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76 Effect of high-frequency electromagnetic field on Te+-implanted (001) Si
Author(s): M. Kalitzova, E. Vlakhov, Y. Marinov (Affiliation: Inst. of Solid State Phys., Bulgarian Acad. of Sci., Sofia, Bulgaria), K. Gesheva, V. Ignatova, O. Lebedev, C. Muntele, R. Gijbels
Journal: Vacuum (UK), vol.76, no.2-3, p.325-8 (5 Nov. 2004)
Publisher: Elsevier, UK
Language: English
ISSN: 0042-207X, Full text
Document type: Journal article
Abstract: The analysis of high-frequency electromagnetic field (HFEMF) effects on the microstructure and electrical properties of Te+ implanted (001) Si is reported. Crosssectional high-resolution transmission electron microscopy (XHRTEM) demonstrates the formation of Te nanoclusters (NCs) embedded in the Si layer amorphized by implantation (a-Si) at fluences ges1×1016 cm-2. Post-implantation treatment with 0.45 MHz HFEMF leads to enlargement of Te NCs, their diffusion and accumulation at the a-Si surface and formation of laterally connected extended tellurium structures above the percolation threshold, appearing at an ion fluence of 1×1017 cm-2. AC electrical conductivity measurements show nearly four orders of magnitude decrease of impedance resistivity in this case, which is in good agreement with the results of our structural studies. The results obtained are discussed in terms of the two-phase isotropic spinodal structure (9 refs.)
Inspec No.: 8253294
77 Damage formation and annealing in InP due to swift heavy ions
Author(s): A. Kamarou, W. Wesch, E. Wendler (Affiliation: Inst. fur Festkorperphys., Friedrich-Schiller-Univ., Jena, Germany), S. Klaumunzer
Conference: TRACKS03 'The Evolution of Ion Tracks in Matter - from the Initial Excitation to Columnar Nano Structures' Summer School, Muhlhausen, Germany
Conference Date: 8-15 Sept. 2004
Journal: Nucl. Instrum. Methods Phys. Res. B, Beam Interact. Mater. At. (Netherlands), vol.225, no.1-2, p.129-35 (Aug. 2004)
Publisher: Elsevier, Netherlands
Language: English
ISSN: 0168-583X, Full text
Document type: Conference paper in journal
Abstract: Virgin and pre-damaged InP samples were irradiated at room temperature (RT) and at liquid nitrogen temperature (LNT) with different fluences of 140 MeV Kr, 390 MeV Xe and 600 MeV Au ions. The pre-damaging was performed with 600 keV Ge ions at LNT to obtain different damage levels. The samples were analysed by means of Rutherford backscattering spectrometry (RBS) in random and channelling geometry. A relatively weak damage accumulation in virgin InP and a very significant defect annealing in pre-damaged InP occurs due to 140 MeV Kr irradiation. The damaging of virgin InP with 390 MeV Xe and 600 MeV Au is much more efficient in comparison with that of 140 MeV Kr. Further, annealing of the pre-damaged InP due to 390 MeV Xe irradiation is hardly visible. At LNT, InP appears to be much more radiation-resistant to swift heavy ion (SHI) irradiation than at RT. Our results show that during SHI irradiation of InP, both damage formation and damage annealing occur simultaneously. Whether the first or the second one plays a more important role depends on the SHI mass and energy (11 refs.)
Inspec No.: 8249332
78 Defects and diffusion in high purity silicon for detector applications
Author(s): B.G. Svensson, E.V. Monakhov, G. Alfieri, M. Mikelsen (Affiliation: Dept. of Phys., Oslo Univ., Norway), B.S. Avset, A. Hallen
Conference: Conference on Photo-responsive Materials, Eastern Cape, South Africa
Conference Date: 25-29 Feb. 2004
Sponsor(s): EMF Ltd. (UK); Sensors Unlimited Inc. (USA); Carl Zeiss (Pty) Ltd
Journal: Phys. Status Solidi C (Germany), no.9, p.2250-7 (2004)
Publisher: Wiley-VCH, Germany
Language: English
ISSN: 1610-1634, Full text
Document type: Conference paper in journal
Abstract: In this contribution we review some recent results on defects occurring after irradiation and thermal treatment of silicon detectors for ionizing radiation. In particular, the annealing of the prominent divacancy centre and the concurrent growth of a new double acceptor centre, assigned to the divacancy-oxygen pair, is treated in detail. The detectors were fabricated using oxygenated high purity float zone (FZ) silicon wafers of n-type in order to improve the radiation hardness. The results obtained have important implication on our current understanding of the degradation of silicon detectors at high radiation fluences and suggest that a new concept for optimised impurity/defect engineering needs to be developed (31 refs.)
Inspec No.: 8251473
79 On the nature of Si-doping in AlGaN alloys
Author(s): M.C. Wagener, G.R. James, A.W.R. Leitch (Affiliation: Dept. of Phys., Port Elizabeth Univ., South Africa), F. Omnes
Conference: Conference on Photo-responsive Materials, Eastern Cape, South Africa
Conference Date: 25-29 Feb. 2004
Sponsor(s): EMF Ltd. (UK); Sensors Unlimited Inc. (USA); Carl Zeiss (Pty) Ltd
Journal: Phys. Status Solidi C (Germany), no.9, p.2322-7 (2004)
Publisher: Wiley-VCH, Germany
Language: English
ISSN: 1610-1634, Full text
Document type: Conference paper in journal
Abstract: The silicon doping characteristics of AlxGa1-x N were investigated over the x=0.2-0.5 composition range. A combination of Hall effect, thermal admittance and variable temperature photoluminescence spectroscopy indicated that the Si donor level maintained a near effective-mass state behaviour over the composition range studied. Alloy fluctuations appeared to influence the Si donor level, with the activation energies increasing more steeply with increasing compositions than predicted for an effective-mass like donor. Although, the Si donor state was localised to some degree within the band gap, the transformation into a DX-centre appeared to be suppressed for these compositions (13 refs.)
Inspec No.: 8251478
80 Impact of bulk reduction on TiO2(100)/K
Author(s): R. Lindsay, E. Michelangeli, B.G. Daniels (Affiliation: Dept. of Chem., Manchester Univ., UK), M. Polcik, A. Verdini, L. Floreano, A. Morgante, G. Thornton
Conference: 22nd European Conference on Surface Science, Prague, Czech Republic
Conference Date: 7-12 Sept. 2003
Journal: Surf. Sci. (Netherlands), vol.566-568, pt.2, p.921-5 (20 Sept. 2004)
Publisher: Elsevier, Netherlands
Language: English
ISSN: 0039-6028, Full text
Document type: Conference paper in journal
Abstract: Photoelectron spectroscopy, low energy electron diffraction, and reflection high energy electron diffraction have been employed to probe the electronic and geometric structure of the TiO2(100)/K interface. Data have been obtained from two (100) oriented single crystal samples, which differ in their extent of bulk reduction. It is demonstrated that this parameter is important for both the electronic and geometric structure of ordered TiO2(100)/K surfaces, formed by annealing to ~1000 K. Photoelectron spectra, recorded following this preparation, indicate that reduced Ti states are present for the less stoichiometric sample, which exhibits a (1 - 1 2 2) surface unit cell. In contrast, the other sample displays a c(2×2) overlayer, with no Ti reduction evidenced (12 refs.)
Inspec No.: 8253054
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