Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Electronic Resource  (60)
  • 2005-2009  (6)
  • 1990-1994  (52)
  • 1960-1964  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Surface diffusion processes in molecular beam epitaxial growth of GaAs and AlAs as studied on GaAs (001)-(111)B facet structures (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 4138-4144 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Mechanisms of molecular beam epitaxy have been investigated for GaAs and AlAs by growing and analyzing the shapes of facet structures consisting of an (001) top surface and two (111)B side surfaces. It is found that all of the Ga flux on the three facet planes is incorporated into the film, but the growth rates on (111)B and (001) depend strongly on the As flux and are mainly determined by the diffusion of Ga ad-atoms between the two planes. In contrast, the diffusion of Al is found to be almost negligible, irrespective of the As flux. By analyzing the shape of the facet, the diffusion length, λ, of Ga on a (001) surface is estimated to be about 1 μm at 580 °C, while that of Al is about 0.02 μm. On (111)B, λ of Ga is found to be several μms. The reflectivity of diffusing Ga atoms is found to be far less than 1 for the (001)-(111)B boundary, and almost unity at facet boundaries where the (111)B side surfaces are bound by the (11¯0) side walls.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357364
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Characterization of Ga2Se3 at ZnSe/GaAs heterovalent interfaces (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 2788-2790 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Despite the valence difference across the junction, it has been shown that ZnSe/GaAs epilayer/epilayer interface state densities can be reduced to values comparable to the (Al,Ga)As/GaAs interface. We have previously reported a transmission electron microscopy study indicating that ZnSe/GaAs structures exhibiting low interface state densities are associated with the formation of an interfacial layer of zinc-blende Ga2Se3. In this letter we describe a procedure whereby an interfacial layer can be deliberately introduced prior to nucleation of ZnSe. In situ x-ray photoelectron spectroscopy is used to study the nature of the bonding at the interfacial layer. A comparison of the Se 3d core level features from the ZnSe epilayer surface, a Se-reacted GaAs surface, and from a separately grown Ga2Se3 epilayer, clearly indicates the same Se bonding characteristic for the Se-reacted interfacial layer and the Ga2Se3 epilayer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104762
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Characterization of GaAs grown on Si epitaxial layers on GaAs substrates (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 220-225 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: GaAs has been grown on 9 and 18 A(ring) thicknesses of epitaxial Si which was grown on GaAs (100) substrates. The GaAs on Si interface was characterized by cross-sectional transmission electron microscopy. A 9 A(ring) thickness of Si on GaAs is pseudomorphic while 18 A(ring) of Si is relaxed. Antiphase domains (APDs) were observed to annihilate near the GaAs on Si interface. Annihilation ocurred within 100 A(ring) of the interface for the 9 A(ring) thickness of Si and around 1500 A(ring) for the 18-A(ring) Si case. From a detailed analysis of the APD shapes and sizes, we deduce that GaGa bonds are energetically favored in the {111} planes and that two separate APD annihilation mechanisms occur. The growth mode of epitaxial Si on GaAs was also studied by in situ high-energy electron diffraction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347754
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Suppression and control of magnetic islands in toroidal plasmas (1991)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 3 (1991), S. 2285-2290 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Magnetic islands play an important role in determining the stability and confinement properties of toroidal plasmas. The nonlinear growth of magnetic islands can lead to major disruptions in tokamaks. In stellarators, which do not have a continuous symmetry, the formation of magnetic islands can set equilibrium beta limits. In the first part of this paper, a novel method is proposed for reducing drastically the size of m=2, n=1 islands in tokamaks by introducing a beamlet of energetic ions just outside the q=2 surface via parallel neutral-beam injection. A simple physical picture is given of the nonlinear stability of a tearing mode in the Rutherford regime in the presence of energetic ions. This physical picture is supported by a kinetic calculation in the long mean-free-path regime in which the effect of bootstrap currents and resistive interchanges are retained. Estimates show that the energy of the beamlet required for the suppression is a small fraction of that used for Ohmic or beam-heating of the background plasma. In the second part of the paper, an equilibrium beta limit is obtained for stellarators by calculating the island widths induced by finite plasma pressure; the widths are then constrained by the criterion of island overlap. The theory is applied to the Heliotron-E device [Nakamura et al., Phys. Fluids B 2, 2528 (1990)]. It is shown that some aspects of the experimental observations on internal disruptions in Heliotron-E can be interpreted as signatures of the equilibrium beta limit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.859595
