Electrode arrangement for electrostatic deflection system

Claim 1

A corpuscular beam processing device comprising subsequently about an optical axis in mutual electron optical alignment an electron gun for producing a corpuscular beam, an aperture adjacent to said electron gun for defining said corpuscular beam cross-section, a first deflection system, a first electron lens, a second deflection system, an electrostatic deflection system, a black-out aperture, at least a second electron lens having a center in said optical axis, a third deflection system, a target plane, a slide being displaceably arranged in said target plane, said first deflection system being for deflecting said corpuscular beam off said optical axis, said first electron lens being for focusing said corpuscular beam into said electrostatic deflection system, said second deflection system being for directing said corpuscular beam into said center of said second electron lens, said second electron lens being arranged adjacent said target plane, said electrostatic deflection system comprising at least two electrode supporting bodies, each of said bodies being provided with a face in opposition to the face of the other electrode body, each face having a leading edge in opposition to said second deflection system, the faces of said bodies having a leading edge distance a o relative to each other and a bottom distance a u relative to each other where a u >a o , each of said bodies having limiting plane faces in opposition to said black-out aperture, said limiting plane faces including obtuse angles with the associated one of said both faces, a plurality of electrodes being provided at least on one of said both faces, said electrodes being of high conductive material compared to the material of said faces, said electrodes being adjacently arranged along the direction of the greatest extension of said one of said both faces, each electrode of said plurality of electrodes on said one of said both faces being provided with an individual supply lead, said one of said both faces being of low electric conductivity compared to the electrode material, each of said plurality of electrodes is of rectangular shape having two sides in parallel and two sides at right angles to the corpuscular beam for substantially each deflected off the optical axis position of said corpuscular beam, said electrostatic deflection system being for deflecting said corpuscular beam off and directing said corpuscular beam to, respectively, said target plane, said black-out aperture being for trapping said corpuscular beam when deflected off the target plane, said third deflection system being for fine positioning said corpuscular beam in said target plane, said second electron lens being for imaging said leading edges into said target plane.