Helium-induced porous layer formation in Silicon.

1987 ◽  
Vol 107 ◽  
Author(s):  
A. Van Veen ◽  
C.C. Griffioen ◽  
J.H. Evans
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Porous Layer ◽  
Low Dose ◽  
Layer Formation ◽  
Helium Bubbles ◽  
Transmission Electron ◽  
Helium Implantation ◽  
The Stability

AbstractThe annealing behaviour of helium bubbles formed by ambient temperature 10 keV helium implantation into silicon has been studied using transmission electron microscopy (TEM) and helium desorption spectroscopy (HDS). Although the TEM results indicated conventional bubble annealing processes due to bubble migration and coalescence, the HDS data demonstrated that helium can permeate out of bubbles in silicon around 1000K to leave behind empty cavities, thus giving a porous layer coincident with the original helium implant profile.The addition of a low dose of implanted oxygen to the silicon-helium samples has been shown to strongly improve the stability of the porous layer, at least up to 1300K.

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

Plasticity and Microstructure of Irradiated Pd

1998 ◽  
Vol 540 ◽  
Author(s):  
N. Baluc ◽  
Y. Dai ◽  
M. Victoria
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Plastic Deformation ◽  
Ambient Temperature ◽  
Tensile Deformation ◽  
Microscopic Level ◽  
Macroscopic Scale ◽  
Slip Bands ◽  
Transmission Electron ◽  
Mev Protons

AbstractSingle crystalline specimens of pure Pd have been irradiated at ambient temperature with 590 MeV protons to doses ranging between 10−4 and 10−1 dpa. Tensile deformation experiments revealed that irradiation induces hardening and embrittlement, while scanning (SEM) and transmission electron microscopy (TEM) observations showed that plastic deformation of specimens irradiated to a dose ≥ 10−2 dpa is strongly localized and yields the creation of slip bands at the macroscopic scale and of defect-free channels at the microscopic level.

Characterization, Optical and Impedance Study of ZnSe Nanostructure

2013 ◽  
Vol 699 ◽  
pp. 490-495
Author(s):  
Ramna Tripathi ◽  
Akhilesh Kumar
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Impedance Spectroscopy ◽  
Zinc Selenide ◽  
Relaxation Times ◽  
Complex Impedance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
The Stability

Zinc selenide nanoparticle has been synthesized using soft chemical routes. The particles were capped using 2-mercaptoethanol to achieve the stability and avoid the coalescence. The as-obtained particles were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), UV–VIS absorption and photoluminescence (PL) spectra. The impedance studies were carried out as a function of frequency (100 Hz–1 MHz) and temperature (298–373 K) by impedance spectroscopy. An analysis of the complex impedance (z' and z") with frequency is performed assuming a distribution of relaxation times.

scholarly journals Getting the Most out of Direct Detection Cameras for Low-Dose Transmission Electron Microscopy

2014 ◽  
Vol 20 (S3) ◽  
pp. 2140-2141
Author(s):  
Anchi Cheng ◽  
James Pulokas ◽  
Sargis Dallakyan ◽  
Amber Herold ◽  
Clinton S. Potter ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Low Dose ◽  
Direct Detection ◽  
Transmission Electron

A Transmission Electron Microscopy Study of the Effect of Interfaces on Bubble Formation in He-Implanted Cu-Nb Multilayers

2012 ◽  
Vol 18 (1) ◽  
pp. 152-161 ◽  
Author(s):  
D. Bhattacharyya ◽  
M.J. Demkowicz ◽  
Y.-Q. Wang ◽  
R.E. Baumer ◽  
M. Nastasi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Layer Thickness ◽  
Bubble Diameter ◽  
Bubble Formation ◽  
Nuclear Reaction Analysis ◽  
Cross Sectional ◽  
Helium Bubbles ◽  
Transmission Electron ◽  
Pure Cu

AbstractMagnetron sputtered thin films of Cu, Nb, and Cu-Nb multilayers with 2.5 and 5 nm nominal layer thickness were deposited on Si and implanted with 4He+ and 3He+ ions. Secondary ion mass spectroscopy and nuclear reaction analysis, respectively, were used to measure the 4He+ and 3He+ concentration profile with depth inside the films. Cross-sectional transmission electron microscopy was used to characterize the helium bubbles. Analysis of the contrast from helium bubbles in defocused transmission electron microscope images showed a minimum bubble diameter of 1.25 nm. While pure Cu and Nb films showed bubble contrast over the entire range of helium implantation, the multilayers exhibited bubbles only above a critical He concentration that increased almost linearly with decreasing layer thickness. The work shows that large amounts of helium can be trapped at incoherent interfaces in the form of stable, nanometer-size bubbles.

scholarly journals Interlayer Microstructure Analysis of the Transition Zone in the Silicon/Perovskite Tandem Solar Cell

Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6819
Author(s):  
Grażyna Kulesza-Matlak ◽  
Kazimierz Drabczyk ◽  
Anna Sypień ◽  
Agnieszka Pająk ◽  
Łukasz Major ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Solar Cell ◽  
Transition Zone ◽  
Porous Layer ◽  
Perovskite Layer ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Highly Porous ◽  
Made In

The aim of the paper was to determine the morphology of the layers and the microstructure of the transition zone present in the proposed tandem solar structure. The bottom-silicon solar cell plays a double role: first as a highly porous non-reflecting material, and second as a scaffold for top-perovskite cell. In the presented solution, the use of a porous layer made of (e.g., TiO2) is excluded in favor of chemically etched wires on the silicon surface. The porous layer of silicon consists of nano- and microwires etched with metal assisted etching (MAE). The perovskite layer is introduced by a two-step chemical method into the spaces between the wires to fully fill them and intentionally form an additional capping layer at the same time. To examine the structure made in this way, advanced microscopic methods were used including scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM), also in high resolution.

The Oxidation Stability of Boron Nitride Thin Films on MgO and TiO2 Substrates

1991 ◽  
Vol 250 ◽  
Author(s):  
Xiaomei Qiu ◽  
Abhaya K. Datye ◽  
Robert T. Paine ◽  
Lawrence. F. Allard
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Oxidation Stability ◽  
Film Coating ◽  
Thin Film Coating ◽  
Film Coatings ◽  
Thin Film Coatings ◽  
Transmission Electron ◽  
The Stability

AbstractThe stability of BN thin film coatings (2–5 nm thick) on MgO and TiO2 substrates was investigated using transmission electron microscopy (TEM). The samples were heated in air for at least 16 hours at temperatures ranging from 773 K - 1273 K. On MgO supports, the BN thin film coating was lost by 1073 K due to a solid state reaction with the substrate leading to formation of Mg2B2O5. No such reaction occurred with the TiO2 substrate and the BN was stable even at 1273 K. However, the coating appeared to ball up and phase segregate into islands of near-graphitic BN and clumps of TiO2 (rutile). The oxidizing treatment appears to promote the transformation from turbostratic BN to graphitic BN.

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