Drawing apparatus and drawing method for movable target of multi-column exposure apparatus

Abstract

To provide a method that contributes to reduce the effect of charged particle leakage on patterning accuracy and critical dimensions.SOLUTION: In a charged particle writing method of drawing a pattern on a target using a charged particle multi-beam processing apparatus, a plurality of exposure stripes (51) are drawn along a main direction. The apparatus comprises a plurality of particle-optical columns (411 and 413) arranged across a target surface, the columns forms at least two lines extending in a direction perpendicular to the principal direction. Due to a relative movement between a target and each particle-optical column along the main direction, the column draws exposure each stripe (51) on the target. Each exposure stripe is exposed by either a single particle-optical column or a group of two or more particle-optical columns arranged along the main direction. A row offset is at least two times the width of each stripe. During the drawing of each exposure stripe, the target bypasses an origin of the particle-optical column.SELECTED DRAWING: Figure 4B

Description

[Technical Field]

[0001] This application claims the benefit of Paris Convention priority of European Patent Application No. 24175159.3, filed May 10, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to some improvements in writing patterns using a charged particle multi-beam processing apparatus, in particular for improved positioning of the charged particle beam, where the multi-column charged particle exposure apparatus comprises a movable stage for providing relative motion between a target to be exposed and an array of charged particle columns employing charged particles to write a pattern or respective pattern portions on the target. [Background technology]

[0003] The applicant has realized a charged particle multi-beam device, developed corresponding charged particle optical components, a pattern definition device, and a writing method for the multi-beam, and commercialized a 50 keV electron multi-beam writer called eMET (electron Mask Exposure Tool) or MBMW (multi-beam mask writer) that can be used to realize any photomask for 193 nm immersion lithography, masks for EUV lithography, and templates for nanoimprint lithography. The system invented by the applicant is also called PML2 (Projection Mask-Less Lithography) for the application of an electron beam direct writer (EBDW) to perform writing processes on a substrate. Further details can be found, for example, in the applicant's patents US9,053,906, US9,520,268, US6,768,125, US8,222,621, and US8,378,320.

[0004] Furthermore, the applicant has developed a multi-column exposure apparatus for direct writing applications to 12-inch (12") wafers or 6-inch (6") photomasks in US 7,214,951 and US 9,443,699 B2. An example of a typical multi-column system includes multiple charged particle optical columns, each of which includes an illumination system that delivers a wide, telecentric charged particle beam to a pattern definition system and then to charged particle projection optics. The projection optics include, for example, multiple electrostatic and / or electromagnetic lenses. Furthermore, in US 2023 / 0015805 A1, the applicant has provided a ("slim") lens optimized for multi-column applications that enables a multi-column system with increased current and throughput. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US9,053,906 [Patent Document 2] US9,520,268 [Patent Document 3] US6,768,125 [Patent Document 4] US8,222,621 [Patent Document 5] US$8,378,320 [Patent Document 6] US7,214,951 [Patent Document 7] US9,443,699B2 [Patent Document 8] US2023 / 0015805A1 Summary of the Invention [Problem to be solved by the invention]

[0006] The above patent documents are incorporated herein by reference.

[0007] The inventors have recognized that conventional writing processes using charged particles often suffer from leakage of charged particles to the target during the exposure process. Possible causes of such leakage include non-instantaneous blanking mechanisms, defective blanking of beamlets, or charged particle interference or scattering effects within the optical system. Even when all beamlets are blocked by the pattern definition system, a certain amount of dose will still be dropped onto the target. Particularly when using resists that enable higher resolution but also require a larger dose, it is often necessary to increase the beam current to ensure manageable writing times, i.e., throughput. Increased beam current exacerbates the problem. This leaked additional dose can cause errors in patterning, particularly undesired changes in critical dimensions of pattern components.

