BKD in the SEM: Toward a smaller information volume

1994 ◽  
Vol 52 ◽  
pp. 606-607 ◽  
Author(s):  
K. Troost ◽  
J.-D. Kamminga
Keyword(s):  
Texture Analysis ◽  
Beam Current ◽  
Electron Gun ◽  
Lateral Resolution ◽  
Bulk Materials ◽  
Interaction Volume ◽  
Fine Grained ◽  
Information Depth ◽  
Lower Beam ◽  
Optical Brightness

Upto now, the recording of backscatter Kikuchi diffraction (BKD) patterns (also called electron backscattering patterns, EBSP) for microscale texture analysis is mostly performed at high primary beam voltages U > 20 kV using an SEM with a tungsten or LaB6 electron gun. Under these circumstances, a lateral resolution of 0.2-0.5 μm has been reported. However, the texture analysis of fine-grained bulk materials or vacuum-deposited thin metallic layers as used in the IC-industry requires a higher spatial resolution. A fieldemission electron gun (FEG) with a much higher electron-optical brightness can deliver the 1-nA beam current needed for EBSP recording in a spot of about 10 nm, enabling a lateral resolution of 20×80 nm3 and an information depth of 10 nm at 20 kV. In Ref. 2, the possibility of using lower beam voltages to obtain an even higher resolution is mentioned. Monte Carlo simulations indeed show that the interaction volume decreases at least linearly with decreasing U.

Study on Electron Beam Welding of AZ61 Magnesium Alloy

2010 ◽  
Vol 34-35 ◽  
pp. 1516-1520
Author(s):  
Hong Ye ◽  
Han Li Yang ◽  
Zhong Lin Yan
Keyword(s):  
Electron Beam ◽  
Magnesium Alloys ◽  
Welding Speed ◽  
Electron Beam Welding ◽  
Weld Zone ◽  
Welding Process ◽  
Processing Parameters ◽  
Beam Current ◽  
Fine Grained ◽  
Section Shape

Electron beam welding process of AZ61 with 10mm thickness magnesium alloys was investigated. The influence of processing parameters including focusing current, welding beam current and welding speed was researched. The results show that an ideal weld bead can be formed by choosing processing parameters properly. Focusing current is main parameter that determines cross section shape. The beam current and welding speed are main parameters that determine the weld width and dimensions. The test results for typical welds indicate that the microhardness of the weld zone is better than that of the base meta1. A fine-grained weld region has been observed and no obvious heat-affected zone is found. The fusion zone mainly consists of small α-Mg phase and β-Mg17A112. The small grains and β phases in the joint are believed to play an important role in the increase of the strength of weld for AZ61 magnesium alloys.

Texture Analysis with Area Detectors

2005 ◽  
Vol 105 ◽  
pp. 71-76 ◽  
Author(s):  
Kurt Helming ◽  
Uwe Preckwinkel
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Data Sets ◽  
Angle Of Incidence ◽  
Surface Layers ◽  
Area Detector ◽  
Texture Information ◽  
Pole Figures ◽  
Information Depth

Starting from simple geometric considerations concerning directions and orientations, intelligent strategies for pole figure measurements were developed for the area detector. The amount and quality of texture information contained in measured or available data sets can be directly controlled. The texture approximation is done by the component method. The method does not have any restrictions concerning the grids of sample directions in the pole figures. An almost constant information depth can be obtained at a low angle of incidence of the primary beam for the study of thin surface layers.

Preparation of fine-grained MgO and Gd2O3 stabilized ZrO2 thin films by electron beam physical vapor deposition co-evaporation

1997 ◽  
Vol 12 (12) ◽  
pp. 3260-3265 ◽  
Author(s):  
F. Tcheliebou ◽  
M. Boulouz ◽  
A. Boyer
Keyword(s):  
Thin Films ◽  
Electron Beam ◽  
Average Particle Size ◽  
Electron Gun ◽  
Cubic Phase ◽  
Crystallographic Structure ◽  
Average Particle ◽  
Scanning Electron Micrographs ◽  
Dopant Content ◽  
Fine Grained

Thin films of ZrO2 doped with MgO and Gd2O3, 1–1.5 μm in thickness are formed onto nickel substrates by reactive thermal evaporation using a dual-hearth electron gun. X-ray diffraction patterns of the deposits show changes in the crystallographic structure and average particle size as a function of the dopant content. A mixture of monoclinic and tetragonal phases gradually disappears to become a single cubic phase with increasing dopant molar fraction. The average crystallite size deduced from diffraction line broadening decreases as the dopant content increases. This observation is strongly confirmed by scanning electron micrographs which reveal a smooth surface topography. Fine-grained materials obtained here are interpreted in terms of high nucleation rate and kinetically limited grain growth. It appears that composition, crystallographic structure, and microstructure relations are of paramount importance in ZrO2-based films prepared by electron-beam evaporation.

