Weak‐field magnetoresistance symmetry in epitaxial films and bulk crystals ofp‐type SnTe

ABSTRACTStructural and magnetic data are presented and discussed for epitaxial films of rare earth metals ( Dy, Ho, Er) on LaF3 films on the GaAs(TTT) surface and Fe on Ag films on the GaAs(001) surface. Both systems exhibit unusual structural characteristics which influence the magnetic properties of the metal films. In the case of rare earth epitaxy on LaF3 we present evidence for epitaxy across an incommensurate or discommensurate interface. Coherency strain is not transmitted into the metal which behaves much like bulk crystals of the rare earths. In the case of Fe films , tilted epitaxy and long-range coherency strain are confirmed by X-ray diffractometry. Methods of controlling some of these structural effects by modifying the epitaxial structures are presented.

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The Polarity of GaN: a Critical Review

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000831 ◽

1998 ◽

Vol 3 ◽

Cited By ~ 241

Author(s):

E. S. Hellman

Keyword(s):

Critical Review ◽

Polar Axis ◽

Epitaxial Films ◽

Wurtzite Structure ◽

Bulk Crystals ◽

Standard Framework

GaN, AlN and InGaN have a polar wurtzite structure and epitaxial films of these materials typically grow along the polar axis. Although the polarity of these nitrides has been studied by quite a number of techniques, many results in the literature are in conflict. In this paper an attempt is made to lay out a set of polarity assignments to provide a context for discussion of these results. A “standard framework” is proposed to correlate the disparate results, and the framework is used to draw general conclusions about the polarity of bulk crystals, VPE and MBE epitaxial films, and devices.

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Gkowth of YBa2Cu3O7-δ Single Crystals and Films by a Flux and a Sputtering Methods

MRS Proceedings ◽

10.1557/proc-99-647 ◽

1987 ◽

Vol 99 ◽

Author(s):

K. Takagi ◽

M. Hirao ◽

M. Hiratani ◽

H. Kakibayashi ◽

T. Aida ◽

...

Keyword(s):

Single Crystals ◽

High Resolution Electron Microscopy ◽

Growth Conditions ◽

Epitaxial Films ◽

Electric Resistivity ◽

Periodic Lattice ◽

Flux Growth ◽

Bulk Crystals ◽

Resolution Electron ◽

Diffusion Of Impurities

ABSTRACTYBa2Cu3O7-δ single crystals and epitaxial films are grown and characterized. In flux growth for bulk crystals, effects of growth conditions on yield and electric resistivity of crystals are examined. The yield of flaky crystals depends on the formation of cavities. The transition temperature is 86 K after annealing in an oxygen atmosphere. Films are prepared on SrTiO3 by sputtering and epitaxial growth is confirmed by high resolution electron microscopy. Periodic lattice defects are observed near the interface between the substrate and the film. It seems that these defects result from the diffusion of impurities from the substrate.

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Time dependent negative weak-field magnetoresistance in n-type lead telluride epitaxial films

phys stat sol (a) ◽

10.1002/pssa.2210470148 ◽

1978 ◽

Vol 47 (1) ◽

pp. K31-K34 ◽

Cited By ~ 3

Author(s):

C. Albers ◽

Ch. Walkowiak ◽

P. Schäfer ◽

I. Rechenberg

Keyword(s):

Lead Telluride ◽

Weak Field ◽

Epitaxial Films ◽

Time Dependent

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Epitaxial IV-VI Semiconductor Films

MRS Proceedings ◽

10.1557/proc-90-59 ◽

1986 ◽

Vol 90 ◽

Cited By ~ 1

Author(s):

T. K. Chu ◽

A. Martinez

Keyword(s):

Optical Transition ◽

Infrared Detector ◽

Optical Devices ◽

Epitaxial Films ◽

Small Scale ◽

Persistent Photoconductivity ◽

Semiconductor Films ◽

Bulk Crystals ◽

Detector Arrays ◽

Growth Method

ABSTRACTEpitaxial films of IV-VI semiconductors and their alloys form the basis of an infrared detector technology that offers advantages in material stability as well as spectral versatility. These films are prepared by epitaxial hot-wall techniques and their material properties are essentially the same as those of bulk crystals. Because of their stability, multilayer growths of the materials can be achieved in a straight-forward manner. To date, multi-color detectors and small scale two-color detector arrays have been demonstrated successfully. A brief review of the growth method and the growth characteristics is given. Recent advances in superlattice research, especially those of interest to electro-optical devices, will be discussed. These include persistent photoconductivity and sub-bandgap optical transition.

