Method of etching dielectric layers using a removable hardmask
US6458516B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2000 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Apr 18, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32136
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of patterning a layer of dielectric material having a thickness greater than 1,000 å, and typically a thickness greater than 5,000 å. The method is particularly useful for forming a high aspect ratio via or a high aspect ratio contact including self-aligned contact structures, where the aspect ratio is typically greater than 3 and the feature size of the contact is about 0.25 &mgr;m or less. In particular, an organic, polymeric-based masking material is used in a plasma etch process for transferring a desired pattern through an underlying layer of dielectric material. The combination of masking material and plasma source gas must provide the necessary high selectivity toward etching of the underlying layer of dielectric material. The selectivity is preferably greater than 3:1, where the etch rate of the dielectric material is at least 3 times greater than the etch rate of the organic, polymeric-based masking material. The dielectric material may be inorganic, for example, silicon oxide; doped silicon oxide; carbon-containing silicon oxide; SOG; BPSG; and similar materials. The dielectric material may be also be organic, where a high temperature organic-based ma…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.