Chemical Structures of Native Oxides Formed During Wet Chemical Treatments on NH4F Treated Si(111) Surfaces

1992 ◽  
Vol 259 ◽  
Author(s):  
Takeo Hattori ◽  
Hiroki Ogawa
Keyword(s):  
Photoelectron Spectroscopy ◽  
Attenuated Total Reflection ◽  
Native Oxide ◽  
X Ray ◽  
Chemical Treatments ◽  
Chemical Structures ◽  
Native Oxides ◽  
Ft Ir ◽  
Wet Chemical ◽  
Silicon Interface

ABSTRACTChemical structures of native oxides formed during wet chemical treatments on NH4F treated Si(111) surfaces were investigated using X-ray Photoelectron Spectroscopy (XPS) and Fourier Transformed Infrared Attenuated Total Reflection(FT-IR-ATR). It was found that the amounts of Si-H bonds in native oxides and those at native oxide/silicon interface are negligibly small in the case of native oxides formed in H2SO4-H2O2-H2O solution. Based on this discovery, it was confirmed that native oxides can be characterized by the amount of Si-H bonds in native oxides. Furthermore, it was found that the combination of various wet chemical treatments with the treatment in NH4OH-H2O2-H2O solution results in the drastic decrease in the amount of Si-H bonds in native oxides.

Controlled Stepwise Growth of Siloxane Chains Using Bivalent Building Units With Different Functionalities

2010 ◽  
Vol 1272 ◽  
Author(s):  
Nils Salingue ◽  
Dominic Lingenfelser ◽  
Pavel Prunici ◽  
Hess Peter
Keyword(s):  
Photoelectron Spectroscopy ◽  
Attenuated Total Reflection ◽  
Silicon Surfaces ◽  
Chain Growth ◽  
One Dimensional ◽  
X Ray ◽  
Sioh Group ◽  
Wet Chemical ◽  
Chemical Condensation

AbstractOrganic/inorganic hybrids of silicon and their subsequent chemical modification are of interest for tailoring and structuring surfaces on the nanoscale. The formation of monolayers on hydroxylated silicon surfaces was employed to synthesize molecular dimethylsiloxane chains by wet-chemical condensation reactions, using dimethylmonochlorosilane as the precursor. The SiH group of the resulting dimethylsilyl termination could be selectively oxidized to the SiOH group, which opened the possibility of bonding another species. By repeating the condensation and oxidation cycle the stepwise growth of one-dimensional dimethylsiloxane chains was achieved. The ongoing chain growth was characterized by attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy, x-ray photoelectron spectroscopy (XPS), spectroscopic ellipsometry (SE), and determination of the surface energy by contact-angle experiments.

Molecular Composition and Orientation of Interstitial versus Surface Silicon Oxides for Si(111)/SiO2 and Si(100)/SiO2 Interfaces using FT-IR and X-ray Photoelectron Spectroscopies

2003 ◽  
Vol 57 (6) ◽  
pp. 628-635 ◽  
Author(s):  
Georgia Kandilioti ◽  
Angeliki Siokou ◽  
Vasiliki Papaefthimiou ◽  
Stella Kennou ◽  
Vasilis G. Gregoriou
Keyword(s):  
Thermal Oxidation ◽  
Photoelectron Spectroscopy ◽  
Silicon Oxide ◽  
Surface Film ◽  
Spectroscopic Studies ◽  
Native Oxide ◽  
Hydroxyl Groups ◽  
X Ray ◽  
Ft Ir ◽  
On Chip

This work represents a characterization study of silicon oxide on Si(111) and Si(100) surfaces intended for use as substrates in organic light-emitting diodes (OLEDs) on chip devices. Samples have been prepared using either native oxide formation or thermal oxidation, and they have also been treated for activation of hydroxyl groups on their surface. Both Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) have been used in order to understand the molecular orientation as well as the chemical composition of the various oxide types formed during these different oxidation processes. These spectroscopic studies reveal the formation of two different types of oxides on these substrates. The first type is a thin oxide layer on the surface, whereas the second type, called interstitial, is found deeper in the substrate. Specifically, it was found that the Si(100) substrate forms a randomly oriented interstitial oxide, whereas the presence of a lower quantity but more oriented interstitial oxide was found for the Si(111) substrate. In addition, we report for the first time the position of the impurity oxygen for Si(111) substrates at 1122 cm−1. Finally, in both Si(100) and Si(111) substrates, the thin (<15 Å) silicon oxide layers are oriented and appear to contain silicon atoms of similar oxidation states. In contrast, both the thicker surface film (100 Å) as well as the interstitial oxide produced by the thermal oxidation procedure show random orientation and relative uniformity. Overall these orientation studies clearly show that the formation process of surface oxides in different substrates clearly creates species that are oriented differently with respect to the surface.

Chemical Structures of Native Oxides Formed during Wet Chemical Treatments

1989 ◽  
Vol 28 (Part 2, No. 2) ◽  
pp. L296-L298 ◽  
Author(s):  
Takeo Hattori ◽  
Kazuhiko Takase ◽  
Hiroaki Yamagishi ◽  
Rinshi Sugino ◽  
Yasuo Nara ◽  
...  
Keyword(s):  
Chemical Treatments ◽  
Chemical Structures ◽  
Native Oxides ◽  
Wet Chemical

Influence of BHF Treatments on Hydrogen-Terminated Si(100) Surfaces

1997 ◽  
Vol 477 ◽  
Author(s):  
T. Osada ◽  
Y. Kawazawa ◽  
S. Miyazaki ◽  
M. Hirose
Keyword(s):  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Ionic Species ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
The Other ◽  
Reflection Spectroscopy ◽  
X Ray ◽  
Molar Ratios ◽  
Ft Ir

