Dy-doped CdO films were prepared and post-annealed in hydrogen atmosphere
for different durations (15 min, 30 min and 45 min). They were
characterised by measuring their structural, electrical, and optical
properties. The results indicate that annealing in H2 gas does not
change the crystalline CdO structure of the films. The electrical behaviours
of Dy-doped CdO films show that they are degenerate semiconductors with
bandgap 1.75 eV. The bandgap of the hydrogenated Dy-doped CdO films changes
with H2-annealing time following the changing in the carrier
concentration. These results were found to be in agreement with the
available models for bandgap widening and bandgap narrowing. The Dy-doping
of CdO films enhances their electrical conduction. An additional enhancement
was obtained with pre-annealing in H2 gas so that the greatest
enhancement occurs with annealing for 30 min. when the conductivity
increased by about 40% and the free-electrons concentration increased by
about 260% relative to the non-hydrogenated CdO:Dy film. From
transparent-conducting-oxide point of view, Dy is sufficiently effective for
CdO doping especially when including a pre-annealing in H2 atmosphere.