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1

Rare Earth Centres in Mixed Compound Crystals

100%

Kozanecki A.

Acta Physica Polonica A

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1996

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vol. 90

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issue 1

73-82

EN

A review of the Yb impurity related centres in mixed InP-based crystals has been presented. It is shown that Yb^{3+} ions can be utilized to probe alloy disorder, both in cationic (GaInP) and anionic (InPAs) alloys. The existence of alloy disorder manifested itself in the photoluminescence spectra reflecting local atomic structure of the Yb centres. The dominant emissions have been ascribed to the Yb-P_{4}Ga_{12} and Yb-P_{4}-Ga_{11}In complexes in GaInP and to Yb-P_{4} and Yb-P_{3}As centres in InPAs. The excitation and relaxation mechanisms of the 4f-shell of Yb^{3+} ions were also investigated. It was found that the temperature quenching of the Yb^{3+} luminescence was accompanied with the appearance of two thermally activated photoluminescence bands. It is suggested that photoluminescence at an energy of 25 meV below the energy gap is due to recombination of excitons bound at Yb-related centres. Relaxation of the excited 4f-shell of Yb^{3+} ions proceeds via back transfer of the excitation energy from the 4f-shell to excitons bound at Yb-centres.

2

Lattice Location of Rare Earth Ions in Semiconductors and Their Optical Activity

100%

Kozanecki A.

|

EN

Lattice location experiments performed on Yb- and Er-doped III-V semiconducting compounds using Rutherford backscattering and channeling have been reviewed. It has been shown that Yb atoms locate substitutionally in InP and InP-based ternary alloys, while in gallium compounds no substitutional fraction of Yb could be detected. An intense intra-4f-shell luminescence of Yb^{3+} has been observed in In compounds. The photoluminescence spectra of Yb^{3+} reflect local alloy disorder in InPAs and GaInP, suggesting that the Yb atoms are tetrahedrally coordinated. No Yb-related emission could be observed in gallium compounds, except a weak Yb^{3+} photoluminescence in GaP. An evidence has been presented that Er atoms introduced into III-V compounds locate predominantly at interstitial positions. In GaAs they move into tetrahedral lattice sites as a result of thermal annealing at temperatures higher than 600°C. The location of Er atoms at substitutional positions is accompanied with the disappearance of the intra-4f-shell luminescence of Er^{3+}. The reasons of the observed correlation of luminescence properties and positions of Er and Yb atoms in zincblende lattices are discussed.

3

Implantation of Rare-Earth Atoms into Si and III-V Compounds

51%

Kozanecki A., Langer J., Peaker A.

Acta Physica Polonica A

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1993

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vol. 83

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issue 1

59-70

EN

Most recent results on doping of Si and semiconductors by the implantation of rare-earth atoms are reviewed. It is shown that up to the concentration of about 1018 cm' clustering and precipitation can be avoided. Post-implantation annealing leads not only to a decrease in radiation damage, but in some cases also to migration of rare-earth implants. The results of the rare earth lattice location by the Rutherford backscattering measurements are also reported.

4

Thermally Induced Intermixing of InGaAs/GaAs Single Quantum Wells

51%

Kozanecki A., Gillin W., Sealy B.

Acta Physica Polonica A

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1993

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vol. 84

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issue 4

621-624

EN

In this work interdiffusion and strain relaxation in In_{0.2}Ga_{0.8}As/GaAs single quantum wells subjected to rapid thermal annealing have been studied using photoluminescence and Rutherford backscattering of 1.5 MeV He^{+} ions. It has been found that the diffusion coefficient of In atoms in GaAs, evaluated from the photoluminescence spectra for the assumed Gaussian well shapes, agrees within 30% with that obtained using Rutherford backscattering. Channeling angular scans, through the ⟨110⟩ axial direction of the heterostructures indicate that strain relaxation in the intermixed wells is exclusively due to compositional shallowing of the wells.

5

Excitation and Recombination Processes in InAs_{x}P_{1-x}:Yb (x=0.04, 0.07 and 0.11)

45%

Godlewski M., Kozanecki A., Karpińska K., Bergman J. P., Monemar B.

Acta Physica Polonica A

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1995

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vol. 87

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issue 1

217-220

EN

Excitation and recombination mechanisms of Yb^{3+} 4f-4f intra-shell emission in InP and InAsP (4, 7 and 11% of As) are analyzed.

6

Photoluminescence of Er^{3+} near 1.54μm in Silicon-Rich Silicon Oxide Films

45%

Kuritsyn D., Glukchanyuk V., Przybylińska H., Kozanecki A., Jantsch W.

