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31 May 1999

Volume 74, Issue 22, pp. 3245-3412

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Observation of growth modes during metal-organic chemical vapor deposition of GaN

G. B. Stephenson, J. A. Eastman, C. Thompson, O. Auciello, L. J. Thompson, A. Munkholm, P. Fini, S. P. DenBaars, and J. S. Speck

Appl. Phys. Lett. 74, 3326 (1999); http://dx.doi.org/10.1063/1.123333 (3 pages) | Cited 22 times

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We present real-time surface x-ray scattering measurements during homoepitaxial growth of GaN by metal-organic chemical vapor deposition. We observed intensity oscillations corresponding to the completion of each monolayer during layer-by-layer growth. The growth rate was found to be temperature independent and Ga-transport limited. Transitions between step-flow, layer-by-layer, and three-dimensional growth modes were determined as a function of temperature and growth rate. © 1999 American Institute of Physics.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.-a Thin film structure and morphology
81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.05.Ea III-V semiconductors
78.70.Ck X-ray scattering

The influence of diffusion temperature and ion dose on proximity gettering of platinum in silicon implanted with alpha particles at low doses

D. C. Schmidt, B. G. Svensson, S. Godey, E. Ntsoenzok, J. F. Barbot, and C. Blanchard

Appl. Phys. Lett. 74, 3329 (1999); http://dx.doi.org/10.1063/1.123334 (3 pages) | Cited 7 times

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Platinum has been diffused into epitaxial n-type silicon at 600, 650, and 700 °C for 30 min following implantation with 3.3 MeV alpha particles. The doses employed were between 1×1011 and 1×1014 He+ cm−2. Thereafter the samples were characterized using deep level transient spectroscopy (DLTS). The samples diffused at 700 °C show only the deep level at 0.23 eV below the conduction band that is attributed to substitutional platinum. DLTS profiling reveals a decoration of the region of maximal damage by the platinum for lower doses while for higher ones the platinum concentration is observed to decrease or vanish in this region. In addition, other deep levels may appear (so-called K lines). As the implantation dose increases, so does the platinum concentration following diffusion at 700 °C at the shallow end of the DLTS working region. It is shown that, by controlling the amount of implantation induced defects and the diffusion temperature, one can steer the amount of platinum that arrives in the region of maximal damage. © 1999 American Institute of Physics.
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61.72.Yx Interaction between different crystal defects; gettering effect
81.05.Cy Elemental semiconductors
61.82.Fk Semiconductors
85.40.Ry Impurity doping, diffusion and ion implantation technology
81.65.Tx Gettering
71.55.Cn Elemental semiconductors
61.80.Jh Ion radiation effects
66.30.J- Diffusion of impurities
61.72.uf Ge and Si
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Metal–semiconductor–metal photodiodes fabricated from thin-film diamond

Hui Jin Looi, Michael D. Whitfield, and Richard B. Jackman

Appl. Phys. Lett. 74, 3332 (1999); http://dx.doi.org/10.1063/1.123335 (3 pages) | Cited 14 times

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A metal–semiconductor–metal Schottky barrier photodetector has been fabricated on a “hydrogen-doped” surface-conducting chemical vapor deposition (CVD) diamond. The device is fabricated in one step by forming two back-to-back aluminum Schottky diodes on the p-type surface. This simple process is compatible with previously reported metal–semiconductor field-effect transistor fabrication on this type of CVD diamond and offers the prospect of the monolithic integration of a ultraviolet detector and active circuitry. Preliminary electrical and optical characteristics of the device have been measured, including the spectral response over the range 180–800 nm. The device exhibits a linear response with the applied optical power at 220 nm, operates at a bias of only 2 V, and shows visible blind characteristics, with a spectral discrimination of three orders of magnitude as determined from the ratio of 200–550 nm responses. © 1999 American Institute of Physics.
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78.66.Db Elemental semiconductors and insulators
85.60.Dw Photodiodes; phototransistors; photoresistors
85.30.Hi Surface barrier, boundary, and point contact devices
85.60.Gz Photodetectors (including infrared and CCD detectors)
73.40.Sx Metal-semiconductor-metal structures
81.05.Cy Elemental semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Segregation coefficient of beryllium in traveling-solvent-grown BeyZn1−ySe1−xTex bulk crystals using tellurium solution

Kenji Maruyama, Ken Suto, and Jun-ichi Nishizawa

Appl. Phys. Lett. 74, 3335 (1999); http://dx.doi.org/10.1063/1.123336 (3 pages) | Cited 4 times

