Methods of and apparatus for controlling polishing surface characteristics for chemical mechanical polishing
US7040954B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2004 |
| Grant date | May 9, 2006 |
| Priority date | — |
| Expiry date | Sep 28, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B49/18
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Apparatus and methods control CMP to uniformly polish a series of wafers. Average motor current I(avg) drawn by, and related average work W(avg) performed by, motors during CMP on the wafers reliably indicate quality of a roughness polishing characteristic of a polishing surface of a polishing pad. A conditioner controller controls a rate at which the quality of the polishing surface is restored by conditioning in relation to a rate of change of the quality of the polishing surface due to the CMP. Motor current is measured and averaged over many CMP-processed wafers. The method defines a baseline range of values of average work and controls conditioning according to whether average work is within the baseline range. When the polishing surface moves at constant velocity relative to each of the wafers that are being polished, a control signal based on average motor current represents the quality of the polishing characteristic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.