Wire bonding process for copper-metallized integrated circuits
US6800555B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2001 |
| Grant date | Oct 5, 2004 |
| Priority date | — |
| Expiry date | Mar 23, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3025
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A robust, reliable and low-cost metal structure and process enabling electrical wire/ribbon connections to the interconnecting copper metallization of integrated circuits. The structure comprises a layer of barrier metal that resists copper diffusion, deposited on the non-oxidized copper surface in a thickness such that the barrier layer reduces the diffusion of copper at 250° C. by more than 80% compared with the absence of the barrier metal. The structure further comprises an outermost bondable layer which reduces the diffusion of the barrier metal at 250° C. by more than 80% compared with the absence of the bondable metal. Finally, a metal wire is bonded to the outermost layer for metallurgical connection.The barrier metal is selected from a group consisting of nickel, cobalt, chromium, molybdenum, titanium, tungsten, and alloys thereof. The outermost bondable metal layer is selected from a group consisting of gold, platinum, and silver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.