a1 email@example.com, TOYOTA Central R&D Laboratories, Inc., Nagakute, Japan
a2 firstname.lastname@example.org, TOYOTA Central R&D Laboratories, Inc., Nagakute, Japan
a3 email@example.com, TOYOTA Central R&D Laboratories, Inc., Nagakute, Aichi, Japan
We have investigated the effect of N doping into Cu2O films deposited by reactive magnetron sputtering. With increasing N-doping concentration up to 3 at.%, the optical bandgap energy is enlarged from ˜2.1 to ˜2.5 eV with retaining p-type conductivity as determined by optical absorption and Hall-effect measurements. Additionally, photoelectron spectroscopy in air measurements shows an increase in the valence and conduction band shifts with N doping. These experimental results demonstrate possible optical bandgap widening of p-type N-doped Cu2O films, which is a phenomenon that is probably associated with significant structural changes induced by N doping, as suggested from x-ray diffraction measurements.
(Received November 08 2009)
(Accepted December 31 2009)