ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • 1
    Electronic Resource
    Electronic Resource
    Dielectric response of strained and relaxed Si1−x−yGexCy alloys grown by molecular beam epitaxy on Si(001) (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 4578-4586 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Using spectroscopic ellipsometry, we measured the pseudodielectric function of Si1−x−yGexCy alloys (0≤x≤0.48,0≤y≤0.05) grown on Si(001) using molecular beam epitaxy. For pseudomorphically strained layers, the energy shifts of the E1, E1+Δ1, E0′, and E2 transitions are determined by line shape analysis and are due to alloy composition effects, as well as hydrostatic and shear strain. We developed expressions for hydrostatic and shear shift from continuum elasticity theory, using deformation potentials for Si and Ge, for biaxial stress parallel to the (001) growth plane in a diamond or zinc blende-type crystal and applied this to the ternary Si–Ge–C alloy. The energies of E1 and its spin-orbit split partner E1+Δ1 agree fairly well with theory. The E2 transitions in Si1−xGex at around 4.3 eV depend linearly on Ge concentration. In case of relaxed layers, the E1 and E1+Δ1 transitions are inhomogeneously broadened due to the influence of misfit and threading dislocations. For a silicon cap on top of a dislocated, relaxed SiGe layer, we recovered the bulk Si dielectric function. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363827
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Single-crystal Sn/Ge superlattices on Ge substrates: Growth and structural properties (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 875-877 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Short-period strained-layer α-Sn/Ge superlattices lattice matched to Ge(001) substrates have been synthesized for the first time. The thin, tetragonally distorted α-Sn layers are stabilized by a modified molecular beam epitaxy technique with large modulation of substrate temperature during growth. Optimization of growth conditions is achieved via in situ Auger electron spectroscopy and low-energy electron diffraction. This new kind of strained-layer superlattice is characterized by transmission electron microscopy, x-ray diffraction, and Raman scattering. Distinct superlattice effects are observed in the structural and phonon properties of the samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104264
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Annealing effects on carbon-induced germanium dots in silicon (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 72 (1998), S. 3344-3346 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The growth of 2.4 monolayers Ge on 0.2 monolayers of predeposited C on Si results in the formation of 15 nm size Ge islands. Fifty stacked layers of these C-induced Ge dots are grown on Si (001) at 460 °C. Different pieces of the wafer are annealed at temperatures between 460 and 950 °C and for times ranging from 1 to 20 min at 850 °C. For temperatures higher than 550 °C, a pronounced energy blueshift and an evolution from one broad photoluminescence peak to two well-resolved lines reflect a gradual transition from quantum dot states to quantum well-like states. As transmission electron microscopy images illustrate, diffusion processes completely smear out the sharp interfaces between the dots and the surrounding Si. An activation energy of only 1.6 eV and temperature-dependent diffusion coefficients are derived from simple model calculations. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.121598
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Structural and optical properties of vertically aligned InP quantum dots (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 2972-2974 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Stacked layers of self-assembled InP quantum dots embedded in Ga0.52In0.48P have been prepared by solid source molecular beam epitaxy. Thereby the distance between the dot layers has been varied from 2 to 16 nm. Cross sectional transmission electron microscopy shows that the InP dots are aligned in the growth direction [100]. As the distance between the dot layers is reduced, each dot of the first dot layer is reproduced in the upper layers, and this leads to an improvement of the dot size homogeneity of the stacked InP dot system. This is confirmed by photoluminescence (PL) measurements, which demonstrate a very narrow linewidth of 26 meV for a triple layer with 2 nm separation between the dot layers in comparison with a linewidth of 41 meV for a single layer sample. At the same time, the PL peak of the dots is shifted by 72 meV to lower energies which is ascribed to a reduced strain and strong electrical coupling between the densely stacked InP dots. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.120233
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Single-electron transistor as an electrometer measuring chemical potential variations (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 2514-2516 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic field dependence of the chemical potential of an electron system can be measured using a metallic single-electron transistor (SET). To demonstrate the method, a SET made of aluminum was fabricated on top of a GaAs/AlGaAs heterostructure containing a two-dimensional electron system (2DES). A change in the chemical potential of the 2DES causes a change in the contact voltage between the SET leads and the 2DES below the SET island which affects the current flow through the SET island. Tuning a voltage which is externally applied in series to the contact voltage, the change in the intrinsic contact voltage can be compensated to keep the SET current constant. With this tuning voltage, the change of the chemical potential by the magnetic field is directly measured. The method described here is applicable to other materials and other parameters affecting the intrinsic contact voltages. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.120104
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Formation of carbon-induced germanium dots (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 2340-2342 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A very small amount of pre-deposited C on a Si substrate causes island formation after epitaxial growth of less than 2 monolayers Ge. These C-induced Ge dots can be as small as 10 nm in lateral size and 1 nm in height. Their areal density is 1011 cm−2. Intense photoluminescence signal from these small Ge quantum dots is observed reaching a maximum for 2.1±0.3 monolayers of Ge. In the initial stages of island formation, the optical transition of the wetting layer is blue-shifted by strain compensation effects. We propose spatially indirect mechanisms of radiative recombination between electrons confined in the underlying wetting layer and holes confined in the Ge islands. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.120072
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Spatially indirect radiative recombination of carriers localized in Si1−x−yGexCy/Si1−yCy double quantum well structure on Si substrates (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 69 (1996), S. 1279-1281 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Closely spaced pseudomorphic Si1−x−yGexCy and Si1−yCy quantum well (QW) layers grown by solid-source molecular beam epitaxy on Si substrates are studied by photoluminescence (PL) spectroscopy at low temperature. In thin Si0.84Ge0.16/Si1−yCy double QWs, a no-phonon PL line of enhanced intensity and a weaker Si-like TO-phonon replica line are observed at lower energy, compared to reference structures with isolated Si0.84Ge0.16 and Si1−yCy QWs. These PL lines are attributed to spatially indirect (type II) transitions of electrons and holes confined to the coupled Si1−yCy and Si1−xGex layers, respectively. The PL intensity depends strongly on layer width. It increases exponentially for decreasing QW widths and it decreases when thin Si layers are deposited in between the QWs. This behavior is well described considering the wave function overlap of carriers which strongly influences the rate of indirect optical transitions. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.117391
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Time-resolved electroluminescence spectroscopy of resonant tunneling in GaAs-AlAs superlattices (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 2921-2923 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The carrier transport through a resonantly coupled GaAs-AlAs superlattice is investigated by time-resolved electroluminescence. Ultrashort current pulses are used to electrically inject electrons and holes into an externally biased superlattice. The time evolution of the emitted light is recorded, which allows us to directly monitor the temporal development of the carrier transport and the associated dynamics of the electric field. At resonance a strong reduction of the initial rise time of the electroluminescence signal is observed. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.116375
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Response to "Comment on ‘Nanoscale InP islands embedded in InGaP' '' [Appl. Phys. Lett. 67, 1166 (1995)] (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 1168-1169 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.114997
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Novel relaxation process in strained Si/Ge superlattices grown on Ge (001) (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1496-1498 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A new mode of misfit defect formation has been observed for the first time in high quality Si/Ge strained-layer superlattices grown by molecular beam epitaxy on Ge(001). In order to investigate the transition from coherent to incoherent growth we have studied a set of samples with a varying number of superlattice periods by transmission electron microscopy. High-resolution lattice imaging reveals that strain relaxation occurs through successive glide of 90° (a/6)〈211〉 Shockley partial dislocations on adjacent {111} planes. The resulting microtwins represent the only relaxation mechanism we observed in the samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.103375
    Location Call Number Expected 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...