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

First-principles calculations have evolved from mere aids in explaining and supporting experiments to powerful tools for predicting new materials and their properties. In the first part of this review we describe the state-of-the-art computational methodology for calculating the structure and energetics of point defects and impurities in semiconductors. We will pay particular attention to computational aspects which are unique to defects or impurities, such as how to deal with charge states and how to describe and interpret transition levels. In the second part of the review we will illustrate these capabilities with examples for defects and impurities in nitride semiconductors. Point defects have traditionally been considered to play a major role in wide-band-gap semiconductors, and first-principles calculations have been particularly helpful in elucidating the issues. Specifically, calculations have shown that the unintentional n-type conductivity that has often been observed in as-grown GaN cannot be a...

First-principles calculations for defects and impurities: Applications to III-nitrides

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

Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The p...

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Luminescence properties of defects in GaN

The role of extended and point defects, and key impurities such as C, O, and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation, and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes, and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

Gan : processing, defects, and devices

A heterojunction transistor may include a channel layer (14) comprising a Group III nitride, a barrier layer (16) comprising a Group III nitride on the channel layer, and an energy barrier (30, 32, 34) comprising a layer of a Group III nitride including indium on the channel layer such that the channel layer is between the barrier layer and the energy barrier. The barrier layer may have a bandgap greater than a bandgap of the channel layer, and a concentration of indium (In) in the energy barrier may be greater than a concentration of indium (In) in the channel layer. Related methods are also discussed.

Heterojunction transistors including energy barriers and related methods

The fundamental optical properties of AgGaTe2, a nonlinear optical semiconductor are reported These properties include birefringence, indices of refraction, infrared transmission, and the temperature dependence of the band gap The average index for wavelengths greater than several microns was found to be 30 The birefringence was found to be rather large and to range from a near band edge value of 0038 at 13 μm to a value of 0017 at 15 μm Additionally, native defect related sub-bandgap absorption, photoluminescence, and electrical transport have been studied in these nominally undoped p-type crystals An activation energy associated with these defects was determined to be 03 eV and the corresponding photoluminescence and absorption data showed, respectively, a broad asymmetric emission band centered at 08 eV and two bands at 095 and 101 eV, the absorption band at 095 eV being the most intense The measured properties were utilized to assess the potential of AgGaTe2 for the wavelength conversio

Infrared properties of aggate2, a nonlinear optical chalcopyrite semiconductor

Semiconductor structure and method of fabricating a semiconductor structure are provided that include a substrate having a first in-plane unstrained lattice constant, a first layer comprising a first semiconductor material on the substrate and having a second in-plane unstrained lattice constant that is different from the first in-plane unstrained lattice constant and a variable mismatch layer comprising a second semiconductor material disposed between the substrate and the first layer. The variable mismatch layer is configured to reduce stress in the first layer to below a level of stress resulting from growth of the first layer directly on the substrate. The variable mismatch layer may be a layer having a strained in-plane lattice constant that substantially matches the unstrained lattice constant of the first layer.

Strain compensated semiconductor structures and methods of fabricating strain compensated semiconductor structures

Sub-02-/spl mu/m AlGaN/GaN HEMTs were successfully scaled to 105 mm gate-width with minor gain reduction On-chip single-stage amplifiers exhibited gains of 8 dB and 75 dB, as well as output powers of 36 W and 35 W, at 30 GHz and 35 GHz, respectively This multi-watt output power at millimeter-wave frequencies well exceeded previous state-of-the-art for a GaN HEMT and is comparable to that from 6-7 times larger GaAs-based devices

3.5-watt AlGaN/GaN HEMTs and amplifiers at 35 GHz

Group III Nitride based field effect transistor (FETs) are provided having a power degradation of less than about 3.0 dB when operated at a drain-to-source voltage (VDS) of about 56 volts, a gate to source voltage (Vgs) of from about -8 to about -14 volts and a temperature of about 140 °C for at least about 10 hours.

Adam William Saxler

Papers

Heterojunction transistors including energy barriers and related methods

Infrared properties of aggate2, a nonlinear optical chalcopyrite semiconductor

Strain compensated semiconductor structures and methods of fabricating strain compensated semiconductor structures

3.5-watt AlGaN/GaN HEMTs and amplifiers at 35 GHz

Group III nitride field effect transistors (FETS) capable of withstanding high temperature reverse bias test conditions