Low selectivity chemical mechanical polishing (CMP) process for use on integrated circuit metal interconnects
US6045435A · kind A · utility
22Cited by
10References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1997 |
| Grant date | Apr 4, 2000 |
| Priority date | — |
| Expiry date | Aug 4, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/7684
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for polishing a metal layer (20) containing a combination of wide features (12), low density features (14), and high density features (18), is illustrated. A hydrophilic polish pad (24) having a shore D hardness of greater than 50 is used along with slurry (22) containing silica and an acidic based oxidizer such as oxadic acid in a chemical mechanical polishing (CMP) process. The result is less than 5:1 and preferably 1:1. This low selectivity results in the metal layer (20) being polished to a level below the surface of the surrounding oxide in a timed-controlled polish.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.