Method of chemical mechanical polishing of alumina
US9878420B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 2, 2016 |
| Grant date | Jan 30, 2018 |
| Priority date | — |
| Expiry date | Nov 2, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F3/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A CMP method uses a slurry including colloidal metal oxide or colloidal semiconductor oxide particles (colloidal particles) in water. At least one particle feature is selected from (i) the colloidal particles having a polydispersity >30%, and (ii) mixed particle types including the colloidal particles having an average primary size >50 nm mixed with fumed oxide particles having average primary size <25 nm. A substrate having an alumina surface is placed into a CMP apparatus, and CMP is performed with a rotating polishing pad and the slurry to polish the alumina surface. The polydispersity is determined by a polydispersity formula for a distribution width (w) involving width w1 and width w2 at a second larger particle size. The polydispersity formula=(w2−w1)×100/dav which includes 63% of a total of the colloidal particles by volume and day is an average particle size of the colloidal particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.