High speed pattern generator for electron beam lithography
US4698509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1985 |
| Grant date | Oct 6, 1987 |
| Priority date | — |
| Expiry date | Feb 14, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31776
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pattern generator for supplying beam deflection and blanking signals in an electron beam lithography system which writes polygon pattern features by sweeping a beam of rectangular cross-section over each polygon and simultaneously varying the length of the rectangular cross-section. The pattern generator converts polygon size and shape data to an upper shape signal and a lower shape signal. The shaping signals are subtracted to provide a beam length signal. The lower shape signal controls the beam position during writing of the polygon. The pattern generator further includes a ramp generator for sweeping the beam over the polygon. The ramp signal and shaping signals are synchronized by detecting the points in the sweep at which polygon turn points occur. The shape signal generators utilize interleaved operation for high speed. A blanking circuit provides uniform exposure of pattern features by controlling the width of the rectangular beam. The beam is ramped on and off at a rate which matches the rate of the sweep signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.