Variable-ratio double-deflection beam blanker
US7928404B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 13, 2008 |
| Grant date | Apr 19, 2011 |
| Priority date | — |
| Expiry date | Sep 11, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/244
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention provides methods for conjugate blanking of a charged particle beam within a charged particle column using a beam blanker. The beam blanker comprises a first deflector, a second deflector and a blanking aperture, the first deflector being positioned between a gun lens and a main lens, the second deflector being positioned between the first deflector and the main lens, the blanking aperture being positioned between the second deflector and the main lens, and the first deflector, the second deflector and the blanking aperture being aligned on the optical axis of the column. A method according to the invention comprises the steps of: configuring electron optical elements of said charged particle column to form a beam in the column either with or without a crossover; configuring the main lens to focus the beam formed by the gun lens onto a substrate plane; deflecting the beam with a first deflector in a first direction; and deflecting the beam with a second deflector in a second direction onto the blanking aperture, wherein the first direction is parallel or anti-parallel to the second direction; and wherein the image at the substrate plane does not move during blanking.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.