Method for making guiding lines with oxidized sidewalls for use in directed self-assembly (DSA) of block copolymers
US9431219B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2015 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | May 5, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31138
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method that uses both electron beam (e-beam) lithography and directed self-assembly (DSA) of block copolymers (BCPs) makes guiding lines with oxidized sidewalls for use in subsequent DSA of BCPs. A series of films is deposited on a substrate including a first cross-linked polymer mat layer, a layer of resist, an etch stop layer resistant to oxygen reactive-ion-etching, a second cross-linked polymer mat layer, and an e-beam resist. After patterning and etching the second mat layer, a BCP self-assembles onto the patterned second mat layer and one of the BCP components is removed. Then the second mat layer is etched, using the remaining BCP component as an etch mask. Additional etching steps then create guiding lines of the first mat layer with oxidized sidewalls. The resulting guiding lines have better quality and lower roughness than guiding lines made with just e-beam lithography.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.