Charged particle beam apparatus, multi-beamlet assembly, and method of inspecting a specimen

US11495433B1 · kind B1 · utility

Assignee

• ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH · DE

Inventors

• Benjamin John Cook · Munich, DE
• Dieter Winkler · Munich, DE
• Markus Thomann · Poing, DE
• Thomas Kemen · Meppen, DE
• Roman Barday · Poing, DE

Key dates

• Filing date: Apr 15, 2021
• Grant date: Nov 8, 2022
• Expiry date: Apr 15, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J2237/2817
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A charged particle beam apparatus for inspecting a specimen with a plurality of beamlets is described. The charged particle beam apparatus includes a charged particle beam emitter (105) for generating a charged particle beam (11) propagating along an optical axis (A) and a multi-beamlet generation- and correction-assembly (120), including a first multi-aperture electrode (121) with a first plurality of apertures for creating the plurality of beamlets from the charged particle beam, at least one second multi-aperture electrode (122) with a second plurality of apertures of varying diameters for the plurality of beamlets for providing a field curvature correction, and a plurality of multipoles (123) for individually influencing each of the plurality of beamlets, wherein the multi-beamlet generation- and correction-assembly (120) is configured to focus the plurality of beamlets to provide a plurality of intermediate beamlet crossovers. The charged particle beam apparatus further includes an objective lens (150) for focusing each of the plurality of beamlets to a separate location on the specimen, and a single transfer lens (130) for beamlet collimation arranged between the multi-beamle…