Nano-Scale Native Oxide on 6H-SiC Surface and its Effect on the Ni/Native Oxide/SiC Interface Band Bending

Native oxide layer with thickness of about 1 nm was found easy to form on 6H-SiC surface during transporting from cleaning process to vacuum chambers, which was examined by x-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). The interface band bending was studied by synchrotron radiation photoelectron spectroscopy (SRPES). For the native-oxide/SiC surface, after Ni deposition, the binding energy of Si 2p red-shifted about 0.34 eV, which suggested the upward bending of the interface energy band. Therefore, the native oxide layer should be considered on the study of SiC devices because it may affect the electron transport properties significantly.

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Magnetic and Structural Characterization of Mechanically Alloyed Fe50co50 Samples

Revista de Ciencias ◽

10.25100/rc.v15i0.516 ◽

2012 ◽

Vol 15 ◽

pp. 41-47

Author(s):

Germán A. Pérez Alcázar ◽

Ligia Edith Zamora ◽

José Francisco Marco ◽

Juan José Romero ◽

Jesús María González ◽

...

Keyword(s):

Oxide Layer ◽

Field Distribution ◽

Photoelectron Spectroscopy ◽

Hyperfine Magnetic Field ◽

Complete Removal ◽

Milling Process ◽

Native Oxide ◽

Nominal Composition ◽

Native Oxide Layer ◽

X Ray

Samples of nominal composition Fe50Co50 were produced by mechanical alloying byusing a planetary ball mill and different milling times. The samples were studied via X-raydiffraction, Mössbauer spectroscopy, and X-ray photoelectron spectroscopy to characterize thephase distribution resulting from the milling process. The Mössbauer data indicated that Co startsdiffusing into Fe after 8 h of milling. Between t = 8h and t = 24 h the sample has a heterogeneouscomposition, presenting a bimodal hyperfine field distribution with maxima centred at 34.3 T and35.8 - 36.4 T, compatible with the presence of different Fe environments (richer in Co and richerin Fe, respectively). After 48 h of milling, the sample presents a more homogeneous compositionshowing an almost symmetric hyperfine magnetic field distribution centred at H=34.9 T,indicating that a disordered equiatomic FeCo solid solution has already been formed. The X-rayphotoelectron spectroscopy data indicate that the native oxide layer formed on the freshly milledsamples contains Co2+, Fe2+ and Fe3+ oxides. After complete removal of this native oxide layer byAr ion bombardment, X-ray photoelectron spectroscopy analysis yields the composition of thenominal equiatomic Fe50Co50 alloy.

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The Effect of Surface States on Secondary Electron (SE) Dopant Contrast from Silicon p-n Junctions

MRS Proceedings ◽

10.1557/proc-1026-c04-02 ◽

2007 ◽

Vol 1026 ◽

Author(s):

Augustus K. W. Chee ◽

Conny Rodenburg ◽

Colin John Humphreys

Keyword(s):

Oxide Layer ◽

Computer Modelling ◽

Surface States ◽

Native Oxide ◽

Native Oxide Layer ◽

Element Analysis ◽

Surface Band ◽

Band Bending ◽

Wide Range ◽

Se Doping

AbstractDetailed computer modelling using finite-element analysis was performed for Si p-n junctions to investigate the effects of surface states and doping concentrations on surface band-bending, surface junction potentials and external patch fields. The density of surface states was determined for our Si specimens with a native oxide layer. Our calculations show that for a typical density of surface states for a Si specimen with a native oxide layer, the effects of external patch fields are negligible and the SE doping contrast is due to the built-in voltage across the p-n junction modified by surface band-bending. There is a good agreement between the experimental doping contrast and the calculated junction potential just below the surface, taking into account surface states, for a wide range of doping concentrations.

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Эволюция физико-химических свойств поверхности GaSb(100) в растворах сульфида аммония

Физика и техника полупроводников ◽

10.21883/ftp.2019.07.47866.9070 ◽

2019 ◽

Vol 53 (7) ◽

pp. 908

Author(s):

М.В. Лебедев ◽

Т.В. Львова ◽

А.Л. Шахмин ◽

О.В. Рахимова ◽

П.А. Дементьев ◽

...

