Electromigration resistant aluminum-based metal interconnect structure
US8003536B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 2, 2009 |
| Grant date | Aug 23, 2011 |
| Priority date | — |
| Expiry date | Jan 13, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2221/1078
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A vertical metallic stack, from bottom to top, of an elemental metal liner, a metal nitride liner, a Ti liner, an aluminum portion, and a metal nitride cap, is formed on an underlying metal interconnect structure. The vertical metallic stack is annealed at an elevated temperature to induce formation of a TiAl3 liner by reaction of the Ti liner with the material of the aluminum portion. The material of the TiAl3 liner is resistant to electromigration, thereby providing enhanced electromigration resistance to the vertical metallic stack comprising the elemental metal liner, the metal nitride liner, the TiAl3 liner, the aluminum portion, and the metal nitride cap. The effect of enhanced electromigration resistance may be more prominent in areas in which the metal nitride cap suffers from erosion during processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.