scholarly journals Growth mode study of MgCl2 on Au foil and Si (111) 7x7, under Ultra High Vacuum by XPS

2011 ◽  
Vol 1 (1) ◽  
pp. 13-16
Author(s):  
S. Karakalos
Keyword(s):  
Surface Roughness ◽  
Photoelectron Spectroscopy ◽  
Magnesium Chloride ◽  
High Vacuum ◽  
Layer Growth ◽  
Ultra High Vacuum ◽  
Growth Mode ◽  
Layer By Layer ◽  
X Ray ◽  
Reconstructed Surface

The growth mode of MgCl2 on Au foil and Si (111) 7x7 reconstructed surface under UHV conditions, was investigated by X-ray Photoelectron Spectroscopy (XPS). Magnesium chloride grows with the Frank-van der Merve, (FM) growth mode on the Au foil. On Si surface there is evidence for the layer by layer growth of MgCl2 but leaving uncovered silicon areas at the first steps of deposition due to the Si (111)7x7 surface roughness.

scholarly journals Growth Mode Study of MgCl2 on Ti (0001) and SiO2 under Ultra High Vacuum by XPS

2012 ◽  
Vol 2 (6) ◽  
pp. 291-294
Author(s):  
S. Karakalos
Keyword(s):  
Single Crystal ◽  
Photoelectron Spectroscopy ◽  
Magnesium Chloride ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Growth Mode ◽  
X Ray ◽  
Mode Study

The growth mode of MgCl2 on Ti (0001) and on SiO2 grown on Si (100) was investigated by X-ray Photoelectron Spectroscopy (XPS) under UHV conditions. Magnesium chloride grows on both Ti (0001) single crystal and SiO2 following the Frank-van der Merve, (FM) growth mode.

A compact UHV X-ray diffractometer for studying surfaces and interfaces

1998 ◽  
Vol 5 (3) ◽  
pp. 887-889
Author(s):  
Yoshikazu Fujii ◽  
Takeshi Nakamura ◽  
Mutsumi Kai ◽  
Kentaroh Yoshida
Keyword(s):  
High Vacuum ◽  
Layer Growth ◽  
Ultra High Vacuum ◽  
Layer By Layer ◽  
Crystal Surfaces ◽  
X Ray ◽  
Surfaces And Interfaces ◽  
Optical Table ◽  
Specimen Orientation

A compact ultra-high-vacuum (UHV) X-ray diffractometer for surface glancing X-ray scattering has been constructed. All the equipment, including a rotating-anode source of 18 kW and a UHV specimen chamber, is arranged on one optical table of dimensions 70 × 90 cm. The specimen chamber is 14 cm in diameter and 20 cm high and can be evacuated up to 3 × 10−8 Pa. It is equipped with two Be windows of thicknesses 0.2 and 0.4 mm. Specimen orientation in the vacuum is controlled from the outside. The specimen can be heated up to 773 K. The chamber has two evaporation cells and can be used for in situ observations of growing crystal surfaces. Using this instrument, we observed a mechanically polished Ag surface and successfully made an in situ observation of the layer-by-layer growth of a PbSe(111) surface. The instrument will be useful for preliminary experiments using laboratory sources, prior to final measurements at synchrotron radiation facilities.

Characterization of the a-SN/CDTE(110) Interface by Angle-Resolved X-Ray Photoemission

1986 ◽  
Vol 77 ◽  
Author(s):  
Tzer-Shen Lin ◽  
William J. Partin ◽  
Yip-Wah Chung
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Layer By Layer ◽  
Tungsten Filament ◽  
X Ray ◽  
Semiconductor Heterostructure ◽  
Argon Sputtering ◽  
Abrupt Junction

ABSTRACTStoichiometric and atomically clean CdTe(110) surfaces have been prepared by suitable chemical etching, followed by argon sputtering, and sample annealing in ultra-high vacuum. Cubic (α) -tin was grown on CdTe(110) by tin evaporation from a tungsten filament at a substrate temperature of 30 °C. Angle-resolved X-ray photoelectron spectroscopy (ARXPS) was used to determine the a-Sn growth mechanism and the composition profile of this semiconductor heterostructure nondestructively. From our analyses, we conclude that a-Sn grows on CdTe(110) at 30 °C by a layer by layer mechanism and forms an abrupt junction with CdTe(110).

