Electron beam lithography focusing through spherical aberration introduction
US6440620B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 2000 |
| Grant date | Aug 27, 2002 |
| Priority date | — |
| Expiry date | Nov 13, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/143
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
An apparatus and method of focusing including a source for producing an electron beam, a mask and a projection column, through which the electron beam passes, and a wafer on which the electron beam is to be focused. The wafer is located in a plane where spherical aberrations of the projection column reduce the negative defocusing effect caused by chromatic aberrations in the projection column. The apparatus and method are applicable to general electron patterning tools, electron patterning tools where a thickness of the mask is smaller than an electron mean free path of the electron patterning tool, and the SCALPEL™ electron patterning tool.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.