Method and apparatus for detecting presence of residual polishing slurry subsequent to polishing of a semiconductor wafer
US6375791B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1999 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Dec 20, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B49/12
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of detecting presence of a polishing slurry on a semiconductor wafer subsequent to polishing of the wafer includes the step of adding a chemical marker to the polishing slurry. The method also includes the step of polishing a first side of the wafer in order to remove material from the wafer. In addition, the method includes the step of applying the polishing slurry to the first side of the wafer during the polishing step. Moreover, the method includes the step of ceasing the polishing step when the wafer has been polished to a predetermined level. Yet further, the method includes the step of directing incident electromagnetic radiation onto the wafer subsequent to the ceasing step. The method also includes the step of detecting a physical characteristic of resultant electromagnetic radiation which is produced in response to the incident electromagnetic radiation being directed onto the wafer. Moreover, the method includes the step of determining presence of the chemical marker so as to determine presence of the polishing slurry on the wafer based on the physical characteristic of the resultant electromagnetic radiation. A polishing system for polishing a semiconductor waf…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.