Mw. Geis et al., COMPARISON OF ELECTRIC-FIELD EMISSION FROM NITROGEN-DOPED, TYPE LB DIAMOND, AND BORON-DOPED DIAMOND, Applied physics letters, 68(16), 1996, pp. 2294-2296
Field emission of electrons from boron- and nitrogen-doped diamond is
compared. Emission from boron-doped diamond requires vacuum electric f
ields of 20-50 V mu m(-1), while nitrogen-doped, type Ib diamond requi
res fields of 0-1 V mu m(-1). Since boron-doped diamond is very conduc
tive, very little voltage drop occurs in the diamond during emission.
Nitrogen-doped diamond is insulating, so during emission a potential o
f 1-10 kV appears in the diamond. This potential is a function of the
back contact metal-diamond interface. A roughened interface substantia
lly reduces the potential in the diamond and increases emission. The e
lectrons are often emitted from the nitrogen-doped diamond as beamlets
. These beamlets leave the surface of the diamond at angles up to 45 d
egrees from the substrate normal. Although the vacuum field is small,
these electrons have energies of several kV. It is unknown whether the
electrons are accelerated to these energies in the bulk of the diamon
d, or at high electric fields near the emitting surface. (C) 1996 Amer
ican Institute of Physics.