Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 70 (1997), S. 1296-1298 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Phase images of 20–30-nm-diam silicon spheres were collected by holographic methods in a field-emission transmission electron microscope. The spherical geometry enables the effect of specimen thickness on the electron-wave phase to be separated from the intrinsic Si electron-optical refractive effects allowing a determination of the mean inner potential Φ0. This work finds Φ0=11.9±0.9 V characterizing amorphous Si and 12.1±1.3 V characterizing crystalline Si. The phase images can resolve a 2-nm-thick native oxide layer and give Φ0 for SiO2=10.1±0.6 V. The phase data can quickly recognize a surface layer, and the effect of a surface layer on the determination of the bulk mean potential can be minimized. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 517-521 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Time-resolved hot-stage transmission optical microscopy is used to characterize the nucleation and growth kinetics of amorphous GeTe thin-film crystallization. This technique provides experimental measurements of the fraction crystallized, the number of crystallites, and the crystallite size as a function of annealing time and temperature. The fraction-crystallized data are modelled using the Johnson–Mehl–Avrami formalism to give an Avrami exponent of 4, consistent with previous measurements via time-resolved reflection/transmission methods. Microstructural measurements provide sufficient data to deconvolute the individual contributions of nucleation and growth to this exponent. This work shows that crystallization of these films proceeds by nucleation at an increasing rate due to transient effects with isotropic two-dimensional growth in the film plane. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 331-333 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Crystallization is induced in amorphous 80 nm films of Ge48Te52 by electron irradiation to produce structures with characteristic dimensions as small as of 10–100 nm. The experiments are performed in a 200 keV field-emission scanning transmission electron microscope (TEM/STEM) that provides an electron probe about 1–2 nm in diameter (FWHM) with approximately 1 nA of current. When entire films are annealed in the absence of electron irradiation, they crystallize at approximately 450 K. Crystallization occurs under focused-probe electron irradiation when the average film temperature is as low as 300 K. The local transformation is driven by some combination of electron-beam heating and radiation-defect generation. A discussion is presented in the context of related nanocrystallization experiments driven by scanned-probe techniques for optical data storage applications. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Ultramicroscopy 52 (1993), S. 564-569 
    ISSN: 0304-3991
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Electrical Engineering, Measurement and Control Technology , Natural Sciences in General , Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a substantial improvement in the behavior of Josephson junctions scribed in Y1Ba2Cu3O7−δ films using a high-brightness field-emission electron gun source instead of a lower-brightness thermionic source. These junctions exhibit resistively shunted junction behavior over the entire temperature range from the coupling temperature to at least 4 K, a temperature window which can be larger than 55 K. Superconductor-normal-superconductor character is indicated by the exponential dependence of the critical current on temperature for all temperatures below 90 K. The data demonstrate that electron irradiation under these conditions produces a modified region which is completely normal above 4 K and is narrower in width than previously obtained. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background: Helicobacter pylori is strongly associated with peptic ulcer: H. pylori eradication markedly decreases the recurrence rate of duodenal and gastric ulcer, but the optimum length of antibiotic therapy in the eradication of H. pylori is still unclear. Aim: To verify the effectiveness and side-effect profile of an eradicating regimen consisting of omeprazole 20 mg daily for 4 weeks and, during the first week, combination antimicrobial treatment with tinidazole 500 mg b.d. plus clarithromycin 250 mg b.d. in patients with active duodenal and gastric ulcer. Methods: One hundred and ninety-six duodenal ulcer patients and 27 gastric ulcer patients with H. pylori infection were admitted into an open prospective study. Compliance was assessed by an accurate interview. Results: Overall, H. pylori was successfully eradicated in 201 of 223 patients (intention-to-treat 90.1%; 95% CI=85–94%): 176 of 196 duodenal ulcer patients became H. pylori-negative (89.8%; CI=85–94%) as well as 25 of 27 gastric ulcer patients (92.6%; CI=76–99%). Compliance was excellent in 221 of 223 (99.1%) patients evaluated as having taken all the medication as prescribed. Sixteen patients (7.2%) developed mild side effects during treatment. Conclusion: This combination treatment had excellent results with almost absolute compliance and a very low rate of minor side effects.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 4879-4885 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This work demonstrates the possibility of decreasing the C54–TiSi2 formation temperature during rapid thermal annealing (RTA) by more than 50 °C using a two-step binary Ti–Si codeposition process on Si (100) substrates. This process is based on codepositing a particular double-layer microstructure. The first layer is an amorphous Ti–Si alloy codeposited on Si (100) with a composition close to Ti5Si3. After crystallizing this first layer at temperatures near 600 °C, a second layer is formed by room-temperature codeposition of an amorphous capping layer with a composition close to TiSi2. Analyses by Rutherford backscattering spectrometry and film-thickness measurements by transmission electron microscopy on samples constructed according to this method show a structure of 20 nm TiSi1.3/45 nm Ti3.7Si3/Si. On rapid thermal annealing (3 °C/s to 710 °C), C49–TiSi2 formation occurs at the silicide/silicon interface keeping Ti5Si3 as an intermediate layer, and the capping layer is transformed to C54–TiSi2. This microstructure is fundamentally different from that developed after RTA of Ti/Si bilayers in which C49–TiSi2 forms and subsequently transforms to C54 at temperatures ∼800 °C. The two-step process studied here places hexagonal Ti5Si3 in close contact with the amorphous capping layer. This layer acts as a catalyst for the formation of C54–TiSi2 by decreasing the energy barrier for C54 nucleation. The present experiments also suggest that the transformation from C49 to C54 can be mediated by a layer of Ti5Si3 in much the same fashion as metal-mediated crystallization processes. The enhanced formation of C54–TiSi2 using the two-step silicidation of binary Ti–Si alloys is an attractive alternative to other methods which lower the C54 formation temperature by introducing a third element. Such a third element can produce thermodynamically stable high-resistivity silicides that may decrease device performance. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 2272-2282 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Measurements of the temperature and time dependence of visible diode laser transmission and reflection are combined with transmission electron microscopy (TEM) to study the crystallization of two 75 nm Ge-Te thin films. Near-stoichiometric Ge48Te52 transforms by the rapid growth of crystals through the film thickness followed by 2D growth in the film plane. Changes in film reflection and transmission are directly related to the volume fraction transformed. The optical measurements are interpreted in terms of classical Johnson–Mehl–Avrami kinetics. A Kissinger analysis gives an activation energy for crystallization of 1.7 eV. Isothermal measurements lead to an Avrami exponent of 4.5. The data are modeled using a numerical temperature-dependent expression developed by Greer [Acta Metall. 30, 171 (1982)]. Off-stoichiometric Ge54Te46 films show markedly different crystallization behavior. Transmission and reflection measurements indicate that the transformation proceeds by rapid growth of a crystalline layer at the free surface of the film followed by 1D growth of this layer through the film. The observation is confirmed by TEM imaging and diffraction. This work shows that reflection and transmission measurements can be an effective method for the study of crystallization kinetics of amorphous thin films, particularly when more traditional calorimetric methods cannot be employed.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...