In a charged-particle lithography apparatus, during writing a desired pattern, the duration of exposure slots is adapted to compensate for fluctuations of the particle beam. In the writing process the aperture images are mutually overlapping on the target so each pixel is exposed through a number of aperture images overlapping at the respective pixel, which results in an exposure of the respective pixel through an effective pixel exposure time, i.e., the sum of durations of contributing exposure slots, and the exposure slot durations are adjusted by: (i) determining a desired duration of the effective pixel exposure time for the pixels, as a function of the time of exposure of the pixels, (ii) determining contributing exposure slots for the pixels, (iii) calculating durations for the contributing exposure slots thus determined such that the sum of the durations over said contributing exposure slots is an actual effective exposure time which approximates said desired duration of the effective pixel exposure time. The durations in step (iii) are calculated in accordance with a predetermined set of allowed durations, wherein at least one of the durations thus calculated is different from the other durations selected for said set of exposure slots.

In one embodiment, a writing data generation method is for generating writing data used by a multi-charged particle beam writing apparatus. The writing data generation method includes referring to library data in which a vertex sequence including a plurality of vertices is registered, and extracting a portion of an outer line of a figure contained in design data, the portion corresponding to the vertex sequence, and representing the extracted portion by information which identifies the vertex sequence and information which indicates a connection method for the plurality of vertices of the vertex sequence, and generating the writing data.

The purpose of the present invention is to provide a charged particle beam device with which it is possible to identify, to a high degree of accuracy, repeat patterns generated by a multiple exposure method such as SADP or SAQP. In order to achieve this purpose, there is proposed a charged particle beam device for: irradiating a first position on a sample with a charged particle beam to form an irradiation mark on the sample; after the formation of the irradiation mark, scanning the charged particle beam on a first visual field which includes the first position and which is larger than the irradiation mark, and thereby acquiring a first image; scanning the charged particle beam on a second visual field which includes the first position, which is larger than the irradiation mark, and which is in a different position from the first visual field, thereby acquiring a second image; and synthesizing the first image and the second image so as to overlap the irradiation marks included in the first image and the second image.

A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.

A method of pattern data preparation includes the following steps. A desired pattern to be formed on a surface of a layer is inputted. A first set of beam shots are determined, and a first calculated pattern on the surface is calculated from the first set of beam shots. The first calculated pattern is rotated, so that a boundary of the desired pattern corresponding to a non-smooth boundary of the first calculated pattern is parallel to a boundary constituted by beam shots. A second set of beam shots are determined to revise the non-smooth boundary of the first calculated pattern, thereby calculating a second calculated pattern being close to the desired pattern on the surface. The present invention also provides a method of forming a pattern in a layer.

A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.

In a charged-particle lithography apparatus, during writing a desired pattern, the duration of exposure slots is adapted to compensate for fluctuations of the particle beam. In the writing process the aperture images are mutually overlapping on the target so each pixel is exposed through a number of aperture images overlapping at the respective pixel, which results in an exposure of the respective pixel through an effective pixel exposure time, i.e., the sum of durations of contributing exposure slots, and the exposure slot durations are adjusted by: (i) determining a desired duration of the effective pixel exposure time for the pixels, as a function of the time of exposure of the pixels, (ii) determining contributing exposure slots for the pixels, (iii) calculating durations for the contributing exposure slots thus determined such that the sum of the durations over said contributing exposure slots is an actual effective exposure time which approximates said desired duration of the effective pixel exposure time.

The durations in step (iii) are calculated in accordance with a predetermined set of allowed durations, wherein at least one of the durations thus calculated is different from the other durations selected for said set of exposure slots

The present disclosure provides one embodiment of an IC method. First pattern densities (PDs) of a plurality of templates of an IC design layout are received. Then a high PD outlier template and a low PD outlier template from the plurality of templates are identified. The high PD outlier template is split into multiple subsets of template and each subset of template carries a portion of PD of the high PD outlier template. A PD uniformity (PDU) optimization is performed to the low PD outlier template and multiple individual exposure processes are applied by using respective subset of templates.

A charged particle beam lithography apparatus, includes a plurality of multiple-beam sets, each of which including a plurality of irradiation sources each generating an independent charged particle beam, a plurality of objective deflectors, each arranged for a corresponding charged particle beam, and configured to deflect the corresponding charged particle beam to a desired position on a substrate, and a plurality of electrostatic or electromagnetic lens fields each to focus the corresponding charged particle beam on the target object; a plurality of common deflection amplifiers, arranged for each multiple-beam set, and each of the plurality of common deflection amplifiers being configured to commonly control the plurality of objective deflectors arranged in a same multiple-beam set; a plurality of individual ON/OFF mechanisms configured to individually turn ON/OFF a beam irradiated from each irradiation source; and one or more multiple-beam clusters including the plurality of multiple-beam sets.

A writing data generating method for generating writing data used in a multi charged particle beam writing apparatus, that can suppress a data amount and a calculation amount in a multi charged particle beam writing apparatus generated from design data including a figure having a curve. The method includes calculating a pair of curves each representing a curve portion of a figure included in design data, the curves each being defined by a plurality of control points, and generating the writing data by expressing a position of a second control point adjacent in a traveling direction of the curve to a first control point of the plurality of control points as a displacement from the first control point in the traveling direction of the curve and a displacement from the first control point in a direction orthogonal to the traveling direction.