment on N-doped diamond results in emission a
t fields as low as 0.2 V mu m(-1). (C) 1995 American Institute of Phys
ics.