Method for forming copper wiring in a semiconductor device
US8252686B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 2009 |
| Grant date | Aug 28, 2012 |
| Priority date | — |
| Expiry date | Feb 25, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76883
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for forming a copper wiring and the prevention of copper ion migration in a semiconductor device is disclosed herein. The process includes conducting a post-cleaning process for a copper layer that is to form the cooper wiring after already having undergone a CMP process. The post-cleaning process includes conducting a primary chemical cleaning using a citric acid-based chemical. A secondary chemical cleaning is then conducted on the copper layer having undergone the primary chemical cleaning using an ascorbic acid-based chemical. After the post-cleaning process is completed, the migration of copper ions over time is prevented thereby improving the reliability of the semiconductor device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.