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
    Deposition and surface characterization of high quality single crystal GaN layers (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 3108-3110 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Recently, using low pressure metalorganic chemical vapor deposition we grew extremely high quality single crystal GaN films over basal plane sapphire substrates. Optimization of the buffer layers and the total film thickness played a key role in determining the electrical, optical, crystalline and surface qualities. In this communication we present the surface characterization results for these high quality GaN layers. Reflection high energy electron diffraction, low energy electron diffraction (LEED), and electron energy loss spectroscopy data are presented for clean GaN surfaces. The cleaning procedure was developed using Auger electron spectroscopy analysis. These electron diffraction data indicate the grown surface to be excellent single crystal GaN with a wurtzite structure. To the best of our knowledge ours is the first reported LEED data for single crystal GaN.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.352999
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Cathodoluminescence of AlN–GaN short period superlattices (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 2378-2382 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Cathodoluminescence of AlN–GaN short period superlattice films was measured at 6 K, 77 K, and room temperature. The superlattice films were deposited using a switched atomic layer metalorganic chemical vapor deposition process onto a buffer layer of either AlN or GaN, which was deposited on basal plane sapphire substrates. The individual AlN and GaN layers of the superlattice films ranged in thickness from 2.6 to 20.8 A(ring). The cathodoluminescence of these samples was measured at several electron acceleration voltages to allow depth profiling of the samples. This allows the region of the sample (superlattice film, buffer layer, and substrate) from which the spectral features originate to be determined. A spectral peak in the ultraviolet region above the 3.5 eV band gap of GaN has been observed in all the superlattice samples studied to date. Our results indicate that the location of this peak is determined by quantum confinement in the GaN layers. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363726
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Growth of high optical and electrical quality GaN layers using low-pressure metalorganic chemical vapor deposition (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 526-527 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on the low-pressure metalorganic chemical vapor deposition of high quality single-crystal GaN layers over basal plane sapphire substrates. Optimization of growth conditions resulted in material with carrier densities of 1017 /cm3 at room temperature and corresponding mobilities around 350 cm2 /V s. The photoluminescence linewidths improved from 160 meV [full width at half maximum (FWHM)] to 25 meV (FWHM). With improved material quality we were able to observe the polar optical mode and the ionized impurity scattering regimes in the mobility versus temperature data. Good quality Schottky barriers were formed on the as-grown material using a tungsten probe and an alloyed indium contact. Our observations indicate a direct correlation between electrical and optical characteristics of good material and strongly question nitrogen vacancies as the sole explanation for the high carrier densities observed in poor quality GaN growths.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104575
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    High transconductance heterostructure field-effect transistors based on AlGaN/GaN (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 69 (1996), S. 794-796 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on the fabrication and characterization of Al0.15Ga0.85N/GaN heterostructure field-effect transistors (HFETs) with transconductance as high as 120 mS/mm and saturated current density of 0.35 A/mm for a device with a gate length and width of 1 and 100 μm. This represents one of the best results for such device. A comparison of the maximum transconductance of devices on wafers with different channel conductance is presented to analyze the factors limiting the performance. Our data indicates the series resistance between the source and drain to be the limiting factor for the maximum dc transconductance. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.117894
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Electron beam induced current measurements of minority carrier diffusion length in gallium nitride (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 69 (1996), S. 2531-2533 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Minority carrier diffusion length in epitaxial GaN layers was measured as a function of majority carrier concentration and temperature. The diffusion length of holes in n-type GaN is found to decrease from 3.4 to 1.2 μm in the doping range of 5×1015–2×1018 cm−3. The experimental results can be fitted by assuming the Einstein relation and by the experimental dependence of hole mobilities on carrier concentration. The low injection carrier lifetime of ∼15 ns, used in the fit, is largely independent of the doping level. The diffusion length, measured for ∼5×1015 and 2×1018 cm−3 dopant concentrations, shows an increase with increasing temperature, characterized by an activation energy Ea of ∼90 meV, independent of the impurity concentration. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.117729
