Chemical-mechanical polishing techniques and methods of end point detection in chemical-mechanical polishing processes
US5439551A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1994 |
| Grant date | Aug 8, 1995 |
| Priority date | — |
| Expiry date | Mar 2, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B49/003
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A semiconductor processing method of detecting polishing end point in a chemical-mechanical polishing planarization process includes the following steps: a) chemical-mechanical polishing an outer surface of a semiconductor substrate using a chemical-mechanical polishing pad; b) during such chemical-mechanical polishing, measuring sound waves emanating from the chemical-mechanical polishing action of the substrate against the pad; c) detecting a change in the sound waves as the surface being chemical-mechanical polished becomes substantially planar; and d) ceasing chemical-mechanical polishing upon detection of the change. Alternately instead of ceasing chemical-mechanical polishing, a mechanical polishing process operational parameter could be changed upon detection of the change and then continuing mechanical polishing with the changed operational parameter. In another aspect of the invention, first and second layers to be polished are provided on a semiconductor wafer. The second layer is in situ measured during polishing to determine its substantial complete removal from the substrate by chemical-mechanical polishing. Such in situ measuring of the second layer during polishing m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.