Epitaxial Growth and Characterization of GaAs on Spinel 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 Epitaxial Growth and Characterization of GaAs on Spinel PDF full book. Access full book title Epitaxial Growth and Characterization of GaAs on Spinel by Chih-Chun Wang. Download full books in PDF and EPUB format.
Author: Chih-Chun Wang Publisher: ISBN: Category : Languages : en Pages : 119
Book Description
Research on the epitaxial growth and characterization of GaAs on magnesium aluminate spinel has been carried out. Single crystal GaAs films (unintentionally doped) with thicknesses up to 70 micrometers have been grown on a spinel substrate using the vapor phase reaction between (CH3)3Ga and AsH3. The effect of growth conditions on the layer characteristics has been studied in order to achieve optimization of the film properties. Growth parameters studied include substrate orientation, substrate surface preparation, growth temperature, gas flow conditions, reactor geometry, and source material purification. The purity of the source material has been found to play a critically important role in determining both the crystallinity and the electrical properties of the films. Films with electron and hold mobilities up to, respectively, 4000 and 300 sq cm/V-sec have been prepared. Epitaxial growth of GaAs on GaAs/spinel composite using vapor phase and liquid phase techniques was explored with encouraging results. The epitaxial GaAs-spinel composites have been characterized by x-ray diffraction, electron diffraction, electron microscopy, and optical techniques. Information on the crystalline perfection, epitaxial orientation relationships, surface structures, and optical constants has been obtained. The overall single crystalline GaAs deposits are composed of crystallites which are misoriented by plus or minus 0.1 degree from the nominal orientation of the layer. The stress in the epitaxial GaAs was determined to be 1x10 to the 9th power dyne/sq cm. (Author).
Author: Chih-Chun Wang Publisher: ISBN: Category : Languages : en Pages : 119
Book Description
Research on the epitaxial growth and characterization of GaAs on magnesium aluminate spinel has been carried out. Single crystal GaAs films (unintentionally doped) with thicknesses up to 70 micrometers have been grown on a spinel substrate using the vapor phase reaction between (CH3)3Ga and AsH3. The effect of growth conditions on the layer characteristics has been studied in order to achieve optimization of the film properties. Growth parameters studied include substrate orientation, substrate surface preparation, growth temperature, gas flow conditions, reactor geometry, and source material purification. The purity of the source material has been found to play a critically important role in determining both the crystallinity and the electrical properties of the films. Films with electron and hold mobilities up to, respectively, 4000 and 300 sq cm/V-sec have been prepared. Epitaxial growth of GaAs on GaAs/spinel composite using vapor phase and liquid phase techniques was explored with encouraging results. The epitaxial GaAs-spinel composites have been characterized by x-ray diffraction, electron diffraction, electron microscopy, and optical techniques. Information on the crystalline perfection, epitaxial orientation relationships, surface structures, and optical constants has been obtained. The overall single crystalline GaAs deposits are composed of crystallites which are misoriented by plus or minus 0.1 degree from the nominal orientation of the layer. The stress in the epitaxial GaAs was determined to be 1x10 to the 9th power dyne/sq cm. (Author).
Author: G.W. Cullen Publisher: Springer Science & Business Media ISBN: 1461262674 Category : Technology & Engineering Languages : en Pages : 306
Book Description
Some years ago it was not uncommon for materials scientists, even within the electronics industry, to work relatively independently of device engi neers. Neither group had a means to determine whether or not the materials had been optimized for application in specific device structures. This mode of operation is no longer desirable or possible. The introduction of a new material, or a new form of a well known material, now requires a close collaborative effort between individuals who represent the disciplines of materials preparation, materials characterization, device design and pro cessing, and the analysis of the device operation to establish relationships between device performance and the materials properties. The develop ment of devices in heteroepitaxial thin films has advanced to the present state specifically through the unusually close and active interchange among individuals with the appropriate backgrounds. We find no book available which brings together a description of these diverse disciplines needed for the development of such a materials-device technology. Therefore, the authors of this book, who have worked in close collaboration for a number of years, were motivated to collect their experiences in this volume. Over the years there has been a logical flow of activity beginning with heteroepi taxial silicon and progressing through the III-V and II-VI compounds. For each material the early emphasis on material preparation and characteriza tion later shifted to an emphasis on the analysis of the device characteristics specific to the materials involved.
Author: J. W. Matthews Publisher: Elsevier ISBN: 1483271811 Category : Science Languages : en Pages : 315
Book Description
Epitaxial Growth Part B is the second part of a collection of review articles that describe various aspects of the growth of single-crystal films on single-crystal substrates. The topics discussed are the nucleation of thin films, the structure of the interface between film and substrate, and the generation of defects during film growth. The methods used to prepare and examine thin films are described and a list of the overgrowth-substrate combinations studied so far is given.
Author: Mahsa Mahtab Publisher: ISBN: Category : Languages : en Pages :
Book Description
GaAs(1-x)Bi(x) (x = 0 to 17%) optical properties were investigated by spectroscopic ellipsometry (in energy ranges of 0.37-9.0 eV). Optical features in the dielectric function, known as the critical points, were distinguished and modeled using standard analytic line shapes. The energy dependence of the critical points energies was thoroughly investigated as a function of Bi content and thin film strain. Critical points analysis in the Brillion zone showed that the top of the valence band is most strongly dependent on Bi content compared to other parts of the band structure. In addition, an interesting new critical point was observed that is attributed to alternative allowed optical transitions made possible by changes to the top of the valence band caused by resonant interactions with Bi orbitals. Several of the critical points were extrapolated to 100% Bi and showed reasonable agreement with the calculated band structure of GaBi. GaAs(1-x)Bi(x) (x= 03, 0.7 and 1.1%) based p+/n and n+/p heterostructure photovoltaic performance was characterized through IV and CV measurement. By introduction of Bi into GaAs, a non-zero EQE below the GaAs band edge energy was observed while the highest efficiency was obtained by ~ 0.7% Bi incorporation. EQE spectrum was modeled to find the minority carrier diffusion lengths of ~ Ln = 1600 and Lp = 140 nm for p-doped and n-doped GaAs92Bi08 in the doping profile of 10^15 - 10^16 cm^-3. Analysis of the CV measurement confirmed the background n-doping effect of Bi atom and the essential role of the cap layer to reduce multi-level recombination mechanisms at the cell edge to improve ideality factor. Low temperature grown GaAs was optimized to be used as photoconductive antenna in THz time-domain spectroscopy setup. The As content was investigated to optimize photo-carrier generation using 1550 nm laser excitation while maintaining high mobility and resistivity required for optical switching. A barrier layer of AlAs was added below the LT-GaAs to limit carrier diffusion into the GaAs substrate. Moreover, LT-GaAs layer thickness and post-growth annealing condition was optimized. The optimized structure (2-μm LT-GaAs on 60-nm AlAs, under As2:Ga BEP of ~7, annealed at 550°C for 1 minute) outperformed a commercial InGaAs antenna by a factor of 15 with 4.5 THz bandwidth and 75 dB signal-to-noise ratio at 1550 nm wavelength.
Author: Chih-Chun Wang
Author: Chih-Chun Wang
Author: Henry Kressel
Author: Christian Fuchs
Author: Yuh-Haw Wu
Author: Din-How Mei
Author: G.W. Cullen
Author: J. W. Matthews
Author: Lisa Parechanian Allen
Author: Mahsa Mahtab
Author: James Richard Shealy