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113 Organized molecular assemblies: creation and investigation of their functional properties
Author(s): S.M. Repinsky (Affiliation: Inst. of Semicond. Phys., SB RAS, Novosibirsk, Russia)
Journal: e-J. Surf. Sci. Nanotechnol. (Japan), vol.1 (2003)
Publisher: Surface Sci. Soc. Japan, Japan
Language: English
ISSN: 0000-0957
Document type: Journal article
Abstract: It has been discussed the notion of an organizedmolecular assemblies as the key problem of the lowdimensionsystems physics and the supramolecular chemistry.An organized molecular assembly is a group of atoms ormolecules built in a solid matrix due to chemical orintermolecular interactions and possessing, in total, the abilityto produce a definite response to the given perturbation. Theeffectiveness of this approach has been shown on examplesthe search for systems that evolve to the formation of twodimensional organized molecular assemblies at the boundarybetween a semiconductor crystal and a dielectric and alsocreating quantum dots and chemical sensors (45 refs.)
Inspec No.: 8250141
114 Top most surface studies by total reflection positron diffraction
Author(s): A. Kawasuso, T. Ishimoto, Y. Fukaya, K. Hayashi (Affiliation: Adv. Sci. Res. Center, Japan Atomic Energy Res. Inst., Gunma, Japan), A. Ichimiya
Journal: e-J. Surf. Sci. Nanotechnol. (Japan), vol.1 (2003)
Publisher: Surface Sci. Soc. Japan, Japan
Language: English
ISSN: 0000-0957, Full text
Document type: Journal article
Abstract: In this article, we describe in detail the developmentand application of reflection high-energy positron diffraction(RHEPD). A fine positron beam with a coherence length ofapproximately 170 â was obtained by the electrostatic lenssystem. The beam quality is good enough to observe theRHEPD patterns from a clean Si(111)7×7 and SiC(0001)surfaces. The rocking curve associated with the Si(111)7×7surface revealed the fact that the vertical position of theadatom layer relative to the first layer is sufficiently relaxedtowards the vacuum region than that expected from theelectron diffraction experiments. After the high temperaturehydrogen etching, the SiC surface became atomically smooth.It was found that Si face is somewhat unstable to the oxygenadsorption as compared to C face. The rocking curves werereproduced assuming the attachment of oxygen atoms at T1site with a bond length of 1.88â. Heating the SiC surface inthe ultra-high vacuum after the sacrificial oxidation andhydrofluoric etching, an atomically flat carbon rich surfaceappeared (21 refs.)
Inspec No.: 8250148
115 Hydrogen passivation kinetics of Si nanocrystals in SiO2
Author(s): A.R. Wilkinson, R.G. Elliman (Affiliation: Res. Sch. of Phys. Sci. & Eng., Australian Nat. Univ., Canberra, ACT, Australia)
Editor(s): T.Gregorkiewicz, R.G.Elliman, P.M.Fauchet, J.A. Hutchby
Conference: Optoelectronics of Group-IV-Based Materials Symposium, San Francisco, CA, USA
Conference Date: 21-24 April 2003
Sponsor(s): Army Res. Office
Publication: Optoelectronics of Group-IV-Based Materials Symposium (Mater. Res. Soc. Symposium Proceedings Vol.770)
Publisher: Mater. Res. Soc, USA, 2003
Language: English
ISBN: 1 55899 707 5 Page: 81-6
Document type: Conference paper
Abstract: Hydrogen passivation of non-radiative defectsincreases the luminescence intensity from siliconnanocrystals. In this study, photoluminescence (PL) and timeresolvedPL were used to investigate the chemical kinetics ofthe hydrogen passivation process. Isochronal and isothermalannealing sequences were used to determine the reactionkinetics for the absorption and desorption of hydrogen, usingthe generalised consistent simple thermal (GST) modelproposed by Stesmans for Pb defects at planar Si/SiO2interfaces. This included determination of the activationenergies and rate constants for the forward and reversereactions as well as the associated spread in activationenergies. The reaction kinetics determined from suchmeasurements were found to be in excellent agreement withthose for the passivation of Pb defects at planar Si/SiO2interfaces, suggesting the nanocrystal emission process isalso limited by such defects. These results provide usefulmodel data as well as insight into the processing conditionsneeded to achieve optimum passivation in H2. As an extensionto the work, a preliminary study into passivation by atomichydrogen was pursued via a post-metallization Al anneal(alneal). A considerable gain in luminescence efficiency wasachieved over the previously optimised passivation in H2 (16refs.)
Inspec No.: 8253409
116 Oxidation of Si/nc-Ge/Si heterostructures for non volatile memory applications
Author(s): M. Kanoun, A. Souifi, S. Decossas, C. Dubois, G. Bremond (Affiliation: Lab. de Phys. de La Matiere, UMRCNRS, Villeurbanne, France), F. Bassani, Y. Lim, A. Ronda, I. Berbezier, O. Kermarrec, D. Bensahel
Editor(s): O.D.Velev, T.J.Bunning, Y.Xia, P.Yang
Conference: Unconventional Approaches to Nanostructures with Applications in Electronics, Photonics, Information Storage and Sensing Symposium, San Francisco, CA, USA
Conference Date: 21-25 April 2003
Publication: Unconventional Approaches to Nanostructures with Applications in Electronics, Photonics, Information Storage and Sensing Symposium (Mater. Res. Soc. Symposium Proceedings Vol.776)
Publisher: Mater. Res. Soc, USA, 2003
Language: English
ISBN: 1 55899 713 X Page: 253-8
Document type: Conference paper
Abstract: In this work, we present an extensive study of theoxidation process of Si/Ge nanocrystals (nc-Ge)/Si samplesusing SIMS (second ion mass spectroscopy), transmissionelectron microscopy (TEM), atomic force microscopy (AFM)and electrical characterization of metal/oxide/semiconductorcapacitors (MOS). Various samples with different oxidationtimes have been studied and it is demonstrated that silicon dryoxidation kinetics is not influenced by the presence of Ge. Asshown by SIMS measurements, a pure SiO2 layer is formedon the top of the structure, while the Ge atoms are intermixedwith the silicon substrate. The TEM and AFM analysis showthat the nc-Ge height is drastically reduced during theoxidation process. The fabrication of MOS capacitors on thestructures allowed to study electron and hole trapping in theGe dots. From our analysis we have shown that the Genanostructures which covered by SiO2 are not isolated fromthe Si substrate (11 refs.)
Inspec No.: 8253457
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