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
    Capacitance properties in n-type AlxGa1−xAs (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 55 (1989), S. 2414-2416 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The electrical properties of n-type AlxGa1−x As, for x〉0.2, are governed by deep donor states (formerly called DX centers) created by the isolated donor atoms. We have studied the capacitance properties of such layers for Si and Sn dopants. The meanings of the capacitance-voltage carrier profiling and of the capacitance dependence with temperature have been considered. The deep donor energy position with respect to the Γ minimum has been determined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.102031
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    AlxGa1−xN:Si Schottky barrier photodiodes with fast response and high detectivity (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 73 (1998), S. 2146-2148 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Gold and nickel Schottky barrier photovoltaic detectors have been fabricated on Si-doped AlxGa1−xN layers (0≤x≤0.22) grown on sapphire by metalorganic vapor phase epitaxy. Responsivity is independent of the Schottky metal or diode size, and also of the incident power in the range measured (10 mW/m2–2 kW/m2). A higher visible rejection has been observed in the spectral response of Au photodiodes (〉103). Time response is resistance-capacitance limited, with time constants as short as 14 ns in Al0.22Ga0.78N diodes. Low frequency noise studies are also presented, and detectivities of 6.1×107 and 1.2×107 mHz1/2 W−1 are determined in GaN/Au and Al0.22Ga0.78N/Au detectors, at −2 V bias. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.122405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Electron capture by DX centers in AlGaAs and related compounds (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 55 (1989), S. 1732-1734 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: n-type dopants in Alx Ga1−x As, GaAs1−x Px, and related compounds create deep donors that control the free-electron concentration for x〉0.2. The electron capture by the deep donors shows a very nonexponential dependence with filling time. In this letter the electron capture kinetics is modeled, and the influence of the donor ionization factor, sample degeneracy, and size effects, are introduced. Capture barrier energy determination is discussed, and a comparison with experimental capture data is made.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.102202
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Influence of refilling effects on deep-level transient spectroscopy measurements in Se-doped AlxGa1−xAs (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 72 (1992), S. 525-530 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Deep-level transient spectroscopy (DLTS) and constant-capacitance DLTS (CC-DLTS) techniques have been used to investigate selenium-related DX centers in AlGaAs alloys. The value of the thermal activation energy obtained by both techniques was the same (0.21 eV); however, experimental curves show some important differences. While CC-DLTS curves show only one peak, which reveals that there exists only one DX center in Se-doped AlGaAs, in DLTS curves it is possible to resolve up to two peaks lying at a lower temperature than the one observed by CC-DLTS. This disagreement may be due to the fact that DLTS measurements are strongly affected by refilling effects which occur in the edge zone of the space-charge region during capacitance transients performed at constant voltage. These effects accelerate the capacitance transients and can lead to too high thermal-emission rates. In contrast, these effects do not affect CC-DLTS curves, because in constant-capacitance voltage transients the edge of the space-charge region remains unchanged and refilling effects do not take place. These effects are rather important on DX levels because they exhibit thermally activated capture cross sections and very low ionization factors at the experimental temperatures and, therefore, capture processes are slow and their time constants can be similar to those of the emission processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.351883
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Study of the optical properties of fused quartz after a sequential implantation with Si and Au ions (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 73 (1998), S. 1574-1576 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Implantation of Au ions into Si-implanted fused quartz strongly enhances the photoluminescence (PL) intensity around 630 nm measured after subsequent sample annealing at 900 °C. This effect is attributed to the enhancement of the formation of Si nanocrystals by the presence of Au ions and not by ion-implantation-induced defects. This conclusion was deduced by monitoring the defect formation in fused silica by 2 MeV Si ion implantation with doses ranging from 2×1016 to 1×1017 Si/cm2. Some of the 4×1016 Si/cm2-implanted samples were reimplanted at a similar depth with 10 MeV Au ions at doses of 4×1016 and 1.2×1017 Au/cm2. The absorption spectroscopy, electron paramagnetic resonance and PL measurements show the presence of B2 and E′ matrix point defects in as-prepared Si-implanted samples. As these defects disappear after annealing at 600 °C, the presence of a strong PL peak in samples implanted and annealed at 900 °C strongly suggests that the observed luminescence is produced by Si nanoparticle formation. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.122208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Dependence on the In concentration of the piezoelectric field in (111)B InGaAs/GaAs strained heterostructures (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 65 (1994), S. 2042-2044 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A series of (111)B InxGa1−xAs/GaAs multiple quantum well p-i-n structures have been investigated via low temperature photocurrent and photoluminescence spectroscopies. The indium mole fraction was in the range of 0.07–0.23. Evolution of the experimental blueshifts of the transition energies, with the external bias, agreed very well with the theoretical calculations. This allowed us to obtain precise information about the piezoelectric constant, e14, for the various In compositions. For the range of x investigated, we have found e14(x) to be linear with x but significantly lower than predicted by a simple linear interpolation of the accepted values for GaAs and InAs. © 1994 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.112787
