The Influence of Angstrom-Scale Roughness on the Laser-Induced Damage Threshold of Single-Crystal ZnGeP2

Magnetorheological processing was applied to polish the working surfaces of single-crystal ZnGeP2, in which a non-aqueous liquid with the magnetic particles of carbonyl iron with the addition of nanodiamonds was used. Samples of a single-crystal ZnGeP2 with an Angstrom level of surface roughness were received. The use of magnetorheological polish allowed the more accurate characterization of the possible structural defects that emerged on the surface of a single crystal and had a size of ~0.5–1.5 μm. The laser-induced damage threshold (LIDT) value at the indicated orders of magnitude of the surface roughness parameters was determined not by the quality of polishing, but by the number of point depressions caused by the physical limitations of the structural configuration of the crystal volume. These results are in good agreement with the assumption made about a significant effect of the concentration of dislocations in a ZnGeP2 crystal on LIDT.

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The Influence of the Angstrom-scale Roughness on the Laser-induced Damage Threshold of the ZnGeP2 Single Crystal

10.20944/preprints202111.0563.v1 ◽

2021 ◽

Author(s):

Nikolai Yudin ◽

Andrey Khudoley ◽

Mikhail Zinoviev ◽

Sergey Podzvalov ◽

Elena Slyunko ◽

...

Keyword(s):

Surface Roughness ◽

Single Crystal ◽

Magnetic Particles ◽

Damage Threshold ◽

Structural Defects ◽

Physical Limitations ◽

Laser Induced Damage ◽

Crystal Volume ◽

Scale Roughness

Magnetorheological processing was applied to polish the working surfaces of the ZnGeP2 single crystal, in which a non-aqueous liquid with magnetic particles of carbonyl iron with the addition of nanodiamonds was used. Samples of a single crystal ZnGeP2 with an angstrom level of surface roughness were received. the use of MRP has allowed more accurately characterizing possible structural defects that have emerged on the surface of a single crystal and have a size of ~ 0.5-1.5 μm. the LIDT value at the indicated or-ders of magnitude of the surface roughness parameters is determined not by the quality of polishing, but by the number of point depressions caused by physical limitations of the structural configuration of the crystal volume. These results are in good agreement with the assumption made about a significant effect of the concentration of dislocations in a ZnGeP2 crystal on LIDT.

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Impact of Structural Defects on the Surface Quality of Hardwood Species Sliced Veneers

Applied Sciences ◽

10.3390/app10186265 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6265

Author(s):

Vasiliki Kamperidou ◽

Efstratios Aidinidis ◽

Ioannis Barboutis

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Wood Species ◽

Research Work ◽

Structural Defects ◽

Material Surface ◽

Typical Structure ◽

Hardwood Species ◽

The Impact

The surface roughness constitutes one of the most critical properties of wood and wood veneers for their extended utilization, affecting the bonding ability of the veneers with one another in the manufacturing of wood composites, the finishing, coating and preservation processes, and the appearance and texture of the material surface. In this research work, logs of five significant European hardwood species (oak, chestnut, ash, poplar, cherry) of Balkan origin were sliced into decorative veneers. Their surface roughness was examined by applying a stylus tracing method, on typical wood structure areas of each wood species, as well as around the areas of wood defects (knots, decay, annual rings irregularities, etc.), to compare them and assess the impact of the defects on the surface quality of veneers. The chestnut veneers presented the smoothest surfaces, while ash veneers, despite the higher density, recorded the highest roughness. In most of the cases, the roughness was found to be significantly lower around the defects, compared to the typical structure surfaces, probably due to lower porosity, higher density and the presence of tensile wood. The results reveal that the presence of defects does not affect the roughness of the veneers and increases neither the processing requirements of the veneer sheets before finishing, nor the respective production cost of veneers and the veneer-based wood panels. The high utilization prospects of the examined wood species in veneer production, even those bearing various defects, is highlighted.

