Abstract: A corrector has a strength of a central hexapole field (?HP2) which is selected such that the threefold axial astigmatism (A2) vanishes and the strengths of two equal outer hexapole fields (?HP1,3) are selected such that the overall corrector (5) does not have a sixfold axial astigmatism (A5). The length (L) of the central multipole element (2) in relation to the lengths (L?) of the multipole elements (1 and 3) is chosen such that the axial three-lobed aberration of sixth order (D6) vanishes. A separation between the outer multipole elements (1 and 3) and round lenses (7?, 8?) further spaced apart from a symmetry plane (6) of the corrector corresponds to the focal length (f?) of those round lenses (7?, 8?) plus an additional separation (?z) which is chosen such that the axial three-lobed aberration of fourth order (D4) vanishes for the given lengths L and L?.

Abstract: A corrector (10) for an electron microscope is proposed which is less sensitive to fluctuations of the electrical power supply if a stigmatic intermediate image (9) of the axial fundamental rays (x?, y?) is produced in the quadrupole field (1?) of a first quadrupole element (1) and this quadrupole field (1?) is set such that astigmatic intermediate images (12, 13) of the off-axial fundamental rays (x?, y?) are produced in the region of the center of the quadrupole fields (3?, 4?) of a third (3) and fourth multipole element (4) and there also, due to the setting of the quadrupole field (2?) of a second quadrupole element (2), the axial fundamental rays (x?, y?) of the same section (x, y) as that, in which the intermediate images (12, 13) of the off-axial fundamental rays (x?, y?) are located, each exhibit a maximum.

Abstract: The invention concerns a corrector (9) for chromatic and aperture aberration correction in an electron microscope with six multipoles (1, 2, 3, 4, 5, 6) which are disposed in the optical path (7) one after the other symmetrically with respect to a symmetry plane (8) for generating quadrupole fields (1?, 2?, 3?, 4?, 5?, 6?) and octupole fields, wherein the quadrupole fields (1?, 2?, 3?, 4?, 5?, 6?) of all six multipoles (1, 2, 3, 4, 5, 6) are consecutively rotated through 90° with respect to one another, thereby generating a mirror-symmetrical exchange symmetry of the axial fundamental rays (x?, y?).

Abstract: A corrective for eliminating the third-order aperture aberration and the first-order, first-degree axial chromatic aberration includes two correction pieces, which are arranged one behind the other in the direction of the optical axis, in which each correction piece has a plurality of quadrupole fields (QP) and at least one octupole field (OP.) Each correction piece is constructed such that it is symmetrical with respect to its central plane (S, S?) with each correction piece having an uneven number of at least five quadrupole fields (QP) and at least one octupole field (OP). Each correction piece is further constructed so that it is symmetrical with respect to its central plane. The central quadrupole field is arranged so that it is centered with respect to the central plane of the correction piece and is electromagnetic.

Abstract: According to the invention, the image contrast in electron optics can be improved without causing aberrations that are no longer tolerable by using, for production and correction of the at least one anamorphic image, quadrupole fields before and after this image whose extent in the direction of the optical axis is equal to at least twice their focal length, and wherein at least one of the axial rays, by an appropriate choice of the magnification M of the intermediate image, enters the quadrupole field before the at least one anamorphic image at a slope 1/M such that a length of the anamorphic image is achieved at which any aberrations caused are still within a tolerable range. The invention also relates to devices for implementing this method.

Abstract: The invention concerns a phase plate for electron optical imaging, wherein the zero beam (4) is phase-shifted in order to obtain an image with optimum contrast through interference with the diffracted electron beams (5, 5?). The shading of diffracted electron beams (5, 5?) is kept to a minimum and shading that cannot be reconstructed from the obtained image data is prevented. This is achieved in that the electrode (1?) is designed as a shielded conductor (7), which is disposed to extend from a mounting (8) in a substantially radial direction towards the area of the zero beam (4), wherein the shielded conductor (7) has an end (9) in front of the area of the zero beam (4) such that a field (6) is formed between the conductor (7) and the shielding (10) surrounding it, which overlaps this area. The invention also concerns an imaging method for complete reconstruction of the image and an electron microscope (12) which is provided with the phase plate (1).

