Electron beam imaging apparatus
US6420714B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 2000 |
| Grant date | Jul 16, 2002 |
| Priority date | — |
| Expiry date | Jun 9, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31791
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus for projection lithography is disclosed. The apparatus has at least one magnetic doublet lens. An aperture scatter filter is interposed between the two lenses of the magnetic doublet lens. The aperture scatter filter is in the back focal plane of the magnetic doublet lens system, or in an equivalent conjugate plane thereof. The apparatus also has two magnetic clamps interposed between the two lenses in the magnetic doublet lens. The clamps are positioned and configured to prevent substantial overlap of the magnetic lens fields. The magnetic clamps are positioned so that the magnetic fields from the lenses in the magnetic doublet lens do not extend to the aperture scatter filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.