Synthesis and Characterization of Zn Oxide Hexagonal Nano-Pole Films on Quartz Glass Substrate

2009 ◽  
Vol 7 (1) ◽  
Author(s):  
Jie Chen ◽  
Jun Wang
Keyword(s):  
Growth Mechanism ◽  
Quartz Glass ◽  
Photoelectron Spectroscopy ◽  
Glass Substrate ◽  
Sol Gel ◽  
Layer Growth ◽  
Layer By Layer ◽  
Quartz Glass Substrate ◽  
Wurtzite Phase ◽  
X Ray

Hexagon-shaped Zn oxide nano-pole films with terraces and steps have been successfully fabricated by means of a combined approach involving sol-gel process, high-temperature heat treatment, and the hydrothermal method. The surface chemistry and morphological features of the films were characterized by means of x-ray photoelectron spectroscopy and scanning electron microcopy. All the diffraction peaks in x-ray diffraction pattern match with those of the hexagonal wurtzite phase of Zn oxide. Transmittance measurements show that the optical transmittance of the sample synthesized at 520°C on quartz glass substrate is the highest, reaching about 65% in the visible-light region. Based on the detailed structural characterization and the nucleation-growth kinetics, we find that the whole crystallization process of wurtzite Zn oxide nano-poles includes nanocatalysis and layer-by-layer growth mechanism. The present study provides an important understanding of the growth mechanism for nano-pole synthesis of Zn oxide and related materials.

scholarly journals Initial Growth and Crystallization Onset of Plasma Enhanced-Atomic Layer Deposited ZnO

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 291
Author(s):  
Alberto Perrotta ◽  
Julian Pilz ◽  
Roland Resel ◽  
Oliver Werzer ◽  
Anna Maria Coclite
Keyword(s):  
Atomic Layer ◽  
Layer Growth ◽  
Growth Mode ◽  
Ex Situ ◽  
Native Oxide ◽  
Layer By Layer ◽  
Initial Growth ◽  
Island Growth ◽  
X Ray ◽  
Crystallization Onset

Direct plasma enhanced-atomic layer deposition (PE-ALD) is adopted for the growth of ZnO on c-Si with native oxide at room temperature. The initial stages of growth both in terms of thickness evolution and crystallization onset are followed ex-situ by a combination of spectroscopic ellipsometry and X-ray based techniques (diffraction, reflectivity, and fluorescence). Differently from the growth mode usually reported for thermal ALD ZnO (i.e., substrate-inhibited island growth), the effect of plasma surface activation resulted in a substrate-enhanced island growth. A transient region of accelerated island formation was found within the first 2 nm of deposition, resulting in the growth of amorphous ZnO as witnessed with grazing incidence X-ray diffraction. After the islands coalesced and a continuous layer formed, the first crystallites were found to grow, starting the layer-by-layer growth mode. High-temperature ALD ZnO layers were also investigated in terms of crystallization onset, showing that layers are amorphous up to a thickness of 3 nm, irrespective of the deposition temperature and growth orientation.

Growth of CaFeOX/LaFeO3 Superlattice on SrTiO3(100) Substrates

2011 ◽  
Vol 1292 ◽  
Author(s):  
Nobuyuki Iwata ◽  
Mark Huijben ◽  
Guus Rijnders ◽  
Hiroshi Yamamoto ◽  
Dave H. A. Blank
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Layer Growth ◽  
Laser Deposition ◽  
Growth Mode ◽  
Layer By Layer ◽  
X Ray Diffraction ◽  
Reciprocal Space Mapping ◽  
X Ray

ABSTRACTThe CaFeOX(CFO) and LaFeO3(LFO) thin films as well as superlattices were fabricated on SrTiO3(100) substrates by pulsed laser deposition (PLD) method. The tetragonal LFO film grew with layer-by-layer growth mode until approximately 40 layers. In the case of CFO, initial three layers showed layer-by-layer growth, and afterward the growth mode was transferred to two layers-by-two layers (TLTL) growth mode. The RHEED oscillation was observed until the end of the growth, approximately 50nm. Orthorhombic twin CaFeO2.5 (CFO2.5) structure was obtained. However, it is expected that the initial three CFO layers are CaFeO3 (CFO3) with the valence of Fe4+. The CFO and LFO superlattice showed a step-terraces surface, and the superlattice satellite peaks in a 2θ-θ and reciprocal space mapping (RSM) x-ray diffraction (XRD) measurements, indicating that the clear interfaces were fabricated.

