Spin-on Silicon Oxide (Sox): Deposition and Properties

1988 ◽  
Vol 131 ◽  
Author(s):  
Gerald Smolinsky ◽  
Vivian Ryan
Keyword(s):  
Refractive Index ◽  
Infrared Spectrum ◽  
Silicon Oxide ◽  
Etching Rate ◽  
Sol Gel ◽  
Solvent System ◽  
Wet Etching ◽  
Curing Temperature ◽  
Rutherford Back Scattering ◽  
Free Films

ABSTRACTHigh quality SiO2 films are obtained by spin-coating wafers with a sol/gel of silicic acid in either a 2, 3, or 4-carbon linear-aliphatic alcohol. Some properties of the deposited film depend upon the solvent: such as density, tensile stress, and infrared spectrum. However, Rutherford-back-scattering analysis indicates the O:Si ratio (2.00±05) to be independent of the solvent. The infrared spectrum of the oxide exhibits Si-OSi absorption in the range 1070–1080 cm.−1 depending on the curing temperature and solvent system. (The weaker Si-OSi band is found at 804–810 cm.−1) In addition, low-temperature-cured (<500 °C) films show Si–OH absorption. Films hot-plate baked at 150–350 °C are stable but not fully cured. Films from propanol baked at 400 °C have a refractive index of 1.41–1.42 and a wet-etching rate in 30:1 BOE of ˜1250 Å/min. Films cured at 900 °C have a refractive index of 1.42–1.43, a wet-etching rate of ˜430 A/min, and are more dense by a factor of ˜1.25. Dry-etching with CHF3/O2 occurs at rates comparable to those of CVD oxides. Multiple applications lead to crack-free films as thick as 0.6–0.8 μ m. Deposition over aluminum-patterned topography results in a smoothing of the surface and suppression of hillock growth in the aluminum even after a 450 °C cure. SOX adheres to silicon, aluminum, and silicon dioxide. A boron-doped SOX is readily prepared.

Perovskite crystallization of sol-gel processed (Pb,La0.06,Gd0.02)(Zr0.65,Ti0.35)O3 thin films: Dielectric, ferroelectric and optical properties

2002 ◽  
Vol 17 (10) ◽  
pp. 2652-2659 ◽  
Author(s):  
Reji Thomas ◽  
Shoichi Mochizuki ◽  
Toshiyuki Mihara ◽  
Tadashi Ishida
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Sol Gel ◽  
Band Gap Energy ◽  
Elemental Distribution ◽  
Surface And Interface ◽  
Si Substrates ◽  
Dielectric Constant And Loss ◽  
Direct Band ◽  
Free Films

Ferroelectric lead lanthanum gadolinium zirconium titanate (PLGZT) thin films were prepared by the sol-gel spin coating technique. Three-step preannealing heat treatment was employed to prepare crack-free films. Various types of substrates, and the effects of the seed layer and annealing temperature on the perovskite crystallization were studied. Phase-pure perovskite crystallization was obtained by annealing the films on PbTiO3/Pt/Ti/Si substrates at 700 °C for 30 min. The Auger electron spectroscopy depth profile showed uniform elemental distribution along the thickness except the surface and interface regions. Dielectric constant and loss tangent at 10 kHz were 1000 and 0.06, respectively. Remanent polarization (Pr) and coercive field (Ec) were 11.8 μC/cm2 and 71 kV/cm, respectively. The direct band gap energy was 3.55 eV for the amorphous films. The refractive index and extinction coefficient at 610 nm for amorphous PLGZT films were 2.14 and 0.0028, respectively. The dispersion of the refractive index was interpreted in terms of a single electronic oscillator at 6.06 eV.

Effect of Electrochemical Reaction Enviroment on the Surface Morphology and Photoluminescence of Porous Silicon

2013 ◽  
Vol 737 ◽  
pp. 60-66
Author(s):  
Ali Syari’ati ◽  
Veinardi Suendo
Keyword(s):  
Porous Silicon ◽  
Surface Morphology ◽  
Silicon Oxide ◽  
Quantum Confinement Effect ◽  
Etching Rate ◽  
Green Emission ◽  
Wet Etching ◽  
Electrochemical Anodization ◽  
Etching Method ◽  
Silicon Based

