摘要:
In the present invention, alumina is produced by a process comprising leading a starting aqueous slurry containing a seed alumina hydrate to a circulating system, the aqueous slurry being circulated and returned to the starting aqueous slurry, wherein an aqueous solution of an aluminum salt and an aqueous solution of a neutralizer are added to the aqueous slurry being circulated and mixed together at a pH value of 6 to 11 to thereby cause the aqueous slurry to contain formed alumina hydrate prior to the return to the starting aqueous slurry. The production of alumina is performed in an apparatus comprising a vessel equipped with an agitator for accommodating an aqueous slurry therein and a circulating device capable of leading the aqueous slurry outside the vessel and causing the aqueous slurry to circulate and return into the vessel, the above circulating device being provided at its aqueous slurry flowback zone with a first liquid addition device adapted to add an aqueous solution of an aluminum salt to the aqueous slurry being circulated and with a second liquid addition device adapted to add an aqueous solution of a neutralizer to the aqueous slurry being circulated, which apparatus further comprises a mixer adapted to mix together the aqueous slurry being circulated, the aqueous solution of the aluminum salt and the aqueous solution of the neutralizer.
摘要:
Disclosed is a coating liquid for forming an amorphous silica-based coating film having a low dielectric constant of 3.0 or below and low leakage current, and a method for preparing the coating liquid. The coating liquid is a liquid composition comprising (a) silicon compound obtained by hydrolyzing tetraalkyl orthosilicate (TAOS) and alkoxysilane (AS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, or a silicon compound obtained by hydrolyzing or partially hydrolyzing tetraalkyl orthosilicate (TAOS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, mixing the hydrolyzed or partially hydrolyzed product with alkoxysilane (AS) or a hydrolyzed or partially hydrolyzed product thereof, and hydrolyzing all or a portion of the mixture, (b) an organic solvent, and (c) water. The coating liquid is characterized in that a quantity of water contained in the liquid composition is in the range from 30 to 60% by weight.
摘要:
A coating liquid for forming a low dielectric constant amorphous silica-based coating film with a dielectric constant of 3.0 or below and a film strength (Young's modulus) of 3.0 GPa or more, and also having a smooth surface with an excellent hydrophobicity. The coating liquid contains (1) a silicon compound obtained by hydrolyzing bis(trialkoxysilyl)alkane (BTASA) and alkoxysilane (AS) in the presence of tetraalkylammoniumhydroxide (TAAOH), or (2) a silicon compound obtained by hydrolyzing bis(trialkoxysilyl)alkane (BTASA), alkoxysilane (AS) and tetraalkylorthosilicate (TAOS) in the presence of tetraalkylammoniumhydroxide (TAAOH).
摘要:
Disclosed is a coating liquid for forming a protective film having high film strength and a low specific dielectric constant for semiconductor processing, and a method for preparing the coating liquid. The coating liquid is a liquid composition comprising (a) silicon compound obtained by hydrolyzing tetraalkyl orthosilicate (TAOS) and alkoxysilane (AS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, or a silicon compound obtained by hydrolyzing or partially hydrolyzing tetraalkyl orthosilicate (TAOS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, mixing the hydrolyzed or partially hydrolyzed product with alkoxysilane (AS) or a hydrolyzed or partially hydrolyzed product thereof, and hydrolyzing all or a portion of the mixture, (b) an organic solvent, and (c) water. The coating liquid is characterized in that a quantity of water contained in the liquid composition is in the range from 35 to 65% by weight.
摘要:
Disclosed is a coating liquid for forming a protective film having high film strength and a low specific dielectric constant for semiconductor processing, and a method for preparing the coating liquid. The coating liquid is a liquid composition comprising (a) silicon compound obtained by hydrolyzing tetraalkyl orthosilicate (TAOS) and alkoxysilane (AS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, or a silicon compound obtained by hydrolyzing or partially hydrolyzing tetraalkyl orthosilicate (TAOS) in the presence of tetraalkyl ammonium hydroxide (TAAOH) and water, mixing the hydrolyzed or partially hydrolyzed product with alkoxysilane (AS) or a hydrolyzed or partially hydrolyzed product thereof, and hydrolyzing all or a portion of the mixture, (b) an organic solvent, and (c) water. The coating liquid is characterized in that a quantity of water contained in the liquid composition is in the range from 35 to 65% by weight.
摘要:
A coating liquid for forming a low dielectric constant amorphous silica-based coating film with a dielectric constant of 3.0 or below and a film strength (Young's modulus) of 3.0 GPa or more, and also having a smooth surface with an excellent hydrophobicity. The coating liquid contains (1) a silicon compound obtained by hydrolyzing bis(trialcoxysilyl)alkane (BTASA) and alcoxysilane (AS) in the presence of tetraalkylammoniumhydroxide (TAAOH), or (2) a silicon compound obtained by hydrolyzing bis(trialcoxysilyl)alkane (BTASA), alcoxysilane (AS) and tetraalkylorthosilicate (TAOS) in the presence of tetraalkylammoniumhydroxide (TAAOH).