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Quaternary bulk single crystals of BeyZn1−ySe1−xTex have been grown using the traveling-solvent method with a tellurium solution at a peak temperature of 1050 °C. BeyZn1−ySe1−xTex mixed crystals contain beryllium from 0.02 to 5.0 at. % and tellurium from 1.8 to 5.5 at. % (0.03<x<0.11, 0.0004<y<0.10). The best full width of half maximum of the x-ray rocking curve shows 33 arcsec and the best etch pit density is 3.0×105/cm2. The beryllium segregation coefficient was evaluated from the beryllium composition profiles. We obtained a beryllium segregation coefficient of k = 1.65±0.45. Compositionally uniform BeZnSeTe bulk crystals matching the ZnSe in the lattice constant can be grown. Large parts of the BeZnSeTe ingot are anticipated to match the ZnSe lattice, because the beryllium segregation coefficient is close to unity. © 1999 American Institute of Physics.
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81.05.Dz II-VI semiconductors
81.10.Dn Growth from solutions
64.75.-g Phase equilibria
61.66.Fn Inorganic compounds
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)

Temperature dependence of the thermo-optic coefficient in crystalline silicon between room temperature and 550 K at the wavelength of 1523 nm

G. Cocorullo, F. G. Della Corte, and I. Rendina

Appl. Phys. Lett. 74, 3338 (1999); http://dx.doi.org/10.1063/1.123337 (3 pages) | Cited 56 times

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The temperature dependence of the thermo-optic coefficient for crystalline silicon has been measured in the temperature range between room temperature and 550 K at the wavelength of 1523 nm by means of an interferometric technique. This technique, which requires a very simple experimental setup, is based on the observation of the fringe pattern produced by temperature changes in a Fabry–Perot resonator. Measurement results indicate that the thermo-optic coefficient is independent on the sample doping and crystal plane orientation. The experimental data appear to be in agreement with the few values reported to date at this important wavelength. The temperature dependence of the excitonic band gap is also calculated by fitting these data with a recently introduced model of ∂n/∂T. © 1999 American Institute of Physics.
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78.20.N- Thermo-optic effects
78.20.nb Photothermal effects
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
71.35.Cc Intrinsic properties of excitons; optical absorption spectra

Donor–acceptor-pair spectroscopy of GaAs grown in space ultravacuum

G. Neu, M. Teisseire, A. Freundlich, C. Horton, and A. Ignatiev

Appl. Phys. Lett. 74, 3341 (1999); http://dx.doi.org/10.1063/1.123338 (3 pages)

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Selective pair luminescence has been used to identify shallow acceptor levels in undoped GaAs epilayers grown by molecular beam epitaxy (MBE) in the ultrahigh vacuum of space generated in the wake of the free-flying Wake Shield Facility satellite (Space Shuttle Endeavor mission STS69). The low-temperature photoluminescence spectra are typical of high-purity GaAs. Unlike for conventional MBE-grown undoped GaAs where the near-band-edge excitonic luminescence is dominated by acceptor-bound excitons, the space-grown GaAs near-band-edge luminescence was found to be dominated by donor-bound excitons. The comparison of measured ground (1S3/2) and excited acceptor states to published acceptor spectra leads to the identification of CAs as the main residual acceptor impurity in the layer. Furthermore, the existence of a donor–acceptor-pair emission band demonstrates that a second acceptor is electronically active. Excited-state spectroscopy clearly identifies the second residual acceptor as ZnGa, which is scarcely observed for GaAs samples grown in terrestrial MBE systems. In addition, the absence of a Be impurity, introduced in large quantities to the growth environment prior to the epilayer growth, suggests a minimized memory effect on the free flyer as opposed to terrestrial chambers. © 1999 American Institute of Physics.
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78.66.Fd III-V semiconductors
71.55.Eq III-V semiconductors
78.55.Cr III-V semiconductors
71.35.Cc Intrinsic properties of excitons; optical absorption spectra

The band-gap bowing of AlxGa1−xN alloys

S. R. Lee, A. F. Wright, M. H. Crawford, G. A. Petersen, J. Han, and R. M. Biefeld

Appl. Phys. Lett. 74, 3344 (1999); http://dx.doi.org/10.1063/1.123339 (3 pages) | Cited 66 times

