Method and apparatus for endpoint detection for chemical mechanical polishing using electrical lapping
US6007405A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1998 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Jul 17, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B49/10
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A chemical mechanical polisher for polishing a surface of a semiconductor wafer is disclosed. The polisher comprises: a polishing table for holding a polishing pad; a rotatable wafer chuck for holding said semiconductor wafer against said polishing pad; an electrical lapping guide secured to said wafer chuck, said electrical lapping guide comprising: a polishable resistive sensor that has a variable resistance dependent upon the amount of material removed from said resistive sensor during polishing; and a bias means for applying a bias to said resistive sensor such that said resistive sensor is in contact with said polishing pad during polishing; a resistance sensing means for determining said variable resistance of said resistive sensor; and a microprocessor for determining the amount of material polished from said resistive sensor based upon said variable resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.