Bowing Parameter of AlxGa1-xN

2002 ◽  
Vol 722 ◽  
Author(s):  
Feng Yun ◽  
Michael A. Reshchikov ◽  
Lei He ◽  
Thomas King ◽  
M. Zafar Iqbal ◽  
...  
Keyword(s):  
Entire Range ◽  
Rutherford Backscattering Spectrometry ◽  
Parameter Determination ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sapphire Substrates ◽  
Bowing Parameter ◽  
Large Dispersion ◽  
Parameter Values ◽  
Secondary Ion

AbstractAlxGa1-xN samples covering the entire range of alloy compositions, 0≤x≤1, were grown by plasma-assisted MBE on c-plane sapphire substrates. The aluminum mole fraction was determined, by three different techniques, namely, x-ray diffraction, secondary ion mass spectroscopy, and Rutherford backscattering spectrometry. The energy bandgaps of the alloys were obtained from low temperature reflectance spectra. The data lead to a bowing parameter of b=1.0 eV in relating the bandgap of the AlxGa1-xN alloy to its chemical composition. A discussion of bowing parameter determination is presented along with possible causes for the large dispersion in previously reported bowing parameter values.

Implantation and Activation of High Concentrations of Boron and Phosphorus in Germanium

2005 ◽  
Vol 891 ◽  
Author(s):  
Yong Seok Suh ◽  
Malcolm S. Carroll ◽  
Roland A. Levy ◽  
Gabriele Bisognin ◽  
Davide De Salvador ◽  
...  
Keyword(s):  
Peak Concentration ◽  
Secondary Ion Mass Spectrometry ◽  
Rutherford Backscattering Spectrometry ◽  
Nuclear Reaction Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Concentrations ◽  
X Ray Absorption ◽  
Secondary Ion ◽  
Activation Behavior

ABSTRACTThe effect of increasing boron or phosphorus implant dose (i.e., 5×1013-5×1016 cm−2) and subsequent annealing (400-600°C for 3 hrs in N2) on the activation, diffusion and structure of germanium is studied in this work. The peak concentration of implant dose is ∼ 2×1021 cm−3. Secondary ion mass spectrometry (SIMS), spreading resistance profiling (SRP), high resolution X-ray diffraction (HRXRD), X-ray absorption fine structure (XAFS), Rutherford backscattering spectrometry (RBS), and nuclear reaction analysis (NRA) were used to characterize the implant and activation behavior. Boron is found to have a high solid solubility (i.e., > 2×1020 cm−3), even immediately after implant; while in contrast, phosphorus is limited to ∼ 1–2×1019 cm−3. Diffusion of phosphorus is also extremely extrinsic, while boron is practically immobile.

scholarly journals The impact of point defects in n-type GaN layers on thermal decomposition of InGaN/GaN QWs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mikolaj Grabowski ◽  
Ewa Grzanka ◽  
Szymon Grzanka ◽  
Artur Lachowski ◽  
Julita Smalc-Koziorowska ◽  
...  
Keyword(s):  
Quantum Wells ◽  
High Temperatures ◽  
Point Defects ◽  
X Ray Diffraction ◽  
Helium Ions ◽  
X Ray ◽  
Sapphire Substrates ◽  
Transmission Electron ◽  
The Impact ◽  
Ingan Quantum Wells

AbstractThe aim of this paper is to give an experimental evidence that point defects (most probably gallium vacancies) induce decomposition of InGaN quantum wells (QWs) at high temperatures. In the experiment performed, we implanted GaN:Si/sapphire substrates with helium ions in order to introduce a high density of point defects. Then, we grew InGaN QWs on such substrates at temperature of 730 °C, what caused elimination of most (but not all) of the implantation-induced point defects expanding the crystal lattice. The InGaN QWs were almost identical to those grown on unimplanted GaN substrates. In the next step of the experiment, we annealed samples grown on unimplanted and implanted GaN at temperatures of 900 °C, 920 °C and 940 °C for half an hour. The samples were examined using Photoluminescence, X-ray Diffraction and Transmission Electron Microscopy. We found out that the decomposition of InGaN QWs started at lower temperatures for the samples grown on the implanted GaN substrates what provides a strong experimental support that point defects play important role in InGaN decomposition at high temperatures.

