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
  • 1
    Electronic Resource
    Electronic Resource
    Determination of tilted superlattice structure by atomic force microscopy (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 55 (1989), S. 2491-2493 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have analyzed the structure of tilted superlattices on atomically stepped surfaces by using atomic force microscopy to detect ridges of GaAs formed by the selective oxidation and removal of intervening AlAs regions. Oxides were removed in a liquid cell of the atomic force microscope while scanning. We have demonstrated plan views which reveal the superlattice length and width uniformity, but the method is also in principle suited for cross-sectional samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.102008
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Accurate multiple-quantum-well growth using real-time optical flux monitoring (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 65 (1994), S. 4-6 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a real-time molecular beam epitaxy control system based on optical flux monitoring (OFM) that is capable of producing thin AlAs/GaAs layers of accurate thickness. We demonstrate the system's ability to detect and compensate for growth rate variations by growing AlAs/GaAs multi-quantum-well structures while deliberately ramping the GaAs growth rate to simulate a severe effusion cell instability. Results show that a sample grown under these conditions without OFM control (i.e., while using conventional timed shutter control) exhibited multiple photoluminescence peaks, indicating that its quantum wells differed in thickness, while a sample grown using OFM shutter control exhibited a single narrow peak, indicating that its quantum wells were nearly identical in width. Analysis of the OFM shutter control sample's photoluminescence linewidth shows that the resulting quantum-well thickness variation were less than 1%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.113070
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Terrace width evolution during step-flow growth with multiterrace adatom migration (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 7351-7357 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have developed a computer-solvable model of step-flow growth that includes both anisotropic multiterrace adatom migration and asymmetric step edge attachment. We find that terrace widths equalize not only when each adatom preferentially attaches to the ascending step edge of the terrace that it lands on, but also when adatoms preferentially migrate over ascending step edges. This latter process can equalize long-range terrace width nonuniformities much more rapidly than can the former process. We also find that a slow lateral movement of terrace width distributions occurs when each adatom adheres to the step edges of the terrace that it lands on. More significantly, we find that a rapid lateral movement of terrace width distributions occurs when adatoms cross multiple step edges. This motion is especially fast when adatoms migrate distances that are comparable to or greater than the terrace width distribution period. We simulated the evolution of an experimentally observed (Al,Ga)Sb lateral superlattice (LSL) terrace width distribution, which led to quantitative estimates of the adatom migration characteristics present during the LSLs growth. At least one type of adatom, probably Ga, migrates nearly isotropically over many terraces. This method of determining adatom migration characteristics can be extended to any material system that allows LSL layers to be grown as terrace width markers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.354026
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Photoluminescence study of lateral carrier confinement and compositional intermixing in (Al,Ga)Sb lateral superlattices (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1676-1678 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have compared the photoluminescence properties of an (Al,Ga)Sb lateral superlattice (LSL) quantum well to those of an (Al,Ga)Sb alloy quantum well, with respect to recombination energy and polarization dependence. From the results we have deduced the compositional intermixing and lateral carrier confinement present in the LSL structure. We found that the LSL well luminesces at 36 meV lower than the alloy well, and that emitted light from the LSL well is more than twice as intense when its electric field is polarized parallel versus perpendicular to the LSL "wires.'' From these data we calculate that the lateral content of the LSL varies periodically between approximately 24% and 42% AlSb, and the maximum:minimum carrier density ratios are about 4:1 and 6:1 for electrons and heavy holes, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.107234
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Real-time control of molecular beam epitaxy by optical-based flux monitoring (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 63 (1993), S. 3131-3133 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have developed a real-time molecular beam epitaxy control system based on Al and Ga atomic beam resonant absorption of hollow cathode lamp emission. By continuously monitoring the absorption of Al and Ga beams during growth, this system accurately determines instantaneous growth rates and then integrates these over time to determine layer thickness. This information is used in real time for effusion cell shutter (and hence layer thickness) control. The accuracy and flexibility of this system is demonstrated here by growing AlAs/GaAs distributed Bragg reflectors with consistent layer thicknesses even though effusion cell temperatures were intentionally varied. In each instance the system automatically detected and compensated for the different growth rates, resulting in DBRs with center wavelengths controlled to within 0.3% of the target wavelength.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.110788
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Low resistance wavelength-reproducible p-type (Al,Ga)As distributed Bragg reflectors grown by molecular beam epitaxy (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 62 (1993), S. 1585-1587 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report the reproducible molecular beam epitaxial growth of Be-doped piecewise linearly graded (Al,Ga)As distributed Bragg reflectors that have vertical series resistivities near bulk values. For mirrors with three linear segments per interface, the center wavelength reproducibility is 0.1% and the series resistivity is as low as 1.8×10−5 Ω cm2 for hole concentrations of 5×1018 cm−3. Measured reflectivities of 6.0% per interface are comparable to conventional single-linear-grade mirrors. Vertical-cavity surface-emitting lasers incorporating these mirrors exhibit record-low voltage thresholds of less than 1.5 V.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.109608
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Method for accurate growth of vertical-cavity surface-emitting lasers (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 62 (1993), S. 1182-1184 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a method for accurate growth of vertical-cavity surface-emitting lasers (VCSELs). The method uses a single reflectivity spectrum measurement to determine the structure of the partially completed VCSEL at a critical point of growth. This information, along with the extracted growth rates, allows imprecisions in growth parameters to be compensated for during growth of the remaining structure, which can then be completed with very accurate critical dimensions. Using this method, we can now routinely grow lasing VCSELs with Fabry–Perot cavity resonance wavelengths controlled to within 0.5%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.108727
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Step-flow growth on strained surfaces: (Al,Ga)Sb tilted superlattices (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1751-1753 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have demonstrated the molecular beam epitaxial growth of (Al,Ga)Sb tilted superlattices (TSLs) on 2° vicinal (100) GaSb and GaAs substrates. The TSLs grown on GaSb substrates exhibit good AlSb/GaSb separation and a uniform short-range superlattice period. The TSLs grown on GaAs substrates are similar, except for the presence of threading dislocations and a decreased uniformity. The existence of TSLs proves that step-flow growth can occur in this material system, and in the presence of strain. Lateral fluctuations in the tilt angle of the superlattice are observed and are found to be caused by a nonuniform adatom distribution which is correlated with the surface step density.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104056
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Lateral motion of terrace width distributions during step-flow growth (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 61 (1992), S. 645-647 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have observed two phenomena that occur during (Al,Ga)Sb lateral superlattice (LSL) growth which have implications on our understanding of adatom/step edge interactions on vicinal surfaces: shifts of the lateral distribution of terrace widths in the direction of step propagation, and lateral variations in the superlattice tilt angle that are correlated with the terrace width distribution. Both phenomena can be explained with a model of step-flow growth that includes both asymmetric adatom attachment at step edges and anisotropic adatom crossing over multiple step edges. A comparison between numerical simulations of this model and experimentally observed (Al,Ga)Sb LSL terrace width distributions leads to quantitative estimates of adatom migration characteristics. We find that at least one type of adatom, probably Ga, has a migration length equivalent to several terrace widths, and moves up and down step edges nearly isotropically. This method of determining adatom migration characteristics can be extended to any material that LSL layers can be grown above and below as terrace width markers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.107809
    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...