Temperature and substrate effect on the electrical and structural properties of NiO columnar nanostructure

NiO columnar nanostructure has been grown by simultaneous deposition of thermal evaporation and oblique angle deposition (OAD) on stainless steel and glass substrates. The structural properties of NiO columnar nanostructure on both substrates were investigated. The electrical properties of NiO columnar nanostructure on both substrates were investigated by the Hall effect. Thin films on glass substrate showed rough surfaces with irregular distribution of grains, while those on steel substrate showed rough surfaces and flower-like grains with uniform distribution. At temperatures below 410 degrees K, the resistivity and mobility of NiO columnar nanostructure on both substrates decreased. The resistivity decreased and mobility increased with increasing temperature for NiO thin films on steel and glass at a temperature range of 410-470 degrees K and 410-520 degrees K, respectively. At higher temperatures, the resistivity of NiO thin film on steel decreased with temperature, while the resistivity and mobility of NiO thin film on glass remained almost constant.