[0008] It is therefore an object of the present invention to provide an approach that helps reduce (suppress) the effects of charged particle leakage on patterning accuracy and critical dimensions. [Means for solving the problem]

[0009] According to a first aspect of the present invention, there is provided a charged particle multi-beam processing apparatus for exposing a target, which uses multiple beams of charged particles to write a desired pattern onto the target. The device comprises: a target stage configured to receive the target, the target having a predetermined overall area that includes an exposure region where the desired pattern is to be written; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Equipped with the target stage is configured to position the target at a specific location within a predetermined target plane and in a main direction defined within the target plane and relative to the plurality of particle-optical columns; the plurality of particle-optical columns are arranged along respective longitudinal axes that transverse (pass through) the target surface at respective origins; each particle-optical column projects its respective charged particle beam onto the target in a respective region around its respective origin to generate in said region a pattern sub-image corresponding to a portion of a pattern to be exposed on the target according to the position of the particle-optical column's respective origin in the target plane, said pattern sub-image having a lateral width measured in a direction transverse to said main direction, said lateral width being referred to as a "stripe width"; the charged particle multi-beam processing device is configured to cause relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern sub-images on the target, thereby moving the pattern sub-images across the target along respective paths along the main direction and writing exposure stripes on the target that extend substantially parallel to one another along the main direction; the plurality of particle-optical columns are arranged in a predetermined array with respect to their respective origins, the particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a longitudinal spacing measured along the main direction, and within each of the lines, in the case where the line includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset that is at least twice the stripe width; the apparatus is configured to repeat the process of writing an exposure stripe at least once, and preferably a plurality of times, each time at a lateral offset relative to a previous process of writing an exposure stripe, the lateral offset measured in a direction perpendicular to the main direction being less than or equal to the stripe width; and the apparatus is configured to reposition the target using the stage before each repetition according to a target repositioning path, the repositioning path including path portions that bypass origins of the plurality of particle-optical columns by moving the plurality of particle-optical columns relative to one another to positions where all origins of the particle-optical columns are located completely outside the exposure region or area of ​​the target. It is characterized by: According to a second aspect of the present invention, a method is provided for writing a desired pattern onto a target using a charged particle multi-beam processing apparatus. The device comprises: a target stage configured to receive and position a target having a predetermined overall area that includes an exposure region where the desired pattern is to be written within a predetermined target plane, the target plane having a defined main direction therein; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Including, The plurality of particle-optical columns are arranged along respective longitudinal axes that intersect (pass through) the target surface at respective origins, and the plurality of particle-optical columns are arranged according to a predetermined array with respect to their respective origins, the plurality of particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a longitudinal spacing measured along the main direction, and within each of the lines, when each of the lines includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset. The method comprises the steps of: using the target stage to position the target at a specific location in the target plane and relative to the plurality of particle-optical columns; projecting, in each particle-optical column, a respective charged particle beam onto the target in a respective region around a respective origin of the particle-optical column to generate in that region a pattern portion image corresponding to a portion of a pattern to be exposed on the target according to the position of the respective origin of the particle-optical column in the target plane, wherein the pattern portion image has a lateral width measured in a direction transverse to the main direction, referred to as a "stripe width", and the row offset is at least twice the stripe width if a line includes more than one particle-optical column; causing relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and imaging exposure stripes on the target that extend substantially parallel to one another along the main direction, wherein each exposure stripe is exposed by a single particle optical column or a group of two or more particle optical columns arranged along the main direction; containing, the steps are repeated, each time performed at a lateral offset measured perpendicular to the main direction relative to the previously completed step, the lateral offset being less than or equal to the stripe width to expose an exposure area on the target; The stage repositions the target between each repeat using a target repositioning path, the repositioning path including a path portion that bypasses the origins of the particle-optical columns by moving the particle-optical columns relatively to portions where all of the origins of the particle-optical columns are located completely outside the exposure region or the entire area of ​​the target. It is characterized by: DETAILED DESCRIPTION OF THE INVENTION