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Investigation on the SR method growth, etching, birefringence, laser damage threshold and thermal characterization of strontium bis (hydrogen l-malate) hexahydrate single crystal

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2014.01.022 ◽

2014 ◽

Vol 401 ◽

pp. 200-204 ◽

Cited By ~ 22

Author(s):

A. Senthil ◽

P. Ramasamy

Keyword(s):

Single Crystal ◽

Damage Threshold ◽

Thermal Characterization ◽

Laser Damage Threshold ◽

Laser Damage ◽

Sr Method

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Growth and Characterization of Single Crystal Epitaxial CoGa on MBE Grown III-V Semiconductors

MRS Proceedings ◽

10.1557/proc-144-613 ◽

1988 ◽

Vol 144 ◽

Author(s):

K. C. Garrison ◽

C. J. Palmstrøm ◽

R. A. Bartynski

Keyword(s):

Substrate Temperature ◽

Single Crystal ◽

Single Crystals ◽

Structural Quality ◽

High Quality ◽

Auger Analysis ◽

Post Deposition

ABSTRACTWe have demonstrated growth of high quality single crystal CoGa films on Ga1−xAlxAs. These films were fabricated in-situ by codeposition of Co and Ga on MBE grown Ga1−xAlxAs(100) surfaces. The elemental composition of the films was determined using Rutherford Backscattering (RBS) and in-situ Auger analysis. The structural quality of the films' surfaces was studied using RHEED (during deposition) and LEED (post deposition). RBS channeling was used to determine the bulk crystalline quality of these films.For ∼500 Å CoGa films grown at ∼450°C substrate temperature, channeling data showed good quality epitaxial single crystals [χmin ∼7%] with minimal dechanneling at the interface.

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Fabrication and Characterization of Single-Crystal Diamond Membranes for Quantum Photonics with Tunable Microcavities

Micromachines ◽

10.3390/mi11121080 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1080

Author(s):

Julia Heupel ◽

Maximilian Pallmann ◽

Jonathan Körber ◽

Rolf Merz ◽

Michael Kopnarski ◽

...

Keyword(s):

Surface Roughness ◽

Single Crystal ◽

Membrane Thickness ◽

Initial Surface ◽

Crucial Component ◽

Single Crystal Diamond ◽

Fabrication And Characterization ◽

Etching Parameters ◽

Quantum Photonics

The development of quantum technologies is one of the big challenges in modern research. A crucial component for many applications is an efficient, coherent spin–photon interface, and coupling single-color centers in thin diamond membranes to a microcavity is a promising approach. To structure such micrometer thin single-crystal diamond (SCD) membranes with a good quality, it is important to minimize defects originating from polishing or etching procedures. Here, we report on the fabrication of SCD membranes, with various diameters, exhibiting a low surface roughness down to 0.4 nm on a small area scale, by etching through a diamond bulk mask with angled holes. A significant reduction in pits induced by micromasking and polishing damages was accomplished by the application of alternating Ar/Cl2 + O2 dry etching steps. By a variation of etching parameters regarding the Ar/Cl2 step, an enhanced planarization of the surface was obtained, in particular, for surfaces with a higher initial surface roughness of several nanometers. Furthermore, we present the successful bonding of an SCD membrane via van der Waals forces on a cavity mirror and perform finesse measurements which yielded values between 500 and 5000, depending on the position and hence on the membrane thickness. Our results are promising for, e.g., an efficient spin–photon interface.

