Cleaning and Oxidation of Heavily Doped Si Surfaces

1992 ◽  
Vol 259 ◽  
Author(s):  
T. Yasaka ◽  
S. Uenaga ◽  
H. Yasutake ◽  
M. Takakura ◽  
S. Miyazaki ◽  
...  
Keyword(s):  
Growth Rate ◽  
Steric Hindrance ◽  
Photoelectron Spectroscopy ◽  
Oxidation Rate ◽  
Electron Tunneling ◽  
Pure Water ◽  
Native Oxide ◽  
Layer By Layer ◽  
Surface Electric Field ◽  
Heavily Doped

ABSTRACTHF-treated Si surfaces and the oxidation kinetics in pure water or in clean room air have systematically been studied by x-ray photoelectron spectroscopy (XPS). The oxidation of heavily-doped n-type Si appears to proceed parallel to the surface, resulting in the layer-by-layer oxidation. The oxide growth rate in pure water for heavily-doped n-type Si is significantly higher than that of heavily-doped ptype Si. This is explained by the electron tunneling from the Si conduction band to adsorbed O2 molecules to form the O2 state. O2 ions easily decompose and induce a surface electric field, enhancing the oxidation rate. The growth rate of native oxide on heavily-doped n-type Si is less sensitive to the crystallographic orientations than the case of lightly doped Si where the steric hindrance against oxygen molecules significantly lowers the oxidation rate of the (110) and (111) surfaces. We suggest that the decomposed oxygen can penetrate into Si without steric hindrance. It is also found that the oxidation of heavily-doped n-type Si in pure water is effectively suppressed by adding a small amount (10 ∼ 3600 ppm) of HCI.

Layer-by-Layer Oxidation of Silicon

1991 ◽  
Vol 222 ◽  
Author(s):  
T. Yasaka ◽  
M. Takakura ◽  
S. Miyazaki ◽  
M. Hirose
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxidation Rate ◽  
Pure Water ◽  
Oxygen Adsorption ◽  
Native Oxide ◽  
Oxide Growth ◽  
Layer By Layer ◽  
X Ray ◽  
P Type ◽  
Kinetics Of

ABSTRACTGrowth kinetics of native oxide on HF-treated Si surfaces terminated with Si-H bonds has been studied by angle-resolved x-ray photoelectron spectroscopy. The oxide growth rate in pure water for an n+ Si(100) surface is significantly high compared to that of p+, and the n or p type Si oxidation rate is in between. This is explained by the formation of ions through electron transfer from Si to adsorbed O2 molecules and the resulting enhancement of the oxidation rate. The oxide growth on Si(100) is faster than (110) and (111) as interpreted in terms of the steric hindrance for molecular oxygen adsorption on the hydrogen terminated silicon 1×1 surface structures.

Chemical Structure of Native Oxide Grown on Hydrogenterminated Silicon Surfaces

1992 ◽  
Vol 259 ◽  
Author(s):  
M. Takakura ◽  
T. Yasaka ◽  
S. Miyazaki ◽  
M. Hirose
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chemical Structure ◽  
Pure Water ◽  
Silicon Surfaces ◽  
Native Oxide ◽  
Appreciable Amount ◽  
X Ray ◽  
Thermal Oxide ◽  
Phonon Peak ◽  
Strained Bonds

ABSTRACTChemical bonding features and suboxide compositions in native oxide grown on chemically-cleaned hydrogen-terminated Si(100) surfaces stored in pure water have been studied by using surface sensitive infrared spectroscopy and x-ray photoelectron spectroscopy. The LO phonon peak for the native oxide is located at 1210cm−1, which is shifted to a significantly lower wavenumber side than the ultrathin thermal oxide peak at 1250cm−1. This is because an appreciable amount of SiHx bonds are incorporated in the native oxide/Si interface and such hydrogen termination in the network dramatically reduces strained bonds in the interface. Very weak Si2+ suboxide signal from the oxide grown in pure water is also explained by the incorporated SiHx bonds which interrupt the Si2+ suboxide formation in the interface.

