Poole‐Frenkel Conduction Mechanism in ZnO:N Nanobelts

In this paper, the authors demonstrate that the electrical conduction along ZnO:N nanobelts follow a conduction mechanism type Poole‐Frenkel. Electrical measurements obtained using the conductive‐AFM (C‐AFM) technique and between two In/W electrodes of single ZnO:N nanobelts confirm this result. These measurements reveal that the dielectric constant, ϵ r , of the ZnO nanobelts, is about 4.3. Cathodoluminescence (CL) spectra acquired from single ZnO:N nanobelts show a strong signal centered at 3.23, with two‐phonon replicas at 3.15 and 3.08 eV, generated by a donor‐acceptor pair (DAP) transition besides a signal centered at 3.29 eV corresponding with a free electron‐acceptor (FA) transition. The authors propose the presence of N O as acceptor centers to explain the origin of these electronic transitions. X‐ray photoelectron spectroscopy measurements confirm the presence of this substitutional impurity, revealing an N 1s signal corresponding with ZnN bonds. The authors propose that N O acceptor centers participate as defect traps that originate the Poole‐Frenkel conduction mechanism.