### Effect of mixing ratio of non-spherical particles in colloidal silica slurry on oxide CMPEffect of mixing ratio of non-spherical particles in colloidal silica slurry on oxide CMP

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 Author Lee, Hojun ♦ Lee, Dasol ♦ Kim, Moonsung ♦ Jeong, Haedo Source SpringerLink Content type Text Publisher Korean Society for Precision Engineering File Format PDF Copyright Year ©2017 Language English
 Subject Domain (in DDC) Technology ♦ Engineering & allied operations Subject Keyword CMP ♦ Mixed abrasive slurry ♦ Mixing ratio ♦ Non-spherical colloidal silica ♦ Oxide ♦ Material removal rate ♦ Industrial and Production Engineering ♦ Materials Science Abstract Colloidal silica and fumed silica are common slurry materials for oxide chemical mechanical polishing (CMP). Non-spherical colloidal silica particles are manufactured via a multi-step feeding method to compensate for the material removal rate of colloidal silica slurry, which is lower than that of fumed silica slurry. Additionally, mixed abrasive slurry has been used by combining non-spherical and spherical colloidal silica particles. Experiments were conducted on a 4-inch wafer with silicon dioxide film (SiO $_{ 2 }$, 1-μm thick) and KOH-based colloidal silica slurry. The slurry had spherical colloidal silica particles with the size of 30 nm and 70 nm and non-spherical colloidal silica particles with the size of 70 nm. Effects of different colloidal particles in the oxide CMP were observed under the same pH condition in order to achieve high material removal rate. The mixing ratios were 2:1, 1:1, and 1:2 respectively. The analysis of the particle combinations showed that the mixing of particles with different sizes caused agglomeration and increased the material removal rate. The relatively smaller spherical particles improved the surface roughness and overall performance, especially when mixed with non-spherical particles. Such mixtures of particles with different sizes and shapes mixed at an appropriate ratio can outperform the fumed silica slurry. ISSN 22347593 Age Range 18 to 22 years ♦ above 22 year Educational Use Research Education Level UG and PG Learning Resource Type Article Publisher Date 2017-10-08 Publisher Place Seoul e-ISSN 20054602 Journal International Journal of Precision Engineering and Manufacturing Volume Number 18 Issue Number 10 Page Count 6 Starting Page 1333 Ending Page 1338