Abstract: A thick planarization layer of silicon dioxide that is heat resistant is provided by coating a polysilazane layer over a substrate having steps and firing the polysilazane layer in an oxygen-containing atmosphere to convert the polysilazane to silicon dioxide. The temperature of this conversion may be as low as 400.degree. to 450.degree. C. while a higher firing or curing temperature is preferable to obtain a more densified oxide layer.

Abstract: To prepare crystalline sodium disilicates having a laminar structure, a molar ratio of SiO.sub.2 to Na.sub.2 O of (1.9 to 2.1) 1 and a water content of less than 0.3% by weight, a water glass solution is first obtained by reacting sand with sodium hydroxide solution in a molar ratio of SiO.sub.2 to Na.sub.2 O of (2.0 to 2.3) : 1 at temperatures of 180.degree. to 240.degree. C. and pressures of 10 to 30 bar. This water glass solution having at least 20% by weight of solids is treated in a spray drier with hot air at 200.degree. to 300.degree. C. with the formation of a pulverulent amorphous sodium disilicate having a water content (determined as loss on heating at 700.degree. C.) of 15 to 23% by weight and a bulk density of at least 300 g/l. The spray-dried pulverulent, amorphous sodium disilicate is ground.

Abstract: A selective sidewall diffusion process using doped SOG. A substrate is processed to form raised portions or pedestals, having sidewalls, and trenches. A first layer, either a doped SOG layer or undoped oxide layer, may be deposited onto the substrate adjacent the sidewalls. The first layer is densified. A second layer may be deposited on the first layer. The second layer is a doped SOG layer. The second layer is densified and the dopant is driven into the sidewalls to form shallow junctions.

Abstract: A ceramic product comprising both carbon and nitrogen and a method for its production are provided. The product is formed in a reactor having a chamber defined therein which is divided into a combustion zone and a reaction zone. A combustible mixture is injected into the combustion zone in a direction generally toward the reaction zone, and is accordingly combusted in the combustion zone to produce hot combustion products. At least one reactant containing carbon, nitrogen and an additional component (i.e. silicon) is injected at the boundary between the zones into the reactor chamber so as to flow with the hot combustion products into the reaction zone and react to form the ceramic product.

Abstract: The invention provides a process for the production of a high grade amorphous silica having a purity of at least 90% active silica of the formula SiO.sub.2.nH.sub.2 O, comprising the steps of:a. comminuting and wet classification of porcellanite rock to form granules having an average diameter of 200 microns to 8 mm;b. combining the resulting granules with NaOH at a temperature of up to 100.degree. C. to form a product containing sodium silicates;c. separating a liquid containing the sodium silicates from solid waste;d. adding CO.sub.2 to the liquid product to form SiO.sub.2.nH.sub.2 O and Na.sub.2 CO.sub.3 ;e. washing the resulting product to effect a separation of the precipitated SiO.sub.2.nH.sub.2 O from the soluble Na.sub.2 CO.sub.3 ; andf. recovering SiO.sub.2.nH.sub.2 O of a purity of at least 90%.

Abstract: A differentiable ablation approach to patterning dielectrics which are not of the same absorbance uses an absorbant dielectric at a specified laser wavelength over a non-absorbant dielectric at that wavelength. The absorbant dielectric may be laser-patterned and become an integral mask enabling plasma etching of the underlying non-absorbant dielectric. If the patterning of the absorbant dielectric involves vias, polymer ridges formed around via surfaces during laser patterning may be removed at the same time the underlying non-absorbant dielectric is etched using a transparent, oxygen plasma resistant mask. Alternatively, an inert mask may be used instead of the absorbant dielectric to allow plasma etching of the non-absorbant dielectric.

