In one embodiment, a multi charged particle beam evaluation method includes writing a plurality of evaluation patterns on a substrate by using multi charged particle beams, with a design value of a line width changed by a predetermined change amount at a predetermined pitch, measuring the line widths of the plurality of evaluation patterns thus written, and extracting a variation in a specific period of a distribution of differences between results of a measurement value and the design value of each of the line widths of the plurality of evaluation patterns. The predetermined change amount is equal to or larger than data resolution and smaller than a size of each of pixels, each of which is a unit region to be irradiated with one of the multi charged particle beams.

According to one aspect of the present invention, an electron beam irradiation apparatus includes a photoelectric surface configured to receive irradiation of excitation light on a side of a front surface, and generate electron beams from a side of a back surface; a blanking aperture array mechanism provided with passage holes corresponding to the electron beams and configured to perform deflection control on each of the plurality of electron beams passing through the passage holes; and an adjustment mechanism configured to adjust at least one of an orbit of transmitted light that passes through at least one of arrangement objects including the photoelectric surface, the blanking aperture array mechanism, and the limit aperture substrate up to the stage and reaches the stage, among an irradiated excitation light, and an orbit of the electron beams, wherein the arrangement objects shield at least a part of the transmitted light.

A blanking deflector according to an embodiment includes: a first electrode comprising a first insulator, a first material film coating all surfaces of the first insulator and having lower resistance than the first insulator, and a first low-resistance film coating part or all of surfaces of the first material film and having lower resistance than the first material film; and a second electrode comprising a second insulator, a second material film coating all surfaces of the second insulator and having lower resistance than the second insulator, and a second low-resistance film coating part or all of surfaces of the second material film and having lower resistance than the second material film, wherein the blanking deflector controls whether to irradiate a specimen with a charged particle beam by causing the charged particle beam to pass between the first electrode and the second electrode.

A charged particle beam system is disclosed, comprising: a charged particle beam generator for generating a beam of charged particles; a charged particle optical column arranged in a vacuum chamber, wherein the charged particle optical column is arranged for projecting the beam of charged particles onto a target, and wherein the charged particle optical column comprises a charged particle optical element for influencing the beam of charged particles; a source for providing a cleaning agent; a conduit connected to the source and arranged for introducing the cleaning agent towards the charged particle optical element; wherein the charged particle optical element comprises: a charged particle transmitting aperture for transmitting and/or influencing the beam of charged particles, and at least one vent hole for providing a flow path between a first side and a second side of the charged particle optical element, wherein the vent hole has a cross section which is larger than a cross section of the charged particle transmitting aperture. Further, a method for preventing or removing contamination in the charged particle transmitting apertures is disclosed, comprising the step of introducing the cleaning agent while the beam generator is active.

A method for controlling operation of an electron emission source includes acquiring, while varying an emission current of an electron beam, a characteristic between a surface current of a target object at a position on the surface of the target object irradiated with the electron beam, and the emission current, calculating, based on the characteristic, first gradient values each obtained by dividing the surface current of the target object by the emission current, in a predetermined range of the emission current in the characteristic, calculating a second gradient value by dividing a surface current of the target object by an emission current in a state where the electron beam has been adjusted, and adjusting a cathode temperature to make the second gradient value in the state where the electron beam has been adjusted be in the range of the first gradient values in the predetermined range of the emission current.

A multi-electron beam writing apparatus includes a light source array to include plural light sources and generate plural first lights, a multi-lens array to include plural first lenses, and to divide the plural first lights into plural second lights by that each of the plural first lights illuminates a corresponding lens set of plural lens sets each composed of plural second lenses being a portion of the plural first lenses and by that each of lenses, being at least a part of the plural second lenses, is irradiated with two or more first lights of the plural first lights, a photoemissive surface to receive the plural second lights through its upper surface, and emit multiple photoelectron beams from its back surface, and a blanking aperture array mechanism to perform an individual blanking control by individually switching between ON and OFF of each of the multiple photoelectron beams.

Lithographic apparatuses suitable for complementary e-beam lithography (CEBL) are described. In an example, a method of forming a pattern for a semiconductor structure includes forming a pattern of parallel lines above a substrate. The method also includes aligning the substrate in an e-beam tool to provide the pattern of parallel lines parallel with a scan direction of the e-beam tool. The e-beam tool includes a column having a blanker aperture array (BAA) with a staggered pair of columns of openings along an array direction orthogonal to the scan direction. The method also includes forming a pattern of cuts or vias in or above the pattern of parallel lines to provide line breaks for the pattern of parallel lines by scanning the substrate along the scan direction. A cumulative current through the column has a non-zero and substantially uniform cumulative current value throughout the scanning.

A multi-beam apparatus for observing a sample with oblique illumination is proposed. In the apparatus, a new source-conversion unit changes a single electron source into a slant virtual multi-source array, a primary projection imaging system projects the array to form plural probe spots on the sample with oblique illumination, and a condenser lens adjusts the currents of the plural probe spots. In the source-conversion unit, the image-forming means not only forms the slant virtual multi-source array, but also compensates the off-axis aberrations of the plurality of probe spots. The apparatus can provide dark-field images and/or bright-field images of the sample.

Provided is a multi charged particle beam writing apparatus including: an emission unit emitting a charged particle beam; a restriction aperture unit having a first opening having a variable opening area, the restriction aperture unit shielding a portion of the charged particle beam; a shaping aperture array substrate having a plurality of second openings, the shaping aperture array substrate forming multiple beams by allowing the shaping aperture array substrate to be irradiated with the charged particle beam passing through the first opening and allowing a portion of the charged particle beam to pass through the plurality of second openings; and a blanking aperture array substrate having a plurality of third openings, each beam of the multiple beams passing through the plurality of third openings, the blanking aperture array substrate being capable of independently deflecting each beam of the multiple beams.

Systems and methods of measuring beam current in a multi-beam apparatus are disclosed. The multi-beam apparatus may include a charged-particle source configured to generate a primary charged-particle beam, and an aperture array. The aperture array may comprise a plurality of apertures configured to form a plurality of beamlets from the primary charged-particle beam, and a detector including circuitry to detect a current of at least a portion of the primary charged-particle beam irradiating the aperture array. The method of measuring beam current may include irradiating the primary charged-particle beam on the aperture array and detecting an electric current of at least a portion of the primary charged-particle beam.