Lithographic systems and methods with extended depth of focus
US7876417B2 · kind B2 · utility
26Cited by
28References
8Claims
0Family size
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Key dates
| Filing date | Jul 21, 2006 |
| Grant date | Jan 25, 2011 |
| Priority date | — |
| Expiry date | Oct 14, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70308
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical lithography system that has extended depth of focus exposes a photoresist coating on a wafer, and includes an illumination sub-system, a reticle, and an imaging lens that has a pupil plane function to form an aerial image of the reticle proximate to the photoresist. The pupil plane function provides the extended depth of focus such that the system may be manufactured or used with relaxed tolerance, reduced cost and/or increased throughput. The system may be used to form precise vias within integrated circuits even in the presence of misfocus or misalignment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.