Exposure dose control of rotating electron beam recorder
US7218470B2 · kind B2 · utility
6Cited by
4References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 2, 2003 |
| Grant date | May 15, 2007 |
| Priority date | — |
| Expiry date | Feb 17, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59633
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a beam lithography operation the relative motion between a work piece and the exposure beam produces variations in linear speed at different regions of the work piece surface. For example, if a disk work piece rotates with a constant angular velocity (CAV) relative to the beam, the linear surface speed relative to the beam impact point increases in proportion to increasing radial distance of that point from the center of the disk. To provide uniform exposure dose, the duty cycle of pulses of the exposure beam are varied in accord with radial distance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.