Process of planarizing a wafer with a large step height and/or surface area features
US8580690B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2011 |
| Grant date | Nov 12, 2013 |
| Priority date | — |
| Expiry date | Oct 22, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/09
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A blanket stop layer is conformally formed on a layer with a large step height. A first chemical mechanical polishing process is performed to remove the blanket stop layer atop the layer in the raised region. A second chemical mechanical polishing process is performed to planarize the wafer using the blanket stop layer as a stop layer when the layer is lower than or at a same level as the blanket stop layer or using the layer as a stop layer when the blanket stop layer is lower than or at a same level as the layer, or a selective dry etch is performed to remove the layer in the raised region. Thus, the layer in the raised region can be easily removed without occurrence of dishing in the non-raised region which is protected by the blanket stop layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.