Multiple step metallization process
US4970176A · kind A · utility
77Cited by
3References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1989 |
| Grant date | Nov 13, 1990 |
| Priority date | — |
| Expiry date | Sep 29, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/025
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Metal step coverage is improved by utilizing a multiple step metallization process. In the first step, a thick portion of a metal layer is deposited on a semiconductor wafer at a cold temperature. The remaining amount of metal is deposited in a second step as the temperature is ramped up to allow for reflow of the metal layer through grain growth, recrystallization and bulk diffusion. The thick portion of the metal layer deposited at the cold temperature is of adequate thickness so that it remains continuous at the higher temperature and enhances via filling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.