Chemical mechanical polishing slurry compositions, methods of preparing the same and methods of using the same
View Patent ↗Provided herein are chemical mechanical polishing (CMP) slurries and methods for producing the same. Embodiments of the invention include CMP slurries that include (a) a metal oxide; (b) a quaternary ammonium base; and (c) a fluorinated surfactant. In some embodiments, the fluorinated surfactant is a non-ionic perfluoroalkyl sulfonyl compound. Also provided herein are methods of polishing a polycrystalline silicon surface, including providing a slurry composition according to an embodiment of the invention to a polycrystalline silicon surface and performing a CMP process to polish the polycrystalline silicon surface.
1. A method for polishing a polycrystalline silicon surface, comprising
supplying a slurry composition to a polycrystalline silicon surface, wherein the slurry composition comprises (a) a metal oxide; (b) a quaternary ammonium base; and (c) a non-ionic perfluoroalkyl sulfonyl compound; and performing a CMP process to polish the polycrystalline silicon surface, wherein the non-ionic perfluoroalkyl sulfonyl compound comprises a compound represented by Formula 1:
CF 3 (CF 2 ) n SO 2 X (1)
wherein n is an integer from 1 to about 20;
X is selected from the group consisting of COOR, OR, (OCH 2 CH 2 ) m OCH 2 CH 3 and (OCH 2 CH(OH)CH 2 ) m OCH 2 CH(OH)CH 3 ;
R is a C 1-20 alkyl group;
and m is an integer from 1 to about 100.
2. The method of claim 1 , wherein the fluorinated surfactant is present in an amount in a range of about 0.001% to 1% by weight, based on the total weight of the slurry composition.
3. The method of claim 1 , wherein the metal oxide comprises at least one compound selected from the group consisting of SiO 2 , Al 2 O 3 , CeO 2 , ZrO 2 and TiO 2 .
4. The method of claim 1 , wherein the metal oxide has a primary particle size in a range of about 10 nm to about 200 nm and specific surface area in a range of about 10 to about 300 m 2 /g.
5. The method of claim 1 , wherein the quaternary ammonium base comprises at least one compound selected from the group consisting of tetramethyl ammonium hydroxide, tetraethyl ammonium hydroxide, tetrapropyl ammonium hydroxide, tetrabutyl ammonium hydroxide.