[0010] (Mode 1) See the above first aspect of the present invention. (Feature 2) In the device according to feature 1, The plurality of particle-optical columns are arranged in a rectangular array having n rows of particle-optical columns extending perpendicular to the line, each row containing m particle-optical columns, n≧1 and m≧2. is preferred. (Feature 3) In the device according to feature 1, The plurality of particle-optical columns are arranged in a staggered array having n rows of particle-optical columns, n≧1, and each row (each row) includes m≧2 columns; and between adjacent lines, the plurality of particle-optical columns are offset by a transversal offset that is less than the longitudinal spacing, or half the row offset, or 1 / m of the row offset. is preferred. (Feature 4) In the device according to any one of features 1 to 3, Each particle optical column is Irradiation system, a beam forming device; and Projection Optical System containing, the illumination system is configured to generate respective beams and shape the beams into substantially telecentric beams that illuminate shaping means, the beam shaping device is configured to shape the illumination beam into pattern portions comprised of a plurality of sub-beams, the pattern portions corresponding to portions of a pattern to be exposed on the target according to positions of respective origins of particle-optical columns in the target plane, and the projection optical system is configured to project images of the beam shapes defined in the shaping means onto the target, thereby forming the pattern portion images. is preferred. (Feature 5) See the second aspect of the present invention above. (Mode 6) In the method according to Mode 5, the exposure stripes are formed within a predetermined exposure area of ​​the target and across the exposure area along the main direction; The exposure stripes formed during each single traversal of the exposure area cover only a portion of the exposure area, and the formation of the exposure stripes is repeated offset from each other in a direction perpendicular to the main direction to cover the exposure area. is preferred. (Mode 7) In the method according to mode 5 or 6, the stripes drawn in all the repeats are drawn in consecutive order in at least two passes, each stripe belonging to exactly one of the passes; for each pass, the combined widths of the stripes in one pass cover a width of the exposure area measured in a direction transverse to said main direction; each pass being associated with one of a plurality of sub-grids of pattern pixels that can be exposed during the respective pass, the plurality of sub-grids being distinct from one another and that, when combined, combine to form a total number of pattern pixels that make up the pattern to be exposed in the exposure field; is preferred. (Embodiment 8) In the method according to embodiment 7, each particle-optical column contributing to writing a portion of the desired pattern in each of the at least two passes; is preferred. (Mode 9) In the method according to Mode 7, Each particle optical column contributes to the rendering of corresponding parts between passes. is preferred. (Mode 10) In the method according to Mode 7, Each pass is associated with one of a plurality of groups of particle optical columns, the plurality of groups of particle optical columns being separated from one another, and the stripes of each pass are exposed only by the particle optical columns of the respective associated group of particle optical columns. is preferred. (Mode 11) In the method according to any one of modes 7 to 10, During the writing of each single stripe, the particle-optical columns contribute the same stripe exposing the same partial grid at corresponding positions within each line, and the writing of the stripe is repeated to expose each of the plurality of partial grids. is preferred. (Mode 12) In the method according to any one of modes 5 to 11, With respect to grid rows (grid rows) of particle-optical columns formed by particle-optical columns positioned at corresponding positions within each line, during an exposure process for writing the desired pattern, for each row, selected particle-optical columns in each row are switched off during the exposure process, and the selected particle-optical columns in the rows correspond to one another with respect to the desired pattern being written. is preferred. (Mode 13) In the method according to Mode 12, The selection of particle-optical columns to be switched off is performed when a particle-optical column is detected to be defective or unsuitable for the imaging process, and the defective or unsuitable column is selected as one of the particle-optical columns to be switched off. is preferred. (Mode 14) In the method according to any one of modes 5 to 13, At least two stripes written by different columns partially overlap, to the extent that the overlap of the stripes with respect to the pattern pixels forming the desired pattern; nominal locations of pattern pixels of one of the two stripes overlap with nominal locations of corresponding pattern pixels of the other of the two stripes; and The pattern pixels are exposed in a complementary manner with respect to the desired pattern in at least two overlapping stripes. is preferred.

