Aerosol-assisted CVD of nickel oxide on silicon for hole selective contact layers.

Nickel oxide (NiO_x) is an optimum material for hole selective contacts and is extensively used in multiple photovoltaic technologies. The deposition of nickel oxide for photovoltaic applications is primarily performed with sputtering. In this paper, we will report on the deposition of nickel oxide thin film with aerosol-assisted chemical vapor deposition (AACVD). Nickel nitrate hexahydrate was used as the nickel salt while the deposition was performed at 550 °C for a time of 15 min. The thin films as obtained showed a uniform surface morphology with a thickness of about 15 nm and a grain size of 40 nm. The AFM results showed a surface with a root-mean square surface roughness value varying between 1.69 to 2.23 nm. The XPS analysis showed that the NiO_x layer is slightly non-stoichiometric with a slight excess of oxygen and can be denoted as NiO_1.05. The current–voltage measurements showed a diode-like behaviour with a current density of 4.54 mA/cm² obtained at 1 V. The combination of developing NiO_x thin films with AACVD on silicon and using nickel nitrate as precursor along with showing the diode characteristics provide the novelty of this work. [ABSTRACT FROM AUTHOR]