Application of Channeling Techniques and High Resolution Transmission Electron Microscopy to Ion-Beam Damaged Zircon

1994 ◽  
Vol 373 ◽  
Author(s):  
N. Bordes ◽  
R.C. Ewing
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cross Sections ◽  
Radiation Effects ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Layer Depth ◽  
Damage Layer ◽  
Transmission Electron ◽  
Complementary Techniques

AbstractZircon (ZrSiO4) samples were irradiated at 100K with 400 keV Ar+ and Xe+ ion beams to fluences ranging from 5x1013 to 5x1015 ions/cm2. Rutherford backscattering spectroscopy (RBS) experiments were completed to study the dechanneling of He ions in the irradiated zircons. Cross-sections of some irradiated samples were prepared, and the zircon microstructure was examined by highresolution transmission electron microscopy (HRTEM). At doses greater than 8x1014 ions/cm2 or 0.8 dpa (displacements per atom), RBS channeling experiments showed the presence of a disordered or amorphous layer. The electron microscopy confirmed the presence of an amorphous layer extending over a depth of 300 to 350 nm (Ar+ irradiation) and 200 nm (Xe+ irradiation) in agreement with the damage layer depth calculated by TRIM. At depths extending beyond the damage peak, TEM reveals an amorphous layer with “islands” of crystalline material of σ 30 nm in size. These experiments show that RBS and TEM are complementary techniques in investigating radiation effects in irradiations of bulk ceramic.

Deformation under nanoindents in Si, Ge, and GaAs examined through transmission electron microscopy

2001 ◽  
Vol 16 (12) ◽  
pp. 3347-3350 ◽  
Author(s):  
S. J. Lloyd ◽  
J. M. Molina-Aldareguia ◽  
W. J. Clegg
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cross Sections ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Amorphous Material ◽  
Face Centered Cubic ◽  
Dislocation Generation ◽  
Transmission Electron ◽  
Face Centered

Cross sections through nanoindents on Si, Ge, and GaAs {001} were examined through transmission electron microscopy. A focused ion beam workstation was used to machine electron transparent windows through the indents. In both Si and Ge there was a transformed zone immediately under the indent composed of amorphous material and a mixture of face-centered-cubic and body-centered cubic crystals. Cracking and dislocation generation were also observed around the transformed zone. In GaAs the dominant deformation mechanism was twinning on the {11} planes. The hardness of these materials is discussed in light of these observations and their macroscopic material properties such as phase transformation pressure.

Mo-B-C and Ta-B-C Nanostructured Layers with Promising Fracture Toughness

2016 ◽  
Vol 368 ◽  
pp. 107-110 ◽  
Author(s):  
Jiří Buršík ◽  
Ivo Kuběna ◽  
Vilma Buršíková ◽  
Pavel Souček ◽  
Lukáš Zábranský ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Fracture Toughness ◽  
Transmission Electron Microscopy ◽  
Cross Sections ◽  
Fracture Resistance ◽  
Ion Beam ◽  
Transmission Electron ◽  
Focussed Ion Beam ◽  
Nanostructured Layers

X-B-C (X=Mo, Ta) layers prepared by magnetron sputtering were tested. Mechanical properties were characterized by means of nanoindentation experiments in both the static and the dynamic loading regime. The results were correlated with observations of the microstructure under indentation prints by means of scanning and transmission electron microscopy on cross sections prepared using a focussed ion beam. An excellent fracture resistance of prepared nanostructured coatings was found.

Self And Ion Beam Annealing of P,Ar, And Kr In Silicon

1985 ◽  
Vol 51 ◽  
Author(s):  
S. Cannavo ◽  
A. La Ferla ◽  
S.U. Campisano ◽  
E. Rimini ◽  
G. Ferla ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Current Density ◽  
Ion Beam ◽  
Amorphous Layer ◽  
High Current ◽  
Tem Analysis ◽  
Ion Channeling ◽  
Transmission Electron ◽  
Fluence Range

ABSTRACTThe damage produced by high current density ∿l0µA/cm2 implants of 120 keV P+ into <111> and <100> silicon wafers, 500 °m thick, has been investigated in the fluence range 1×l01 5/cm2-l×l016 /cm2 by ion channeling and by transmission electron microscopy. For both orientations the thickness of the damage layers increases with the fluence up to 2×1015 /cm2 and then decreases. The rate of regrowth is a factor two faster for the <100> with respect to the <111> oriented Si crystals. Similar ratios have been found in pre-amorphized samples and irradiated with Kr+ ions in the temperature range 350°C-430°C. The TEM analysis reveals the presence of hexagonal silicon and of twins in small amounts for both orientations. The beam induced epitaxial growth depends also on the species present in the amorphous layer. A comparison between self-annealing and beam annealing in Si <100> preamorphized with Ar+ or P+ shows a noticeable retardation of the growth rate in the presence of Ar+.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

Transmission Electron Microscopy of Evaporated Perylene Thin Films

1990 ◽  
Vol 48 (2) ◽  
pp. 336-337
Author(s):  
C. Ewins ◽  
J.R. Fryer
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Molecular Electronics ◽  
High Vacuum ◽  
Amorphous Layer ◽  
Electric Heater ◽  
Transmission Electron ◽  
Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

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