Graded interconnect cap
US10651083B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 2018 |
| Grant date | May 12, 2020 |
| Priority date | — |
| Expiry date | Mar 5, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76883
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A graded cap is formed upon an interconnect, such as a back end of line wire. The graded cap includes a microstructure that uniformly changes from a metal nearest the interconnect to a metal nitride most distal from the interconnect. The graded cap is formed by nitriding a metal cap that is formed upon the interconnect. During nitriding an exposed one or more perimeter portions of the metal cap become a metal nitride with a larger amount or concentration of Nitrogen while one or more inner portions of the metal cap nearest the interconnect may be maintained as the metal or become the metal nitride with a fewer amount or concentration of Nitrogen. The resulting graded cap includes a gradually or uniformly changing microstructure between the one or more inner portions and the one or more perimeter portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.