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Influence of delta-doping profile and interface roughness on the transport properties of pseudomorphic heterostructures (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 64 (1994), S. 907-909 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thickness effects of the InGaAs channel on photoluminescence and transport properties of δ-doped Al0.3Ga0.7As/In0.3Ga0.7As heterostructures are investigated. The spreading of the Si δ-doping layer is deduced from a comparison of the measured charge with self-consistent calculations assuming a Gaussian Si distribution profile and a definite ionization probability of the Si-related DX centers. With decreasing channel thickness below 80 A(ring), the effect of the spreading on the sheet carrier concentration increases and the low temperature mobility decreases due to roughness scattering at the In0.3Ga0.7As/GaAs interface. In channels thicker than 80 A(ring) the thickness-independent alloy scattering process dominates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.110992
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Per-carrier nonlinear optical response of [111]-oriented piezoelectric InGaAs/GaAs multiple quantum wells (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 417-423 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We measure the per-carrier nonlinear responses caused by photoexcited carriers in two strained [111]-oriented InGaAs/GaAs multiple-quantum-well structures, and we compare them to that measured in a [100]-oriented structure. Without an external bias, we find that the absorption coefficient changes per photogenerated carrier for the [111]-oriented piezoelectric materials are smaller than for the [100]-oriented materials, not larger, as originally suggested. Subsequently, measurements of the per-carrier nonlinear responses as a function of reverse bias voltage demonstrate that the smaller per-carrier nonlinearities measured for the [111] structures are partially the result of a broadening of the excitons by the huge in-well fields, but can be primarily attributed to the quality of the [111]-grown materials. When corrected for differing in-well fields and for differing excitonic linewidths, the per-carrier responses are similar in magnitude, suggesting that the [111] response may eventually approach that of [100] material, but probably will not significantly exceed it. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360846
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    A Raman spectroscopic study of the Si, Be, and C incorporation in InxGa1−xAs relaxed layers (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 78 (1995), S. 4690-4695 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The incorporation of high concentrations ((approximately-greater-than)1019 cm−3) of Si, Be, and C in InxGa1−xAs relaxed layers has been studied as a function of In content (x≤0.16) by Raman spectroscopy of local vibrational modes (LVM). The frequencies of the Raman peaks resulting from the convolution of several split modes shift to lower values as the In content is increased, the carbon acceptor (CAs) local mode frequency showing the strongest dependency on x. Features attributed exclusively to the influence of In on second-neighbor sites are identified only in the Si-doped samples. The transverse and longitudinal modes expected from the splitting of a LVM of CAs with one In first neighbor are not observed in layers with x up to 0.085. A new calibration for the BeGa, CAs, and Si-related LVM leads to the conclusion that In increases the total electrical activation of Si and favors its incorporation on group-III sublattice sites. In contrast, no influence of In on the Be or C doping activation has been detected. The analysis of the CAs LVM spectra supports the view that in InxGa1−xAs CAs is preferably surrounded by Ga instead of In atoms for x≤0.085. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.359816
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Room- and low-temperature assessment of pseudomorphic AlGaAs/InGaAs/GaAs high-electron-mobility transistor structures by photoluminescence spectroscopy (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 5931-5944 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The use of room- and low-temperature photoluminescence (PL) spectroscopy for the assessment of n-type pseudomorphic AlGaAs/InGaAs/GaAs high-electron-mobility transistor structures is reported. We describe a method to determine the InAs mole fraction x, the channel layer thickness L, and the confined two-dimensional electron gas density (ns), based on the comparison between the PL transitions and the recombination energies derived from self-consistent calculations of the subband structure. A detailed analysis of the optical transitions and their dependence on the Fermi level position and temperature is performed. It is shown that, in real devices, the high sensitivity of the recombination energies and intensities on small changes of the parameters x, L, and ns allows us to detect deviations from their nominal structural parameters within the uncertainty of the molecular beam epitaxy growth technique. The present assessment procedure has been applied to a significant number of samples, and it has been backed by independent measurements of these parameters by more sophisticated techniques such as Shubnikov–de Haas and PL excitation in standard and gated samples, and by physical techniques like transmission electron microscopy and Auger spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358416
    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...