SVIBOR - Papers quoted in CC - project code: 1-03-178

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Papers quoted in Current Contents on project 1-03-178

Quoted papers: 57
Other papers: 56
Total: 113

Title:

Authors:: Pivac, Branko (67912); Rakvin, B; Pavesi, L

Journal: J.Lumin.
ISSN: 0022-2313
Volume: 57
Year: 1993
Pages: from 227 to 229
Language: engleski
Summary: Electron spin resonance (ESR) was used to study paramagnetic defects in porous silicon. Two defects have been observed: (a) the P b0 center which exists at the interface between the pore walls and an oxidized layer (with the same asymmetry characteristic of similar defects found at the Si/SiO2 interface, and (b) dangling bonds with a symmetric line shape, which suggests the presence of an amorphous layer. Irradiation of porous silicon with gamma-rays enhanced slightly the concentration of P b0 centers but it did not introduce significant amount of E' centers as expected. This is explained with the strong interaction of E' centers with hydrogen present in material.
Keywords: silicon, porous, radiation effects

Title:

Authors:: Desnica, Dunja (9390); Ivanda, M; Kranjčec, Mladen (23323); Murri, R; Pinto, N

Journal: J. of Non-Crystalline Solids
ISSN: 0022-3093
Volume: 170
Year: 1994
Pages: from 263 to 269
Language: engleski
Summary: The influence of deposition parameters on the structure of the Gallium arsenide thin films was investigated by Raman scattering. The study was based on the analysis of the first-order Raman spectra which allows for a differentiation between amorhous component and crystallities of various sizes. The amorphous and crystalline volume fractions were calculated from the integrated intensities of the deconvoluted peaks. It was demonstrated that a transition occurs from mu-GaAs to a-GaAs for particular plasma conditions and substrate temperature. As a function of the deposition parameters the entire range from mostly microcrystalline to completely amorphous films can be optained. These properties were consistent with with the results obtained on the same samples by transmission high-energy electron diffraction and conventional transmission electron microscopy.
Keywords: GaAs, Raman, thin films,

Title:

Authors:: Kranjčec, Mladen (23323); Desnica, Dunja (9390); Čelustka, Branko (7946); Kovacs, G; Studenyak, I.P.

Journal: phys. stat. sol. (a)
ISSN: 0031-8965
Volume: 144
Year: 1994
Pages: from 223 to 233
Number of references: 20
Language: engleski
Summary: Results are given of an investigation of the absorption processes at the absorption edge of the ternary system (GaxIn1-x)2Se3 in the In-rich region. In E c polarization, the absorption coefficient for all investigated concentrations exhibits an exponential dependence on photon energy following Urbach's rule. The analysis of the results confirms that the absorption processes in the absorption edge of gamma1(GaxIn1-x)2Se3 are governed by a superposition of at least two different mechanisms, one related to the crystal phonons and the other resulting from structural and compositional disorder. The latter mechanism seems to be fundamental, influencing the absorption processes equivalently in amorphous and monocrystal states. In both E c and E c polarization an apparent dependence of absorption coefficient on sample ticknesses at constant photon energy is observed. The effect is assigned to a subsurface damage introduced by mechanical polishing.
Keywords: optical absorption, ternary compounds, III-VI,

Title:

Authors:: Pivac, Branko (67912); Tadić, T; Jakšić, M; Borghesi, A

Journal: J. Mat. Sci. Lett.
ISSN: 0261-8028
Volume: 13
Year: 1994
Pages: from 432 to 434
Language: engleski
Keywords: diffusion, Carbon, Platinum, Silicon,

Title:

Authors:: Pivac, Branko (67912); Furić, K; Milun, M; Volla, T; Borghesi, A; Sassela, A

Journal: J.Appl.Phys.
ISSN: 0021-8979
Volume: 75
Year: 1994
Pages: from 3586 to 3592
Language: engleski
Summary: Edge-defined film-fed grown polycrystalline silicon sheets, grown with one face exposed to oxidizing CO gas added to the inert Ar atmosphere, were studied. Interaction of CO with molten silicon surface during growth produced SiC-like structures in a thin layer on the surface exposed to CO. Infrared spectroscopy results suggest that this layer is constituted of good quality SiC; however, Raman and x-ray photoelectron spectroscopy showed that it consits of Si1-xCx in the form of small crystallities mixed with C- and O-rich silicon.
Keywords: pollycrystalline silicon, crystal growth, defects,

