Discontinuous and continuous diamond films with different morphologies and
qualities were deposited on n(2+)-type Si(100) substrates, using the hot fi
lament chemical vapor deposition (CVD) technique from CH4-H-2 gas mixtures.
The field-emission characteristics of these diamond films were investigate
d. The turn-on fields at a 0.01 mA/cm(2) current density were recorded for
all the tested CVD-diamond films. It was found that discontinuous diamond f
ilms showed a much lower turn-on field (1.2 V/mu m) than continuous ones (2
0 V/mu m). The effective working function of continuous diamond films was a
round 0.1 eV, while that for discontinuous diamond films is about 0.03 eV.
O-2 plasma post-deposition sharpening of thick diamond films indicated that
the geometrical-field enhancement caused by the surface topographic change
s, has no significant influence on the turn-on field. (C) 2000 Elsevier Sci
ence S.A. All rights reserved.