The role of surface characteristics in low-voltage SEM of polymers

1991 ◽  
Vol 49 ◽  
pp. 1034-1035
Author(s):  
S J. Krause ◽  
W.W. Adams
Keyword(s):  
Low Voltage ◽  
Surface Characteristics ◽  
Beam Current ◽  
Image Features ◽  
Coating Process ◽  
Voltage Imaging ◽  
Interaction Volume ◽  
Beam Interaction ◽  
Beam Damage

It has been shown that there are numerous advantages in imaging both coated and uncoated polymers in scanning electron microscopy (SEM) at low voltages (LV) from 0.5 to 2.0 keV compared to imaging at conventional voltages of 10 to 20 keV. In imaging metal coated polymers in LVSEM beam damage is reduced, contrast is improved, and charging from irregularly shaped features is reduced or eliminated. Imaging uncoated polymers in LVSEM allows observation of the surface with little or no charging and with no alterations of surface features from the metal coating process required for higher voltage imaging. This is particularly important for high resolution studies where it is desired to image features 1 to 10 nm in size. At low voltages the sample-beam interaction volume resides closer to the surface which increases the ratio or exiting current to that of the primary beam current.

Tantalum replicas of freeze-fractured proteoliposomes

1986 ◽  
Vol 44 ◽  
pp. 56-57
Author(s):  
M.J. Costello ◽  
F. Burgess ◽  
J. Escaig
Keyword(s):  
High Resolution ◽  
Carbon Deposition ◽  
Freeze Fracture ◽  
Metal Films ◽  
Electron Gun ◽  
Intramembrane Particles ◽  
Fine Grained ◽  
Tantalum Metal ◽  
Pure Tantalum

Tantalum will form thin, fine-grained metal films, and under some conditions, continuous films with high resolution. We have prepared pure tantalum metal replicas of frozen fractured proteoliposomes employing a new electron gun designed for the Reichert Cryofract 190 freeze-fracture-etch device. The replicas are similar in appearance to those made with conventional platinum/carbon deposition except that tantalum replicas can be made thinner and with smaller grains, and the intramembrane particles (IMPs) which occur on fracture faces have smaller dimensions.

Investigation of the throughput of the dosing device gas leak for gas discharge electron gun

2012 ◽  
Vol 16 (5) ◽  
pp. 25-30
Author(s):  
I.V. Mel'nik ◽  
S.B. Tugaj
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Glow Discharge ◽  
High Voltage ◽  
Beam Current ◽  
Electron Gun ◽  
Technological Equipment ◽  
Gas Leak ◽  
Electron Guns ◽  
Empirical Coefficients

Model of capacity of valve with conic rod, which is used for control of beam current of high voltage glow discharge electron guns, is considered. Because of complicity of valve details geometry, mathematical model of dozed item is improved by suitable choosing of empirical coefficients and its approximation. On the base of modeling and experimental data analyzing of dependence of valve exploitation characteristics from geometry parameters of dozed item is provided. Obtained results can be used for simulation of stability of operation of high voltage glow discharge electron guns inconsisting of technological equipment

Texture analysis of fine-grained stainless steel by SEM/EBSD

2017 ◽  
Vol 2017.23 (0) ◽  
pp. 902
Author(s):  
Kyoichi ISHIDA ◽  
Ritsu HIROHARA ◽  
Muneyuki IMAFUKU
Keyword(s):  
Stainless Steel ◽  
Texture Analysis ◽  
Fine Grained

Investigation on Fabricating High Aspect Ratio Microholes on Silicon by FIB/SEM Milling

2012 ◽  
Vol 626 ◽  
pp. 436-439
Author(s):  
Fatin Syazana Jamaludin ◽  
Mohd Faizul Mohd Sabri
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Dwell Time ◽  
Milling Time ◽  
Gas Injection ◽  
Beam Current ◽  
Milling Process ◽  
Injection System ◽  
Lower Beam ◽  
Beam Currents

The aspect ratio of microholes milled on silicon by FIB/SEM milling was investigated with various beam currents and initial depths of mill. Lower beam current gives finer surface and more accurate structure. The results showed that the highest depth of microhole fabricated using FIB/SEM milling was 17.45µm, and maximum aspect ratio 1:8, without using gas injection system (GIS). The value of depth obtained was less than the initial depth of mill due to re-deposition, influenced by low sputter yield of silicon. Milling time and dwell time play important roles in milling process to get high aspect ratio of microholes.

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