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The band gap of AlxGa1−xN is measured for the composition range 0 ⩽ x<0.45; the resulting bowing parameter, b = +0.69 eV, is compared to 20 previous works. A correlation is found between the measured band gaps and the methods used for epitaxial growth of the AlxGa1−xN: directly nucleated or buffered growths of AlxGa1−xN initiated on sapphire at temperatures T>800 °C usually lead to stronger apparent bowing (b>+1.3 eV); while growths initiated using low-temperature buffers on sapphire, followed by high-temperature growth, lead to weaker bowing (b<+1.3 eV). Extant data suggest that the intrinsic band-gap bowing parameter for AlGaN alloys is b = +0.62(±0.45) eV. © 1999 American Institute of Physics.
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71.20.Nr Semiconductor compounds
78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
78.55.Cr III-V semiconductors
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Evidence for coupling of Si–Si lattice vibration and Si–D wagging vibration in deuterated amorphous silicon

An Shih, Si-Chen Lee, and Chih-ta Chia

Appl. Phys. Lett. 74, 3347 (1999); http://dx.doi.org/10.1063/1.123340 (3 pages) | Cited 9 times

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The Raman spectra of hydrogenated and deuterated amorphous silicon films (a-Si:H, a-Si:D) have been investigated. It is suggested that the asymmetrical broadening of the transverse-optical (TO) Raman peak of a-Si:D compared to the TO Raman peak of a-Si:H results from the coupling between the Si–D wagging mode and the Si–Si TO phonon mode rather than the structural difference. © 1999 American Institute of Physics.
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78.35.+c Brillouin and Rayleigh scattering; other light scattering
63.50.-x Vibrational states in disordered systems

Resonant two-photon excitation of silicon nanocrystals

J. Diener, D. I. Kovalev, G. Polisski, and F. Koch

Appl. Phys. Lett. 74, 3350 (1999); http://dx.doi.org/10.1063/1.123341 (3 pages) | Cited 5 times

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We have studied generation of visible photoluminescence (PL) in porous silicon (PSi) under resonant two-photon excitation. While the temporal decays of the resonant photoluminescence excited by one- and two-photon absorption are identical and show the same temperature dependence, the PL response differs significantly near the excitation energy. Contrary to one-photon excitation, no spectral gap between the excitation energy and the onset of the two-photon excited PL is observed. This is explained in the framework of selection rules for dipole allowed and forbidden optical exciton transitions in silicon nanocrystals. © 1999 American Institute of Physics.
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78.55.Mb Porous materials
78.55.Ap Elemental semiconductors
78.47.-p Spectroscopy of solid state dynamics
71.35.Cc Intrinsic properties of excitons; optical absorption spectra

Photoreflectance investigations of the bowing parameter in AlGaN alloys lattice-matched to GaN

Tomasz J. Ochalski, Bernard Gil, Pierre Lefebvre, Nicolas Grandjean, Mathieu Leroux, Jean Massies, Shuji Nakamura, and Hadis Morkoç

Appl. Phys. Lett. 74, 3353 (1999); http://dx.doi.org/10.1063/1.123342 (3 pages) | Cited 18 times

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Room temperature photoreflectance investigations have been performed on a series of AlGaN layers grown both by metalorganic vapor phase epitaxy and molecular beam epitaxy on c-plane sapphire substrates. The aluminum composition was ranging between 0% and 20%, and was determined independently in the different growth laboratories, by various methods. It is found that within the experimental uncertainty, there is no detectable bowing parameter in these alloys. This contradicts some previous experimental investigations and confirms other ones. © 1999 American Institute of Physics.
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78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
71.20.Nr Semiconductor compounds
78.20.-e Optical properties of bulk materials and thin films
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Wavelength tuning of InAs quantum dots grown on (311)B InP

S. Fréchengues, N. Bertru, V. Drouot, B. Lambert, S. Robinet, S. Loualiche, D. Lacombe, and A. Ponchet

Appl. Phys. Lett. 74, 3356 (1999); http://dx.doi.org/10.1063/1.123343 (3 pages) | Cited 48 times

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We report on the synthesis of InAs quantum dots on (311)B InP substrates. It is found that the use of such high index surfaces allows the formation of a high density (5×1010 islands/cm2) of small InAs islands (diameter≈350 Å) on InP. Moreover, a large improvement of the size uniformity is obtained in comparison with deposition on (100) surface. The standard height deviations are ±13% and ±50% for islands grown on (311)B and (100) surfaces, respectively. Then, we show that the modification of the As/P flux sequences, after the island formation, permits the control of the quantum dot emission wavelength. The achievement of quantum dots emitting at 1.55 μm at 300 K indicates that this method is promising for telecom device making. © 1999 American Institute of Physics.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Carrier-density dependence of the photoluminescence lifetimes in ZnCdSe/ZnSSe quantum wells at room temperature