Keyword(s):

Oxide Layer ◽

Photoelectron Spectroscopy ◽

Treatment Time ◽

Solution Concentration ◽

Native Oxide ◽

Semiconductor Surface ◽

Native Oxide Layer ◽

Force Microscopy ◽

Fermi Level Pinning ◽

Ammonium Sulfide

AbstractVarious conditions of passivation of the GaSb(100) surface by ammonium sulfide ((NH_4)_2S) solutions depending on the solution concentration, solvent, and treatment time are investigated by X-ray photoelectron spectroscopy and atomic-force microscopy. It is shown that treatment of the GaSb(100) surface by any (NH_4)_2S solution leads to removal of the native oxide layer from the semiconductor surface and the formation of a passivating layer consisting of various gallium and antimony sulfides and oxides. The surface with the lowest roughness (RMS = 0.85 nm) is formed after semiconductor treatment with 4% aqueous ammonium sulfide solution for 30 min. Herewith, the atomic concentration ratio Ga/Sb at the surface is ~2. It is also found that aqueous ammonium sulfide solutions do not react with elemental antimony incorporated into the native-oxide layer. The latter causes a leakage current and Fermi-level pinning at the GaSb(100) surface. However, a 4% (NH_4)_2S solution in isopropanol removes elemental antimony almost completely; herewith, the semiconductor surface remains stoichiometric if a treatment duration is up to 13 min.

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Photoluminescence properties of cuprous phosphide prepared through phosphating copper with a native oxide layer

RSC Advances ◽

10.1039/d1ra07112b ◽

2021 ◽

Vol 11 (54) ◽

pp. 34095-34100

Author(s):

Xue Peng ◽

Yanfei Lv ◽

Li Fu ◽

Fei Chen ◽

Weitao Su ◽

...

Keyword(s):

Oxide Layer ◽

Cuprous Oxide ◽

Fluorescence Properties ◽

Native Oxide ◽

Native Oxide Layer ◽

Photoluminescence Properties ◽

Band Bending ◽

Carrier Traps

The presence of cuprous oxide results in band bending at the interface between cuprous phosphide and cuprous oxide, forming carrier traps, which improves the fluorescence properties of cuprous phosphide.

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Effect of Interface Native Oxide Layer on the Properties of Annealed Ni/SiC Contacts

Materials Science Forum ◽

10.4028/www.scientific.net/msf.740-742.485 ◽

2013 ◽

Vol 740-742 ◽

pp. 485-489 ◽

Cited By ~ 2

Author(s):

Wei Huang ◽

Shao Hui Chang ◽

Xue Chao Liu ◽

Zheng Zheng Li ◽

Tian Yu Zhou ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Temperature ◽

Oxide Layer ◽

Native Oxide ◽

Native Oxide Layer ◽

High Temperature Annealing ◽

Contact Interface ◽

Ohmic Behavior ◽

Transmission Electron

The near-SiC-interfaces of annealed Ni/SiC contacts were observed directly by high-resolution transmission electron microscopy (HRTEM). 1 nm native oxide layer was observed in the as-deposited contact interface. The native oxide layer cannot be removed at 650°C through rapid thermal annealing (RTA) and it was completely removed at 1000°C RTA. The residue of native oxide layer resulted in the Schottky characters. High temperature annealing (>950°C) not only removes the oxide layer in the near-SiC-interface, but also forms a well arranged flat Ni2Si/SiC interface, which contribute to the formation of ohmic behavior.

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On the Interface between Plasma Fluorocarbon Films and 316L Stainless Steel Substrates for Advanced Coated Stents

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.409.117 ◽

2011 ◽

Vol 409 ◽

pp. 117-122 ◽

Cited By ~ 4

Author(s):

Maxime Cloutier ◽

Stéphane Turgeon ◽

P. Chevallier ◽

D. Mantovani

Keyword(s):

