Post fuse slag etch
US6316350A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2000 |
| Grant date | Nov 13, 2001 |
| Priority date | — |
| Expiry date | Oct 26, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A post laser blown fuse slag etch for a copper fuse (30) with a barrier metal liner (18), (e.g., Ta.sub.x N.sub.y, Ta, Ti, Ti.sub.x N.sub.y). After the fuse (30) is blown, copper and copper complexes may be selectively removed using a nitric acid and H.sub.2 O.sub.2 solution. Then, a corrosion inhibitor is used to passivate the surface of exposed copper (34). Next, the barrier metal (18) of slag (22) is removed using a strong basic etch chemistry comprising a base plus H.sub.2 O.sub.2. This solution removes the barrier metal selectively with respect to passivation layer (e.g., silicon nitride) (16) and oxides/FSG (12). A diluted HF solution may then be used to remove any trace metal or oxidized copper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.