GaN Single Crystalline Domain Growth on Graphene Substrate

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

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Superstructures and ordering phenomena in ceramic superconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166014 ◽

1996 ◽

Vol 54 ◽

pp. 710-711

Author(s):

R. Gronsky

Keyword(s):

Domain Growth ◽

Small Displacement ◽

Small Scale ◽

Ceramic Superconductors ◽

Oxygen Sublattices ◽

Tweed Contrast ◽

Diffraction Patterns ◽

Representative Image ◽

Static Lattice ◽

Modulation Wavelength

It is now well established that the phase transformation behavior of YBa2Cu3O6+δ is significantly influenced by matrix strain effects, as evidenced by the formation of accommodation twins, the occurrence of diffuse scattering in diffraction patterns, the appearance of tweed contrast in electron micrographs, and the generation of displacive modulation superstructures, all of which have been successfully modeled via simple Monte Carlo simulations. The model is based upon a static lattice formulation with two types of excitations, one of which is a change in oxygen occupancy, and the other a small displacement of both the copper and oxygen sublattices. Results of these simulations show that a displacive superstructure forms very rapidly in a morphology of finely textured domains, followed by domain growth and a more sharply defined modulation wavelength, ultimately evolving into a strong <110> tweed with 5 nm to 7 nm period. What is new about these findings is the revelation that both the small-scale deformation superstructures and coarser tweed morphologies can result from displacive modulations in ordered YBa2Cu3O6+δ and need not be restricted to domain coarsening of the disordered phase. Figures 1 and 2 show a representative image and diffraction pattern for fully-ordered (δ = 1) YBa2Cu3O6+δ associated with a long-period <110> modulation.

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Recombination Characteristics of Single-Crystalline Silicon Wafers with a Damaged Near-Surface Layer

Ukrainian Journal of Physics ◽

10.15407/ujpe58.02.0142 ◽

2013 ◽

Vol 58 (2) ◽

pp. 142-150 ◽

Cited By ~ 1

Author(s):

A.V. Sachenko ◽

◽

V.P. Kostylev ◽

V.G. Litovchenko ◽

V.G. Popov ◽

...

Keyword(s):

Surface Layer ◽

Crystalline Silicon ◽

Silicon Wafers ◽

Single Crystalline Silicon ◽

Near Surface ◽

Single Crystalline

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Synthesis of Jumbo-size Single Crystalline Bi$lt;inf$gt;2$lt;/inf$gt;Se$lt;inf$gt;3$lt;/inf$gt; Nanoplates and Nanoribbons by Vapor Transportation

Journal of Inorganic Materials ◽

10.15541/jim20140087 ◽

2014 ◽

Vol 29 (11) ◽

pp. 1199

Author(s):

LI Xiao-Shuai ◽

WANG Zeng-Mei ◽

ZHU Ming-Fang ◽

WANG Shan-Peng ◽

TAO Xu-Tang ◽

...

Keyword(s):

Single Crystalline

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Formation of Large, Orientation-Controlled, Nearly Single Crystalline Si Thin Films on SiO2 Using Contact Printing of Rolled and Annealed Nickel Tapes

MRS Proceedings ◽

10.1557/proc-762-a17.13 ◽

2003 ◽

Vol 762 ◽

Author(s):

Hwang Huh ◽

Jung H. Shin

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

High Resolution ◽

Amorphous Silicon ◽

Tem Analysis ◽

Contact Printing ◽

Single Crystalline ◽

High Resolution Tem ◽

Lateral Crystallization ◽

Si Films

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)

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