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
    Growth of carbon nanotubes by gas source molecular beam epitaxy (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 1973-1976 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Multiwall carbon nanotubes have been grown by gas source molecular beam epitaxy in the presence of Ni catalyst. Some nanotubes show thinner bases compared with their heads. First- and second-order Raman scattering spectra are used to study the structure of samples with different initial thicknesses of Ni layers. The second-order 2D Raman mode of carbon nanotubes shows a downshift compared with the graphite-like structure. The growth of carbon nanotubes is found to depend on the size of the metal droplets. When the initial Ni layer is either too thick or too thin, few carbon nanotubes are observed. The Raman spectra show graphite and glassy carbon structures for too thick and too thin initial Ni layer films, respectively. Only when a proper range of Ni catalyst film is used, carbon nanotubes could be found. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1337083
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ge/Si interdiffusion in the GeSi dots and wetting layers (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 90 (2001), S. 4290-4292 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The Ge/Si interdiffusion in GeSi dots grown on Si (001) substrate by gas-source molecular beam epitaxy is investigated. Transmission electron microscopy images show that, after annealing, the aspect ratio of the height to base diameter increases. Raman spectra show that the Si–Ge mode redshifts and the intensity of the local Si–Si mode increases with the increase of annealing temperature, which suggests the Ge/Si interdiffusion during annealing. The photoluminescence peaks from the dots and the wetting layers show blueshift due to the atomic intermixing during annealing. The interdiffusion thermal activation energies of GeSi dots and the wetting layers are 2.16 and 2.28 eV, respectively. The interdiffusion coefficient of the dots is about 40 times higher than that of wetting layers and the reasons were discussed. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1403667
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effective compliant substrate for low-dislocation relaxed SiGe growth (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 1219-1221 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An effective compliant substrate was fabricated for the growth of high-quality relaxed SiGe templates, by synthesizing a 20% B2O3 concentration borosilicate glass (BSG) in the silicon on insulator wafers. Substrates with 5%, 10%, and 20% B2O3 were used for 150 nm Si0.75Ge0.25 epitaxy. Double-axis x-ray diffraction measurements determined the relaxation and composition of the Si1−xGex layers. Cross-sectional transmission electron microscopy was used to observe the lattice of the SiGe epilayer and the Si substrate, dislocation density, and distribution. Raman spectroscopy was combined with step etch to study the samples. The strain sharing effect of the 20% BSG substrate was demonstrated. Thus, we concluded that this compliant substrate is a highly promising candidate for the growth of low-dislocation relaxed SiGe layers. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1351520
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Compliant effect of low-temperature Si buffer for SiGe growth (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 454-456 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Relaxed SiGe attracted much interest due to the applications for strained Si/SiGe high electron mobility transistor, metal-oxide-semiconductor field-effect transistor, heterojunction bipolar transistor, and other devices. High-quality relaxed SiGe templates, especially those with a low threading dislocation density and smooth surface, are critical for device performance. In this work, SiGe films on low-temperature Si buffer layers were grown by solid-source molecular-beam epitaxy and characterized by atomic force microscope, double-axis x-ray diffraction, and photoluminescence spectroscopy. It was demonstrated that, with the proper growth temperature and Si buffer thickness, the low-temperature Si buffer became tensily strained and reduced the lattice mismatch between the SiGe and the Si buffer layer. This performance is similar to that of the compliant substrate: a thin substrate that shares the mismatch strain in heteroepitaxy. Due to the smaller mismatch, misfit dislocation and threading dislocation densities were lower. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1337633
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Response to "Comment on ‘Optical and acoustic phonon modes in self-organized Ge quantum dot superlattices' " [Appl. Phys. Lett. 78, 1160 (2001)] (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 1162-1163 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1350590
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Effects of interdiffusion on the band alignment of GeSi dots (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 79 (2001), S. 1980-1982 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The interdiffusion effects on the band alignment of the GeSi dots embedded in Si matrix were studied by temperature- and excitation-power-dependent photoluminescence measurements. A different power-dependent behavior of the photoluminescence for the as-grown and the annealed samples was observed. It was suggested that the band alignments of the dots changed from type II to type I after annealing due to the Ge/Si interdiffusion. The decrease of the valence band offset, which was also induced by the Ge/Si interdiffusion, was observed from the temperature-dependent photoluminescence measurements. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1405152
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Optical and acoustic phonon modes in self-organized Ge quantum dot superlattices (2000)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 76 (2000), S. 586-588 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Raman scattering measurements were carried out in self-organized Ge quantum dot superlattices. The samples consisted of 25 periods of Ge quantum dots with different dot sizes sandwiched by 20 nm Si spacers, and were grown using solid-source molecular-beam epitaxy. Optical phonon modes were found to be around 300 cm−1, and a dependence of the Raman peak frequency on the size of dots was evidenced in good agreement with a prediction based on phonon confinement and strain effects. Acoustic phonons related to the Ge quantum dots have also been observed. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.125825
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Regimented placement of self-assembled Ge dots on selectively grown Si mesas (2000)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 76 (2000), S. 3591-3593 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The control of positioning of self-assembled dots is critical for the fabrication of regimented arrays in signal processing applications. We report the controllable positioning of self-assembled Ge dots using selectively grown Si mesas as a template. The dependence of the dot arrangement on growth temperature and Ge thickness has been investigated. The experimental results show ability to control the positioning of Ge dots based on energetically preferential nucleation. The Ge dot growth on Si mesas is demonstrated to be a promising way to realize the placement of regimented arrays of self-assembled dots and even a single dot. This technique can be extended to other heterostructure growths. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.126716
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Band alignments and photon-induced carrier transfer from wetting layers to Ge islands grown on Si(001) (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 1763-1765 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Temperature- and excitation-power-dependent photoluminescence measurements were carried out for the multilayer structure of Ge islands grown on a Si(001) substrate by gas-source molecular-beam epitaxy. When the excitation power increases from 10 to 400 mW, the photoluminescence peak from the Ge islands showed a large linear blueshift of 34 meV while that of the wetting layers did not change much. These two different power dependences are explained in terms of type-II and type-I band alignments for the islands and the wetting layers, respectively. When the sample temperature increased from 8 to 20 K, an anomalous increase of photoluminescence intensity for islands was accompanied by a rapid decrease of that from the wetting layers, implying that a large portion of photon-induced carriers in the wetting layer was transfered to the neighboring islands and the Si layer, respectively, thus resulting in an increase of photoluminescence intensity of the islands. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1356454
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Perfect alignment of self-organized Ge islands on pre-grown Si stripe mesas (2000)
    Springer
    Applied physics 70 (2000), S. 551-554 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 81.15Hi; 85.40Ux; 81.10Aj; 68.55Jk
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract. Self-organized Ge islands grown on patterned Si(001) substrates have been investigated. Selective epitaxial growth (SEG) of Si is carried out with gas-source molecular beam epitaxy to form Si stripe mesas followed by subsequent Ge island growth. Self-aligned Ge islands with regular spacing are formed on the 〈110〉-oriented ridges of the Si mesas. The regular spacing is driven by the repulsive interaction between the neighbor islands through the substrates. A mono-modal distribution of the islands has been observed on the ridges of the Si mesas. The spatial confinement as well as the preferential nucleation is believed to be the mechanism of this alignment of the self-organized Ge islands.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003390051078
    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...