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.

Band parameters for III–V compound semiconductors and their alloys

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...

Band parameters for nitrogen-containing semiconductors

Metamaterials exhibit numerous novel effects1,2,3,4,5 and operate over a large portion of the electromagnetic spectrum6,7,8,9,10. Metamaterial devices based on these effects include gradient-index lenses11,12, modulators for terahertz radiation13,14,15 and compact waveguides16. The resonant nature of metamaterials results in frequency dispersion and narrow bandwidth operation where the centre frequency is fixed by the geometry and dimensions of the elements comprising the metamaterial composite. The creation of frequency-agile metamaterials would extend the spectral range over which devices function and, further, enable the manufacture of new devices such as dynamically tunable notch filters. Here, we demonstrate such frequency-agile metamaterials operating in the far-infrared by incorporating semiconductors in critical regions of metallic split-ring resonators. For this first-generation device, external optical control results in tuning of the metamaterial resonance frequency by ∼20%. Our approach is integrable with current semiconductor technologies and can be implemented in other regions of the electromagnetic spectrum. Metamaterials that possess frequency tunability enable new device functions. By external optical control through the incorporation of semiconductors in metallic split-ring resonators, the researchers provide an elegant solution to frequency-agile terahertz metamaterials.

http://www.bc.edu/content/dam/files/schools/cas_sites/physics/pdf/Padilla/Nature_Photonics_2_295_2008.pdf

Experimental demonstration of frequency-agile terahertz metamaterials

Theoretical investigations of doping of several wide-gap materials suggest a number of rather general, practical “doping principles” that may help guide experimental strategies for overcoming doping bottlenecks.

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Practical doping principles

Doping limits in semiconductors are discussed in terms of the amphoteric defect model (ADM). It is shown that the maximum free electron or hole concentration that can be achieved by doping is an intrinsic property of a given semiconductor and is fully determined by the location of the semiconductor band edges with respect to a common energy reference, the Fermi level stabilization energy. The ADM provides a simple phenomenological rule that explains experimentally observed trends in free carrier saturation in a variety of semiconductor materials and their alloys. The predictions of a large enhancement of the maximum electron concentration in III–N–V alloys have been recently confirmed by experiment.

Intrinsic limitations to the doping of wide-gap semiconductors

GaNAs films grown on GaAs(001) substrates by metalorganic molecular beam epitaxy were studied by high-resolution x-ray diffraction (XRD) mapping measurements. The lattice constants of epitaxial films are usually estimated from symmetric and asymmetric XRD 2θ−θ measurements. In this study, it is pointed out that the consideration of the tilt angle between the GaAs(115) and GaNAs(115) planes caused by elastic deformation of the films is crucial to determine the lattice constants of the GaNAs films coherently grown on GaAs substrates. Mapping measurements of (115) XRD (2θ−θ)−Δω were performed for this purpose. The band gap energy of the films was determined by Fourier transform absorption spectroscopy measurements. The band gap energy bowing measured up to the N composition of 4.5% will be discussed by comparing with other measurements and theoretical calculations.

/pdf/reexamination-of-n-composition-dependence-of-coherently-x807vyio6j.pdf

Reexamination of N composition dependence of coherently grown GaNAs band gap energy with high-resolution x-ray diffraction mapping measurements

We have observed a significant reduction in the temperature dependence of the absorption-edge energy in GaNxAs1−x alloys with x<0.04. The effect has been analyzed in terms of the recently introduced band anticrossing model that considers a coupling of the temperature-independent localized states of substitutional nitrogen atoms and the temperature-dependent extended states of GaAs. The model explains very well the alloy composition and the temperature dependence of the absorption-edge energy. We also compare the parameters that determine the temperature dependence of the band-gap energies in GaNAs and GaInNAs alloys.

Role of nitrogen in the reduced temperature dependence of band-gap energy in GaNAs

The temperature dependence of band gap energies of GaAsN alloys was studied with absorption measurements. As the N concentration in GaAsN increased, the temperature dependence of the band gap energy was clearly reduced in comparison with that of GaAs. The redshift of the absorption edge in GaAsN for the temperature increase from 25 to 297 K was reduced to 60% of that of GaAs for the N concentration larger than ∼1%. The differential temperature coefficient of the energy gap at room temperature was also reduced to 70% of that of GaAs. The main factor for this reduced temperature dependence in GaAsN was attributed to the transition from band-like states to nitrogen-related localized states with detailed studies of the temperature-induced shift of the absorption edge.

/pdf/temperature-dependence-of-band-gap-energies-of-gaasn-alloys-24rmyl9cu1.pdf

Temperature dependence of band gap energies of GaAsN alloys

GaNAs layers have been successfully grown on GaAs(001) substrates by metalorganic molecular beam epitaxy using monomethylhydrazine (MMHy) as a N source. The N composition in GaNAs increased with decreasing growth temperature and with the increasing MMHy precursor ratio in the group-V precursors. We obtained a N composition of 7.2% in GaNAs. With the increased N composition, the absorption spectra shifted to lower energy and the absorption coefficient increased by one order of magnitude. When the N composition in GaNAs is less than 1%, the measured bandgap energy is very close to the theoretical bandgap energy based on the dielectric model. However, for N composition larger than 1%, the bandgap energy deviated considerably from the dielectric model, and approached the theoretical bandgap energy based on the first-principles supercell models.

https://iopscience.iop.org/article/10.1143/JJAP.36.L1572/pdf

Bandgap energy of GaNAs alloys grown on (001) GaAs by metalorganic molecular beam epitaxy

The growth of GaNAs and related alloys has been studied using metal–organic molecular beam epitaxy. The lattice mismatch of GaNAs layers grown on GaAs induces lattice relaxation, the details of which are investigated with a mapping measurement of x-ray diffraction. The experimental results are compared to the calculated value of the critical thickness for the generation of misfit dislocations. It is shown that the surface morphology changes with the nitrogen (N) incorporation and, especially, wire-like surfaces associated with lateral compositional modulation are observed in a certain range of N compositions and with a thickness of more than 1 μm. The effects of indium and selenium doping on the N incorporation in GaNAs alloys are also discussed.

Katsuhiro Uesugi

Papers

Reexamination of N composition dependence of coherently grown GaNAs band gap energy with high-resolution x-ray diffraction mapping measurements

Role of nitrogen in the reduced temperature dependence of band-gap energy in GaNAs

Temperature dependence of band gap energies of GaAsN alloys

Bandgap energy of GaNAs alloys grown on (001) GaAs by metalorganic molecular beam epitaxy

Growth and structural characterization of III–N–V semiconductor alloys