Acceptor-modulated optical enhancements and band-gap narrowing in ZnO thin films

Abstract

Fermi-Dirac distribution for doped semiconductors and Burstein-Moss effect have been correlated first time to figure out the conductivity type of ZnO. Hall Effect in the Van der Pauw configuration has been applied to reconcile our theoretical estimations which evince our assumption. Band-gap narrowing has been found in all p-type samples, whereas blue Burstein-Moss shift has been recorded in the n-type films. Atomic Force Microscopic (AFM) analysis shows that both p-type and n-type films have almost same granular-like structure with minor change in average grain size (∼ 6 nm to 10 nm) and surface roughness rms value 3 nm for thickness ∼315 nm which points that grain size and surface roughness did not play any significant role in order to modulate the conductivity type of ZnO. X-ray diffraction (XRD), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Photoelectron Spectroscopy (XPS) have been employed to perform the structural, chemical and elemental analysis. Hexagonal wurtzite structure has been observed in all samples. The introduction of nitrogen reduces the crystallinity of host lattice. 97% transmittance in the visible range with 1.4 × 107 Ω-1cm-1 optical conductivity have been detected. High absorption value in the ultra-violet (UV) region reveals that NZOs thin films can be used to fabricate next-generation high-performance UV detectors.

Effect of NiOx’s film thickness on the electrical properties of Ni/p–NiOx/n-Si structures

“…Because of this, the existence probability of holes in the valence band is higher than conduction band. A similar deviation in Fermi level position was explained by other authors [54]. Therefore, increasing the quasi-Fermi level of the majority of carriers on n-Si may be shown as the reason for the increase of barrier height value with the increasing film thickness.…”

Structure, microstructure, optical and photocatalytic properties of Mn-doped ZnO nanoparticles

“…High radiation properties, thermal and chemical resistance make ZnO a preferable material in the transparent contacts of solar cells. Besides these features, ZnO and its doped forms are used in acoustic, magnetic, electric, optic, cosmetic, and nuclear applications [7][8][9][10][11].…”

Effects of Thallium–Aluminum‐Codoped Zinc Oxide Thin Film as a New Transparent Conducting Oxide

“…This results in carrier concentrationdependent effective mass. [53][54][55][56][57] To check the accuracy of the results obtained in the Tauc model, the new derivation of the absorption spectrum fitting (DASF) method [58] in Figure 6 was used by which the optical bandgap directly can be determined using E gap ¼ 1240/λ g , in which λ g can be reached by a discontinuity in the…”