Valence and conduction band offset measurements in Ni0.07Zn0.93O/ZnO heterostructure

• The band offset measurement is carried out using XPS measurements.
• Spin polarize transport is observed from magnetotransport measurements.
• The barrier height for transport of electrons is smaller than that of holes.
• Type II band alignment at the interface of the heterostructure is observed.

We report valence and conduction band offset measurements in a pulsed laser deposited Ni0.07Zn0.93O/ZnO heterostructure using X-ray photoelectron spectroscopy, valence band spectroscopy and ultraviolet visible spectroscopy. Neglecting the strain effect, the valence band offset was estimated to be 0.32 eV and the conduction band offset comes out to be −0.23 eV. Ratio between conduction band and valence band offset is 0.72. Core level shifting due to Ni doping has also been explained. Magnetotransport study of Ni0.07Zn0.93O film reveals that the charge carriers might be spin polarized at the interface of the heterojunction.