Abstract:
Pd-F:SnO2 thin films have been prepared by spray pyrolysis technique.
Optimization has been done by doping SnO2 with palladium at varying levels of
concentration and then recording sheet resistance. The sheet resistivity has been observed to
decrease gradually as at% Pd concentration is increased; an optimum sheet resistivity value
of 2.71 × 10−2 Ω cm has been recorded. The decrease in sheet resistivity has been attributed
to presence of Pd ions which contribute in increment of charge carrier density. Using the
optimum value of at% Pd doping, the same procedure has been repeated to study the effect
of fluorine on Pd:SnO2; an optimum value of 1.64 × 10−4 Ω cm sheet resistivity has been
recorded. This decrease has been attributed to substitution of O−
with those of fluorine hence
improving charge carrier density. The effect of passivation has been studied by comparing
as prepared, annealed and passivated Pd-F:SnO2 thin films. Annealing has been observed to
decrease the sheet resistivity to 1.21 × 10−4 Ω cm, while passivation has the effect of increasing the sheet resistivity to 1.53 × 10−4 Ω cm which is attributed to effects resulting
from annealing the samples in nitrogen gas atmosphere.