Native Oxide Growth Behavior on Silicon Surface with Various Resistivity in Ultrapure Water and CuF2 Solution

1997 ◽  
Vol 477 ◽  
Author(s):  
Katsuyuki Sekine ◽  
Geun-Min Choi ◽  
Yuji Saito ◽  
Tadahiro Ohmi
Keyword(s):  
Photoelectron Spectroscopy ◽  
Silicon Surface ◽  
Pure Water ◽  
Oxide Thickness ◽  
Growth Behavior ◽  
Native Oxide ◽  
Oxide Growth ◽  
Ultrapure Water ◽  
Relationship Of ◽  
The Relationship

ABSTRACTWe have studied native oxide growth behavior on silicon surface with various resistivity in ultra pure water (UPW), SPM (sulfuric acid-hydrogen peroxide mixture, H2SO4:H2O2 = 4:1) cleaning and UPW contaminated with CuF2 by X-Ray photoelectron spectroscopy (XPS). The results show that the native oxide growth behavior in UPW is different from that in UPW contaminated with CuF2 and that grown by SPM cleaning. Native oxide thickness grown in UPW depends on resistivity. Native oxide thickness grown during SPM cleaning has the relationship of steric hinderance effect. However, in CuF2 solution, native oxide thickness is more influenced by the redox reaction between Cu ions and silicon atoms.

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.

Heteroepitaxial Nucleation and Growth of Ge ON Si(100) Surfaces Using Remote Plasma Enhanced Chemical Vapor Deposition

1988 ◽  
Vol 116 ◽  
Author(s):  
R.A. Rudder ◽  
S.V. Hattangady ◽  
D.J. Vitkavage ◽  
R.J. Markunas
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Layer By Layer ◽  
Heteroepitaxial Growth ◽  
Remote Plasma ◽  
Dimensional Growth ◽  
Diffraction Patterns

Heteroepitaxial growth of Ge on Si(100) has been accomplished using remote plasma enhanced chemical vapor deposition at 300*#x00B0;C. Reconstructed surfaces with diffraction patterns showing non-uniform intensity variations along the lengths of the integral order streaks are observed during the first 100 Å of deposit. This observation of an atomically rough surface during the initial stages of growth is an indication of three-dimensional growth. As the epitaxial growth proceeds, the diffraction patterns become uniform with extensive streaking on both the integral and fractional order streaks. Subsequent growth, therefore, takes place in a layer-by-layer, two-dimensional mode. X-ray photoelectron spectroscopy of the early nucleation stages, less than 80 Å, show that there is uniform coverage with no evidence of island formation.

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

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.

scholarly journals Preparation and Characterization of MWCNTs/PVDF Conductive Membrane with Cross-Linked Polymer PVA and Study on Its Anti-Fouling Performance

Membranes ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 703
Author(s):  
Yi Ding ◽  
Zhansheng Guo ◽  
Xinan Dong ◽  
Hong You ◽  
Junxue Mei ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Mass Loss Rate ◽  
Pure Water ◽  
Water Flux ◽  
Membrane Properties ◽  
Elongation Ratio ◽  
Functional Layer ◽  
Conductive Membranes ◽  
Pure Water Flux ◽  
Conductive Membrane

Based on carboxylated multi-walled carbon nanotubes (MWCNTs-COOH), a MWCNTs/PVDF conductive membrane was prepared by a vacuum filtration cross-linking method. The surface compositions and morphology of conductive membranes were studied by X-ray photoelectron spectroscopy and high-resolution field emission scanning electron microscopy, respectively. The effects of cross-linked polymeric polyvinyl alcohol (PVA) on the conductive membrane properties such as the porosity, pore size distribution, pure water flux, conductivity, hydrophilicity, stability and antifouling properties were investigated. Results showed that the addition of PVA to the MWCNTs/PVDF conductive membrane decreased the pure water flux, porosity and the conductivity. However, the hydrophilicity of the modified MWCNTs/PVDF conductive membrane was greatly improved, and the contact angle of pure water was reduced from 70.18° to 25.48° with the addition of PVA contents from 0 wt% to 0.05 wt%. Meanwhile, the conductive membranes with higher content had a relatively higher stability. It was found that the conductive functional layer of the conductive membrane had an average mass loss rate of 1.22% in the 30 min ultrasonic oscillation experiment. The tensile intensity and break elongation ratio of the conductive membrane are improved by the addition of PVA, and the durability of the conductive membrane with PVA was superior to that without PVA added. The electric assisted anti-fouling experiments of modified conductive membrane indicated that compared with the condition without electric field, the average flux attenuation of the conductive membrane was reduced by 11.2%, and the membrane flux recovery rate reached 97.05%. Moreover, the addition of PVA could accelerate the clean of the conductive membranes.

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.

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