C. Jordan, J. F. Donegan, J. Hegarty, B. J. Roycroft, S. Taniguchi, T. Hino, E. Kato, N. Noguchi, and A. Ishibashi

Appl. Phys. Lett. 74, 3359 (1999); http://dx.doi.org/10.1063/1.123344 (3 pages) | Cited 6 times

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Photoluminescence lifetimes have been measured at room temperature as a function of carrier density in ZnCdSe/ZnSSe quantum wells. We show that, at low carrier density (5×109–5×1010 cm−2), nonradiative recombination dominates, while radiative recombination becomes more dominant as the carrier density is increased from 5×1010 to 5×1011 cm−2. Above ∼ 5×1011 cm−2, band filling effects are shown to produce a saturation of the lifetimes. A simple rate equation model approach can be used to describe the carrier density dependence of the photoluminescence decay data obtained on a wide range of samples. A representative band-to-band recombination coefficient of 8×10−4 cm2 s−1 and a Shockley–Read–Hall rate of 7.3×107 s−1 were determined for one of the better samples studied. We believe that the excellent quality of our samples has allowed for the radiative recombination coefficient to be characterized accurately at room temperature. © 1999 American Institute of Physics.
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78.55.Et II-VI semiconductors
78.66.Hf II-VI semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths

The effect of Si doping on the defect structure of GaN/AlN/Si(111)

S. I. Molina, A. M. Sánchez, F. J. Pacheco, R. García, M. A. Sánchez-García, F. J. Sánchez, and E. Calleja

Appl. Phys. Lett. 74, 3362 (1999); http://dx.doi.org/10.1063/1.123345 (3 pages) | Cited 21 times

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The effect of Si doping on the structural quality of wurtzite GaN layers grown by molecular beam epitaxy on AlN buffered (111) Si substrates is studied. The planar defect density in the grown GaN layer strongly increases with Si doping. The dislocation density at the free surface of GaN significantly decreases when Si doping overpasses a limit value. Si doping affects the misorientation of the subgrains that constitutes the mosaic structure of GaN. The increase of the planar defect density and out-plane misorientation angles of the GaN subgrains with Si doping explain the decrease of dislocations that reach the free surface of GaN. A redshift in the photoluminescence spectra together with a decrease in the c-axis lattice parameter as the Si doping increases point to an increase in the residual biaxial tensile strain in the GaN samples. © 1999 American Institute of Physics.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
61.72.uj III-V and II-VI semiconductors
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
85.40.Ry Impurity doping, diffusion and ion implantation technology
73.20.Hb Impurity and defect levels; energy states of adsorbed species
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Disorder characterization by means of radiatively coupled quantum wells

Massimo Gurioli, Silvia Piantelli, Marcello Colocci, and Secondo Franchi

Appl. Phys. Lett. 74, 3365 (1999); http://dx.doi.org/10.1063/1.123346 (3 pages) | Cited 2 times

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We present an approach to the investigation of structural disorder in quantum wells (QWs) based on the reflectivity line shape analysis of radiatively coupled QWs. In the case of anti-Bragg structures, as a consequence of the condition of destructive interference, the reflectivity spectrum is indeed extremely sensitive to vertical disorder. We exploit the method in the case of GaAs/AlGaAs structures and we demonstrate the possibility of measuring differences in the excitonic transition energies of the two QWs as small as 10% of the inhomogeneous broadening. © 1999 American Institute of Physics.
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78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
71.35.-y Excitons and related phenomena

In situ boron incorporation and activation in silicon carbide using excimer laser recrystallization

S. D. Russell and A. D. Ramirez

Appl. Phys. Lett. 74, 3368 (1999); http://dx.doi.org/10.1063/1.123347 (3 pages) | Cited 5 times

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In situ incorporation and activation of boron into silicon carbide is demonstrated using excimer laser recrystallization in a boron trifluoride ambient. Rutherford backscattering spectroscopy and x-ray analysis demonstrate that there is no crystalline damage during recrystallization at laser fluences below ∼1.4 J/cm2. Point-contact current–voltage measurements confirm dopant activation, and the formation of shallow (∼90 nm) pn  junctions in silicon carbide. This technique may be applied to the fabrication of shallow junctions and low resistance contacts in silicon carbide power devices without ion implantation and furnace annealing. © 1999 American Institute of Physics.
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61.72.up Other materials
85.40.Ry Impurity doping, diffusion and ion implantation technology
81.05.Hd Other semiconductors
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.82.Fk Semiconductors

Molecular beam epitaxial growth of InAs/(Al, Ga)Sb quantum-well structures on germanium substrates

M. Behet, J. De Boeck, G. Borghs, and P. Mijlemans

Appl. Phys. Lett. 74, 3371 (1999); http://dx.doi.org/10.1063/1.123348 (3 pages) | Cited 2 times

