摘要:
A silica body useful for forming an optical fiber preform exhibits an ultimate strength of at least 20 MPa at 10 wt. % water loss. The body attains this strength, it is believed, by precipitation of silica at the contact sites of adjacent silica particles, thereby forming neck regions. The resultant network provides the strength to the gel body, such that the body is capable of being dried under more severe conditions than a gel body formed by previous sol-gel methods and is also more robust toward handling. The controlled precipitation is attained by inducing gelation and initiating drying at a pH of about 10.5 or higher, at which silica remains highly soluble. By gelling and drying at this pH level, the solubilized silica appears to precipitate in a controlled manner at the point of contact of adjacent silica particles, since such sites are the minimum free energy sites for precipitation.
摘要:
A method for forming a dielectric oxide layer on selected areas of a substrate is disclosed. The dielectric oxide layer is formed on selected areas of the substrate using a sol process. The substrate has an area of a first material and an area of a second material which is different from the first. The first material is coated with a layer of a first compound. The layer of the first compound has a hydrophobic top surface. The second material is coated with a layer of a second compound. The layer of the second compound has a hydrophilic top surface. A layer of hydrous oxide is formed over the second compound by applying an aqueous sol solution on the surface of the substrate. The substrate is then heated to remove the first compound and the second compound from the surface of the substrate. Thereafter, the substrate with the layer of hydrous oxide thereon, is sintered to form the dielectric oxide layer.
摘要:
The specification describes thin film transistor (TFT) devices with source/drain contacts made by a metallo organic deposition (MOD) method wherein a metallo organic compound/metal particulate mixture is deposited to form a base pattern, and the base pattern is then plated with gold. The porous, relatively high resistance base pattern is thereby converted to a corrosion resistant, low resistance contact. The plating covers the sidewalls of the base pattern, thus allowing the final channel length to be less than the minimum design rule used for depositing the base pattern.
摘要:
An improved siloxane-based composition for use as a low &kgr; dielectric material in integrated circuit applications is provided, the composition exhibiting desirable thermal mechanical stability compared to conventional siloxane-based low-&kgr; compositions. Specifically, the invention provides a modified methylsilsesquioxane composition suitable for higher temperature applications than a composition formed from only methylsilsesquioxane. The modified oligomer is characterized by the pendant group ratio A:B:C, where A represents the percentage of pendant groups that are methyl and is about 13 to about 67, B represents the percentage of pendant groups that are dimethyl and is greater than 0 to about 33, and C represents the percentage of pendant groups that are phenyl and is greater than 0 to about 67. The presence of dimethyl and phenyl pendant groups provides a molecular structure that has improved crack-resistance compared to an all-methyl silsesquioxane. Advantageously, the modified methylsilsesquioxane oligomer is fabricated by a particular technique, involving mixing methyltriethoxysilane monomer, before hydrolysis and condensation, with dimethyldiethoxysilane monomer that has already been partially hydrolyzed and condensed. This technique further improves the thermal mechanical stability of the resultant cured material. For low &kgr; integrated circuit application, a pore generator material is advantageously used to provide a porous final structure.
摘要:
It has been found that in sol-gel processes utilizing TMAH, it is possible to treat a trimethylamine (TRIMA)-containing solution with hydrogen peroxide to form trimethylamine oxide--(CH.sub.3).sub.3 N.sup.+ --O.sup.- (TRIMAO), a water soluble compound which is less volatile and less odorous than TRIMA, and which is capable of being sent to a standard wastewater treatment plant. The hydrogen peroxide is generally added to the TRIMA-containing solution in a H.sub.2 O.sub.2 :TRIMA ratio of at least 3:1, advantageously at least 10:1. Because of the resultant TRIMAO solution's ability to be sent to a standard wastewater treatment facility, improved productivity and lowered expense of the overall fiber fabrication process are obtained. The invention is also suitable for treatment of triethylamine.
摘要翻译:已经发现,在使用TMAH的溶胶 - 凝胶法中,可以用过氧化氢处理含三甲胺(TRIMA)的溶液,形成三甲胺氧化物 - (CH 3)3 N + -O-(TRIMAO),这是一种水溶性化合物, 与TRIMA相比,挥发性低,气味较差,能够被送到标准废水处理厂。 过氧化氢通常以至少3:1,有利地至少10:1的H 2 O 2:TRIMA比加到含TRIMA的溶液中。 由于所得到的TRIMAO解决方案能够被送到标准废水处理设备,因此获得了整个纤维制造工艺的提高的生产率和降低的费用。 本发明也适用于治疗三乙胺。
摘要:
A process for device fabrication and resist materials that are used in the process are disclosed. The resist material contains a polymer in combination with a dissolution inhibitor and a photoacid generator (PAG). The dissolution inhibitor is the condensation reaction product of a saturated polycyclic hydrocarbon compound with at least one hydroxy (OH) substituent and a difunctional saturated linear, branched, or cyclic hydrocarbon compound wherein the functional groups are either carboxylic acid or carboxylic acid chloride groups. The condensation product has at least two polycylic moieties. The polymer optionally has acid labile groups pendant thereto which significantly decrease the solubility of the polymer in a solution of aqueous base. A film of the resist material is formed on a substrate and exposed to delineating radiation. The radiation induces a chemical change in the resist material rendering the exposed resist material substantially more soluble in aqueous base solution than the unexposed portion of the resist material. The image introduced into the resist material is developed using conventional techniques, and the resulting pattern is then transferred into the underlying substrate.
摘要:
A holographic medium uses a photosensitive polymer medium. The shelf life of the photosensitive polymer medium is improved by hermetically sealing the polymer between glass plates. The hermetic seal is designed so that high T.sub.g materials, or solder, can be used as the sealant without damage to the polymer already contained between the plates. The hermetic seal comprises metal foils attached to the plates with the edges thereof extending away from the plates in tab-like fashion. The foils are attached prior to filling the assembly with polymer. After filling, the outer edges of the foil tabs are the sealed with local heating away from the site of the polymer, or crimped using mechanical crimping.
摘要:
Electrical device having a metal surface to at least a portion of which electrical connections are to be made by soldering, and having a coating on said portion which protects it against surface alteration which would tend to render such soldering more difficult but through which coating soldering can be effected, said coating comprising a polymer of at least one methacrylate of the general formula ##STR1## wherein R is selected from the group comprising alkyl radicals having from 1-6 carbon atoms and a glycidyl radical.
摘要:
A photorecording medium contains a polymeric matrix, typically cross-linked to provide a desired level of physical stability, and a photoimageable system containing a photoactive monomer. Unlike previous polymer media, which tend to contain a substantially homogeneous dispersion of photoimageable system and matrix polymer, the matrix and photoimageable system of the invention are phase separated, yet still exhibit low light scattering such that useful holographic properties are possible.
摘要:
A reflective element, such as a mirror, includes a substrate and a reflective layer formed thereon. The substrate comprises at least one thixotropic metal alloy, which is injected into a mold to form the shape desired for the reflective element. The reflective element may also include an interface layer comprising a thermoset material, such as an epoxy resin, formed between the substrate and the reflective layer to increase the smoothness of the substrate.