Growth and Characterization of Zinc Oxide Thin Films for Light Emitting Diodes PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Growth and Characterization of Zinc Oxide Thin Films for Light Emitting Diodes PDF full book. Access full book title Growth and Characterization of Zinc Oxide Thin Films for Light Emitting Diodes by Hyun-Sik Kim. Download full books in PDF and EPUB format.
Author: Hyun-Sik Kim
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
ZnO-based light emitting diodes were fabricated on c-plane sapphire using ZnO:P/ Zn[subscript 0.9]Mg[subscript 0.1]O/ZnO/ Zn[subscript 0.9]Mg[subscript 0.1]O/ZnO:Ga p-i-n heterostructures. The p-i-n heterojunction diodes are rectifying and show light emission under forward bias. The electroluminescence spectra shows deep level emission at low bias, but near band edge ultraviolet emission at high voltage bias. A decrease in leakage currents in as-fabricated structures was achieved via low temperature oxygen annealing.
Author: Hyun-Sik Kim
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
ZnO-based light emitting diodes were fabricated on c-plane sapphire using ZnO:P/ Zn[subscript 0.9]Mg[subscript 0.1]O/ZnO/ Zn[subscript 0.9]Mg[subscript 0.1]O/ZnO:Ga p-i-n heterostructures. The p-i-n heterojunction diodes are rectifying and show light emission under forward bias. The electroluminescence spectra shows deep level emission at low bias, but near band edge ultraviolet emission at high voltage bias. A decrease in leakage currents in as-fabricated structures was achieved via low temperature oxygen annealing.
Author: Michelle Anne Myers
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Applications of zinc oxide (ZnO) for optoelectronic devices, including light emitting diodes, semiconductor lasers, and solar cells have not yet been realized due to the lack of high-quality p-type ZnO. In the research presented herein, pulsed laser deposition is employed to grow Ag-doped ZnO thin films, which are characterized in an attempt to understand the ability of Ag to act as a p-type dopant. By correlating the effects of the substrate temperature, oxygen pressure, and laser energy on the electrical and microstructural properties of Ag-doped ZnO films grown on c-cut sapphire substrates, p-type conductivity is achieved under elevated substrate temperatures. Characteristic stacking fault features have been continuously observed by transmission electron microscopy in all of the p-type films. Photoluminescence studies on n-type and p-type Ag-doped ZnO thin films demonstrate the role of stacking faults in determining the conductivity of the films. Exciton emission attributed to basal plane stacking faults suggests that the acceptor impurities are localized nearby the stacking faults in the n-type films. The photoluminescence investigation provides a correlation between microstructural characteristics and electrical properties of Ag- doped ZnO thin films; a link that enables further understanding of the doping nature of Ag impurities in ZnO. Under optimized deposition conditions, various substrates are investigated as potential candidates for ZnO thin film growth, including r -cut sapphire, quartz, and amorphous glass. Electrical results indicated that despite narrow conditions for obtaining p-type conductivity at a given substrate temperature, flexibility in substrate choice enables improved electrical properties. In parallel, N+-ion implantation at elevated temperatures is explored as an alternative approach to achieve p-type ZnO. The ion implantation fluence and temperature have been optimized to achieve p-type conductivity. Transmission electron microscopy reveals that characteristic stacking fault features are present throughout the p-type films, however in n-type N-doped films high-density defect clusters are observed. These results suggest that the temperature under which ion implantation is performed plays a critical role in determining the amount of dynamic defect re- combination that can take place, as well as defect cluster formation processes. Ion implantation at elevated temperatures is shown to be an effective method to introduce increased concentrations of p-type N dopants while reducing the amount of stable post-implantation disorder. Finally, the fabrication and properties of p-type Ag-doped ZnO/n-type ZnO and p-type N-doped ZnO/n-type ZnO thin film junctions were reported. For the N-doped sample, a rectifying behavior was observed in the I-V curve, consistent with N-doped ZnO being p-type and forming a p-n junction. The turn-on voltage of the device was -2.3 V under forward bias. The Ag-doped samples did not result in rectifying behavior as a result of conversion of the p-type layer to n-type behavior under the n- type layer deposition conditions. The systematic studies in this dissertation provide possible routes to grow p-type Ag-doped ZnO films and in-situ thermal activation of N-implanted dopant ions, to overcome the growth temperature limits, and to push one step closer to the future integration of ZnO-based devices. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149354
Author: Chennupati Jagadish
Publisher: Elsevier
ISBN: 0080464033
Category : Science
Languages : en
Pages : 600
Get Book Here
Book Description
With an in-depth exploration of the following topics, this book covers the broad uses of zinc oxide within the fields of materials science and engineering: - Recent advances in bulk , thin film and nanowire growth of ZnO (including MBE, MOCVD and PLD), - The characterization of the resulting material (including the related ternary systems ZgMgO and ZnCdO), - Improvements in device processing modules (including ion implantation for doping and isolation ,Ohmic and Schottky contacts , wet and dry etching), - The role of impurities and defects on materials properties - Applications of ZnO in UV light emitters/detectors, gas, biological and chemical-sensing, transparent electronics, spintronics and thin film
Author: Paolo Mele
Publisher:
ISBN: 9781536160864
Category : Zinc oxide thin films
Languages : en
Pages : 0
Get Book Here
Book Description
Zinc oxide (ZnO) is an n-type semiconductor with versatile applications such as optical devices in ultraviolet region, piezoelectric transducers, transparent electrode for solar cells and gas sensors. This book "ZnO Thin Films: Properties, Performance and Applications" gives a deep insight in the intriguing science of zinc oxide thin films. It is devoted to cover the most recent advances and reviews the state of the art of ZnO thin films applications involving energy harvesting, microelectronics, magnetic devices, photocatalysis, photovoltaics, optics, thermoelectricity, piezoelectricity, electrochemistry, temperature sensing. It serves as a fundamental information source on the techniques and methodologies involved in zinc oxide thin films growth, characterization, post-deposition plasma treatments and device processing. This book will be invaluable to the experts to consolidate their knowledge and provide insight and inspiration to beginners wishing to learn about zinc oxide thin films.