Porous silicon (p-Si) is a well-known silicon based material that can emit visible light at room temperature. The radiative recombination that originated from quantum confinement effect shows photoluminescence (PL) in red, while the defect on silicon oxide at the surface of p-Si shows in blue-green region. Porous silicon can be synthesized through two methods; wet-etching and electrochemical anodization using hydrofluoric acid as the main electrolyte. The electrochemical anodization is more favorable due to faster etching rate at the surface than the conventional wet-etching method. The objective of this research is to show that both of porous silicons can be synthesized using the same main electrolyte but by varying the reaction environment during anodization/etching process. Here, we shows the wet-etching method that enhanced by polarization concentration will produce porous silicon with silicon oxide defects by means blue-green emission, while direct electrochemical anodization will produce samples that emit red PL signal. The effect of introducing KOH into the electrolyte was also studied in the case of enhanced-wet-etching method. Surface morphology of porous silicon and their photoluminescence were observed by Scanning Electron Microscope and PL spectroscopy, respectively.

Spin-on Silicon Oxide (SOX): Physical Properties of the Sol

1988 ◽  
Vol 131 ◽  
Author(s):  
Vivian Ryan ◽  
Gerald Smolinsky
Keyword(s):  
Physical Properties ◽  
Silicon Oxide ◽  
Particle Density ◽  
Etching Rate ◽  
Particle Diameter ◽  
Particle Growth ◽  
Wet Etching ◽  
Aggregation Kinetics ◽  
Average Particle ◽  
Concentration Changes

ABSTRACTThis paper describes an analysis of the physical properties of the sol using several complementary light scattering techniques. Polymerization and aggregation kinetics were followed through time-dependent changes in the size, shape, and density of the sol particles. The sot growth rate was controlled by choice of solvent and silicon concentration. Changes in viscosity and pH were small during the reaction period. Three different particle-growth regimes exist in which either the particle density increased, decreased, or remained the same. The addition of boron, hydrofluoric acid, or water accelerated the reaction. The sol experimental data correlate with the density and wet-etching rate of the cured films. After curing, high-density films were obtained from sols with three common characteristics: an average particle diameter >450 Å, a relatively high polydispersity, and a low particle density. These criteria were generally satisfied by solutions one to two days old.

Sol-Gel Derived Polyvinylpyrrolidone/Silicon Oxide Composite Materials and Novel Fabrication Technique for Channel Waveguide

1995 ◽  
Vol 392 ◽  
Author(s):  
Makoto Yoshida ◽  
Paras N. Prasad
Keyword(s):  
Thermal Decomposition ◽  
Refractive Index ◽  
Composite Materials ◽  
Silicon Oxide ◽  
Sol Gel ◽  
Propagation Loss ◽  
Slab Waveguides ◽  
Optical Propagation ◽  
Laser Densification ◽  
Channel Waveguides

AbstractSol-gel derived composite materials of polyvinylpyrrolidone (PVP), SiO2 and TiO2 were studied to achieve low optical propagation loss and high thermal stability in slab waveguides. PVP is a thermally crosslinkable polymer. However, the thermal crosslinking and thermal decomposition take place around the same temperature, 200 °C, resulting in high optical propagation loss. The incorporation of sol-gel processed SiO2 prevents thermal decomposition of PVP and produces remarkably low optical propagation loss even after being baked at 230 °C. We have achieved 0.2 dB/cm optical propagation loss at 633 nm. Furthermore, little index change was observed at 110 °C for 1,000 hours after initial slight increase. Impregnation of sol-gel processed TiO2 into the PVP/SiO2 system was also studied to increase refractive index. A broad manipulation of refractive index, from 1.49 to 1.65, with an optical propagation loss of less than 0.6 dB/cm at 633 nm was accomplished by a careful selection of Ti alkoxide and optimized reaction conditions. PVP/SiO2 slab waveguides were then used to fabricate channel waveguides by using a laser densification technique utilizing metal lines as light absorbent and an Ar laser. An optical propagation loss of 0.9 dB/cm was achieved at 633 nm.

scholarly journals Synthesis and Characterization of Mixed Metal Oxide Nanocomposite Energetic Materials

2003 ◽  
Vol 800 ◽  
Author(s):  
Brady J. Clapsaddle ◽  
Lihua Zhao ◽  
Alex E. Gash ◽  
Joe H. Satcher ◽  
Kenneth J. Shea ◽  
...  
Keyword(s):  
Mass Transport ◽  
Metal Oxide ◽  
Energetic Materials ◽  
Silicon Oxide ◽  
Sol Gel ◽  
Synthesis And Characterization ◽  
Mixed Metal Oxide ◽  
Organic Additives ◽  
Metal Oxide Silicon

