Insertion of Iron Decorated Organic–Inorganic Cage-Like Polyhedral Oligomeric Silsesquioxanes between Clay Platelets by Langmuir Schaefer Deposition

Tuning the architecture of multilayer nanostructures by exploiting the properties of their constituents is a versatile way to develop multifunctional films. Herein, we report a bottom-up approach for the fabrication of highly ordered hybrid films consisting of dimethyldioctadecylammonium (DODA), iron decorated polyhedral oligomeric silsesquioxanes (POSS), and montmorillonite clay platelets. Clay platelets provided the template where Fe/POSS moieties were grafted by the use of the surfactant. Driven by the iron ions present, DODA adopted a staggered arrangement, which is essential to realize the controllable layer-by-layer growth of the film. The elemental composition of the film was studied by X-ray photoelectron spectroscopy and X-ray reflectivity confirmed the existence of smooth interfaces between the different layers.

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

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2051 ◽

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.

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Kinetic Control of CaF2 on Si(111) Growth Morphology

MRS Proceedings ◽

10.1557/proc-312-207 ◽

1993 ◽

Vol 312 ◽

Author(s):

J. D. Denlinger ◽

Eli Rotenberg ◽

U. Hessingert ◽

M. Leskovar ◽

Marjorie A. Olmstead

Keyword(s):

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Layer Growth ◽

Layer By Layer ◽

X Ray ◽

Photoelectron Diffraction ◽

Triple Layer ◽

Growth Modes ◽

Level Shifts

AbstractThin (0.5 to 8 triple layer) CaF2 on Si(111) films were grown using molecular beam epitaxy (MBE) and characterized using an in situ combination of x-ray photoelectron spectroscopy (XPS) and componentresolved x-ray photoelectron diffraction (XPD). We identified surface, bulk-like, and interface F and Ca core-level shifts and used the XPS shifts and XPD modulations to identify the growth modes as a function of the kinetic parameters of CaF2 flux and Si temperature. We identify 3 distinct regimes: (i) for high temperatures and flux we find a complete reacted F-Ca-Si layer, overlaid by 2 layer high islands which coalesce, followed by layer-by-layer growth, (ii) for high temperature and low flux, we find the reacted F-Ca-Si layer to be partially covered with thick islands, and (iii) for low temperatures we find an incompletely occupied F-Ca-Si layer followed by layer-by-layer growth. In all cases we find the buried interface to be structurally identical to the unburied F-Ca-Si layer

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

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.4 ◽

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.

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Nitrogen (N2) Implantation to Suppress Growth of Interfacial Oxide in Mocvd Bst and Sputtered Bst Films

MRS Proceedings ◽

10.1557/proc-567-521 ◽

1999 ◽

Vol 567 ◽

Cited By ~ 5

Author(s):

Renee Nieh ◽

Wen-Jie Qi ◽

Yongjoo Jeon ◽

Byoung Hun Lee ◽

Aaron Lucas ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Interfacial Layer ◽

Gate Dielectric ◽

Nitrogen Concentration ◽

Chemical Vapor ◽

Future Generation ◽

Oxide Thickness ◽

Layer Growth ◽

X Ray ◽

Bst Films

ABSTRACTBa0.5Sr0.5TiO3 (BST) is one of the high-k candidates for replacing SiO2 as the gate dielectric in future generation devices. The biggest obstacle to scaling the equivalent oxide thickness (EOT) of BST is an interfacial layer, SixOy, which forms between BST and Si. Nitrogen (N2) implantation into the Si substrate has been proposed to reduce the growth of this interfacial layer. In this study, capacitors (Pt/BST/Si) were fabricated by depositing thin BST films (50Å) onto N2 implanted Si in order to evaluate the effects of implant dose and annealing conditions on EOT. It was found that N2 implantation reduced the EOT of RF magnetron sputtered and Metal Oxide Chemical Vapor Deposition (MOCVD) BST films by ∼20% and ∼33%, respectively. For sputtered BST, an implant dose of 1×1014cm−;2 provided sufficient nitrogen concentration without residual implant damage after annealing. X-ray photoelectron spectroscopy data confirmed that the reduction in EOT is due to a reduction in the interfacial layer growth. X-ray diffraction spectra revealed typical polycrystalline structure with (111) and (200) preferential orientations for both films. Leakage for these 50Å BST films is on the order of 10−8 to 10−5 A/cm2—lower than oxynitrides with comparable EOTs.