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Оптические и структурные свойства эпитаксиальных слоев Hg-=SUB=-0.7-=/SUB=-Cd-=SUB=-0.3-=/SUB=-Te

Физика и техника полупроводников ◽

10.21883/ftp.2021.11.51558.9689 ◽

2021 ◽

Vol 55 (11) ◽

pp. 1040

Author(s):

Д.А. Андрющенко ◽

М.С. Ружевич ◽

А.М. Смирнов ◽

Н.Л. Баженов ◽

К.Д. Мынбаев ◽

...

Keyword(s):

Solid Solution ◽

Optical Properties ◽

Diffraction Data ◽

Epitaxial Films ◽

Structural Quality ◽

Bulk Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Photoluminescence Studies

The results of comparative studies of the optical and structural properties of Hg0.7Cd0.3Te bulk crystals and epitaxial films grown by various methods are presented. The data of photoluminescence studies performed in the temperature range 4.2−300K showed the similarity of the optical properties of different samples and indicated a significant disordering of the solid solution. According to X-ray diffraction data, however, the scale of the disordering was not directly related to the structural quality of the material. The prospects for using the material grown by various methods in optoelectronics applications are discussed.

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Properties Of Homoepitaxially Mbe-Grown Gan

MRS Proceedings ◽

10.1557/proc-423-329 ◽

1996 ◽

Vol 423 ◽

Cited By ~ 2

Author(s):

T. Suski ◽

J. Krueger ◽

C. Kisielowski ◽

P. Phatak ◽

M. S. H. Leung ◽

...

Keyword(s):

Metalorganic Chemical Vapor Deposition ◽

Molecular Beam ◽

Chemical Vapor ◽

Epitaxial Films ◽

Chemical Vapor Deposition Method ◽

Bulk Crystals ◽

Acceptor Pair ◽

Dominant Band ◽

Bulk Single Crystals ◽

Donor Acceptor

AbstractBulk single crystals of GaN were used for epitaxial growth of GaN films by molecular beam epitaxy. Low temperature photoluminescence yields much higher intensity emission in the near bandedge region for epitaxial films with respect to the situation in bulk crystals. Character of this luminescence changes also. Dominant band-to-band transitions in the bulk crystals are exchanged by bound exciton and/or donor-acceptor pair transitions observed in the epitaxial layers. We will compare the obtained results with the available data on the homoepitaxial samples grown by metalorganic chemical vapor deposition method and discuss the importance of establishing the basic information on energetic positions of excitonic transitions in stress free samples.

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Weak-field magnetoresistance in noncubic (111)-oriented epitaxial films of n-type PbTe

Journal of Applied Physics ◽

10.1063/1.327884 ◽

1980 ◽

Vol 51 (4) ◽

pp. 2119 ◽

Cited By ~ 14

Author(s):

R. S. Allgaier ◽

J. B. Restorff ◽

Bland Houston ◽

J. D. Jensen ◽

A. Lopez-Otero

Keyword(s):

Weak Field ◽

Epitaxial Films

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Lattice imaging and pore structure of β ferric oxyhydroxide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108465 ◽

1978 ◽

Vol 36 (1) ◽

pp. 264-265

Author(s):

T. Baird ◽

J.R. Fryer ◽

S.T. Galbraith

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bulk Material ◽

Model Structure ◽

Bulk Crystals ◽

Lattice Imaging ◽

Thin Sections ◽

Ferric Oxyhydroxide ◽

Resolution Electron ◽

Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

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