ABSTRACTThe hydrogen bonding features of Si(100) surfaces treated with BHF (NH4F/HF/H2O) have been studied by Fourier transform infrared attenuated total reflection spectroscopy (FT-IR-ATR). The amount of residual silicon-fluorine bonds on Si(100) surfaces has been evaluated by X-ray photoelectron spectroscopy (XPS). It is found that Si-H3 bonds appears to be preferentially removed by OH ions so as to increase the surface SiH2 and SiH bonds. On the other hand, it is likely that fluorine-containing ionic species such as HF2 might attack the backbonds of surface hydrides to produce Si-H3 and Si-F bonds. ATR spectra have shown that a BHF treated Si(100) surface in 5∼10% NH4F with molar ratios of HF/NH4F=0.37∼0.56 (pH=3.7∼4.0) at a treatment time of 5 minutes is atomically flatter than that treated in BHF containing 15∼20% NH4F. This is because the amount of residual Si-F bonds on Si(100) increases with HF2 concentration in BHF and these Si-F bonds enhance attacking of silicon backbonds of Si-F bond by OH− and HF2− ions.

Wet Chemical Cleaning of Germanium Surfaces for Growth of High-k Dielectrics

2006 ◽  
Vol 917 ◽  
Author(s):  
Sandrine Rivillon Amy ◽  
Yves J Chabal ◽  
Fabrice Amy ◽  
Antoine Kahn ◽  
Cristiano Krugg ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Water Soluble ◽  
Chemical Cleaning ◽  
X Ray ◽  
Native Oxides ◽  
High K ◽  
Controlled Environments ◽  
Wet Chemical ◽  
The Stability ◽  
Poor Stability

AbstractOne of the major difficulties preventing the wide use of germanium (epi or bulk) as a gate material is the poor stability of its oxide, leading to reproducibility and reliability issues. In contrast to silicon, the nature and thickness of Ge “native” oxides are history dependent, and most phases of germanium oxide are water-soluble. As a result, the procedures for passivating Ge surfaces with hydrogen (HF last) are more complex and less forgiving.We have used infrared absorption spectroscopy and x-ray photoelectron spectroscopy to investigate the nature of oxidized and H-terminated Ge surfaces. The GeO2, GeO and GeC phases have been identified and quantified as a function of processing conditions. The stability of the H-terminated surfaces has been examined in air and in controlled environments. The H-passivated Ge surfaces are found to be much less stable in air than H-terminated Si surfaces.

Studies on the Surface of PTFE Membranes Treated with Atmospheric Pressure Low Temperature Plasma of Ar and Ar/H2

2014 ◽  
Vol 1048 ◽  
pp. 440-443
Author(s):  
Naohisa Akashi ◽  
Katsuhiko Hosoi ◽  
Shin-ichi Kuroda
Keyword(s):  
Low Temperature ◽  
Photoelectron Spectroscopy ◽  
Atmospheric Pressure ◽  
Spectroscopic Analysis ◽  
Attenuated Total Reflection ◽  
Low Temperature Plasma ◽  
Temperature Plasma ◽  
X Ray ◽  
Ft Ir ◽  
Ir Spectroscopic

Polytetrafluoroethylene (PTFE) has many excellent engineering applications for its great properties. We investigated the surface of the PTFE membranes treated with atmospheric pressure low temperature plasma in Ar and Ar/H2 to confirm the effectiveness for introducing functional groups as surface modifications. From the results of attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopic analysis and X-ray photoelectron spectroscopy (XPS), it was found that the Ar/H2 plasma was more effective for proceeding defluorination reactions and introducing oxygen moieties compared to Ar plasma under the experimental condition. On the other hand, from the results of scanning electron microscopy (SEM), there were little differences in plasma-treated samples.

STUDY OF THE GATE INSULATOR/SILICON INTERFACE UTILIZING SOFT AND HARD X-RAY PHOTOELECTRON SPECTROSCOPY AT SPring-8

2006 ◽  
Vol 16 (01) ◽  
pp. 353-364 ◽  
Author(s):  
T. HATTORI ◽  
H. NOHIRA ◽  
K. AZUMA ◽  
K. W. SAKAI ◽  
K. NAKAJIMA ◽  
...  
Keyword(s):  
Photon Energy ◽  
Energy Resolution ◽  
Photoelectron Spectroscopy ◽  
Chemical Structure ◽  
Gate Insulator ◽  
X Ray ◽  
Chemical Structures ◽  
High K ◽  
High K Dielectric ◽  
Silicon Interface

The chemical structures of SiO 2/ Si interfaces were studied by photoelectron spectroscopy using high-brilliance soft X-ray with photon energy ranging from 500 to 1500 eV at Super Photon ring 8 GeV(SPring-8) and it is able to probe a depth of about 1.2 to 3 nm with energy resolution of 100 meV. On the other hand, high-brilliance hard X-ray with photon energy ranging from 6 to 10 keV is able to probe a depth of about 8.5 to 12.5 nm with energy resolution of 100 meV. Hard photoelectron spectroscopy are particularly useful for studying the composition and the chemical structure of transition layer at high-k dielectric/silicon interface.

Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

2003 ◽  
Vol 780 ◽  
Author(s):  
C. Essary ◽  
V. Craciun ◽  
J. M. Howard ◽  
R. K. Singh
Keyword(s):  
Uv Radiation ◽  
Photoelectron Spectroscopy ◽  
Grazing Angle ◽  
X Ray Diffraction ◽  
Metal Thin Films ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force ◽  
Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

scholarly journals Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 558
Author(s):  
Wenhui Zhu ◽  
Caiyun Zhang ◽  
Yali Chen ◽  
Qiliang Deng
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Degradation Rate ◽  
Model Compound ◽  
Vibrating Sample Magnetometer ◽  
Simulated Sunlight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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