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Near wakes of a circular cylinder in stratified flows (1990)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 2 (1990), S. 481-483 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Near wakes of a circular cylinder in linearly stratified flows are experimentally investigated by means of flow visualization and measurements of vortex shedding frequencies, at Reynolds numbers 5×103–104 and stratification parameters K smaller than 1.0. The study demonstrates that as K increases from zero, the vortex shedding from a circular cylinder is progressively strengthened, while the Strouhal number becomes gradually lower than that for a homogeneous flow. At a certain critical value of K, the enhanced vortex shedding is suddenly weakened and the Strouhal number increases sharply to a high value.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.857746
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Equilibrium beta limits in Heliotron-E due to magnetic island overlap (1990)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 2 (1990), S. 2528-2530 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Widths of magnetic islands induced by finite plasma pressure are computed for the Heliotron-E configuration [Phys. Rev. Lett. 53, 2242 (1984); Nucl. Fusion 27, 895 (1987)]. Equilibrium beta limits are obtained from the criterion of island overlap. Earlier experimental observations on internal disruptions in Heliotron-E are revisited.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.859375
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    An extreme ultraviolet radiation source for the simulation of the ionosphere (1991)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 62 (1991), S. 1721-1726 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An extreme ultraviolet (EUV) radiation source for space simulation of plasma and other related phenomena in the laboratory has been developed. A total of forty-eight small EUV lamps are put together to give a radiation diameter of more than 30 cm. The intensity of this lamp at the hydrogen Lyman-alpha line is more than twenty five times stronger than sunlight at the same wavelength and at a distance of about 30 cm from the source. The source is capable of emitting EUV radiations from 110 nm to the longer wavelengths, either continuously or in pulses, and has been used to produce a plasma of 105 els/cm3 when the pressure of NO gas in the chamber was 10−4 Torr. Since this plasma is extremely calm and fairly Maxwellian, it can be used to study the electron collection mechanism of a probe in a collision dominant medium. The source was also utilized to study the interaction between vibrationally excited nitrogen molecules and thermal electrons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1142412
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Molecular beam epitaxy and characterization of CdTe(211) and CdTe(133) films on GaAs(211)B substrates (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 1988-1990 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: CdTe films were grown in both the (211) and (133) orientations on GaAs(211)B substrates by molecular beam epitaxy. The orientation of the epitaxy is dependent on the thermal cleaning process. Studies of these films included in situ reflected high-energy electron diffraction, x-ray double-crystal diffractometry, transmission electron microscopy, and photoluminescence, which revealed high quality for both CdTe growth orientations, and especially for the CdTe(133). The lattice of the CdTe(211) growth tilts 3° with respect to its GaAs(211) substrate about the CdTe[01¯1]//GaAs[01¯1] coincidence axis. The CdTe(133) has no tilt with respect to its substrate, and its coincidence axes are CdTe[01¯1]//GaAs[01¯1] and CdTe[61¯1¯]//GaAs[1¯11].
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.105041
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Modulation of one-dimensional electron density in n-AlGaAs/GaAs edge quantum wire transistor (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 64 (1994), S. 2552-2554 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An array of AlGaAs/GaAs edge quantum wires (EQWIs) with an effective width of 80 nm was successfully prepared on a (111)B microfacet structure on a patterned substrate by molecular beam epitaxy. By forming a gate electrode on the wires, field effect transistor action has been successfully demonstrated. The conductance of the wire measured in magnetic fields has exhibited a clear Shubnikov–de Haas (SdH) oscillation, and its Landau plot shows a characteristic nonlinearity caused by the magnetic depopulation of one-dimensional (1D) subbands. It has been found that as the gate voltage decreases, the SdH peaks shift systematically toward lower magnetic fields, indicating a successful modulation of 1D electron density in the EQWI.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.111571
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Origin of dual epitaxy in the growth of CdTe on (2¯1¯1¯) GaAs (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1372-1374 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The atomic structure of the (1¯3¯3¯)CdTe/(2¯1¯1¯)GaAs interface is analyzed by high resolution transmission electron microscopy in order to elucidate the origin of the dual epitaxy in the growth of CdTe on (2¯1¯1¯)GaAs by molecular beam epitaxy. The analysis shows that the lattice mismatch at the interface is accommodated by a novel mechanism, which occurs with the combination of the 14.6% lattice mismatch between CdTe and GaAs and one wurtzite type bond sequence on the (2¯1¯1¯) substrate surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.107294
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...