Advanced manganese/manganese nitride cap/etch mask for air gap formation scheme in nanocopper low-K interconnect
US9349687B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2015 |
| Grant date | May 24, 2016 |
| Priority date | — |
| Expiry date | Dec 19, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
After forming a manganese (Mn)-containing cap layer over interconnects embedded in an interlevel dielectric (ILD) layer, a lithographic stack is formed over the Mn-containing cap layer. The lithographic stack is subsequently patterned to expose a portion of the Mn-containing cap layer that overlies a subset of the interconnects between which the air gaps are to be formed. A portion of the ILD layer located between the subset of the interconnects is damaged through the exposed portion of the Mn-containing cap layer. The damaged portion of the ILD layer is subsequently removed to form openings between the subset of the interconnects. The Mn-containing cap layer acts as a temporary protection layer preventing erosion of the underlying interconnects during the air gap formation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.