Influence of annealing temperature on nickel oxide thin films grown by chemical bath deposition. (December 2017)

• Record Type: Journal Article
• Authors: Martínez-Gil, M.; Pintor-Monroy, M.I.; Cota-Leal, M.; Cabrera-German, D.; Garzon-Fontecha, A.; Quevedo-López, M.A.; Sotelo-Lerma, M.
• Is Part Of: Materials science in semiconductor processing. Volume 72(2017)
• Page Start: 37
• Page End: 45
• Publication Date: 2017-12
• Subjects: Nickel oxide -- p-type -- Chemical bath deposition -- XPS -- Band diagram; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2017.09.021
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: Nickel oxide thin films were prepared with a simple formulation using nickel sulfate and triethanolamine aqueous solutions via chemical bath deposition. After deposition, the films were subjected to annealing in an O2 /N2 atmosphere for two hours at 200, 300, and 400 °C. X-ray diffraction patterns indicated that the as-deposited NiO x films were amorphous. After annealing, the NiO x crystallizes into a cubic phase. The X-ray photoelectron spectroscopy analysis confirms the presence of NiO x with an FCC phase that yields a chemical composition of NiO1.17, without the appearance of other Ni compounds. The band gap for the NiO x films is determined to lie between 4.0 and 3.4 eV. Scanning electron micrographs exhibit a compact deposition and worm-like structure morphology. Hall effect measurements indicate a p -type conductivity and the resistivity is found to vary from 1.73 × 10 3 to 0.89 × 10 6 Ω cm due to oxygen incorporation. Employing Kelvin probe microscopy and photoemission spectroscopy, the NiO x films present a work function between 4.70 and 5.48 eV and an ionization energy of ~ 5.6 eV. From the work function, ionization energy, and the band gap results, we propose a band diagram for the films at different annealing temperatures.