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 comprising a Group III nitride, a barrier layer comprising a Group III nitride on the channel layer, and an energy barrier 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

Significant progress has been made in the
development of SiC MESFETs and MMIC power
amplifiers manufactured on 3-inch high purity semiinsulating
(HPSI) 4H-SiC substrates. Wide bandwidth
circuits using both 10 Watt and 60 watt MESFETs are
presented. These MESFETs show no degradation after
RFHTOL at a baseplate of 90°C for 4000 hours. High
power SiC MMIC amplifiers are shown with excellent yield
and repeatability using a released foundry process. GaN
HEMTs on HPSI SiC are reported with >30 W/mm RF
output power density, and 10 GHz PAE of 72% is also
demonstrated for lower voltage devices. Finally, a GaN
HEMT operating life of over 500 hours at a TJ =160°C is
also reported.

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SiC and GaN Based Transistor and Circuit Advances

Simultaneous growth of two differently oriented GaN epilayers on (1 1 · 0) sapphire II. A growth model of (0 0 · 1) and (10 · 0) GaN

A type-II superlattice (SL) of InAs-InGaSb has been grown on a compliant GaAs substrate by molecular beam epitaxy. This SL was designed for photoconductive infrared (IR) detection in the long wavelength IR band. The spectral photoresponse of this SL shows a sharp onset at 76.9 meV and a corresponding cutoff wavelength at 13.9 /spl mu/m. A sixfold increase in the peak photoresponse was measured in comparison to the response from a similar SL on a standard GaSb substrate.

Type-II superlattice photodetector on a compliant GaAs substrate

High electron mobility transistors are provided that include a non-uniform aluminum concentration AlGaN based cap layer having a high aluminum concentration adjacent a surface of the cap layer that is remote from the barrier layer on which the cap layer is provided. High electron mobility transistors are provided that include a cap layer having a doped region adjacent a surface of the cap layer that is remote from the barrier layer on which the cap layer is provided. Graphitic BN passivation structures for wide bandgap semiconductor devices are provided. SiC passivation structures for Group III-nitride semiconductor devices are provided. Oxygen anneals of passivation structures are also provided. Ohmic contacts without a recess are also provided.

Adam William Saxler

Papers

Heterojunction transistors including energy barriers

SiC and GaN Based Transistor and Circuit Advances

Simultaneous growth of two differently oriented GaN epilayers on (1 1 · 0) sapphire II. A growth model of (0 0 · 1) and (10 · 0) GaN

Type-II superlattice photodetector on a compliant GaAs substrate

Transistors having buried n-type and p-type regions beneath the source region