Effect of Annealing in Physical Properties of NiO Nanostructure Thin Film

Abstract

Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the average of the crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found 46.62 for as-deposited sample and 119.89 nm for the annealed one. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging ranging 3.64 for as-deposited sample and 2.98 eV for the annealed one. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.09241 (•cm) −1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity.

Investigation of the physical properties of nanostructured CO:NiO thin films

“…The values of band gap Eg is 3.61 eV for undoped sample, whereas the values of E g gradually decreases from 3.60 to 3.48 eV for Co-doped samples from 3 to 12 at.%. This is in good agreement with previous research reports by different groups [27,28], where they found that the bandgap of NiO films varies between 3.4 eV and 4.0 eV. The band gap is found to decrease with an increase in the Co doping concentration; this suggests a change in the NiO electronic structure i.e the suggests a change in the crystallite growth, defects or vacancies in the NiO crystal which can create new energy levels.…”

Élaboration et caractérisation des couches minces d'oxydes conducteurs transparents (TCO) pour les cellules solaires

“…Le mélange est agité à 60°C pendant 2heures pour obtenir une eau limpide et une solution homogène puis le mélange a été refroidi à optique des films minces obtenus est de 3,64 eV et de 2,98 eV respectivement des échantillons non recuits et ceux recuits. La conductivité de l'échantillon non recuit est de l'ordre de 0,04125 𝛺 −1 cm -1 et celle de l'échantillon recuit est de 0,09241 𝛺 −1 cm -1[74]. Universitat Politècnica de València / Instituto Diseño y Fabricación (IDF)…”