GaN Layers Grown by HVPE on P-type 6H-SiC Substrates

Gallium nitride films were successfully grown by HVPE technique on p-type 6H-SiC substrate. The layers exhibit high crystal quality as was determined by X-ray diffraction. Photoluminescence (PL) of these films was measured. The PL spectra were dominated by band edge emission. Concentration Nd-Na in undoped epitaxial layers ranged from 2×1017 to 1×1019cm−3. Mesa-structures formed by reactive ion etching showed good rectifying current-voltage characteristics for GaN/SiC pn heterojunctions.

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STRUCTURAL AND ELECTRICAL PROPERTIES OF RF MAGNETRON SPUTTERED TANTALUM OXIDE FILMS

International Journal of Nanoscience ◽

10.1142/s0219581x11008952 ◽

2011 ◽

Vol 10 (04n05) ◽

pp. 749-753

Author(s):

S. V. JAGADEESH CHANDRA ◽

D. S. PARK ◽

S. UTHANNA ◽

CHEL-JONG CHOI ◽

A. GURUVA REDDY

Keyword(s):

Tantalum Oxide ◽

Oxide Films ◽

Rf Magnetron Sputtering ◽

Silicon Substrates ◽

X Ray Diffraction ◽

X Ray ◽

Current Voltage ◽

Structural And Electrical Properties ◽

Current Voltage Characteristics ◽

P Type

RF magnetron sputtering technique was employed for deposition of tantalum oxide films on p-type silicon substrates by sputtering of pure tantalum oxide target in the presence of oxygen and argon gases at a temperature of 303 K. X-ray photoelectron spectroscopic and X-ray diffraction studies indicated that the films annealed at 773 K were stoichiometric and polycrystalline respectively. The accumulation capacitance for the devices in a structure of Al/Ta2O5/p-Si has been decreased noticeably lower values for the devices annealed at high temperatures. Improved current–voltage characteristics were observed for all annealed devices with Poole–Frenkel conduction mechanism.

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Growth and Characterization of BxGa1−xN on 6H-SiC (0001) by Movpe

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300002842 ◽

1999 ◽

Vol 4 (S1) ◽

pp. 429-434 ◽

Cited By ~ 2

Author(s):

C. H. Wei ◽

Z. Y. Xie ◽

J. H. Edgar ◽

K. C. Zeng ◽

J. Y. Lin ◽

...

Keyword(s):

Single Phase ◽

Band Edge Emission ◽

Reactant Ratio ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

Edge Emission ◽

X Ray ◽

Two Phases

Boron was incorporated into GaN in order to determine its limits of solubility, its ability of reducing the lattice constant mismatch with 6H-SiC, as well as its effects on the structural and optical properties of GaN epilayers. BxGa1−xN films were deposited on 6H-SiC (0001) substrates at 950 °C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. A single phase alloy with x=0.015 was successfully produced at a gas reactant B/Ga ratio of 0.005. Phase separation into pure GaN and BxGa1−xN alloy with x=0.30 was deposited for a B/Ga reactant ratio of 0.01. This is the highest B fraction of the wurtzite structure alloy ever reported. For B/Ga ratio ≥ 0.02, no BxGa1−xN was formed, and the solid solution contained two phases: wurtzite GaN and BN based on the results of Auger and x-ray diffraction. The band edge emission of BxGa1−xN varied from 3.451 eV for x=0 with FWHM of 39.2 meV to 3.465 eV for x=0.015 with FWHM of 35.1 meV. The narrower FWHM indicated that the quality of GaN epilayer was improved with small amount of boron incorporation.

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Growth and Characterization of BxGal-xN on 6H-SiC (0001) by MOVPE

MRS Proceedings ◽

10.1557/proc-537-g3.79 ◽

1998 ◽

Vol 537 ◽

Cited By ~ 2

Author(s):

C. H. Wei ◽

Z. Y. Xie ◽

J. H. Edgar ◽

K. C. Zeng ◽

J. Y. Lin ◽

...

Keyword(s):

Single Phase ◽

Band Edge Emission ◽

Reactant Ratio ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

Edge Emission ◽

X Ray ◽

Two Phases

AbstractBoron was incorporated into GaN in order to determine its limits of solubility, its ability of reducing the lattice constant mismatch with 6H-SiC, as well as its effects on the structural and optical properties of GaN epilayers. BxGal-xN films were deposited on 6H-SiC (0001) substrates at 950 °C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. A single phase alloy with x=0.015 was successfully produced at a gas reactant B/Ga ratio of 0.005. Phase separation into pure GaN and BxGal-xN alloy with x=0.30 was deposited for a B/Ga reactant ratio of 0.01. This is the highest B fraction of the wurtzite structure alloy ever reported. For B/Ga ratio ≥ 0.02, no BxGal-xN was formed, and the solid solution contained two phases: wurtzite GaN and BN based on the results of Auger and x-ray diffraction. The band edge emission of BxGal-xN varied from 3.451 eV for x=0 with FWHM of 39.2 meV to 3.465 eV for x=0.015 with FWHM of 35.1 meV. The narrower FWHM indicated that the quality of GaN epilayer was improved with small amount of boron incorporation.

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Electrical and Optical Characterisation of Homojjunction Gallium Nitride Light Emitting Diodes

MRS Proceedings ◽

10.1557/proc-482-1113 ◽

1997 ◽

Vol 482 ◽

Author(s):

G M Laws ◽

J Morgan ◽

G B Ren ◽

I Harrison ◽

E C Larkins ◽

...