Fundamental study of the interaction of Ti atoms with spruce surfaces

Holzforschung ◽  
2007 ◽  
Vol 61 (5) ◽  
pp. 523-527 ◽  
Author(s):  
Lothar Klarhöfer ◽  
Florian Voigts ◽  
Dominik Schwendt ◽  
Burkhard Roos ◽  
Wolfgang Viöl ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Strong Interactions ◽  
Titanium Oxide Film ◽  
Fundamental Study ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Metal Atoms

Abstract Metastable induced electron spectroscopy (MIES), ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were applied to study the interaction of Ti metal atoms with spruce surfaces. Spruce surfaces were produced by planing splints from a spruce bar. Ti atoms were adsorbed from a metal evaporator under ultra-high vacuum conditions. The amount adsorbed corresponds to 10 monolayer equivalents. Strong interactions between the spruce surface and metals atoms occurred. Impinging Ti atoms were oxidized by the spruce surface. No Ti agglomeration or particle formation was observed. The surface was smoothed by the Ti applied and was completely covered by a titanium oxide film.

CORRELATION AMONG THE ELECTRONIC STATE IN Sn-DOPED YBCO SYSTEM

1991 ◽  
Vol 05 (08) ◽  
pp. 581-585
Author(s):  
H. ZHANG ◽  
S.Q. FENG ◽  
Q.R. FENG ◽  
X. ZHU
Keyword(s):  
Content Analysis ◽  
Binding Energy ◽  
Photoelectron Spectroscopy ◽  
Strong Correlation ◽  
Single Phase ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Electronic States ◽  
Ultra High Vacuum ◽  
X Ray

We have performed an X-ray photoelectron spectroscopy investigation on single-phase samples of Sn -doped YBCO system, together with structure analysis, oxygen content analysis, and superconductivity measurements. The experiment gave evidence that there is a strong correlation between the electronic states of copper and oxygen. When the sample was heated to 600°C for 20 minutes in vacuum chamber, the oxygen escaped from the sample, the binding energy of Cu 2p was decreased, and the two indistinct components of O 1s became clear. Keeping the sample in ultra-high vacuum for 24 hours, a similar result was obtained.

scholarly journals Investigation of interaction of Co, Mn and Fe atoms with the calcite by X-ray photoelectron spectroscopy

2019 ◽  
Vol 64 (1) ◽  
pp. 89-95
Author(s):  
T. T. Magkoev ◽  
V. B. Zaalishvili ◽  
O. G. Burdzieva ◽  
G. E. Tuaev ◽  
G. S. Grigorkina
Keyword(s):  
Solid Solutions ◽  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
X Ray ◽  
Surface Compounds ◽  
Adsorption Systems

Adsorption of atoms of Co, Mn, Fe on the calcite surface in ultra-high vacuum and the interaction of the formed adsorption systems with the water have been studied by means of X-ray photoelectron spectroscopy. It is shown that Mn and Fe form solid solutions CaCO3/Mn(Fe)CO3 on the calcite surface, whereas Co preferentially forms CoO and Co3O4. Upon interaction with water the surface compounds formed by Mn and Fe do not undergo notable changes, unlike the Co oxides which partially transform into soluble hydroxylated complexes.

scholarly journals Selective Growth of Al2O3 on Size-Selected Platinum Clusters by Atomic Layer Deposition

2019 ◽  
Author(s):  
Timothy J. Gorey ◽  
Yang Dai ◽  
Scott Anderson ◽  
Sungsik Lee ◽  
Sungwon Lee ◽  
...  
Keyword(s):  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Atomic Layer ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Dimensional Structure ◽  
Alumina Layer ◽  
X Ray ◽  
Layer Deposition

In heterogeneous catalysis, atomic layer deposition (ALD) has been developed as a tool to stabilize and reduce carbon deposition on supported nanoparticles. Here, we discuss use of high vacuum ALD to deposit alumina films on size-selected, sub-nanometer Pt/SiO2 model catalysts. Mass-selected Pt24 clusters were deposited on oxidized Si(100), to form model Pt24/SiO2 catalysts with particles shown to be just under 1 nm, with multilayer three dimensional structure. Alternating exposures to trimethylaluminum and water vapor in an ultra-high vacuum chamber were used to grow alumina on the samples without exposing them to air. The samples were probed in situ using X-ray photoelectron spectroscopy (XPS), low-energy ion scattering spectroscopy (ISS), and CO temperature-programmed desorption (TPD). Additional samples were prepared for ex situ experiments using grazing incidence small angle x-ray scattering spectroscopy (GISAXS). Alumina growth is found to initiate at least 60 times more efficiently at the Pt24 cluster sites, compared to bare SiO2/Si, with a single ALD cycle depositing a full alumina layer on top of the clusters, with substantial additional alumina growth initiating on SiO2 sites surrounding the clusters. As a result, the clusters were completely passivated, with no exposed Pt binding sites.

Sign in / Sign up

Export Citation Format

Share Document