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105 Structural and optical properties of assynthesized, Ga2O3-coated, and Al2O3-coated GaN nanowires
Author(s): Myungil Kang, Jong-Soo Lee, Sung-Kyu Sim, Byungdon Min, Kyoungah Cho, Hyunsuk Kim, Man-Young Sung, Sangsig Kim (Affiliation: Dept. of Electr. Eng., Korea Univ., Seoul, South Korea), Se Ahn Song, Moon-Sook Lee
Journal: Thin Solid Films (Switzerland), vol.466, no.1-2, p.265-71 (1 Nov. 2004)
Publisher: Elsevier, Switzerland
Language: English
ISSN: 0040-6090, Full text
Document type: Journal article
Abstract: Structural and optical properties of as-synthesized,Ga2O3-coated, and Al2O3-coated GaN nanowires areexamined in this paper. GaN nanowires were synthesized bythermal evaporation of ball-milled GaN powders in an NH3atmosphere. The thermal annealing of the as-synthesizedGaN nanowires in an argon atmosphere allows their surfacesto be oxidized, leading to the formation of 2 nm-thick Ga2O3layers. For the oxidized GaN nanowires, the distancesbetween the neighboring lattice planes are shortened, and anexcitonic emission band is remarkably enhanced in intensity,compared with the as-synthesized GaN nanowires. Inaddition, the as-synthesized GaN nanowires were coatedcylindrically with Al2 O3 by atomic layer deposition technique.Our study suggests that the Al2O3-coating passivates some ofsurface states in the GaN nanowires (23 refs.)
Inspec No.: 8253188
106 Characterization of SnO2, In2O3, and ITO films prepared by thermal oxidation of DC-sputtered Sn, In and In-Sn films
Author(s): J.J. Valenzuela-Jauregui, R. Quintero-Gonzalez, J. Hernandez-Torres, A. Mendoza-Galvan, R. Ramirez-Bon (Affiliation: Centro de Investigacion y de Estudios, Unidad Queretaro, Mexico)
Journal: Vacuum (UK), vol.76, no.2-3, p.177-80 (5 Nov. 2004)
Publisher: Elsevier, UK
Language: English
ISSN: 0042-207X,
Full text
Document type: Journal article
Abstract: In this work, we deposited metal films of Sn, In andIn-Sn on glass substrates at room temperature by means ofthe DC sputtering technique. Films of the corresponding metaloxides were obtained after thermal annealing the metal for 1 hin air at temperatures from 350 to 500°C. We report here theproperties of the three types of metal oxides obtained by thismethod as a function of the annealing temperature. The oxidefilms were studied by X-ray diffraction, transmission andreflection spectroscopy and by measurements of their sheetresistance between coplanar electrodes. The results show thatmaterials with the properties of transparent conductive oxides(TCO) films can be obtained by this process (7 refs.)
Inspec No.: 8253261
107 The influence of ion beam bombardment on the stress of carbon layers prepared by RF magnetron sputtering
Author(s): P. Hrkut (Affiliation: Inst. of Inf., Slovak Acad. of Sci., Bratislava, Slovakia), M. Drzik, M. Mozolik, P. Kovac, S. Hascik, W. Piller, E. Platzgumer, H. Loeschner
Journal: Vacuum (UK), vol.76, no.2-3, p.329-33 (5 Nov. 2004)
Publisher: Elsevier, UK
Language: English
ISSN: 0042-207X, Full text
Document type: Journal article
Abstract: Si stencil masks covered with protective carbon layerwere tested for their resistance against ion bombardment. Theprotective layers have been created by RF carbon sputterdeposition.The openings in the structures were etched byreactive ion etching process after carbon deposition. Thevirgin as well as structured membranes were irradiated by lowenergyHe+ and Ar+ ions. We measured ion bombardmentinduced thickness- and stress-changes of the preparedsamples (5 refs.)
Inspec No.: 8253295
108 Reactivation and passivation of the Ec-0.61 eV deep level in GaN
Author(s): L. Wu, W.E. Meyer, F.D. Auret (Affiliation: Dept. of Phys., Pretoria Univ., South Africa)
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.2277-80 (2004)
Publisher: Wiley-VCH, Germany
Language: English
ISSN: 1610-1634, Full text
Document type: Conference paper in journal
Abstract: Deep level transient spectroscopy (DLTS)measurements on as-grown GaN layers on sapphiresubstrates commonly reveal three dominant traps, viz. the0.65 eV, 0.61 eV and 0.27 eV levels below the conductionband. These deep levels are normally attributed to the nativedefects that are present in the as-grown layers. We havepreviously observed that the E c-0.61 eV level behaves in analmost similar manner to bistable defects during bias-on/biasoffanneals. It is proposed that this is due to the presence of anegatively charged mobile species in the material that driftsunder the influence of an electric field and is able topassivated the Ec-0.61 eV level. Defect profiles of the levelunder zero bias and under different reverse bias conditionsshowed changes in the defect profile distributions that furtherconfirms the mobile defect/ion theory. The reactivation kineticsof the Ec -0.61 eV defect level has also been studied andresults indicate that the energy required to reactivate the levelis EReac=0.96±0.03 eV with an attempt frequency í0=6×1010±1s-1, while the reverse transformation of this level requiresEPass=0.93±0.06 eV and an attempt frequency of í 0=7×1011±1s-1 (12 refs.)
Inspec No.: 8251470
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