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Deposition of high quality wurtzite GaN films over cubic (111) MgAl2O4 substrates using low pressure metalorganic chemical vapor deposition (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 1129-1131 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report the deposition of high quality single-crystal wurtzite GaN films on cubic (111) spinel (MgAl2O4) substrates. The room-temperature electron mobility and the optically pumped stimulated emission threshold for these films are nearly identical to those of films deposited on basal plane sapphire. Using cross sectional high resolution TEM we have determined the following orientation relationship between the film and the substrate: [0001]GaN//[111]MgAl2O4 and [112¯0]GaN//[110]MgAl2O4. This should provide a common cleavage plane for (111) spinel and the wurtzite GaN films over it. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.115735
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    High electron mobility transistor based on a GaN-AlxGa1−xN heterojunction (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 63 (1993), S. 1214-1215 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this letter we report the fabrication and dc characterization of a high electron mobility transistor (HEMT) based on a n-GaN-Al0.14Ga0.86N heterojunction. The conduction in our low pressure metalorganic chemical vapor deposited heterostructure is dominated by two-dimensional electron gas at the heterostructure interface. HEMT devices were fabricated on ion-implant isolated mesas using Ti/Au for the source drain ohmic and TiW for the gate Schottky. For a device with a 4 μm gate length (10 μm channel opening, i.e., source-drain separation), a transconductance of 28 mS/mm at 300 K and 46 mS/mm at 77 K was obtained at +0.5 V gate bias. Complete pinchoff was observed for a −6 V gate bias.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.109775
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Low pressure metalorganic chemical vapor deposition of AIN over sapphire substrates (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 61 (1992), S. 2539-2541 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this letter we report the deposition of high quality single-crystal films of AIN over basal plane sapphire substrates. A conventional low pressure metalorganic chemical vapor deposition (LPMOCVD) system was used for all the growths reported here. We present the results of conventional and switched atomic layer epitaxial (SALE) depositions. Conventional LPMOCVD yielded single-crystal AIN films at temperatures in excess of 750 °C. The ALE process in contrast produced extremely smooth single-crystal AIN layers at temperatures as low as 450 °C. To the best of our knowledge this is the lowest ever reported for chemical vapor deposition of single-crystal AIN. X-ray and optical characterization data are presented to compare the quality of the material resulting from the two deposition techniques.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.108144
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Schottky barrier photodetector based on Mg-doped p-type GaN films (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 63 (1993), S. 2455-2456 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this letter we report the fabrication and characterization of Schottky barrier photodetectors on p-type GaN films. These films were grown over basal plane sapphire substrates using low pressure metalorganic chemical vapor deposition and magnesium as the p-type dopant. The current-voltage and capacitance-voltage characteristics were measured for Ti/Au Schottky barriers for a film with a p doping of 7×1017 cm−3. We measured a 1.5 V forward turn on and a 3 V reverse breakdown. The zero bias responsivity of a detector with 1 mm2 area was measured to be 0.13 A/W. For these photovoltaic detectors, the photoresponse was nearly constant from 200 to 365 nm and fell sharply by several orders of magnitude for wavelengths above 365 nm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.110473
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Atomic layer epitaxy of GaN over sapphire using switched metalorganic chemical vapor deposition (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1366-1368 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this letter we report the first switched atomic layer epitaxy (SALE) of single crystal GaN over basal plane sapphire substrates. A low pressure metalorganic chemical vapor deposition (LPMOCVD) system was used for the epilayer depositions. In contrast to conventional LPMOCVD requiring temperatures higher than 700 °C, the SALE process resulted in single crystal insulating GaN layers at growth temperatures ranging from 900 to 450 °C. The band-edge transmission and the photoluminescence of the films from the SALE process were comparable to the best LPMOCVD films. To the best of our knowledge this is the first report of insulating GaN films which show excellent band-edge photoluminescence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.107484
    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...