Beam blanker and method for blanking a charged particle beam
US10410820B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 2017 |
| Grant date | Sep 10, 2019 |
| Priority date | — |
| Expiry date | Nov 28, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31742
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a beam blanker for a scanning particle microscope for blanking a charged particle beam having a beam axis, along which charged particles propagate before entering the beam blanker, wherein the beam blanker comprises: (a) at least one stop having an aperture, through which the charged particle beam can pass; (b) at least one first and one second deflection element, which are each configured to deflect the particle beam from the beam axis in a first and a second direction, respectively, upon a voltage being present; and (c) a deflection controller configured to apply a first AC voltage having a first frequency to the first deflection element and a second AC voltage having a second frequency to the second deflection element, wherein the deflection controller sets a difference frequency between the first and second AC voltages such that pulses of the charged particle beam have a predefined pulse period and during the pulse period outside the pulse duration substantially no charged particles pass through the aperture of the stop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.