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EN

Excitation of the intra-4f-shell luminescence near 1.5μm in silicon-rich silicon oxide is studied. Silicon-rich silicon oxide was produced by high dose implantation of Si^+ ions into SiO_2 layers grown on silicon. Erbium doping was also performed using implantation of Er^+ ions at an energy of 800 keV. An evidence is presented that transfer of energy from defects related to excess silicon in silica is the dominant mechanism of excitation of Er^{3+} for optical pumping in the UV-blue wavelength range. Si-nanocrystals created by annealing at 1100ºC rather compete for excitation with erbium than transfer energy to Er^{3+}.

7

Infrared Luminescence in Er and Er+O Implanted 6H SiC

39%

Kozanecki A., Jantsch W., Heis W., Prechtl G., Sealy B., Jeynes C.

Acta Physica Polonica A

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1997

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vol. 92

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issue 5

879-882

EN

Photoluminescence in the neighbourhood of 1.54 μm due to the ^{4}I_{13/2}-^{4}I_{15/2} intra-4f-shell transitions of Er^{3+} ions in 6H SiC is studied. Effects of oxygen coimplantation is also investigated. No difference in the photoluminescence spectra of Er only and Er+O implanted SiC was found. It is concluded that the emission around 1.54 μm in SiC:Er originates from erbium-oxygen complexes, which are formed as a result of thermal annealing.

8

Effect of Hydrostatic Pressure on InP:Yb Luminescence

39%

Stąpor A., Kozanecki A., Reimann K., Syassen K., Weber J., Moser M., Scholz F.

Acta Physica Polonica A

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1991

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vol. 79

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issue 2-3

315-318

EN

Tle effects of hydrostatic pressure on the InP:Yb luminescence were explored using a gasketed diamond anvil cell (DAC). The pressure dependence of the Yb^{3+} luminescence shows a small positive shift (0.96 meV/GPa) at low pressures (< 4 GPa) and a negative one (-0.04 meV/GPa) above 4 GPa. The spectra of the Yb^{3+} emission differ markedly in these two pressure ranges. It was concluded that intra-4f-shell transitions of the Yb^{3+} on indium substitutional (Td) site dominate in the spectrum above 4 GPa, whereas at lower pressures the emission has a different nature.

9

X-ray Study of Strain Relaxation in Heteroepitaxial AlGaAs Layers Annealed under High Hydrostatic Pressure

33%

Bąk-Misiuk J., Adamczewska J., Misiuk A., Regiński K., Wierzchowski W., Wieteska K., Kozanecki A., Kuritsyn D., Glukhanyuk W., Trela J.

Acta Physica Polonica A

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2002

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vol. 101

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issue 5

689-699

EN

The effect of treatment at up to 1270 K under hydrostatic argon pressure, up to 1.2 GPa, on strain relaxation of AlGaAs layers was investigated by X-ray diffraction and related methods. The 1.5μm thick AlGaAs layers were grown by molecular beam epitaxy method on 001 oriented semi-insulating GaAs substrate at 950 K. An increase in intensity of X-ray diffuse scattering, originating from hydrostatic pressure-induced misfit dislocations, was observed for all treated samples. For the samples treated at 920 K during 1 h under 0.6 GPa, the diffuse scattering was confined to the [110] crystallographic direction perpendicular to the direction of dislocations. For the samples treated at 1.2 GPa at the same temperature and time conditions as for 0.6G Pa, a different behaviour is observed, namely the diffuse scattering extends along all azimuthal directions, indicating that dislocations are created in both [110] and [¯110] directions. The change of strain after the treatment was most pronounced for the samples treated at 1.2 GPa for 1 h at 920 K.

Refine search results

Rare Earth Centres in Mixed Compound Crystals

Lattice Location of Rare Earth Ions in Semiconductors and Their Optical Activity

Implantation of Rare-Earth Atoms into Si and III-V Compounds

Thermally Induced Intermixing of InGaAs/GaAs Single Quantum Wells

Excitation and Recombination Processes in InAs_{x}P_{1-x}:Yb (x=0.04, 0.07 and 0.11)

Photoluminescence of Er^{3+} near 1.54μm in Silicon-Rich Silicon Oxide Films

Infrared Luminescence in Er and Er+O Implanted 6H SiC

Effect of Hydrostatic Pressure on InP:Yb Luminescence

X-ray Study of Strain Relaxation in Heteroepitaxial AlGaAs Layers Annealed under High Hydrostatic Pressure