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Ultra-thin films for plasmonics: a technology overview

Nanotechnology Reviews ◽

10.1515/ntrev-2015-0021 ◽

2015 ◽

Vol 4 (3) ◽

Cited By ~ 28

Author(s):

Radu Malureanu ◽

Andrei Lavrinenko

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Support Surface ◽

New Materials ◽

Infra Red ◽

Plasmon Polaritons ◽

Plasmon Propagation ◽

Made In

AbstractUltra-thin films with low surface roughness that support surface plasmon-polaritons in the infra-red and visible ranges are needed in order to improve the performance of devices based on the manipulation of plasmon propagation. Increasing amount of efforts is made in order not only to improve the quality of the deposited layers but also to diminish their thickness and to find new materials that could be used in this field. In this review, we consider various thin films used in the field of plasmonics and metamaterials in the visible and IR range. We focus our presentation on technological issues of their deposition and reported characterization of film plasmonic performance.

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Optical and Electrical Properties of Cd Te Laser-Synthetized

MRS Proceedings ◽

10.1557/proc-13-665 ◽

1982 ◽

Vol 13 ◽

Cited By ~ 3

Author(s):

L. Baufay ◽

A. Pigeolet ◽

R. Andrew ◽

L.D. Laude

Keyword(s):

Electrical Properties ◽

Single Crystal ◽

Electrical Characterization ◽

Point Of View ◽

Optical And Electrical Properties ◽

Impurity States ◽

Absorption Measurements ◽

Forbidden Gap

ABSTRACTOptical and electrical characterization of CdTe synthetized by laser irradiationofamultilayer film of alternately Cd and Te is achieved. Optical absorption measurements evidence the good quality of these films and show that they have behaviour comparable to the single crystal. The influence of the irradiation conditions on the electrical properties of such CdTe films is discussed; they are compared to single crystal from the point of view of resistivity. It is shown that it is possible to prepare by this means samples devoid of impurity states in the middle of the forbidden gap. Finally, the ohmicity of Au, Al, Cr, ITO and non irradiated Cd/Te sandwich contacts is tested.

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Growth, crystalline perfection, optical, thermal, laser damage threshold and electrical characterization of melaminium levulinate monohydrate single crystal

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2015.05.025 ◽

2015 ◽

Vol 426 ◽

pp. 86-94 ◽

Cited By ~ 7

Author(s):

N. Sivakumar ◽

N. Kanagathara ◽

G. Bhagavannarayana ◽

S. Kalainathan ◽

G. Anbalagan

Keyword(s):

Single Crystal ◽

Electrical Characterization ◽

Damage Threshold ◽

Laser Damage Threshold ◽

Laser Damage ◽

Crystalline Perfection

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Nondestructive Characterization of GaN Films Grown at Low and High Temperatures

MRS Proceedings ◽

10.1557/proc-591-313 ◽

1999 ◽

Vol 591 ◽

Author(s):

C.H. Yana ◽

H.W. Yao ◽

J.M. Van Hove ◽

A.M. Wowchak ◽

P.P. Chow ◽

...

Keyword(s):

Surface Roughness ◽

High Temperatures ◽

Sapphire Substrates ◽

Wurtzite Crystal Structure ◽

Phonon Spectra ◽

Scattering Geometry ◽

Back Scattering ◽

Nondestructive Characterization

ABSTRACTGaN films grown on GaAs and sapphire substrates by molecular beam epitaxy (MBE) and metalorganic vapor phase epitaxy (MOVPE) at both low and high temperatures (LT and HT) were characterized by Raman scattering and variable angle spectroscopic ellipsometry (VASE). Optical phonon spectra of GaN films are obtained through back-scattering geometry. Crystal quality of these films was qualitatively examined using phonon line-width. Phonon spectra showed that the HT GaN has wurtzite crystal structure, while LT GaN and GaN/GaAs have cubic-like structures. Thickness nonuniformity and defect-related absorption can be characterized by pseudo dielectric functions directly. Surface roughness also can be determined by using an effective-medium approximation (EMA) over-layer in a VASE analysis. Anisotropic optical constants of GaN, both ordinary and extraordinary, were obtained in the spectral range of 0.75 to 6.5 eV with the consideration of surface roughness, through the small and large angles of incidence, respectively. The film thickness of the GaN was accurately determined via the analysis as well.

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