Author: Jau-Jiun Chen
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
ABSTRACT: ZnO-based materials have great potential for UV light-emitting diodes (LEDs) and transparent electronics because of the high exciton binding energy of ZnO relative to GaN. Fabricating an effective LED from novel materials requires a detailed knowledge of the band offset, etch, and contact behavior of the material. This work determined the valence and conduction band offsets for Zn095Cd0.05O/ZnO (0.17 eV, 0.30 eV) and related materials using x-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). These methods were also used to study carrier confinement in two promising passivation materials: MgO/GaN (1.06 eV, 3.30 eV) and Sc2O3/GaN (0.42 eV, 2.14 eV). To form an LED mesa, it is critical to understand the etch rate of ZnO-based materials. In this work, HCl and H3PO4 were used as etchants for ZnCdO/ZnO (~50 nm·1-min−1 HCl/~15 nm·min−1 H3PO4) and ZnMgO/ZnO (300-1100 nm·min−1 HCl/120-300 nm·min−1H3PO4). A high degree of selectivity was sought using these etchants on ZnCdO/ZnO (~50 HCl/~15 H3PO4) and ZnMgO/ZnO (~300-400 HCl/~25 H3PO4). Alloyed Ti/Au and Ti/Al/Pt/Au contacts were deposited on n-type Zn095Cd0.05O, with excellent contact resistivities of and 2.3x10−4 and 1.6x10−4 ohm-cm2, respectively. Alloyed Ti/Au and indium-tin-oxide (ITO)/Ti/Au metallization of n-type Al-doped ZnO was used to create ohmic metal contacts with excellent contact resistivities of 6x10−8 and 4.6x10−6ohm-cm2. Using SiLENSe Software, the optimum active layer thickness was found to be 200 nm.
Author: Tammy Ben-Yaacov
Publisher:
ISBN: 9781124365916
Category :
Languages : en
Pages : 236
Get Book Here
Book Description
In summary, this thesis describes the growth of ZnO(0001) films by MOCVD, the progress in developing ZnO material with excellent surface morphology, high crystal quality, and controllable n-type doping, as well as its application to GaN-based optoelectronic devices as a p-contact material.
Author: Zhe Chuan Feng
Publisher: CRC Press
ISBN: 1000687147
Category : Science
Languages : en
Pages : 449
Get Book Here
Book Description
Through their application in energy-efficient and environmentally friendly devices, zinc oxide (ZnO) and related classes of wide gap semiconductors, including GaN and SiC, are revolutionizing numerous areas, from lighting, energy conversion, photovoltaics, and communications to biotechnology, imaging, and medicine. With an emphasis on engineering a
Author: Norbert H. Nickel
Publisher: Springer Science & Business Media
ISBN: 140203475X
Category : Science
Languages : en
Pages : 245
Get Book Here
Book Description
Recently, a significant effort has been devoted to the investigation of ZnO as a suitable semiconductor for UV light-emitting diodes, lasers, and detectors and hetero-substrates for GaN. Research is driven not only by the technological requirements of state-of-the-art applications but also by the lack of a fundamental understanding of growth processes, the role of intrinsic defects and dopants, and the properties of hydrogen. The NATO Advanced Research Workshop on “Zinc oxide as a material for micro- and optoelectronic applications”, held from June 23 to June 25 2004 in St. Petersburg, Russia, was organized accordingly and started with the growth of ZnO. A variety of growth methods for bulk and layer growth were discussed. These techniques comprised growth methods such as closed space vapor transport (CSVT), metal-organic chemical vapor deposition, reactive ion sputtering, and pulsed laser deposition. From a structural point of view using these growth techniques ZnO can be fabricated ranging from single crystalline bulk material to polycrystalline ZnO and nanowhiskers. A major aspect of the ZnO growth is doping. n-type doping is relatively easy to accomplish with elements such al Al or Ga. At room temperature single crystal ZnO exhibits a resistivity of about 0. 3 -cm, an electron mobility of 2 17 -3 225 cm /Vs, and a carrier concentration of 10 cm . In n-type ZnO two shallow donors are observable with activation energies of 30 – 40 meV and 60 – 70 meV.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 4
Get Book Here
Book Description
Author: Pierre Souletie
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
