Optics for generation of high current density patterned charged particle beams
US7786454B2 · kind B2 · utility
Assignees
Inventor
Key dates
| Filing date | Sep 12, 2008 |
| Grant date | Aug 31, 2010 |
| Priority date | — |
| Expiry date | Mar 4, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/1534
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A direct-write electron beam lithography system employing a patterned beam-defining aperture to enable the generation of high current-density shaped beams without the need for multiple beam-shaping apertures, lenses and deflectors is disclosed. Beam blanking is accomplished without the need for an intermediate crossover between the electron source and the wafer being patterned by means of a double-deflection blanker, which also facilitates proximity effect correction. A simple type of “moving lens” is utilized to eliminate off-axis aberrations in the shaped beam. A method for designing the patterned beam-defining aperture is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.