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Growth of InAs/(Al, Ga)Sb quantum-well structures was performed on germanium substrates by molecular beam epitaxy. The structural and electrical quality was characterized by x-ray diffractometry, transmission electron microscopy, and Hall transport measurements. An optimization of the GaAs buffer layer growth enabled the deposition of InAs/Al0.2Ga0.8Sb quantum wells with electron mobilities of 27 500 cm2/V s at 300 K and 260 000 cm2/V s at 4.2 K. These values are comparable to those measured for identical structures grown on GaAs substrate. Our results demonstrate the feasibility of using germanium as an alternative cheap substrate instead of commonly used GaAs for the growth of InAs/Al0.2Ga0.8Sb quantum-well magnetic sensor devices. © 1999 American Institute of Physics.
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81.05.Ea III-V semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
73.61.Ey III-V semiconductors
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
85.30.Fg Bulk semiconductor and conductivity oscillation devices (including Hall effect devices, space-charge-limited devices, and Gunn effect devices)

Urbach energy dependence of the stability in amorphous silicon thin-film transistors

R. B. Wehrspohn, S. C. Deane, I. D. French, I. G. Gale, M. J. Powell, and R. Brüggemann

Appl. Phys. Lett. 74, 3374 (1999); http://dx.doi.org/10.1063/1.123349 (3 pages) | Cited 10 times

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We investigate the relationship between the stability of amorphous silicon thin-film transistors (a-Si:H TFTs) and the bulk properties of a-Si:H films. Threshold voltage shifts in a-Si:H TFTs are characterized by the thermalization energy Eth for different times and temperatures and fitted by {1+exp[(Eth−Ea)/kT0]}−2. We find that kT0 exhibits a clear correlation to the Urbach energy, but the more significant parameter Ea seems to depend only on the deposition-induced microstructure and not on the Urbach energy, the hydrogen content, or the hydrogen diffusion coefficient. © 1999 American Institute of Physics.
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85.30.Tv Field effect devices

The impact of supersaturated carbon on transient enhanced diffusion

H. Rücker, B. Heinemann, D. Bolze, R. Kurps, D. Krüger, G. Lippert, and H. J. Osten

Appl. Phys. Lett. 74, 3377 (1999); http://dx.doi.org/10.1063/1.123350 (3 pages) | Cited 15 times

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Transient enhanced diffusion of B is strongly suppressed in C-rich Si. We show that the physical mechanism for this suppression is out-diffusion of C from regions of high C concentration. B doping superlattices with background C concentrations between 1018 and 1020 cm−3 were grown by molecular beam epitaxy and implanted with BF2 ions. The measured dependence of transient B diffusion on the C profile is explained by coupled diffusion for C and Si point defects. The proposed model is supported by the observation of transient enhanced diffusion of C. © 1999 American Institute of Physics.
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66.30.J- Diffusion of impurities
61.72.uf Ge and Si
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.Yx Interaction between different crystal defects; gettering effect
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
61.72.J- Point defects and defect clusters

Electrical and structural characterization of AlxGa1−xN/GaN heterostructures grown on LiGaO2 substrates

Sangbeom Kang, William A. Doolittle, April S. Brown, and Stuart R. Stock

Appl. Phys. Lett. 74, 3380 (1999); http://dx.doi.org/10.1063/1.123351 (3 pages) | Cited 7 times

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In this letter, we report on the properties of a AlxGa1−xN/GaN heterostructure grown on LiGaO2. A two-dimensional electron gas (2DEG) is observed with mobility of 731 cm2/V s at room temperature and 2166 cm2/V s at 77 K. A comparison of the structural quality of the heterostructure as determined by x-ray diffraction shows significant improvement in comparison to a similar structure grown on a sapphire substrate. Secondary ion mass spectroscopy analysis indicates that lithium diffuses into the GaN during growth. The concentration decreases by two orders of magnitude from the substrate to the surface in a 0.8 μm thick GaN film. The enhancement of the mobility of the 2DEG compared to that of electrons in a uniformly doped film is due, in part, to the proximity of the 2DEG to the film surface, where the Li concentration is lower. In addition, we believe that the surface roughness plays a role in the mobility of the 2DEG. Despite these extrinsic factors, the good conductivity of the 2DEG shows the promise of LiGaO2 as a substrate for device-quality GaN. © 1999 American Institute of Physics.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.61.Ey III-V semiconductors
68.35.Ct Interface structure and roughness
73.50.Dn Low-field transport and mobility; piezoresistance
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.05.Ea III-V semiconductors
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