Driving a carrier head in a wafer polishing system
US6506099B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 2000 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Apr 5, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B47/10
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A wafer polishing apparatus includes a carrier head 50 having a central axis 70 and a drive shaft 52 coupled to the carrier head. A first input pulley 86 or input gear 86A is coupled to the drive shaft to drive the carrier head about its central axis. A second input pulley 72 or input gear 72A is coupled to the carrier head to drive the carrier head in a circular path about a point that is offset from the central axis of the carrier head. A controller 84, can regulate speeds of the input pulleys or input gears while the wafer 10 is held in contact with a polishing pad 30. Rotation of the carrier head about a point that is offset from the axis of the carrier head can sweep the carrier head across the larger area of the polishing pad. The sweeping motion of the carrier head across the pad can help randomize non-uniformities in the pad and can reduce the amount of wear to the pad as the wafer is moved across it.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.