Plasma Etching of Hydrogen-Silsesquioxane

1998 ◽  
Vol 511 ◽  
Author(s):  
Youfan Liu ◽  
Chris McMillan ◽  
Fred Dall
Keyword(s):  
Dielectric Constant ◽  
Plasma Etching ◽  
Photoelectron Spectroscopy ◽  
Etching Rate ◽  
Silicon Substrates ◽  
Hydrogen Silsesquioxane ◽  
Xps Spectra ◽  
X Ray ◽  
Lower Dielectric Constant ◽  
Fluorocarbon Polymer

ABSTRACTCF4 plasma etching of hydrogen-silsesquioxane films on bare silicon substrates was conducted. An increase in average etching rate and a decrease in dielectric constant from 2.9 to 2.7 were observed after a top layer was removed from the surface of the film, indicating that a negative density depth gradient in the film was developed during the cure processing, A small part of the reduction in dielectric constant may be attributed to structural change resulting from the plasma interaction with the films since a small amount of Si-F bonds were identified in the surface layer of the film after plasma etching. There are indications in the x-ray photoelectron spectroscopy (XPS) spectra that traces of fluorocarbon polymer residue have been generated during the plasma etching. The results of this study also indicate a possibility of obtaining a lower dielectric constant HSQ film by plasma etching.

Chemical Topography of Si Etching in a Cl2 Plasma, Studied by X-RAY Photoelectron Spectroscopy and Laser-Induced Thermal Desorption

1993 ◽  
Vol 334 ◽  
Author(s):  
V. M. Donnelly ◽  
K. V. Guinn ◽  
C. C. Cheng ◽  
I. P. Herman
Keyword(s):  
Thermal Desorption ◽  
Plasma Etching ◽  
Discharge Tube ◽  
Photoelectron Spectroscopy ◽  
Etching Rate ◽  
Laser Induced Fluorescence ◽  
Xps Analysis ◽  
X Ray ◽  
Si Films ◽  
Positive Ion

AbstractThis paper describes x-ray photoelectron spectroscopy (XPS) studies of etching of Si in high-density Cl2 plasmas. Polycrystalline Si films, masked with photoresist stripes, are etched and then transferred in vacuum to the XPS analysis chamber. Shadowing of photoelectrons by adjacent stripes and differential charging of the photoresist and poly-Si were used to separate contributions from the top of the mask, the side of the mask, the etched poly-Si sidewall, and the bottom of the etched trench. In pure Cl2 plasmas, surfaces are covered with about one monolayer of Cl. If oxygen is introduced into the plasma, either by addition of O2 or by erosion of the glass discharge tube, then a thin Si-oxide layer forms on the sides of both the poly-Si and the photoresist. Laser-induced thermal desorption (LITD) was used to study etching in real time. LITD of SiCI was detected by laser-induced fluorescence. These studies show that the Si-chloride layer formed during plasma etching is stable after the plasma is extinguished, so the XPS measurements are representative of the surface during etching. LITD measurements as a function of pressure and discharge power show that the etching rate is limited by the positive ion flux to the surface, and not by the supply of Cl2, at pressures above 0.5 mTorr and for ion fluxes of σ4× 1016cm−2 s−1.

Epitaxial Graphene Elaborated on 3C-SiC(111)/Si Epilayers

2010 ◽  
Vol 645-648 ◽  
pp. 585-588 ◽  
Author(s):  
Abdelkarim Ouerghi ◽  
Marc Portail ◽  
A. Kahouli ◽  
L. Travers ◽  
Thierry Chassagne ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Low Cost ◽  
Near Field ◽  
Silicon Substrates ◽  
Xps Spectra ◽  
X Ray ◽  
Graphene Layers ◽  
Surface Reconstructions ◽  
High Level ◽  
Modification Of The Surface

This article explores the formation of graphene layers on 3C-SiC(111) epilayers grown on silicon substrates using thermal annealing under Ultra High Vaccum (UHV) environment. The formation of graphene is demonstrated by use of near field microscopy (STM and AFM) and X-ray Photoelectron Spectroscopy (XPS). The evolution of the surface stoichiometry of the 3C-SiC(111) pseudo substrates during the graphitization process is similar to that of the commonly used Si terminated -SiC bulk substrates, starting from a Si rich to the C rich surface characterized by a diffraction pattern. Graphitization process leads to a strong modification of the surface at a microscopic scale which is compared to that reported in case of 6H-SiC substrates. XPS spectra reveal the presence of typical C-C bonds related to a graphitic arrangement. Its high level of ordering is attested by the observation both of (66)SiC and (11)graphene surface reconstructions by STM. These results demonstrate the formation of graphene on 3C-SiC(111)/Si pseudo substrates. They open perspectives for developing novel C/SiC/Si heterostructures and put light on the ability of 3C-SiC/Si templates to become a low cost alternative of onerous -SiC substrates.

