Oxidation and Reduction Behavior in Donor-Doped BaSnO
3
Thin Films
Michael Campion
1
and Harry Tuller
217-714-0434, Office 13-4010, 32 Vassar Street, Cambridge, MA 02139
BaSnO
3
is an attractive alternative in transparent conducting applications due to its wide band
gap and low electron effective mass. In many cases, The electrical conductivity of n-type
transparent conducting oxides has previously been demonstrated to be strongly correlated to
the oxygen activity present in the film from film formation or processing. For other
transparent conducting oxides, this has been shown to be attributable to intrinsic defect
compensation and grain boundary blocking effects. These effects have not yet been
systematically investigated for donor-doped BaSnO
.
In this study, the oxidation and
reduction behavior of undoped and donor-doped BaSnO
3
is investigated with respect to its
optical and electrical properties. Both epitaxial and polycrystalline thin films fabricated via
pulsed laser deposition are investigated under varying oxygen activities. These experiments
are performed through ex situ optical transmission measurements after oxidizing and
reducing annealing conditions accompanied by in situ electrical measurements during
controlled atmosphere annealing. From this data, a model of the oxidation and reduction
process of BaSnO
3
can be constructed taking into account both the effects of defect
compensation and non-stoichiometric grain boundaries. This new information will lead to a
greater fundamental understanding of this transparent conducting oxide as well as more
informed choices of fabrication and processing conditions for BaSnO
3
containing devices.
O 30
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