System and method for fabricating contact holes
US7384725B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2004 |
| Grant date | Jun 10, 2008 |
| Priority date | — |
| Expiry date | Oct 29, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70158
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of forming a plurality of contact holes of varying pitch and density in a contact layer of an integrated circuit device is provided. The plurality of contact holes can include a plurality of regularly spaced contact holes having a first pitch along a first direction and a plurality of semi-isolated contact holes having a second pitch along a second direction. A double-dipole illumination source can transmit light energy through a mask having a pattern corresponding to a desired contact hole pattern. The double-dipole illumination source can include a first dipole aperture, which is oriented and optimized for patterning the regularly spaced contact holes, and a second dipole aperture, which is oriented substantially orthogonal to the first dipole aperture and optimized for patterning the plurality of semi-isolated contact holes. The contact layer can be etched using the patterned photoresist layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.