scholarly journals Study on the Electrical, Structural, Chemical and Optical Properties of PVD Ta(N) Films Deposited with Different N2 Flow Rates

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 937
Author(s):  
Yingying Hu ◽  
Md Rasadujjaman ◽  
Yanrong Wang ◽  
Jing Zhang ◽  
Jiang Yan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Optical Properties ◽  
Photoelectron Spectroscopy ◽  
Crystal Size ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Dc Magnetron Sputtering ◽  
Flow Rates ◽  
X Ray ◽  
N2 Flow Rate

By reactive DC magnetron sputtering from a pure Ta target onto silicon substrates, Ta(N) films were prepared with different N2 flow rates of 0, 12, 17, 25, 38, and 58 sccm. The effects of N2 flow rate on the electrical properties, crystal structure, elemental composition, and optical properties of Ta(N) were studied. These properties were characterized by the four-probe method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). Results show that the deposition rate decreases with an increase of N2 flows. Furthermore, as resistivity increases, the crystal size decreases, the crystal structure transitions from β-Ta to TaN(111), and finally becomes the N-rich phase Ta3N5(130, 040). Studying the optical properties, it is found that there are differences in the refractive index (n) and extinction coefficient (k) of Ta(N) with different thicknesses and different N2 flow rates, depending on the crystal size and crystal phase structure.

scholarly journals Optical, XPS and XRD Studies of Semiconducting Copper Sulfide Layers on a Polyamide Film

2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Valentina Krylova ◽  
Mindaugas Andrulevičius
Keyword(s):  
Photoelectron Spectroscopy ◽  
Copper Sulfide ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
Xps Spectra ◽  
X Ray ◽  
Xrd Studies ◽  
Polyamide Film ◽  
Indirect Band Gap ◽  
Xrd Method

Copper sulfide layers were formed on polyamide PA 6 surface using the sorption-diffusion method. Polymer samples were immersed for 4 and 5 h in 0.15 mol⋅  solutions and acidified with HCl (0.1 mol⋅) at . After washing and drying, the samples were treated with Cu(I) salt solution. The samples were studied by UV/VIS, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) methods. All methods confirmed that on the surface of the polyamide film a layer of copper sulfide was formed. The copper sulfide layers are indirect band-gap semiconductors. The values of are 1.25 and 1.3 eV for 4 h and 5 h sulfured PA 6 respectively. Copper XPS spectra analyses showed Cu(I) bonds only in deeper layers of the formed film, while in sulfur XPS S 2p spectra dominating sulfide bonds were found after cleaning the surface with ions. It has been established by the XRD method that, beside , the layer contains as well. For PA 6 initially sulfured 4 h, grain size forchalcocite, , was  nm and fordjurleite, , it was 54.17 nm. The sheet resistance of the obtained layer varies from 6300 to 102 .

Effect of Surface Chemistry on Ruthenium Wet Etching

2021 ◽  
Vol 314 ◽  
pp. 302-306
Author(s):  
Quoc Toan Le ◽  
E. Kesters ◽  
M. Doms ◽  
Efrain Altamirano Sánchez
Keyword(s):  
Surface Roughness ◽  
Photoelectron Spectroscopy ◽  
Etching Rate ◽  
Wet Etching ◽  
X Ray ◽  
Force Microscopy ◽  
Metal Free ◽  
Atomic Force ◽  
Different Types ◽  
Effect Of Surface

Different types of ALD Ru films, including as-deposited, annealed Ru, without and with a subsequent CMP step, were used for wet etching study. With respect to the as-deposited Ru, the etching rate of the annealed Ru film in metal-free chemical mixtures (pH = 7-9) was found to decrease substantially. X-ray photoelectron spectroscopy characterization indicated that this behavior could be explained by the presence of the formation of RuOx (x = 2,3) caused by the anneal. A short CMP step applied to the annealed Ru wafer removed the surface RuOx, at least partially, resulting in a significant increase of the etching rate. The change in surface roughness was quantified using atomic force microscopy.

29Si NMR and XPS Investigation of the Structure of Silicon Oxycarbide Glasses Derived from Polysiloxane Precursors

1994 ◽  
Vol 346 ◽  
Author(s):  
R.J.P. Corriu ◽  
D. Leclercq ◽  
P.H. Mutin ◽  
A. Vioux
Keyword(s):  
Solid State ◽  
Photoelectron Spectroscopy ◽  
Solid State Nmr ◽  
Random Distribution ◽  
Silicon Oxycarbide ◽  
29Si Nmr ◽  
Xps Spectra ◽  
Excess Carbon ◽  
X Ray ◽  
Silicon Oxycarbide Glasses

ABSTRACTTwo silicon oxycarbide glasses with different compositions (O/Si ratio 1.2 and 1.8) were prepared by pyrolysis at moderate temperature (900 °C) of polysiloxane precursors. Their structure was investigated using quantitative 29Si solid-state NMR and X-ray photoelectron spectroscopy (XPS). The environment of the silicon atoms in the oxycarbide phase corresponded to a purely random distribution of Si-O and Si-C bonds depending on the O/Si ratio of the glass only and not on the structure of the precursors. At the light of the NMR results, the Si2p XPS spectra of the glasses may be interpreted using the contribution of the five possible SiOxC4-x tetrahedra. The Cls spectra of these glasses indicated the presence of oxycarbide carbon in CSi4 tetrahedra, similar to carbide carbon, and graphitic-like excess carbon.

