scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Valence‐band discontinuities of wurtzite GaN, AlN, and InN heterojunctions measured by x‐ray photoemission spectroscopy

29 Apr 1996-Applied Physics Letters (American Institute of Physics)-Vol. 68, Iss: 18, pp 2541-2543
TL;DR: In this paper, the valence band discontinuities at various wurtzite GaN, AlN, and InN heterojunctions were measured by means of x-ray photoemission spectroscopy.
Abstract: The valence‐band discontinuities at various wurtzite GaN, AlN, and InN heterojunctions were measured by means of x‐ray photoemission spectroscopy. A significant forward–backward asymmetry was observed in the InN/GaN–GaN/InN and InN/AlN–AlN/InN heterojunctions. The asymmetry was understood as a piezoelectric strain effect. We report the valence band discontinuities for InN/GaN=1.05±0.25 eV, GaN/AlN=0.70±0.24 eV, and InN/AlN=1.81±0.20 eV, all in the standard type I lineup. These values obey transitivity to within the experimental accuracy. Tables of photoemission core level binding energies are reported for wurtzite GaN, AlN, and InN.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article, the authors present a comprehensive, up-to-date compilation of band parameters for the technologically important III-V zinc blende and wurtzite compound semiconductors.
Abstract: We present a comprehensive, up-to-date compilation of band parameters for the technologically important III–V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned relative to any other.

6,349 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated the role of spontaneous and piezoelectric polarization on the carrier confinement at GaN/AlGaN and AlGaN/GaN interfaces.
Abstract: Carrier concentration profiles of two-dimensional electron gases are investigated in wurtzite, Ga-face AlxGa1−xN/GaN/AlxGa1−xN and N-face GaN/AlxGa1−xN/GaN heterostructures used for the fabrication of field effect transistors. Analysis of the measured electron distributions in heterostructures with AlGaN barrier layers of different Al concentrations (0.15

2,581 citations

Journal ArticleDOI
TL;DR: In this paper, a comprehensive and up-to-date compilation of band parameters for all of the nitrogen-containing III-V semiconductors that have been investigated to date is presented.
Abstract: We present a comprehensive and up-to-date compilation of band parameters for all of the nitrogen-containing III–V semiconductors that have been investigated to date. The two main classes are: (1) “conventional” nitrides (wurtzite and zinc-blende GaN, InN, and AlN, along with their alloys) and (2) “dilute” nitrides (zinc-blende ternaries and quaternaries in which a relatively small fraction of N is added to a host III–V material, e.g., GaAsN and GaInAsN). As in our more general review of III–V semiconductor band parameters [I. Vurgaftman et al., J. Appl. Phys. 89, 5815 (2001)], complete and consistent parameter sets are recommended on the basis of a thorough and critical review of the existing literature. We tabulate the direct and indirect energy gaps, spin-orbit and crystal-field splittings, alloy bowing parameters, electron and hole effective masses, deformation potentials, elastic constants, piezoelectric and spontaneous polarization coefficients, as well as heterostructure band offsets. Temperature an...

2,525 citations

Journal ArticleDOI
TL;DR: In this paper, a combination of high resolution x-ray diffraction, atomic force microscopy, Hall effect, and capacitance-voltage profiling measurements is used to calculate the polarization induced sheet charge bound at the AlGaN/GaN interfaces.
Abstract: Two dimensional electron gases in Al x Ga 12x N/GaN based heterostructures, suitable for high electron mobility transistors, are induced by strong polarization effects. The sheet carrier concentration and the confinement of the two dimensional electron gases located close to the AlGaN/GaN interface are sensitive to a large number of different physical properties such as polarity, alloy composition, strain, thickness, and doping of the AlGaN barrier. We have investigated these physical properties for undoped and silicon doped transistor structures by a combination of high resolution x-ray diffraction, atomic force microscopy, Hall effect, and capacitance‐voltage profiling measurements. The polarization induced sheet charge bound at the AlGaN/GaN interfaces was calculated from different sets of piezoelectric constants available in the literature. The sheet carrier concentration induced by polarization charges was determined

1,439 citations

Journal ArticleDOI
TL;DR: In this article, the chemical and thermal stability of epitaxial nitride films is discussed in relation to the problems of deposition processes and the advantages for applications in high-power and high-temperature devices.
Abstract: Recent research results pertaining to InN, GaN and AlN are reviewed, focusing on the different growth techniques of Group III-nitride crystals and epitaxial films, heterostructures and devices. The chemical and thermal stability of epitaxial nitride films is discussed in relation to the problems of deposition processes and the advantages for applications in high-power and high-temperature devices. The development of growth methods like metalorganic chemical vapour deposition and plasma-induced molecular beam epitaxy has resulted in remarkable improvements in the structural, optical and electrical properties. New developments in precursor chemistry, plasma-based nitrogen sources, substrates, the growth of nucleation layers and selective growth are covered. Deposition conditions and methods used to grow alloys for optical bandgap and lattice engineering are introduced. The review is concluded with a description of recent Group III-nitride semiconductor devices such as bright blue and white light-emitting diodes, the first blue-emitting laser, high-power transistors, and a discussion of further applications in surface acoustic wave devices and sensors.

1,386 citations

References
More filters
Journal ArticleDOI
TL;DR: In this article, the conduction band edge discontinuity ΔEc = 0.56 eV at n−CdS/p−InP junctions is reported, and the performance of this discontinuity and others are compared with photoemission data and with Van Vechten's extension of these data to many tetrahedrally coordinated semiconductors.
Abstract: The discontinuity ΔEc=0.56 eV in the conduction band edge at n‐CdS/p‐InP junctions is reported. This discontinuity and others are compared with photoemission data and with Van Vechten’s extension of these data to many tetrahedrally coordinated semiconductors. Agreement between measured discontinuities and theoretical predictions is very good. Predictions are made for band parameters pertinent to interfaces involving AIIBIVCV2 compounds with zinc blende, chalcopyrite, or wurtzite crystal structures.

208 citations