The apparent effect of sample surface damage on the dielectric parameters of GaAs

2007 ◽  
Vol 401-402 ◽  
pp. 238-241 ◽  
Author(s):  
J.A.A. Engelbrecht ◽  
N.G. Hashe ◽  
K.T. Hillie ◽  
C.H. Claassens
Keyword(s):  
Surface Damage ◽  
Sample Surface ◽  
Apparent Effect ◽  
Dielectric Parameters

Localized Epoxy Layer Formation on Surface Defect Using a Micro-Brush in a Plucking System

2009 ◽  
Author(s):  
Kun-Lin Lin ◽  
Jian-Shing Luo ◽  
Hsiu-Ting Lee ◽  
Jeremy D. Russell
Keyword(s):  
Surface Defect ◽  
Surface Damage ◽  
Sample Surface ◽  
Dark Field ◽  
Layer Formation ◽  
X Ray ◽  
Transmission Electron ◽  
Annular Dark Field ◽  
Glass Needle ◽  
Novel Method

Abstract This paper provides details of a novel method developed to cover a tiny epoxy layer as an intermediate buffer on the site-specific surface defect using a micro-bush on the tip of a glass needle in a plucking system without sample surface damage and localization problems. It describes the method and some real cases. The microstructures are investigated using an FEI Tecnai TF20 field emission gun transmission electron microscopy equipped with a high angle annular dark field detector, an energy dispersive X-ray spectroscopy, and Gatan image filter systems. The paper explains the micro-brushes and buffer layer preparation though figures and illustrations.

Transmission Electron Microscopy Nano Beam Diffraction Sensitivity Study in Focused Ion Beam Prepared Semiconductor Test Structures

2017 ◽  
Author(s):  
James Demarest
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Strain Analysis ◽  
Surface Damage ◽  
Sample Surface ◽  
Sensitivity Study ◽  
Image Resolution ◽  
Advanced Technology ◽  
Step Size ◽  
Transmission Electron

Abstract In this paper, a sample was made on an advanced technology node finFET test structure and analyzed in a 200kV TEM equipped with a 4k camera and commercially available strain analysis software using a sub 5nm parallel probe. It was observed that doubling the step size of the data acquisition from 5nm per step to 2.5nm per step with a 4k image resolution changed the sensitivity of the data by about 4%. However, increasing the number of pixels of each diffraction pattern from 2k to 4k and removing the focused ion beam prepared sample surface damage both showed greater than 10% improvements in nano beam electron diffraction (NBD) sensitivity greater than 10%. As a result, it is possible to obtain greater sensitivity of the NBD technique by employing these changes in response to the evolving characterization needs.

scholarly journals Angular Dependence of Copper Surface Damage Induced by an Intense Coherent THz Radiation Beam

2020 ◽  
Vol 5 (1) ◽  
pp. 16
Author(s):  
Salvatore Macis ◽  
Luca Tomarchio ◽  
Silvia Tofani ◽  
S. Javad Rezvani ◽  
Luigi Faillace ◽  
...  
Keyword(s):  
Electric Field ◽  
Incidence Angle ◽  
Normal Incidence ◽  
Surface Damage ◽  
Sample Surface ◽  
Copper Surface ◽  
Metallic Surface ◽  
Thz Radiation ◽  
Particle Accelerators ◽  
Radiation Beam

In this work, we show the damage induced by an intense coherent terahertz (THz) beam on copper surfaces. The metallic surface was irradiated by multiple picosecond THz pulses generated by the Free Electron Laser (FEL) at the ISIR facility of the Osaka University, reaching an electric field on the sample surface up to ~4 GV/m. No damage occurs at normal incidence, while images and spectroscopic analysis of the surface point out a clear dependence of the damage on the incidence angle, the electric field intensity, and polarization of the pulsed THz radiation. Ab initio analysis shows that the damage at high incidence angles could be related to the increase of the absorbance, i.e., to the increase of the temperature around or above 1000 °C. The experimental approach we introduced with multiple fast irradiations represents a new powerful technique useful to test, in a reproducible way, the damage induced by an intense electric gradient on copper and other metallic surfaces in view of future THz-based compact particle accelerators.

