A comprehensive review of ZnO materials and devices
Top Cited Papers
- 15 August 2005
- journal article
- review article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 98 (4), 041301
- https://doi.org/10.1063/1.1992666
Abstract
The semiconductorZnO has gained substantial interest in the research community in part because of its large exciton binding energy ( 60 meV ) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p -type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev.142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys.6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. Lett.16, 439 (1970)]. In terms of devices, Au Schottky barriers in 1965 by Mead [Phys. Lett.18, 218 (1965)], demonstration of light-emitting diodes (1967) by Drapak [Semiconductors2, 624 (1968)], in which Cu 2 O was used as the p -type material, metal-insulator-semiconductor structures (1974) by Minami et al. [Jpn. J. Appl. Phys.13, 1475 (1974)], Zn O ∕ Zn Se n - p junctions (1975) by Tsurkan et al. [Semiconductors6, 1183 (1975)], and Al ∕ Au Ohmic contacts by Brillson [J. Vac. Sci. Technol.15, 1378 (1978)] were attained. The main obstacle to the development of ZnO has been the lack of reproducible and low-resistivity p -type ZnO, as recently discussed by Look and Claflin [Phys. Status Solidi B241, 624 (2004)]. While ZnO already has many industrial applications owing to its piezoelectric properties and band gap in the near ultraviolet, its applications to optoelectronic devices has not yet materialized due chiefly to the lack of p -type epitaxial layers. Very high quality what used to be called whiskers and platelets, the nomenclature for which gave way to nanostructures of late, have been prepared early on and used to deduce much of the principal properties of this material, particularly in terms of optical processes. The suggestion of attainment of p -type conductivity in the last few years has rekindled the long-time, albeit dormant, fervor of exploiting this material for optoelectronic applications. The attraction can simply be attributed to the large exciton binding energy of 60 meV of ZnO potentially paving the way for efficient room-temperature exciton-based emitters, and sharp transitions facilitating very low threshold semiconductor lasers. The field is also fueled by theoretical predictions and perhaps experimental confirmation of ferromagnetism at room temperature for potential spintronics applications. This review gives an in-depth discussion of the mechanical, chemical, electrical, and optical properties of ZnO in addition to the technological issues such as growth, defects, p -type doping, band-gap engineering, devices, and nanostructures.Keywords
This publication has 584 references indexed in Scilit:
- Optical investigations on excitons bound to impurities and dislocations in ZnOOptical Materials, 2003
- Coordination-Number Dependence of Magnetic Hyperfine Fields aton Ni SurfacesPhysical Review Letters, 2002
- High spatial resolution thermal conductivity of bulk ZnO (0001)Journal of Applied Physics, 2002
- Physical and structural properties of ZnO sputtered filmsMaterials Letters, 2001
- Elastic and high pressure properties of ZnOJournal of Applied Physics, 1998
- A generic ionic potential for the alkaline-earth oxides and the anomalous crystal structure of ZnOMolecular Physics, 1997
- Preparation and some properties of nitrogen-mixed ZnO thin filmsThin Solid Films, 1996
- Renormalization scheme for the transfer-matrix method and the surfaces of wurtzite ZnOPhysical Review B, 1981
- The phase behavior of simple compoundsPhysics of the Earth and Planetary Interiors, 1970
- Quantentheoretische Beitr ge zum BenzolproblemThe European Physical Journal A, 1931