Preparation and Characterization of Ni2+-Montmorillonite/Polyvinyl Alcohol Water-Soluble Nanocomposite Film

2005 ◽  
Vol 13 (8) ◽  
pp. 839-846 ◽  
Author(s):  
Li-Ping Wang ◽  
Yun-Pu Wang ◽  
Fa-Ai Zhang
Keyword(s):  
Polyvinyl Alcohol ◽  
Photoelectron Spectroscopy ◽  
Thermal Characteristics ◽  
Water Soluble ◽  
Scanning Calorimetry ◽  
Xps Spectra ◽  
X Ray ◽  
Alcohol Water ◽  
Ft Ir ◽  
Silicate Layers

A new type of nano-composite film was prepared from polyvinyl alcohol, Ni2+-montmorillonite (Ni2+-MMT), defoamer, a levelling agent and a plasticizer. Its thermal characteristics were studied by Differential Scanning Calorimetry (DSC). The intermolecular interactions were measured by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the tensile strength (TS) and elongation at break (%E) were measured. The microstructures were studied by X-ray diffraction (XRD) and atomic force microscopy (AFM). FT-IR and XPS spectra indicated that cross-linking has taken place between PVA and Ni2+-MMT. XRD and AFM indicate that the PVA molecules had inserted themselves into the silicate layers of MMT, exfoliating them and dispersing them randomly into the PVA matrix. Compared to pure PVA film, the TS of the films was increased and %E decreased when the Ni2+-Montmorillonite was added and the dissolution temperature of the film was also reduced.

scholarly journals Influence of the Microstructure and Optical Constants on Plasmonic Properties of Copper Nanolayers

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7292
Author(s):  
Tomasz Rerek ◽  
Beata Derkowska-Zielinska ◽  
Marek Trzcinski ◽  
Robert Szczesny ◽  
Mieczyslaw K. Naparty ◽  
...  
Keyword(s):  
Surface Plasmon ◽  
Photoelectron Spectroscopy ◽  
Surface Plasmon Polariton ◽  
Optical Constants ◽  
Localized Surface Plasmon ◽  
Silicon Substrates ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Plasmon Polariton

Copper layers with thicknesses of 12, 25, and 35 nm were thermally evaporated on silicon substrates (Si(100)) with two different deposition rates 0.5 and 5.0 Å/s. The microstructure of produced coatings was studied using atomic force microscopy (AFM) and powder X-ray diffractometer (XRD). Ellipsometric measurements were used to determine the effective dielectric functions <ε˜> as well as the quality indicators of the localized surface plasmon (LSP) and the surface plasmon polariton (SPP). The composition and purity of the produced films were analysed using X-ray photoelectron spectroscopy (XPS).

scholarly journals Following excited-state chemical shifts in molecular ultrafast x-ray photoelectron spectroscopy

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
D. Mayer ◽  
F. Lever ◽  
D. Picconi ◽  
J. Metje ◽  
S. Alisauskas ◽  
...  
Keyword(s):  
Excited State ◽  
Chemical Shift ◽  
Photoelectron Spectroscopy ◽  
Chemical Shifts ◽  
Excited Molecule ◽  
Charge Motion ◽  
Core Electron ◽  
Xps Spectra ◽  
X Ray ◽  
State Chemical

AbstractThe conversion of photon energy into other energetic forms in molecules is accompanied by charge moving on ultrafast timescales. We directly observe the charge motion at a specific site in an electronically excited molecule using time-resolved x-ray photoelectron spectroscopy (TR-XPS). We extend the concept of static chemical shift from conventional XPS by the excited-state chemical shift (ESCS), which is connected to the charge in the framework of a potential model. This allows us to invert TR-XPS spectra to the dynamic charge at a specific atom. We demonstrate the power of TR-XPS by using sulphur 2p-core-electron-emission probing to study the UV-excited dynamics of 2-thiouracil. The method allows us to discover that a major part of the population relaxes to the molecular ground state within 220–250 fs. In addition, a 250-fs oscillation, visible in the kinetic energy of the TR-XPS, reveals a coherent exchange of population among electronic states.

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