Keyword(s):

Gallium Nitride ◽

Full Width Half Maximum ◽

Light Emitting Diodes ◽

Deep Level ◽

Deep Level Emission ◽

Near Band Edge ◽

Band Edge Emission ◽

Light Emitting ◽

Current Voltage ◽

Current Voltage Characteristics

AbstractWe report on the fabrication and characterisation gallium nitride light emitting diodes (LEDs) grown by molecular beam epitaxy on (0001) oriented sapphire and (111)B GaAs substrates. The current voltage characteristics of the devices grown on sapphire show turn on voltages of between 4 and 5V with large on-series resistance of 600Ω; for corresponding devices grown on GaAs these parameters are between 6 and 7V and 150 Ω, respectively.Room temperature electroluminescence (EL) spectra from the GaN LEDs ,grown on sapphire substrates, show a dominant emission at 3.2 eV (397nm) with a full width half maximum (FWHM) of 335 meV which is attributed to free electron to acceptor transitions (e, A−Mg). A broad low intensity deep level emission is also observed centred at 2.4 eV (506nm). The peak of the EL from the devices grown on GaAs is at 3.1eV rather than 3.2eV. The differences between the two sets of devices are probably caused by the different device geometry.Preliminary results show that an “annealing” effect caused by electrical stressing resulted in an improvement of the EL spectra. The stressed samples show an increase in the near band edge emission intensity, a 20meV reduction in the FWHM and a significant reduction in the intensity of the deep level emission. The devices have a large 1/f noise contribution which does not appear to change after electrical stressing.

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Current-voltage characteristics and X- ray diffraction study of Pd/Si1- xGex schottky contacts

Journal of Electronic Materials ◽

10.1007/bf02666627 ◽

1996 ◽

Vol 25 (3) ◽

pp. 501-505 ◽

Cited By ~ 2

Author(s):

L. He ◽

Z. Q. Shi ◽

Y. D. Zheng

Keyword(s):

Diffraction Study ◽

Schottky Contacts ◽

X Ray Diffraction ◽

X Ray ◽

Current Voltage ◽

Current Voltage Characteristics

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Al2O3 as a Transition Layer for GaN and InGaN Growth on ZnO by MOCVD

MRS Proceedings ◽

10.1557/proc-1201-h06-02 ◽

2009 ◽

Vol 1201 ◽

Author(s):

Nola Li ◽

Shen-Jie Wang ◽

William E. Fenwick ◽

Andrew Melton ◽

Chung-Lung Huang ◽

...

Keyword(s):

Room Temperature ◽

Chemical Vapor ◽

Shallow Donor ◽

Near Band Edge ◽

Band Edge Emission ◽

X Ray Diffraction ◽

Edge Emission ◽

X Ray ◽

20 Nm ◽

Related Level

AbstractGaN and InGaN layers were grown on annealed 20 and 50nm Al2O3/ZnO substrates by metalorganic chemical vapor deposition (MOCVD). GaN was only observed by high resolution x-ray diffraction (HRXRD) on 20 nm Al2O3/ZnO substrates. Room temperature photoluminescence (RT-PL) showed the red shift of the GaN near band-edge emission, which might be from oxygen incorporation forming a shallow donor-related level in GaN. HRXRD measurements revealed that (0002) InGaN layers were also successfully grown on 20nm Al2O3/ZnO substrates. In addition, thick InGaN layers (∼200-300nm) were successfully grown on Al2O3/ZnO and bare ZnO substrates. These results are significant as previous studies showed decomposition of the layer at InGaN thicknesses of 100nm or less.

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Band gap engineering, band edge emission, and p-type conductivity in wide-gap LaCuOS1−xSex oxychalcogenides

Journal of Applied Physics ◽

10.1063/1.1456240 ◽

2002 ◽

Vol 91 (7) ◽

pp. 4768-4770 ◽

Cited By ~ 78

Author(s):

Kazushige Ueda ◽

Hideo Hosono

Keyword(s):

Band Gap ◽

Band Edge ◽

Band Edge Emission ◽

Edge Emission ◽

Band Gap Engineering ◽

Type Conductivity ◽

Wide Gap ◽

P Type

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Rectifying characteristics and tunable magnetoresistance in heterojunctions of La0.9Hf0.1MnO3/0.05 wt.% Nb-doped SrTiO3

International Journal of Modern Physics B ◽

10.1142/s0217979217450229 ◽

2017 ◽

Vol 31 (25) ◽

pp. 1745022 ◽

Cited By ~ 1

Author(s):

Yaping Qi ◽

Xiangbo Liu ◽

Hao Ni ◽

Ming Zheng ◽

Liping Chen ◽

...

Keyword(s):

Band Structure ◽

Pulsed Laser ◽

Laser Deposition ◽

Ferromagnetic Transition ◽

Grown Film ◽

X Ray Diffraction ◽

Temperature Dependent ◽

X Ray ◽

Current Voltage ◽

Current Voltage Characteristics

La[Formula: see text]Hf[Formula: see text]MnO3 films were grown on 0.05 wt.% Nb-doped SrTiO3 substrates by pulsed laser deposition. X-ray diffraction measurements demonstrated that our samples were of good epitaxy and single-crystal. The temperature-dependent resistance has been investigated. It was observed that the as-grown film of La[Formula: see text]Hf[Formula: see text]MnO3 exhibited a typical paramagnetic-ferromagnetic transition. Heterojunctions of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 exhibited-asymmetric current–voltage characteristics and a remarkable temperature-dependent rectifying behavior in a wide temperature range (from 40 K to 300 K). And the most remarkable observation of this work is the existence of a crossover from positive to negative magnetoresistance in the La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction as the temperature decreases. A temperature-dependent magnetoresistance was studied as well. The rectifying characteristics and tunable magnetoresistance of these heterojunctions may be attributed to band structure of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction.

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