Method of and system for charged particle beam exposure
US5546319A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1995 |
| Grant date | Aug 13, 1996 |
| Priority date | — |
| Expiry date | Jan 27, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/1504
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
To improve in the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector, a glitch waveform generated during a step change in the output or a D/A converter at the preceding stage of the amplifier, is anticipated and is canceled out with a correction waveform, after the output of the D/A converter has settled, this output is sample held and the step change is interpolated at a smoothing circuit, the deflection area is increased by positioning a electrostatic deflector offset around the optical axis relative to another electrostatic deflector, the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turn, and the alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area. In order to correct the astigmatism of the electromagnetic lens, two stages or coils are provided and an electric current corresponding to the quantity of deflection is supplied to the coils.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.