Title:

Authors:: Ivanda, M; Desnica, Uroš (9386); Haynes, T.E.; Hartman, H; Kiefer, W

Journal: J.Mol.Struct.
ISSN: 0022-2860
Volume: 348
Year: 1995
Pages: from 33 to 36
Number of references: 5
Language: engleski
Summary: Ion-induced damage in GaAs as a function of ion dose following 100 keV Si+ implants has been investigated by Raman spectroscopy. A new approach for decomposition of Raman scattering intensity on to the crystalline and amorphous phase components has been used in analysis of Raman spectra. With increasing ion dose the following was observed: a) the widths of vibrational bands of a-phase significantly increase, while the width of the LO() phonon band of c-phase remains unchanged; b) the longitudinal optical phonon of c-phase completely dissapears, while the transverse optical phonon mode evolves into a new band of a-phase; c) the vawenumbers of all vibrational bands of a- and c-phase shift to lower values by aprox. 10-15 cm-1. A number of mechanisms possibly accountable for these shifts were analysed and evaluated.
Keywords: Raman, GaAs, implantation, Si, damage, defects,

Title:

Authors:: Pavlović, Mladen; Šantić, Branko (32562); Desnica, Uroš (9386)

Journal: J. Phys. D: Appl. Phys.
ISSN: 0022-3727
Volume: 28
Year: 1995
Pages: from 934 to 938
Language: engleski
Summary: Thermally stimulated current (TSC) spectra and photocurrent (Ipc)measurements are used for determination and evaluation of deep levels, as well as for the comparison of their distributional uniformity in undoped semi-insulating (SI) GaAs crystals. Liquid-encapsulated Czochralski-grown (LEC) GaAs wafers from various sources were analysed. It was found that crystal growth and post-growth treatment of samples from each producer give characteristic and distinctive TSC spectra. The samples from different positions at wafers show good uniformity of deep-level distribution for some peoducers, whereas the uniformity is quite poor for the others. Some characteristic peaks appear in spectra of all crystals, suggesting either the presence of native defects or some of the most common contaminants. The results obtained are compared with those in previous reports. Furthermore, a considerable difference in photocurrent values after 100 s illumination has been found, indicating large free carrier lifetime scattering for samples of different origins. This study shows how, by using quick and simple TSC and Ipc measurements, the quality of the material and uniformity of the distribution of defects with deep levels in the forbidden energy gap can be assessed.
Keywords: TSC, deep levels,GaAs, semi-insulating,

Title:

Authors:: Radić, Nikola (75345); Šantić, Branko (32562); Desnica, Uroš (9386)

Journal: Jpn. J. Appl. Phys.
ISSN: 0021-4922
Year: 1995
Number of references: 18
Language: engleski
Summary: Closed-type solutions of the basic model for photoinduced metastable transformation of the EL2 centers in SI GaAs are studied. Conditions for the existence of maximum in the optical absorption alpha,photocapacitance Cd, and EPR transients are determinated. Several methods for the estimation of the initial neutral EL2 fraction (occupancy f), and cross-section for the metastable transformation sigma from the dynamics of "fingerprint" transients are proposed, and the accompanying ready-to-use monograms computed and presented.
Keywords: metastability, defects, EL2, GaAs, transients,

Title:

Authors:: Radić, Nikola (75345); Šantić, Branko (32562)

Journal: Phys. Rev. B
ISSN: 0163-1829
Volume: 51
Year: 1995
Pages: from 1117 to 1119
Number of references: 17
Language: engleski
Summary: A simple and accurate method for the determination of the sigma asterisc optical cross-section governing the EL2>EL2 transformation kinetics in GaAs is proposed. Previously reported sigma values are critically examined and corrected properly. The obtained absolute values of sigma in the 0.9-1.35eV photon energy range all falling onto the same universal curve as presented. The sigma(Eph) curve exhibits a maximum amounting to aprox. 4 10Č17 cmČ2 at 1.18 eV, and it drops below 10Č-20 cmČ2 for photon energies less than 0.95 eV
Keywords: metastability, EL2, defects, GaAs, optical cross-section,

