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
    Possible evidence for quantum-size effects in self-assembled ultrathin films containing conjugated copolymers (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 3082-3088 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We present photoluminescence (PL), UV absorption, electroluminescence and x-ray reflectivity studies of self-assembled multilayer films containing alternate layers of conjugated copolymers, and nonconjugated insulating polymers. We show that the PL emission properties of these organic quantum wells can be "tuned'' by a proper choice of the conjugated copolymer and the thickness of the insulating layers. Particularly, some of the self-assembled ultrathin films containing thin (∼7 A(ring)) insulating polymeric layers exhibit a blue shift upon decreasing the thickness of the assembly. The PL shift is roughly proportional to 1/d2 where d is the thickness of the assembly, as expected for confined photogenerated electron-hole pair in an infinite square potential well. In contrast, the PL emission of similar assemblies but containing thick (∼40 A(ring)) insulating layers is independent of the assembly thickness and exhibit emission in the blue. This may suggest a strong spatial confinement. Light emitting diodes based on self-assembled multilayer films with improved efficiency and stability and with threshold voltage as low as 2.6 V could be fabricated. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.361250
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Mg implant activation and diffusion in GaAs during rapid thermal annealing in arsine ambient (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 67 (1990), S. 2857-2861 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Rapid thermal annealing of GaAs in an arsine ambient has been investigated. Uncapped 2-in. GaAs wafers were annealed in an arsine-N2 gas mixture up to annealing temperatures of 1100 °C and annealing times of 10 s. No surface decomposition occurred at an arsine partial pressure of 12.5 Torr. This capless annealing technique was employed to the activation of shallow Mg implants in GaAs. The sheet resistance of the annealed layers as a function of the annealing temperature reveals a minimum at approximately 930 °C. At higher temperatures diffusion of Mg becomes significant. A part of the Mg accumulates at the GaAs surface and diffuses out. The Mg loss due to outdiffusion can be reduced using Si3 N4 cap layers. The internal diffusion of Mg at high temperatures depends on the arsenic pressure during the annealing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.345456
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Abrupt Mg doping in thin graded base GaAs/GaAlAs heterojunction bipolar transistors (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 68 (1990), S. 1318-1323 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Abrupt Mg doping profiles have been realized in npn GaAs/GaAlAs heterojunction bipolar transistor (HBT) structures with compositional grading in the base region. The layers were grown by metalorganic vapor-phase epitaxy (MOVPE). Acceptor concentrations in the base are 1×1019 cm−3. Mg is also incorporated in the emitter and cap layers due to the Mg memory effect, and in the collector layer due to dopant diffusion. The incorporation of Mg is found to depend on the Si-donor concentration in these layers. Annealing experiments at 840 °C show only little broadening of the Mg doping profile. High-temperature process steps will consequently not change the Mg concentration significantly. We will demonstrate that neither the Mg memory effect nor Mg dopant diffusion limits the use of Mg for MOVPE-grown HBT layer sequences.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.346701
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    An ultrahigh-vacuum system for STM studies (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 2523-2526 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An ultrahigh-vacuum (UHV) system for STM studies is described where a home-built STM is combined with a novel facility for in situ exchange of samples and tips. Technical details concerning the design of the sample and tip holders and the manipulation and storage equipment are given. For the preparation of organic films a compact evaporation source comprising two ovens with an excellent thermal insulation was constructed. First STM results of a coronene film on graphite and of tungsten diselenide are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1144645
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Single-electron transistor fabricated by focused laser beam-induced doping of a GaAs/AlGaAs heterostructure (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 70 (1997), S. 2135-2137 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A single-electron transistor has been fabricated by an optical fabrication method. A small dot, a source and drain reservoir, and in-plane gates are all built from the two-dimensional electron gas of an n-type GaAs/AlGaAs heterostructure. Laser-written p-doped lines are used to define this dot with a diameter of about 70 nm and to insulate it from the in-plane gates. Tunnel junctions connect the dot with source and drain. The in-plane gates are used to tune the tunnel junctions and to change the electrostatic potential of the dot. A large charging energy of 5 meV and clear Coulomb-blockade oscillations are observed at helium temperature, due to a small dot capacitance of about 3×10−17 F. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.118969
    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...