Reactive ion etching assisted lift-off processes for fabricating thick metallization patterns with tight pitch
US10714341B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 2017 |
| Grant date | Jul 14, 2020 |
| Priority date | — |
| Expiry date | Jun 16, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L23/528
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Lift-off methods for fabricating metal line patterns on a substrate are provided. For example, a method to fabricate a device includes forming a sacrificial layer on a substrate and forming a photoresist mask over the sacrificial layer, isotropically etching a portion of the sacrificial layer exposed through an opening of the photoresist mask to form an undercut region in the sacrificial layer below the photoresist mask, wherein the undercut region defines an overhang structure, and anisotropically etching a portion of the sacrificial layer exposed through the opening of the photoresist mask to form an opening through the sacrificial layer down to the substrate. Metallic material is deposited to cover the photoresist mask and to at least partially fill the opening formed in the sacrificial layer without coating the overhang structure with metallic material. The sacrificial layer is dissolved to lift-off the metallic material covering the photoresist mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.