Abstract: A method for manufacturing semiconductor devices according to this invention, comprises the wafer manufacturing step of forming an integrated circuit with a redundant circuit in each of a plurality of chip areas on a semiconductor wafer and also forming at least one stress testing terminal that applies a stress testing voltage or stress testing signal to the interconnections other than those for power supply in the integrated circuit for each of the chip areas or for every certain number of the chip areas, the step of, after the wafer manufacturing step, screening failures by applying a specified stress testing control signal or stress voltage to a certain number of chip areas with the stress testing terminal in contact with a contact terminal of a tester in the wafer state, the step of, after the screening step, judging whether or not the electrical characteristics of each chip area are acceptable through die sort test, the step of remedying an integrated circuit in a chip area judged to be defective in the

Abstract: A method for forming a fine pattern of a semiconductor device, in which a first-to-be-patterned layer is formed on a semiconductor substrate, a photoresist film is coated on the first-to-be-patterned layer, and the photoresist film is patterned and cured to obtain a thermally stable photoresist film pattern. Thereafter, a second material layer is formed on the entire surface of the semiconductor substrate on which the photoresist film pattern is formed, by a low temperature plasma method, and the second material layer is anisotropically etched to thereby form a spacer made of the second material layer on the sidewalls of the photoresist film pattern. A first pattern is formed by anisotropically etching the first-to-be-patterned layer, using the spacer and the photoresist film pattern as an etching mask. The spacer and the photoresist film pattern are then removed. Using the first pattern thus obtained, a fine pattern which is the inverse of the first pattern can be formed.

Abstract: The black powder to be treated is injected into the bottom portion of a heated dense fluidized bed, said bed having effective depth enabling the carbon the particles of silica to be oxidized into carbon dioxide as the particles go through the dense fluidized bed while being entrained by the fluidization air. The whitened powder is then recovered by filtering the gases leaving said dense fluidized bed. The invention is particularly applicable to the cosmetics industry for producing make-up that uses silica powder.

Abstract: A silicon oxide film to be used as an interlayer-insulating film in a semiconductor device is formed by a high pressure organic silane-O.sub.3 CVD. A semiconductor wafer is placed in a reaction vessel and is heated at a temperature of 350.degree. C. A mixture of an organic silane gas such as TEOS, HMDS and OMCTS and an ozone gas is introduced into the reaction vessel and the reaction is carried out at a pressure higher than the atmospheric pressure, preferably at a pressure of about 2 atm to form a silicon oxide film having excellent properties. A life time of the ozone gas which serves as an oxiding agent and/or catalyst can be prolonged under the high pressure, and therefore a deposition rate of the silicon oxide film ca be increased and the flatness of the silicon oxide film can be improved. Therefore, the silicon oxide film forming process can be performed efficiently and a flatening process after the formation of the silicon oxide film can be made simpler.

Abstract: A carbide former is introduced into briquettes in the production of silicon in an electric-arc low-shaft furnace to improve the trapping of silicon oxide rising in the furnace and increase the silicon yield. The carbide former can be calcium, magnesium or aluminum, preferably in the form of the silicate and most advantageous is magnesium silicate.

Abstract: Superconducting or conducting organic charge-transfer complex film is epitaxially grown on a substrate which has been given an oriented surface by applying a stearic acid film. The periodic charge distribution over the oriented surface regulates the formation of the complex film to arrange the molecules along a common axis. The alignment of the molecules in the complex film helps to have superconductivity or high conductivities.

Abstract: The present invention is directed to a method for making substantially carbon-free polycrystalline silicon which comprises pyrolyzing a gaseous silicon compound on a heated starter filament mounted on a graphite chuck, said heated starter filament being maintained at a temperature sufficient to effect decomposition of the gaseous silicon compound to form polycrystalline silicon which is deposited thereon and by-product hydrogen, wherein the said graphite chuck is provided with a hydrogen impervious outer coating layer to prevent the by-product hydrogen from reacting with the graphite and form methane which decomposes as carbon on the deposited polycrystalline silicon.