Abstract: A corrector (1) for the axial and off-axial beam path of a particle-optical system, comprises a first (10) and a second (20) correction piece, which are disposed one behind the other in the beam path (2) on an optical axis (3).

Abstract: Multipole coils (1, 2, 3, 4, 5, 6) for influencing particle beams have at least two coils (1, 2) which concentrically enclose an imaginary axis (10), wherein a winding (7) made from a flexible circuit board (8) is formed by means of conducting paths (9) disposed thereon for each coil (1, 2, 3, 4, 5, 6) and the circuit boards (8) are rolled into at least one circuit board layer (11, 12, 13, 14). Multipole coils of this kind (1, 2, 3, 4, 5, 6) are utilized for aberration correction in particle optics, wherein the windings (7) of the multipole coils (1, 2, 3, 4, 5, 6) form windows (16) whose width in the peripheral direction is chosen in such a fashion that no secondary interfering fields occur and whose length in the axial direction corresponds at least to its width.

Abstract: The invention concerns a corrector (10) for chromatic and aperture aberration correction in a scanning electron microscope or a scanning transmission electron microscope, comprising four multipole elements (1, 2, 3, 4) which are consecutively disposed in the optical path (9), the first (1) and fourth (4) of which are used to generate quadrupole fields (5, 6) and the second (2) and third (3) of which are used to generate octupole fields (11, 12) and quadrupole fields (7, 7?, 8, 8?), wherein the latter are superposed magnetic (7, 8) and electric (7?, 8?) fields, and wherein the quadrupole fields (5, 6, 7, 8) of all four multipole elements (1, 2, 3, 4) are successively rotated with respect to one another through 90°.

Abstract: A monochromator (1) for a charged particle optics, in particular, for electron microscopy, comprises at least one first deflection element (2, 3) with an electrostatic deflecting field (2?, 3?) for generating a dispersion (4) in the plane (5) of a selection aperture (6) to select charged particles of a desired energy interval (7) and at least one second deflection element (8, 9) with an electrostatic deflecting field (8?, 9?) which eliminates the dispersion (4) of the at least one first deflecting field (2?, 3?). A radiation source (17) comprises such a monochromator (1).

Abstract: A corrector (1) for the axial and off-axial beam path of a particle-optical system, comprises a first (10) and a second (20) correction piece, which are disposed one behind the other in the beam path (2) on an optical axis (3).

Abstract: The invention concerns a corrector (10) for chromatic and aperture aberration correction in a scanning electron microscope or a scanning transmission electron microscope, comprising four multipole elements (1, 2, 3, 4) which are consecutively disposed in the optical path (9), the first (1) and fourth (4) of which are used to generate quadrupole fields (5, 6) and the second (2) and third (3) of which are used to generate octupole fields (11, 12) and quadrupole fields (7, 7?, 8, 8?), wherein the latter are superposed magnetic (7, 8) and electric (7?, 8?) fields, and wherein the quadrupole fields (5, 6, 7, 8) of all four multipole elements (1, 2, 3, 4) are successively rotated with respect to one another through 90°.

Abstract: Multipole coils (1, 2, 3, 4, 5, 6) for influencing particle beams have at least two coils (1, 2) which concentrically enclose an imaginary axis (10), wherein a winding (7) made from a flexible circuit board (8) is formed by means of conducting paths (9) disposed thereon for each coil (1, 2, 3, 4, 5, 6) and the circuit boards (8) are rolled into at least one circuit board layer (11, 12, 13, 14). Multipole coils of this kind (1, 2, 3, 4, 5, 6) are utilized for aberration correction in particle optics, wherein the windings (7) of the multipole coils (1, 2, 3, 4, 5, 6) form windows (16) whose width in the peripheral direction is chosen in such a fashion that no secondary interfering fields occur and whose length in the axial direction corresponds at least to its width.

Abstract: Multipole coils (1, 2, 3, 4, 5, 6) comprise at least two coils (1, 2) which are disposed to concentrically enclose an imaginary axis (10). Multipole coils (1, 2, 3, 4, 5, 6) of this type are designed in such a fashion that effective fields can be generated in the area of an imaginary axis (10) when little installation space is available, and the multipole coils can be reproducibly manufactured with high precision. This is achieved in that, for each coil (1, 2, 3, 4, 5, 6), at least one winding (7) is disposed on a flexible printed circuit board (8) through disposed strip conductors (9), and the printed circuit board (8) is rolled in at least one printed circuit board layer (11, 12, 13, 14).

