Abstract
Transparent and conducting epitaxial thin films of pristine chromium oxide (Cr2O3) and nickel (Ni) substituted Cr2O3 were deposited on the sapphire substrates using pulsed laser deposition (PLD) technique. Co-precipitation method was used to prepare targets of Cr2O3 nanomaterials with varying Ni content (i.e. x = 0, 0.03, 0.05 and 0.1). In-plane diffraction (i.e. ϕ-scan) measurements confirmed that all thin films were epitaxially grown on sapphire substrates. X-ray diffraction (XRD) patterns illustrated that all thin films orienting along (006) plane only and crystallize in the rhombohedral structure of Cr2O3, and structure remains unchanged with Ni-substitution. Consequently, Cr cations were replaced by Ni counter-cations in Cr2O3 structure, which lead to the delocalization of holes and improve mobility. Moreover, an increase in Ni-content also leads to upsurge in the carrier concentration. Hence, both factors contributed to the improvement in Ni-substituted Cr2O3 thin films' conductivity and retained the p-type character as well. UV–Vis spectra demonstrated that pristine Cr2O3 thin film acquired an optical band gap energy of 3.64 eV, decreasing to 3.48 eV with Ni-substitution. Furthermore, optical transmittance spectra illustrated the average transparency of 77–81% for as-deposited thin films in the visible region. Therefore, this material can render a wide variety of applications in the field of optoelectronics.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have