Problems Associated with Kα Doublet in Residual Stress Measurements

1979 ◽  
Vol 23 ◽  
pp. 333-339
Author(s):  
S. K. Gupta ◽  
B. D. Cullity
Keyword(s):  
Residual Stress ◽  
Silicon Powder ◽  
Lattice Parameter ◽  
Diffraction Peak ◽  
Parameter Determination ◽  
X Ray Diffraction ◽  
X Ray ◽  
Analysis Techniques ◽  
The Difference ◽  
Similar Accuracy

Since the measurement of residual stress by X-ray diffraction techniques is dependent on the difference in angle of a diffraction peak maximum when the sample is examined consecutively with its surface at two different angles to the diffracting planes, it is important that these diffraction angles be obtained precisely, preferably with an accuracy of ± 0.01 deg. 2θ. Similar accuracy is desired in precise lattice parameter determination. In such measurements, it is imperative that the diffractometer be well-aligned. It is in the context of diffractometer alignment with the aid of a silicon powder standard free of residual stress that the diffraction peak analysis techniques described here have been developed, preparatory to residual stress determinations.

scholarly journals MOVPE Growth of Quaternary (Al,Ga,In)N for UV Optoelectronics

2000 ◽  
Vol 5 (S1) ◽  
pp. 412-424
Author(s):  
Jung Han ◽  
Jeffrey J. Figiel ◽  
Gary A. Petersen ◽  
Samuel M. Myers ◽  
Mary H. Crawford ◽  
...  
Keyword(s):  
Room Temperature ◽  
Rutherford Backscattering Spectrometry ◽  
Optoelectronic Devices ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Energy ◽  
Movpe Growth ◽  
Pl Emission

We report the growth and characterization of quaternary AlGaInN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices.

Properties of Sputter Deposited ZnO Films Co-doped with Lithium and Phosphorus

2013 ◽  
Vol 1494 ◽  
pp. 77-82
Author(s):  
T. N. Oder ◽  
A. Smith ◽  
M. Freeman ◽  
M. McMaster ◽  
B. Cai ◽  
...  
Keyword(s):  
Rf Magnetron Sputtering ◽  
Zno Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sapphire Substrates ◽  
Hall Effect Measurements ◽  
Sputter Deposited ◽  
P Type ◽  
Post Deposition ◽  
Co Doped

ABSTRACTThin films of ZnO co-doped with lithium and phosphorus were deposited on sapphire substrates by RF magnetron sputtering. The films were sequentially deposited from ultra pure ZnO and Li3PO4 solid targets. Post deposition annealing was carried using a rapid thermal processor in O2 and N2 at temperatures ranging from 500 °C to 1000 °C for 3 min. Analyses performed using low temperature photoluminescence spectroscopy measurements reveal luminescence peaks at 3.359, 3.306, 3.245 eV for the co-doped samples. The x-ray diffraction 2θ-scans for all the films showed a single peak at about 34.4° with full width at half maximum of about 0.17°. Hall Effect measurements revealed conductivities that change from p-type to n-type over time.

Chromium implantation in silica glass

1996 ◽  
Vol 11 (1) ◽  
pp. 229-235 ◽  
Author(s):  
E. Cattaruzza ◽  
R. Bertoncello ◽  
F. Trivillin ◽  
P. Mazzoldi ◽  
G. Battaglin ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Photoelectron Spectroscopy ◽  
Silica Glass ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Secondary Ion Mass Spectrometry ◽  
Rutherford Backscattering Spectrometry ◽  
X Ray ◽  
Chromium Silicide ◽  
Secondary Ion

Silica glass was implanted with chromium at the energy of 35 and 160 keV and at fluences varying from 1 × 1016 to 11 × 1016 ions cm−2. In a set of chromium-implanted samples significant amounts of carbon were detected. Samples were characterized by x-ray photoelectron spectroscopy, x-ray-excited Auger electron spectroscopy, secondary ion mass spectrometry, and Rutherford backscattering spectrometry. Chromium silicide and chromium oxide compounds were observed; the presence of carbon in the implanted layers induces the further formation of chromium carbide species. Thermodynamic considerations applied to the investigated systems supply indications in agreement with the experimental evidences.

