Use of boron carbide as an etch-stop and barrier layer for copper dual damascene metallization
US6424044B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Jan 18, 2002 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Jan 18, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a boron carbide layer for use as a barrier and an etch-stop layer in a copper dual damascene structure, and the structure itself are disclosed. In addition to providing a good barrier to copper diffusion, good insulating properties, high etch selectivity with respect to dielectric insulators, boron carbide also provides good electrical characteristics because of its low dielectric constant of less than 5. The amorphous boron carbide is formed in a PECVD chamber by introducing a boron source gas such as B2H6, B5H9+, and carbon source gas such as CH4 and C2H6 at a deposition temperature of about 400° C. Any one, or any combination of the passivation, etch-stop, cap layers of the damascene structure can comprise boron carbide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.