The piezoelectric potential of ZnO can be enhanced using acceptor dopants to neutralize the donor concentrations. In this study, unintentional n-type conductivity is assessed through modeling ZnO nanowires where the activation process of donors (Nd+) is given with a Fermi level (EF) close to the conduction band and followed by the introduction of an acceptor dopant (Na-) in order to allow EF to be within the optimum range of 1 ≤ EF ≤ 3.2 eV, which corresponds to the maximum piezoelectric potential calculated. The finite element method simulation reveals that the maximal range of ZnO piezoelectric potential can be obtained due to the intrinsic characteristics of the ZnO nanowire transformed using acceptor dopants, which implies that the limitations on the free-charge carriers (i.e. free-carrier depletion) could reduce the screening effects on the piezoelectric potential. Furthermore, the difference | Nd+ - a- | is calculated to approach zero near the mid-gap and the energy band structure, which deviates from the normal flat line within the optimal range of 1 ≤ EF ≤ 3.2 eV 3.2 eV under the external stress imposed.
|Number of pages||7|
|Journal||Journal of Computational Electronics|
|Publication status||Published - 2014 Sept|
Bibliographical noteFunding Information:
Acknowledgments This work was supported by the Computational Energy Harvesting (CEH) project in Samsung Advanced Institute of Technology. This research was supported by National Research Foundation of Korea (NRF) grants funded by the Ministry of Science, ICT & Future Planning (2009-0083540) and the Energy International Collaboration Research & Development Program of the Korea Institute of Energy Technology Evaluation and Planning funded by the Ministry of Knowledge Economy (2011-8520010050).
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Modelling and Simulation
- Electrical and Electronic Engineering