Abstract: A monochromator (1) for a charged particle optics, in particular, for electron microscopy, comprises at least one first deflection element (2, 3) with an electrostatic deflecting field (2?, 3?) for generating a dispersion (4) in the plane (5) of a selection aperture (6) to select charged particles of a desired energy interval (7) and at least one second deflection element (8, 9) with an electrostatic deflecting field (8?, 9?) which eliminates the dispersion (4) of the at least one first deflecting field (2?, 3?). A radiation source (17) comprises such a monochromator (1).

Abstract: Disclosed is a lens array having a laterally movable axis for corpuscular rays, particularly for transmission from areas of an object surface onto the focal plane by means of electrons. The inventive array consists of a combined lens comprising a cylinder lens and a quadrupole lens provided with slit diaphragms which can be impinged upon by electric and/or magnetic fields. The optical axis of the quadrupole lens is oriented parallel to the axis of the cylinder lens and defines the optical axis of the projection, the position of which can be altered in relation to the axis of the cylinder lens. The quadrupole lens is in focus in the sector in which the cylinder lens is not in focus and is out of focus in the section in which the cylinder lens is in focus. The inventive combined lens can be operated as an immersion lens for projecting secondary electrons. The immersion field consists of at least two adjacent axially aligned fields.

Abstract: An optical particle corrector with a straight optical axis for eliminating color and aperture aberrations in optical particle lenses includes multipole elements in the form of electric and/or magnetic quadrupole and octupole elements. There are at least twelve quadrupole elements and ten octupole elements, in which three quadrupole elements and two octupole elements are assembled into a group. These groups are arranged successively along the straight optical axis, in which a first symmetrical plane is defined between the first and second groups, a second symmetrical plane is defined between the second and third groups and a third symmetrical plane is defined between the third and fourth groups. The multipole elements from one group to another correspond to each other in pairs, in which the multipole elements of the corresponding following group are positioned in reverse order along the straight optical axis in comparison with the corresponding multipole elements of the preceding group.

Abstract: An electrostatic corrector with a rectilinear optical axis has two corrective parts, which are arranged one behind the other along the optical axis and which have respective quadrupole fields and superimposed circular lens fields. The astigmatic intermediate image of one cross-section that is created by an axis point lies in one corrective part and the astigmatic intermediate image of the other cross-section, which is perpendicular to the first cross-section, lies in the other corrective part. An object of the invention is to eliminate the chromatic aberration of particle lenses. To achieve this, an electrostatic corrector is used, which includes two corrector units having similar instrumental construction, with each of the two corrector units having input and output sides on which two additional electrostatic quadrupoles are located. The two corrector units represent the axial paths in a telescopic manner in a 1:1 representation.

Abstract: An electrostatic corrector for eliminating the chromatic aberration of particle lenses, includes a corrector having a straight optical axis and an electrostatic quadrupole for allocating to the objective lens. Two corrector pieces are positioned behind the quadrupole, along the optical axis in the direction of radiation. Each corrector piece has three electrical quadrupole fields with an overlying circular lens field. The quadrupole fields, however, are rotated 90° about the optical axis in relation to each other. This arrangement is adjusted so that the astigmatic first image of one sectional view lies in one corrector piece and the astigmatic first image perpendicular thereto, of the other sectional view, lies in the other corrector piece, with another electrostatic quadrupole being located on the output side.

Abstract: An electron-optical lens arrangement with an axis that can be substantially displaced, and useful for electron lithography, includes a cylinder lens and a quadrupole field. The plane of symmetry of the quadrupole field extends in the mid-plane of the gap pertaining to the cylinder lens. The focussing level of the quadrupole is oriented in the direction of the gap. The amount of the focussing refractive power belonging to the cylinder lens is twice as high as the amount of the quadrupole. A deflection system for the charged particles is connected upstream in the level of the gap pertaining to the cylinder lens and several electrodes or pole shoes, which generate a quadrupole field are provided in the direction of the gap pertaining to the cylinder lens. The electrodes or pole shoes can be individually and, preferably, successively excited and the quadrupole field can be displaced according to the deflection of the particle beam, so that the particle beam impinges upon the area of the quadrupole field.