CHARGED PARTICLE OPTICAL SYSTEM COMPRISING AN ELECTROSTATIC DEFLECTOR

摘要

A charged particle optical system comprising an electrostatic deflector for the deflection of a plurality of beamlets of charged particles which electrostatic deflector comprises a first and a second electrode which are at least partially freestanding, said deflector deflecting the said plurality of beamlets by operation of an electric field between the electrodes between which the said plurality of beamlets passes, the said plurality of beamlets defining a passing window, said passing window extending in a first direction, wherein said plurality of beamlets is arranged in a single row extending in said first direction and a dimension of said passing window in a direction transverse to said first direction matching a diameter of said beamlets and wherein a substantial part of the electrostatic deflector extends beyond the passing window in said first direction.