Abstract: A super heat-resistant silicon carbide fiber has an oxygen content of less than 0.1% by weight. In a process for producing the super heat-resistant silicon carbide fiber, a precursor fiber prepared by spinning a polycarbosilane having an oxygen content of less than 0.8% by weight is irradiated with a radiation in an oxygen-free atmosphere or in vacuo to make the precursor fiber infusible. The infusibilized fiber is fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000.degree. to 2200.degree. C. without exposure to an oxidizing atmosphere; or stabilized in the same atmosphere at a temperature of from 300.degree. to 600.degree. C. without exposure to an oxidizing atmosphere and fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000.degree. to 2200.degree. C.

Abstract: An improved method and apparatus for preparing low-concentration polysilicate microgels from a water soluble silicate and a strong acid in which the silicate and acid are mixed at a rate to produce a Reynolds number of at least 4000, the mixture is aged and then diluted to a silica concentration of not more than 1.0 wt. %.

Abstract: Generally, and in one form of the invention, a method is disclosed for contacting a feature on an integrated circuit comprising: depositing a removable planarizing material 14 around the feature 10 so that a portion of the feature 10 extends above the removable planarizing material 14; depositing a masking layer 18 above the removable planarizing material 14, the masking layer 18 covering all but an exposed region above the feature 10 and an area around the feature; depositing an interconnect contact material 20 on the exposed region; and removing the masking layer 18 and the removable planarizing material 14, leaving the interconnect contact material 20 deposited on the exposed region, whereby a reliable, low capacitance, electrical contact is made to a very small feature 10.

Abstract: The invention relates to dispersions of spherical inorganic particles, organic dispersing media having solidification points in the range of 20.degree.-120.degree. C. being used as dispersants.

Abstract: A two-step method is described for making transparent aerogels which have a density of less than 0.003 g/cm.sup.3 to those with a density of more than 0.8 g/cm.sup.3, by a sol/gel process and supercritical extraction. Condensed metal oxide intermediate made with purified reagents can be diluted to produce stable aerogels with a density of less than 0.02 g/cm.sup.3. High temperature, direct supercritical extraction of the liquid phase of the gel produces hydrophobic aerogels which are stable at atmospheric moisture conditions. Monolithic, homogeneous silica aerogels with a density of less than 0.02 to higher than 0.8 g/cm.sup.3, with high thermal insulation capacity, improved mechanical strength and good optical transparency, are described.

Abstract: There is provided a method for bonding at least two semiconductor wafers to each other which comprises the steps of warping one of the semiconductor wafers, bringing the warped semiconductor wafer into contact with the other semiconductor wafer at one contact point, and reducing pressure in an atmosphere surrounding the semiconductor wafers to flatten the warped semiconductor wafer. An apparatus for bonding wafers using the above bonding method comprises a first wafer holder for warping and holding one of two wafers and a second wafer holder for holding the other wafer. First and second covers are attached so as to surround the first and second wafer holders. The apparatus further comprises a shaft for rotating the first and second wafer holders so that one of the wafers contact the other wafer at one contact point and the first and second covers are connected to each other to form a chamber.

Abstract: Fine particle silica, especially fumed silica (FS), is interacted, in aqueous medium, with a substantially crystalline mixed metal layered hydroxide (MMLH) of the formula shown below to form a novel adduct, MMLH-SiO.sub.2, as an aqueous gell which is shear-thinning and which has rapid gelation times, the said MMLH comprising the general formulaLi.sub.m D.sub.d T(OH)(m+2d+3+n.a)(A.sup.n)a.qH.sub.2 O (I)where: m is from zero to about 1; D represents divalent metal ions; d is from zero to about 4; T represents trivalent metal ions; A represents monovalent or polyvalent anions or negative-valence radicals other than OH-ions; a is the number of ions of A; n is the valence of A; n-a is from zero to about -3; q is zero or more; (m+d) is greater than zero; and (m+2d+3+n.a) is equal to or greater than 3.