Metal-based etch-stop layer
US11004734B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2019 |
| Grant date | May 11, 2021 |
| Priority date | — |
| Expiry date | Nov 4, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L23/5329
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor structure includes a conductive feature, a first metal-based etch-stop layer over the underlying structure, a metal-free etch-stop layer over the first metal-based etch-stop layer, a second metal-based etch-stop layer over the metal-free etch-stop layer, an interlayer dielectric layer over the second metal-based etch-stop layer, and an interconnect structure extending through the first metal-based etch-stop layer, metal-free etch-stop layer, and the second metal-based etch-stop layer, wherein a bottom portion of the conductive interconnect structure directly contacts the conductive feature. The first metal-based etch-stop layer may include a first metallic component having one of aluminum, tantalum, titanium, or hafnium, and the second metal-based etch-stop layer may include a second metallic component the same as or different from the first metallic component. The first metal-based etch-stop layer and the second metal-based etch-stop layer may both be free of silicon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.