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

Crystals ◽

10.3390/cryst10040291 ◽

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.

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The Electronic Structures of Fullerene/Transition-Metal Hybrid Material

MRS Proceedings ◽

10.1557/proc-1081-p07-01 ◽

2008 ◽

Vol 1081 ◽

Author(s):

Yoshihiro Matsumoto ◽

Seiji Sakai ◽

Hiroshi Naramoto ◽

Norie Hirao ◽

Yuji Baba ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Electronic Structures ◽

Line Broadening ◽

Hybrid Films ◽

Xps Spectra ◽

X Ray ◽

Nexafs Spectroscopy ◽

Homo Level ◽

Valence Band Region ◽

X Ray Absorption

ABSTRACTLocal electronic structures of C60-Co hybrid films have been studied by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. XPS spectra of C 1s main and satellite peaks for the C60-Co films show binding-energy shifts and also line-broadening compared to those in a pure C60 film. In addition, XPS spectra in valence band region suggest an appearance of three new components at near Fermi level and HOMO level in the C60-Co film. These results are attributed to hybridizations between Co 3d band and C60 LUMO. The same effects have been observed in NEAXFS spectra at C 1s excitations.

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Surfactant-Mediated Growth of Ge/Si(001) Interface Studied by XPD

Surface Review and Letters ◽

10.1142/s0218625x9800030x ◽

1998 ◽

Vol 05 (01) ◽

pp. 157-161 ◽

Cited By ~ 6

Author(s):

R. Gunnella ◽

P. Castrucci ◽

N. Pinto ◽

P. Cucculelli ◽

I. Davoli ◽

...

Keyword(s):

High Temperature ◽

Auger Electron ◽

Layer Growth ◽

Layer By Layer ◽

Growth Morphology ◽

High Quality ◽

X Ray ◽

Photoelectron Diffraction ◽

Quality Degradation ◽

Cap Layer

The influence of Sb as a surfactant on the formation of Si/Ge interface is studied by means of XPD (X-ray photoelectron diffraction) and AED (Auger electron diffraction) from Ge and Si core levels. The technique employed is particularly suitable for checking the film tetragonal distortion, the growth morphology and the sharpness of the interface. We found a layer by layer growth mode for 3 ML of Ge on Si(001) and related values of strain of the film close to the value predicted by the elastic theory which enforces the use of such a surfactant to obtain high quality and sharp heterostructures. In addition, studying the influence of 3 ML of the Si cap layer on the 3 ML Ge, we obtain no indication of Ge segregation into the Si cap layer. Finally, evidences of quality degradation after high temperature (T > 600° C ) annealing are shown.

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Functionalized Polymeric Nanoparticles

MRS Proceedings ◽

10.1557/proc-818-m12.9.1 ◽

2004 ◽

Vol 818 ◽

Cited By ~ 1

Author(s):

Eric Sussman ◽

Michael Clark ◽

V. Prasad Shastri

Keyword(s):

Drug Delivery ◽

Photoelectron Spectroscopy ◽

Cellular Localization ◽

Polymeric Nanoparticles ◽

Fluorescent Microscopy ◽

Single Step ◽

Layer By Layer ◽

Bearing Surface ◽

X Ray ◽

Surface Functionality

AbstractSurface-functionalized polymeric nanoparticles (NP) are a versatile medium for drug delivery and imaging. The surface functionality is typically exploited to introduce molecules such as polymers and biomolecules to improve cellular localization, DNA binding and circulation. NP bearing surface functionality are typically prepared from polymers possessing functionalizable backbones or by layer-by-layer assembly of polyelectrolytes onto unmodified particles. We have developed a process to produce functionalized polymeric NP in a single step using non-functionalized polymers. This is achieved by the entrapment of polymeric functional moieties from an aqueous phase in a rapidly solidifying polymer core. NP were characterized using light scattering, scanning electron microscopy, zeta potential (ζ) measurement, fluorescent microscopy, and X-ray photoelectron spectroscopy (XPS). Stable NP ranging in diameter from 70 to 400nm with narrow polydispersity (PDI) can be produced by this process. The presence of functional moieties on the NP surface was verified by isoelectric point measurement and XPS. We foresee a number of uses for these functionalized nanoparticles, including drug delivery and modification of hard and soft material surfaces (both synthetic and biological) for tissue engineering.

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

MRS Proceedings ◽

10.1557/opl.2011.245 ◽

2011 ◽

Vol 1292 ◽

Cited By ~ 3

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.

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