[DE] VERFAHREN ZUR HERSTELLUNG VON QUARTÄREN AMMONIUM-VERBINDUNGEN [EN] METHOD FOR PRODUCING QUATERNARY AMMONIUM COMPOUNDS [FR] PROCÉDÉ DE PRODUCTION DE COMPOSÉS D'AMMONIUM QUATERNAIRES
Method for Producing Quaternary Ammonium Compounds
申请人:Szarvas Laszlo
公开号:US20070254822A1
公开(公告)日:2007-11-01
The present invention relates to a process for preparing quaternary ammonium compounds, which comprises reacting compounds comprising an sp
3
-hybridized nitrogen atom with a dialkyl sulfate or trialkyl phosphate and subjecting the resulting ammonium compound to an anion exchange.
A semiconductor polishing composition is disclosed. The composition includes fumed silica, the semiconductor polishing composition being an aqueous dispersion solution of fumed silica. A content of the fumed silica includes a particle diameter of 100 nm or less is 15% by volume or more based on a total amount of the fumed silica.
Semiconductor polishing composition
申请人:Ohta Yoshiharu
公开号:US20100090159A1
公开(公告)日:2010-04-15
A semiconductor polishing composition is provided that can, in at least one embodiment, efficiently polish a semiconductor device with high accuracy while preventing fumed silica from being agglomerated and without causing a polishing flaw in the semiconductor device. Fumed silica, of which a bulk density of powder before dispersed is 50 g/L or more and less than 100 g/L, is used as abrasive grains. This makes it possible to enhance a dispersion state of the fumed silica, and to realize reduction in transportation cost.
SILICA FOR CMP, AQUEOUS DISPERSION, AND PROCESS FOR PRODUCING SILICA FOR CMP
申请人:TOKUYAMA CORPORATION
公开号:US20160177155A1
公开(公告)日:2016-06-23
To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m
2
/g or more and 180 m
2
/g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm
3
or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.