Patent ID: 6956211
Filing Date: 2005-10-18
Classification: H01J

Abstract:
1. A charged particle beam apparatus comprising a charged particle source and a charged particle optical system for focusing a beam of charged particles emitted by said charged particle source and scanning a sample with the focused beam, said apparatus further comprising: at least first and second deflectors for controlling the incident position of the charged particle beam on at least two focusing lenses including an objective lens, wherein the incident position of the charged particle beam on said objective lens is controlled by said first deflector in order to irradiate said sample with said charged particle beam from a direction that is inclined with respect to the optical axis of said objective lens, and wherein the incident position of the charged particle beam on at least one of said focusing lenses other than said objective lens is controlled by said second deflector such that an off-axis chromatic aberration is produced that cancels an off-axis chromatic aberration produced by the objective lens when the incident position of said charged particle beam on said objective lens is controlled.