Stainless Steel ◽

Oxide Layer ◽

Photoelectron Spectroscopy ◽

Corrosion Behaviour ◽

Drug Carrier ◽

Native Oxide ◽

Interfacial Region ◽

Native Oxide Layer ◽

Corrosion Performance ◽

Stent Restenosis

As intravascular biomedical devices, metallic stents are particularly susceptible to corrosion induced by the physiological environment, causing the degradation of mechanical properties and leading to the release of toxic and carcinogenic ions from the SS316L bulk. Therefore, several works have been focused on the development of an ultra-thin fluorocarbon coating that could act both as a drug-carrier for in-stent restenosis and as an anti-corrosion barrier. However, the increase of the corrosion performance was limited by the inevitable permeability of the coating, which exposed some of the sensitive interfacial region to the corrosive environment. Indeed, in previous works, adhesion and growth rate of the film were promoted by the removal of the native oxide layer of the stainless steel which is inhomogeneous, brittle and mechanically unstable. Further refinements of the interface are therefore required in order to enhance the overall corrosion performance without compromising the fluorocarbon film properties and adhesion. Hence, the aim of this work was to enhance the corrosion behaviour of coated SS316L by the creation of a controlled interfacial oxide layer. The native oxide layer was first removed under vacuum and the bare metal surface was subjected to a plasma-reoxidation treatment. Tafel measurements were used to assess the corrosion rates of the specimens. Coated and uncoated modified interfaces were also characterized by X-Ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM).

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Rapid Thermal Annealed Undoped LPCVD Si/Single Crystal Si Substrate Structures with an Implant of Si Near Interfaces

MRS Proceedings ◽

10.1557/proc-106-273 ◽

1987 ◽

Vol 106 ◽

Cited By ~ 3

Author(s):

S. Ogawa ◽

S. Okuda ◽

T. Kouzaki ◽

T. Yoshida ◽

Y. Yoshioka

Keyword(s):

Single Crystal ◽

Epitaxial Growth ◽

Oxide Layer ◽

Point Of View ◽

Native Oxide ◽

Native Oxide Layer ◽

Si Substrate ◽

Transmission Electron ◽

Amorphous Si ◽

Oxygen Atoms

ABSTRACTThe breaking up of a native oxide layer of a LPCVD amorphous Si/single crystal n+Si substrate interface by a rapid-thermal annealing was studied from the point of view of oxygen movement and morphological change. Oxygen atoms began to move at 1025 °C. After annealing at 1115 °C for 30sec, the quantity of oxygen atoms near the interface decreased dramatically and a silicon implant near the interface could enhance the decrease. More detailed observation was carried out by cross-section high-resolution transmission electron microscopy. After annealing at 940 °C for 30sec, the native oxide layer was continuous. On the qther hand, with a silicon implant near the interface, it changed into small oxide balls and an epitaxial growth occurred in the LPCVD layer with twins caused by these oxide balls. After annealing at 1115°C for 30sec, even without the silicon implant, a complete epitaxial growth occurred but it seemed that some SiOx particles dissolved into a single crystal Si layer near the interface.

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Composition and band structure of the native oxide nanolayer on the ion beam treated surface of the GaAs wafer

Физика и техника полупроводников ◽

10.21883/ftp.2018.05.45850.39 ◽

2018 ◽

Vol 52 (5) ◽

pp. 506

Author(s):

V.M. Mikoushkin ◽

V.V. Bryzgalov ◽

S.Yu. Nikonov ◽

A.P. Solonitsyna ◽

D.E. Marchenko

Keyword(s):

Oxide Layer ◽

Photoelectron Spectroscopy ◽

Ion Beam ◽

Native Oxide ◽

Chemical Compositions ◽

Native Oxide Layer ◽

Band Diagram ◽

Clean Surface ◽

Gaas Wafer ◽

Dielectric Layers

AbstractDetailed information on GaAs oxide properties is important for solving the problem of passivating and dielectric layers in the GaAs-based electronics. The elemental and chemical compositions of the native oxide layer grown on the atomically clean surface of an n -GaAs (100) wafer etched by Ar^+ ions have been studied by synchrotron-based photoelectron spectroscopy. It has been revealed that the oxide layer is essentially enriched in the Ga_2O_3 phase which is known to be a quite good dielectric as compared to As_2O_3. The gallium to arsenic ratio reaches the value as high as [Ga]/[As] = 1.5 in the course of oxidation. The Ga-enrichment occurs supposedly due to diffusion away of As released in preferential oxidation of Ga atoms. A band diagram was constructed for the native oxide nanolayer on the n -GaAs wafer. It has been shown that this natural nanostructure has features of a p–n heterojunction.

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