Ti-doped Gallium Phosphide Layers with Concentrations Above the Mott Limit

2009 ◽  
Vol 1210 ◽  
Author(s):  
Javier Olea Ariza ◽  
David Pastor ◽  
María Toledano-Luque ◽  
Ignacio Mártil ◽  
Germán González-Díaz ◽  
...  
Keyword(s):  
Gallium Phosphide ◽  
Vibrational Mode ◽  
Pulsed Laser ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
Intermediate Band ◽  
X Ray ◽  
Tof Sims ◽  
Crystalline Domains ◽  
Secondary Ion

AbstractWe have studied the Pulsed-Laser Melting (PLM) effects on Ti implanted GaP to form an Intermediate Band (IB). Structural analysis has been carried out by means of Time of Flight Secondary Ion Mass Spectroscopy (ToF-SIMS), Raman spectroscopy and Glancing Incidence X-Ray Diffraction (GIXRD). After the PLM annealing, Ti concentration is over the Mott limit. Nevertheless, the Raman spectra show a forbidden TO vibrational mode of GaP. This result suggests the formation of crystalline domains with a different orientation in the annealed region regarding to the GaP unannealed substrate. This conclusion has been corroborated by GIXRD measurements. As a result of the polycrystalline lattice, a drop of the mobility is produced.

Yttrium Implantation and Manganese Addition Element Effects on the High Temperature Oxidation Resistance of a Model Steel

2008 ◽  
Vol 595-598 ◽  
pp. 897-905
Author(s):  
Eric Caudron ◽  
Régis Cueff ◽  
Christophe Issartel ◽  
N. Karimi ◽  
Frédéric Riffard ◽  
...  
Keyword(s):  
Oxidation Resistance ◽  
High Temperatures ◽  
Mixed Oxides ◽  
Rutherford Backscattering Spectrometry ◽  
High Energy ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
X Ray ◽  
Steel Oxidation ◽  
Yttrium Implantation

Manganese addition and subsequent yttrium implantation effects on extra low carbon steel were studied by Rutherford Backscattering Spectrometry (RBS), Reflection High Energy Electron Diffraction (RHEED), X-ray Diffraction (XRD) and Glancing Angle X-ray Diffraction (GAXRD). Thermogravimetry and in situ X-Ray Diffraction at 700°C and PO2=0.04 Pa for 24h were used to determine the manganese alloying addition and subsequent yttrium implantation effects on reference steel oxidation resistance at high temperatures. This study clearly shows the combined effect of manganese alloying addition and subsequent yttrium implantation which promotes the formation of several yttrium mixed oxides seem to be responsible for the improved reference steel oxidation resistance at high temperatures.

AlxGa1-xN-Based Materials and Heterostructures

1996 ◽  
Vol 449 ◽  
Author(s):  
P. Kung ◽  
A. Saxler ◽  
D. Walker ◽  
X. Zhang ◽  
R. Lavado ◽  
...  
Keyword(s):  
Chemical Vapor ◽  
Bragg Reflectors ◽  
X Ray Diffraction ◽  
Chemical Vapor Deposition Growth ◽  
X Ray ◽  
Sapphire Substrates ◽  
Transmission Electron ◽  
Dimensional Electron Gas ◽  
P Type

ABSTRACTWe present the metalorganic chemical vapor deposition growth, n-type and p-type doping and characterization of AlxGa1-xN alloys on sapphire substrates. We report the fabrication of Bragg reflectors and the demonstration of two dimensional electron gas structures using AlxGa1-xN high quality films. We report the structural characterization of the AlxGa1-xN / GaN multilayer structures and superlattices through X-ray diffraction and transmission electron microscopy. A density of screw and mixed threading dislocations as low as 107 cm-2 was estimated in AlxGa1-xN / GaN structures. The realization of AlxGa1-xN based UV photodetectors with tailored cut-off wavelengths from 365 to 200 nm are presented.

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