PARTICULATE SLURRIES AND METHODS OF MAKING THE SAME
The present disclosure provides a method of making a chemical mechanical planarization slurry. The method includes contacting a chemical mechanical planarization slurry precursor including a carrier and a plurality of abrasive particles with a semi-permeable fiber membrane. Upon contact, the method further includes separating the chemical mechanical planarization slurry precursor into a concentrate and an effluent. The concentrate includes the chemical mechanical planarization slurry and the effluent includes the carrier and a plurality of particles. The particles of the effluent have a median size that is less than a median size of the abrasive particles of the concentrate. In the method a pressure difference measured between an inlet to which the chemical mechanical planarization slurry precursor is supplied and a first outlet to which the effluent is supplied is in a range of from about 1 psi to about 15 psi.
1 . A method of making a particulate slurry, the method comprising:
contacting a particulate slurry precursor including a carrier and a plurality of abrasive particles with a semi-permeable fiber membrane;
separating the particulate slurry precursor into a concentrate and an effluent, wherein
the concentrate comprises the particulate slurry;
the effluent comprises the carrier and a plurality of particles disposed in the carrier, the particles of the effluent having a median size that is less than a median size of the abrasive particles of the concentrate; and
a pressure difference measured between an inlet to which the particulate slurry precursor is supplied and a first outlet to which the effluent is supplied is in a range of from about 1 psi to about 15 psi.
2 . The method of claim 1 , further comprising recirculating the concentrate at least once.
3 . The method of claim 1 , wherein a majority of the particles of the effluent have a median size that is less than or equal to about 20 nm.
4 . The method of claim 3 , wherein a majority of the particles of the effluent have a median size that is less than or equal to about 10 nm.
5 . The method of claim 1 , wherein the pressure difference between the inlet and the first outlet is in a range of from about 1 psi to about 10 psi.
6 . The method of claim 5 , wherein the pressure difference between the inlet and the first outlet is in a range of from about 2 psi to about 4 psi.
7 . The method of claim 1 , wherein a greater amount of the particulate slurry precursor passes through a second outlet as the concentrate than through a first outlet as the effluent.
8 . The method of claim 1 , wherein the first outlet is free of a restriction.
9 . A system for producing a particulate slurry, the system comprising:
a semi-permeable fiber membrane;
a particulate slurry precursor in contact with the semi-permeable fiber membrane, the particulate precursor slurry including a carrier and a plurality of abrasive particles; and
a case that at least partially contains the semi-permeable fiber membrane, the case comprising:
an inlet feeding into the case;
a first outlet; and
a second outlet,
a recirculation line attached to the second outlet and in fluid communication with the inlet,
wherein the system is configured to create a pressure difference measured between the inlet and the first outlet in a range of from about 1 psi to about 15 psi.
10 . The system of claim 9 , wherein the semi-permeable fiber membrane comprises a hollow fiber.
11 . The system of claim 9 , wherein the semi-permeable fiber membrane comprises:
a hydrophobic aromatic sulfone polymer; and
a hydrophilic polymer.
12 . The system of claim 9 , wherein the semi-permeable fiber membrane comprises an inner surface, an outer surface facing outwards and an intermediate wall having a wall thickness, wherein in the inner surface the fiber membrane has an open-pore separating layer, adjoining a separating layer proximate to the outer surface and adjoining a supporting layer.
13 . The system of claim 12 , wherein pores of the separating layer have an average size in a range of from about 5 μm to about 100 μm.
14 . The system of claim 13 , wherein pores of the separating layer have an average size in a range of from about 10 μm to about 50 μm.
15 . The system of claim 9 , wherein the semi-permeable fiber membrane comprises one or more hollow fibers having an inner diameter in a range of from about 0.5 μm to about 2 mm.
16 . A particulate slurry comprising:
a carrier; and
a plurality of abrasive particles disposed in the carrier, the plurality of abrasive particles having a size distribution curve substantially conforming to a positively skewed distribution curve relative to a normal distribution curve, wherein a majority of the abrasive particles have a median size of at least 20 nm.
17 . The particulate slurry of claim 16 , wherein a majority of the abrasive particles have a median size in a range of from about 20 nm to about 100 nm.
18 . The particulate slurry of claim 16 , wherein the abrasive particles individually comprise a substantially spherical morphology.
19 . The particulate slurry of claim 16 , wherein the abrasive particles comprise an inorganic material, an organic material, or a mixture thereof.
20 . The particulate slurry of claim 19 , wherein the inorganic material comprises alumina, silica, ceria, a silicon nitride, a glass, an alumina-phosphorous pentoxide, an alumina-boria-silica, a zirconia, a zirconia-alumina, a zirconia-silica, an aluminum oxide, a heat-treated aluminum oxide, a sintered aluminum oxide, a silicon carbide material, titanium diboride, boron carbide, tungsten carbide, titanium carbide, diamond, cubic boron nitride, garnet, fused alumina-zirconia, cerium oxide, zirconium oxide, titanium oxide, or a combination thereof.