Thin resist with nitride hard mask for via etch application
US6127070A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 1, 1998 |
| Grant date | Oct 3, 2000 |
| Priority date | — |
| Expiry date | Dec 1, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a via structure is provided. In the method, a dielectric layer is formed on an anti-reflective coating (ARC) layer covering a first metal layer; and a nitride layer is formed on the dielectric layer. An ultra-thin photoresist layer is formed on the nitride layer, and the ultra-thin photoresist layer is patterned with short wavelength radiation to define a pattern for a via. The patterned ultra-thin photoresist layer is used as a mask during a first etch step to transfer the via pattern to the nitride layer. The first etch step includes an etch chemistry that is selective to the nitride layer over the ultra-thin photoresist layer and the dielectric layer. The nitride layer is employed as a hard mask during a second etch step to form a contact hole corresponding to the via pattern by etching portions of the dielectric layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.