Pulsed Microwave Irradiation of Graphite/Epoxy Composites

1988 ◽  
Vol 124 ◽  
Author(s):  
R. B. James ◽  
P. R. Bolton ◽  
R. A. Alvarez
Keyword(s):  
Light Emission ◽  
Electrical Breakdown ◽  
Surface Region ◽  
Surface Damage ◽  
Sample Surface ◽  
Optical Measurements ◽  
Time Resolved ◽  
Near Surface ◽  
Reflected Power ◽  
Surface Decomposition

ABSTRACTWe have measured the microwave-induced damage to the near-surface region of a graphite/epoxy composite material for 1.1-μs pulses at a frequency of 2.856 GHz and a pulse power of up to 8 MW. Rectangular samples were irradiated by single-pass TE10 traveling wave pulses inside a WR-284 waveguide, and in situ and post irradiation studies were performed to characterize the material modifications induced by the microwave pulses. The results of the time-resolved optical measurements in vacuo show that surface decomposition of the epoxy resin occurs for incident pulse powers exceeding 1.1 MW, and that the surface damage is accompanied by a large increase in the reflected microwave power. Simultaneous with the onset of surface decomposition, significant light emission from the sample and a large enhancement of the gas pressure in the test cell were observed. The large increments in both the reflected power and light emission are attributed to the formation of a plasma due to electrical breakdown of the gas at (or near) the sample surface.

Electron-Backscatter Diffraction of Photovoltaic Thin Films

2007 ◽  
Vol 1012 ◽  
Author(s):  
Helio Moutinho ◽  
Ramesh Dhere ◽  
Chun-Sheng Jiang ◽  
Bobby To ◽  
Mowafak Al-Jassim
Keyword(s):  
Electron Backscatter Diffraction ◽  
Ion Beam ◽  
Surface Damage ◽  
Sample Surface ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Backscatter Diffraction

AbstractIn electron-backscatter diffraction, crystalline orientation maps are formed while the electron beam of an SEM scans the sample surface. EBSD requires a flat sample to avoid shadowing of the electrons from the detector by surface features. In this work, we investigate the preparation of CdTe samples deposited by close-spaced sublimation for EBSD analysis. Untreated samples were rough, resulting in areas with no EBSD signal. We processed the samples by polishing and ion-beam milling. Polishing produced flat samples, but low-quality EBDS data, because the top surface of the samples had poor crystallinity. In contrast, ion-beam milling proved to be suitable for producing flat samples with minimal surface damage, yielding good EBSD data. We also analyzed the samples with atomic force microscopy, and correlated the quality of the EBSD data with sample roughness. The EBSD data showed that the CdTe films were randomly oriented and had columnar growth and a high density of <111> twin boundaries.

scholarly journals Coating based on basalt protection metal structures

Tehnika ◽  
2021 ◽  
Vol 76 (3) ◽  
pp. 302-307
Author(s):  
Marko Pavlović ◽  
Marina Dojčinović ◽  
Ljubiša Andrić ◽  
Dragan Radulović ◽  
Ljiljana Trumbulović
Keyword(s):  
Protective Coatings ◽  
Surface Damage ◽  
Sample Surface ◽  
Small Mass ◽  
Test Results ◽  
Organic Additives ◽  
Refractory Coating ◽  
Metal Structures ◽  
Basalt Rock ◽  
Morphology Of Surface

The paper present the results of the synthesis of a new refractory coating based on basalt for the protection of metal construction under conditions of cavitation. Initial basalt samples obtained from the locality Vrelo - Kopaonik. The basalt based refractory filler was obtained by crushing and grinding selected samples of basalt rock. XRD, SEM and optical microscopy methods were used to characterize the obtained filler samples. The research defined the composition of basalt -based coating with epoxy resinbased binder, organic additives and organic solvent. The resistance properties of protective coatings applied to metal surface were investigated using the ultrasonic vibration method with a stationary sample according to the ASTM G 32 standard. To evaluate the resistance of the sample surface to the action of cavitation, the sample surface was examined before and during testing. The surface of the samples was monitored by scanning electron microscopy in order to analyze the morphology of surface damage. Computer image analysis according to the Image Pro Plus program was applied to assess the damage to the sample surface. The obtained test results showed high resistance of the coating layers to the effect of cavitation, with small mass losses, small damage to the coating surface and a cavitation rate of 0,1 mg/min.