Title:

Authors:: Gracin, Davor (82826); Radić, Nikola (75345); Desnica, Uroš (9386)

Journal: Vacuum
ISSN: 0042-207x
Volume: 46
Year: 1995
Pages: from 943 to 946
Number of references: 19
Language: engleski
Summary: The a-Si:H, a-Si1-xCx:H and a-Si1-yNy:H alloys were deposited by dc magnetron sputtering and their microstructural properties were examined as a function of hydrogen (5-30 at%), carbon (x=0-0.4) and nitrogen (y=0-0.3) content. The sample density and void volume distribution in deposited alloys were estimated by IR and NIR spectroscopy. It has been found that the total void volume contribution increases, the void size distribution broadens and its mean value increases as the concentration of each alloying element increases.
Keywords: amorphous, silicon, silicon alloys, microstructural properties,

Title:

Authors:: Pivac, Branko (67912); Rakvin, B; Pavesi, L

Journal: Appl.Phys.Lett.
Number: 25
ISSN: 0003-6951
Volume: 65
Year: 1994
Pages: from 3260 to 3262
Number of references: 22
Language: engleski
Summary: Formation of paramagnetic centers in aged porous silicon samples is studied by electron paramagnetic resonance. Samples oxidized by aging in air at room temperature exhibit the P b centers as dominant defects. These are formed at the interfaces between the Si nanocrystallities and the amorphous SiOx layer into which the nanocrystallities are ebbedded and which is formed during the aging. No other paramagnetic centers, such as the E' center that is characteristic of thin SiO2 layers on Si, are observed. This finding is explained by the hydrogen passivisation of E' centers in oxygen-rich porous structures and by instability of the E'center near the interface. The P b center is stable after gamma irradiation.

Title:

Authors:: Borghesi, A; Pivac, Branko (67912); Sassela, A; Stella, A

Journal: J.Appl.Phys.
Number: 9
ISSN: 0021-8979
Volume: 77
Year: 1995
Pages: from 4169 to 4244
Number of references: 445
Language: engleski
Summary: A review is presented of the recent advances in the study of oxygen precipitation and of the main properties of oxide precipitates in silicon. After a general overview of the system "oxygen in silicon", the thermodinamics and the kinetcs of the precipitate formation are treated in detail, with major emphasis on the phenomenology; subsequently, the most important techniques for the characterization of the precipitates are illustrated together with the most interesting and recent results. Finally, the possible influence of oxygen precipitation on technological applications is stressed, with particular attention to recent results regarding device yield. Actually, the essential novelty of this review rests on the attempt to give an extended picture of what has been recently clarified by means of highly sophisticated dignostic methods and of the influence of precipitation on the properties of semiconductor devices.

Title:

Authors:: Sassela, A; Pivac, Branko (67912); Abe, T; Borghesi, A

Journal: Materials Sci. & Eng. B
ISSN: 0025-5416
Year: 1995
Number of references: 8
Language: engleski
Summary: Infrared absorption spectra of very thin SiO2 films embedde in silicon are reported and analyzed. From these results a new interpretation of the characteristic absorption band of platelet precipitates in silicon can be proposed, based on the excitation of surface modes. On this basis, the quantitative evaluation of precipitated oxygen is demonstrated to be unreliable.

Title:

Authors:: Pivac, Branko (67912); Sassela, A; Borghesi, A

Journal: Mat. Sci. and Eng. B
ISSN: 0025-5416
Year: 1995
Number of references: 62
Language: engleski
Summary: The impurities present in silicon for solar cells directly influence its electrical characteristics and therefore solar cells performance. Light non-doping impurities like oxygen, carbon, hydrogen and nitrogen are of particular importance since they exhibit both a positive and a negative impact when present in silicon substrates. In this overview we illustrate the positive and negative effects of impurities on silicon material properties. It is also shown that their cotemporary presence leads to a mutual interaction and hence to the formation of more complex structures.
Keywords: Silicon, Solar cells

Title:

Authors:: Pivac, Branko (67912); Tadić, T; Jakšić, M

Journal: J. Mat. Sci. Lett.
ISSN: 0261-8028
Volume: 13
Year: 1994
Pages: from 432 to 434
Number of references: 10
Language: engleski


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