ABSTRACTIn the field of composite energetic materials, properties such as ingredient distribution, particle size, and morphology, affect both sensitivity and performance. Since the reaction kinetics of composite energetic materials are typically controlled by the mass transport rates between reactants, one would anticipate new and potentially exceptional performance from energetic nanocomposites. We have developed a new method of making nanostructured energetic materials, specifically explosives, propellants, and pyrotechnics, using sol-gel chemistry. A novel sol-gel approach has proven successful in preparing metal oxide/silicon oxide nanocomposites in which the metal oxide is the major component. Two of the metal oxides are tungsten trioxide and iron(III) oxide, both of which are of interest in the field of energetic materials. Furthermore, due to the large availability of organically functionalized silanes, the silicon oxide phase can be used as a unique way of introducing organic additives into the bulk metal oxide materials. As a result, the desired organic functionality is well dispersed throughout the composite material on the nanoscale. By introducing a fuel metal into the metal oxide/silicon oxide matrix, energetic materials based on thermite reactions can be fabricated. The resulting nanoscale distribution of all the ingredients displays energetic properties not seen in its microscale counterparts due to the expected increase of mass transport rates between the reactants. The synthesis and characterization of these metal oxide/silicon oxide nanocomposites and their performance as energetic materials will be discussed.

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.

scholarly journals Selective porous gates made from colloidal silica nanoparticles

2015 ◽  
Vol 6 ◽  
pp. 2105-2112 ◽  
Author(s):  
Roberto Nisticò ◽  
Paola Avetta ◽  
Paola Calza ◽  
Debora Fabbri ◽  
Giuliana Magnacca ◽  
...  
Keyword(s):  
Silica Nanoparticles ◽  
Spin Coating ◽  
Colloidal Silica ◽  
Sol Gel ◽  
Chemical Species ◽  
Solvent System ◽  
Porous Films ◽  
Nanoporous Films ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Highly selective porous films were prepared by spin-coating deposition of colloidal silica nanoparticles on an appropriate macroporous substrate. Silica nanoparticles very homogenous in size were obtained by sol–gel reaction of a metal oxide silica precursor, tetraethyl orthosilicate (TEOS), and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as soft-templating agents. Nanoparticles synthesis was carried out in a mixed solvent system. After spin-coating onto a macroporous silicon nitride support, silica nanoparticles were calcined under controlled conditions. An organized nanoporous layer was obtained characterized by a depth filter-like structure with internal porosity due to interparticle voids. Permeability and size-selectivity were studied by monitoring the diffusion of probe molecules under standard conditions and under the application of an external stimulus (i.e., electric field). Promising results were obtained, suggesting possible applications of these nanoporous films as selective gates for controlled transport of chemical species in solution.

Preparation and characterization of acrylic polymer titania hybrid. A study of organicinorganic interactions in hybrid materials by micro-hardness Vickers

2002 ◽  
Vol 726 ◽  
Author(s):  
Van Nhan Nguyen ◽  
François Xavier Perrin ◽  
Jean-Louis Vernet
Keyword(s):  
Mechanical Properties ◽  
Large Scale ◽  
Sol Gel ◽  
Mechanical Analysis ◽  
Polymer Chains ◽  
Segmental Motion ◽  
Acrylic Polymer ◽  
Titania Content ◽  
Mineral Constituent ◽  
Free Films

AbstractMetal-oxide ceramer films have been developed using an acrylic polymer bearing a low amount of methacrylic acid units (ca. 4%mol) as the organic phase with titanium tetrabutoxide as the inorganic sol-gel precursor. The characterisation of free films was realized by various experimental methods. The formation of COOTi bonds prevents large scale phase separation between the organic component and the mineral network. Mechanical properties of the hybrid films have been investigated through dynamic mechanical analysis. The influence of the titania content on the damping peak amplitude suggests that titania is molecularly dispersed in the polymer matrix and that it significantly hinders the segmental motion of the polymer chains. However, the low content in potential carboxylic crosslinking sites explains why the glass transition temperature remains relatively unchanged when titania content increases. Vickers microhardness measurements used in this study allowed us to understand the contribution of the inorganic part (phase TiO2) to the mechanical properties of the polymer. The creep of hybrids has been studied carrying out hardness measurements under various indentation times. The mineral constituent leads to an important increase of the hardness and limits, in a significant way, the creep of polymer.

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