Surface Structure in Microtomed Sections Caused by Glass and Diamond Knives

1971 ◽  
Vol 29 ◽  
pp. 456-457
Author(s):  
J. Temple Black ◽  
William G. Boldosser
Keyword(s):  
Plastic Deformation ◽  
Epoxy Resin ◽  
Carbon Coating ◽  
Surface Damage ◽  
Body Angle ◽  
Normal Manner ◽  
Bottom Side ◽  
Cutting Direction ◽  
Made In ◽  
Diamond Knife

Ultramicrotomy produces plastic deformation in the surfaces of microtomed TEM specimens which can not generally be observed unless special preparations are made. In this study, a typical biological composite of tissue (infundibular thoracic attachment) infiltrated in the normal manner with an embedding epoxy resin (Epon 812 in a 60/40 mixture) was microtomed with glass and diamond knives, both with 45 degree body angle. Sectioning was done in Portor Blum Mt-2 and Mt-1 microtomes. Sections were collected on formvar coated grids so that both the top side and the bottom side of the sections could be examined. Sections were then placed in a vacuum evaporator and self-shadowed with carbon. Some were chromium shadowed at a 30 degree angle. The sections were then examined in a Phillips 300 TEM at 60kv.Carbon coating (C) or carbon coating with chrom shadowing (C-Ch) makes in effect, single stage replicas of the surfaces of the sections and thus allows the damage in the surfaces to be observable in the TEM. Figure 1 (see key to figures) shows the bottom side of a diamond knife section, carbon self-shadowed and chrom shadowed perpendicular to the cutting direction. Very fine knife marks and surface damage can be observed.

Field ion microscopy

1988 ◽  
Vol 46 ◽  
pp. 434-435
Author(s):  
Gert Ehrlich
Keyword(s):  
Low Temperature ◽  
Sample Surface ◽  
Low Pressure ◽  
Radius Of Curvature ◽  
Field Ion Microscopy ◽  
Phosphor Screen ◽  
Ion Microscopy ◽  
Field Ion Microscope

The field ion microscope, devised by Erwin Muller in the 1950's, was the first instrument to depict the structure of surfaces in atomic detail. An FIM image of a (111) plane of tungsten (Fig.l) is typical of what can be done by this microscope: for this small plane, every atom, at a separation of 4.48Å from its neighbors in the plane, is revealed. The image of the plane is highly enlarged, as it is projected on a phosphor screen with a radius of curvature more than a million times that of the sample. Müller achieved the resolution necessary to reveal individual atoms by imaging with ions, accommodated to the object at a low temperature. The ions are created at the sample surface by ionization of an inert image gas (usually helium), present at a low pressure (< 1 mTorr). at fields on the order of 4V/Å.

A technique to prepare cross-sectional TEM specimens of semiconducting devices

1986 ◽  
Vol 44 ◽  
pp. 742-743
Author(s):  
A. K. Rai ◽  
P. P. Pronko
Keyword(s):  
Thin Films ◽  
Surface Region ◽  
Sample Surface ◽  
Specific Region ◽  
Cross Sectional ◽  
Thin Sections ◽  
The Past ◽  
Device Structures ◽  
Ion Implanted

Several techniques have been reported in the past to prepare cross(x)-sectional TEM specimen. These methods are applicable when the sample surface is uniform. Examples of samples having uniform surfaces are ion implanted samples, thin films deposited on substrates and epilayers grown on substrates. Once device structures are fabricated on the surfaces of appropriate materials these surfaces will no longer remain uniform. For samples with uniform surfaces it does not matter which part of the surface region remains in the thin sections of the x-sectional TEM specimen since it is similar everywhere. However, in order to study a specific region of a device employing x-sectional TEM, one has to make sure that the desired region is thinned. In the present work a simple way to obtain thin sections of desired device region is described.

The Basic Physical Principles of Ion, Electron, and X-Ray Detectors and Their Application to Microanalysis

1985 ◽  
Vol 43 ◽  
pp. 154-157
Author(s):  
A.J. Tousimis
Keyword(s):  
Ion Beam ◽  
Depth Resolution ◽  
Sample Surface ◽  
High Energy ◽  
X Rays ◽  
X Ray ◽  
Electrons And Ions ◽  
Spatial Depth ◽  
Minimum Surface Area ◽  
Physical Principles

An integral and of prime importance of any microtopography and microanalysis instrument system is its electron, x-ray and ion detector(s). The resolution and sensitivity of the electron microscope (TEM, SEM, STEM) and microanalyzers (SIMS and electron probe x-ray microanalyzers) are closely related to those of the sensing and recording devices incorporated with them.Table I lists characteristic sensitivities, minimum surface area and depth analyzed by various methods. Smaller ion, electron and x-ray beam diameters than those listed, are possible with currently available electromagnetic or electrostatic columns. Therefore, improvements in sensitivity and spatial/depth resolution of microanalysis will follow that of the detectors. In most of these methods, the sample surface is subjected to a stationary, line or raster scanning photon, electron or ion beam. The resultant radiation: photons (low energy) or high energy (x-rays), electrons and ions are detected and analyzed.

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