Journal ArticleDOI
Excitonic structure and absorption coefficient measurements of ZnO single crystal epitaxial films deposited by pulsed laser deposition
TLDR
In this paper, the optical properties of high quality single crystal epitaxial zinc oxide thin films grown by pulsed laser deposition on c-plane sapphire substrates were studied.Abstract:
The optical properties of high quality single crystal epitaxial zinc oxide thin films grown by pulsed laser deposition on c-plane sapphire substrates were studied. It was found that annealing the films in oxygen dramatically improved the optical and electrical properties. The absorption coefficient, band gap, and exciton binding energies were determined by transmission measurements and photoluminescence. In both the annealed and the as-deposited films excitonic absorption features were observed at both room temperature and 77 K. In the annealed films the excitonic absorption peaks were substantially sharper and deep level photoluminescence was suppressed.read more
Citations
More filters
Journal ArticleDOI
A comprehensive review of zno materials and devices
Ümit Özgür,Ya. I. Alivov,C. Liu,A. Teke,Michael A. Reshchikov,Seydi Doğan,Vitaliy Avrutin,Sang-Jun Cho,Hadis Morkoç +8 more
TL;DR: The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature.
Journal ArticleDOI
ZnO : From basics towards applications
TL;DR: In this article, the authors review the fundamental properties of ZnO and of ZNO-based nanostructures, doping as well as present and future applications with emphasis on the electronic and optical properties including stimulated emission.
Journal ArticleDOI
ZnO: Material, Physics and Applications
TL;DR: This work critically review aspects of the material growth, fundamental properties of ZnO and ZNO-based nanostructures and doping as well as present and future applications with emphasis on the electronic and optical properties including stimulated emission.
Journal ArticleDOI
Titanium dioxide and zinc oxide nanoparticles in sunscreens: focus on their safety and effectiveness
TL;DR: Caution should still be exercised when new sunscreens are developed and research that includes sunscreen NP stabilization, chronic exposures, and reduction of NPs' free-radical production should receive full attention.
Journal ArticleDOI
Blue luminescent centers and microstructural evaluation by XPS and Raman in ZnO thin films annealed in vacuum, N2 and O2
TL;DR: In this paper, the defects of ZnO thin films prepared on sapphire substrates by employing a pulsed laser deposition (PLD) have been annealed in vacuum, N 2, and O 2 ambient at annealing temperature 600 ˚ C.
References
More filters
Journal ArticleDOI
Optically pumped lasing of ZnO at room temperature
TL;DR: In this paper, the authors reported the observation of optically pumped lasing in ZnO at room temperature using a plasma-enhanced molecular beam epitaxy on sapphire substrates.
Journal ArticleDOI
Room-temperature ultraviolet laser emission from self-assembled ZnO microcrystallite thin films
TL;DR: In this article, room-temperature ultraviolet (UV) laser emission of ZnO microcrystallite thin films is reported, which represents an important step towards the development of nanometer photoelectronics.
Journal ArticleDOI
Intensity of Optical Absorption by Excitons
TL;DR: In this paper, the intensity of optical absorption close to the edge in semiconductors is examined using band theory together with the effective-mass approximation for the excitons, and the experimental results on O and Ge are in good qualitative agreement with direct forbidden and indirect transitions, respectively.
PatentDOI
Blue-green laser diode
TL;DR: In this article, a II-VI compound semiconductor laser diode is formed from overlaying layers of material including an n-type single crystal semiconductor substrate (12), adjacent N-type and p-type guiding lasers (14), a quantum well active layer (18), and a second electrode (30) is characterized by a Fermi energy, with shallow acceptors having a shallow acceptor energy, to a net acceptor concentration of at least 1 x 1017 cm 3.
Journal ArticleDOI
On the optical band gap of zinc oxide
V. Srikant,David R. Clarke +1 more
TL;DR: In this paper, the optical properties of ZnO crystals using a variety of optical techniques were compared and it was concluded that the room temperature band gap is 3.3 eV and that the other values are attributable to a valence band-donor transition at ∼3.15