Patent ID: 7470295

Claim:
A polishing slurry comprising: polishing particles comprising: a plurality of grains; a plurality of primary particles formed from agglomeration of one or more of the plurality of grains; and a plurality of secondary particles formed from agglomeration of one or more of the plurality of primary particles, wherein the secondary particles have a median size of 50-450 nm, the primary particles have a median size of 10-300 nm and the grains have a median size of 10-150 nm, and wherein the polishing particles have a particle size distribution including separated first and second polishing particle peaks representing a first group of polishing particles having a first median particle size and a second group of polishing particles having a second median particle size greater than the first median particle size, respectively, a ratio of an area of the first particle peak to an area of the second particle peak is 2.85 to 25.