[0011] The above object is achieved by a charged particle multi-beam processing apparatus and a method for writing a desired pattern on a target using the apparatus as set forth in the appended claims. In particular, a first aspect of the present invention provides a charged particle multi-beam processing apparatus for exposing a target, in which a desired pattern is written on the target using multiple beams of charged particles. The target has a total area, and an exposure region in which the desired pattern is to be written is defined within the target area. The apparatus includes a target stage for receiving the target, and multiple particle optical columns configured to direct respective charged particle beams toward the target, thereby writing the desired pattern on the target.The target stage is configured to position the target relative to a plurality of particle-optical columns at specific locations within a given (predetermined) target plane and in a main direction defined within the target plane; the particle-optical columns are arranged (typically parallel to one another) along respective longitudinal axes that intersect (pass through) the target plane at respective (preferably different) origins, the particle-optical columns are arranged with respect to their respective origins according to a predetermined array (such as a rectangular array or a staggered array), the particle-optical columns form at least two (m≧2) lines within the array that extend perpendicular to the main direction and each line comprises at least one (preferably two or more) particle-optical column, and if any line comprises more than one particle-optical column (n≧2) within it, the particle-optical columns are spaced apart from one another, more precisely, offset relative to one another by a row offset (measured perpendicular to the main direction), and the lines are spaced apart from one another by a longitudinal spacing (measured along the main direction). spacing), and each particle optical column is configured to project its respective charged particle beam onto the target in a respective region around its respective origin to generate in that region a pattern sub-image corresponding to a portion of the pattern to be exposed on the target according to the position of the origin of the respective particle optical column in the target plane, the pattern sub-image having a lateral width, referred to as the "stripe width", measured transverse to the main direction, and the row offset being at least twice the stripe width (for n≧2; for lines where n=1 the row offset is inconsequential); the charged particle multi-beam processing apparatus is configured to cause relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns (simultaneously) generate the plurality of pattern sub-images on the target, thereby moving the pattern sub-images across the target along respective paths along the main direction and writing exposure stripes on the target that extend substantially parallel to each other along the main direction.

[0012] This solution provides an effective way to reduce the undesirable effects of charged particle leakage while maintaining extremely stringent requirements for patterning reliability and throughput. The invention involves the motion of the entire substrate (herein the terms "substrate" and "target" are used interchangeably) constantly relative to the columns, i.e., the motion of the stripes across the entire width of the substrate. As a result, the dose leaked due to charged particle leakage is uniformly distributed and applied along the stripes. Furthermore, the use of multiple stripes stitched along the writing direction can additionally help to achieve a uniform distribution of the leaked dose in the direction perpendicular to the stripes. In this case, it is obvious to readjust the nominal dose for the exposure to compensate for the effect of the leaked dose; in fact, the test exposure to determine the required nominal dose is already part of the normal calibration procedure, thus automatically taking this effect into account. Therefore, by using the described writing strategy with stripes formed (stitched) along the writing direction, it is possible to ensure accurate exposure dose throughout the pattern, thereby ensuring high pattern reliability of the writing process.

[0013] Many embodiments may provide for the exposure of mutually offset stripes. To this end, the above steps of the method may be repeated, each time offset by a lateral offset measured perpendicular to the main direction relative to the previously completed steps. The lateral offset is equal to or less than the width of a stripe to expose an exposure area on the target defined as the area where the desired pattern is to be written. Alternatively, the exposure stripes may be formed within a predetermined exposure area on the target by traversing (or scanning) the exposure area along the main direction. Here, the exposure stripes formed during each traversal of the exposure area cover only a portion of the exposure area, and the formation of the exposure stripes is repeated with respective offsets perpendicular to the main direction to cover the exposure area.

[0014] Furthermore, between each repeat, when the stage repositions the target, it may be advantageous for the stage to use a target repositioning path that bypasses the origins of the particle-optical columns, at least with respect to the exposure region. This further improves the reduction of undesired effects of charged particle leakage. In preferred embodiments, the repositioning path includes a path portion that bypasses the origins of the particle-optical columns by moving the particle-optical columns (as a relative motion between the target and the columns) to a location where all of the origins of the particle-optical columns are located completely outside the exposure region or area of ​​the target.

[0015] Generally, the exposure region (also referred to herein as the exposure area) is the portion of the target area that includes all areas of the target that are exposed to light to write a desired pattern on the target. In particular, if the target is a mask to be written, the exposure region will include all or at least a majority (e.g., at least approximately 90%) of the target area. As an alternative, in the case of a wafer target that includes multiple die fields, the exposure region is typically one of the die fields; although, if the writing method is expected to affect multiple die field patterns, it may be preferable to have the combination of all affected die fields as the exposure region in accordance with the present invention. In the latter case, the exposure region is the portion of the target area that includes all areas onto which the pattern is written.

[0016] In many embodiments of the device according to the present invention, each particle-optical column may advantageously comprise an illumination system, a beam shaping device and a projection optical system; the illumination system is configured to generate a beam in each case and to shape (convert) this beam into a substantially telecentric beam that illuminates the shaping means, the beam shaping device is configured to shape (convert) the shape of the illumination beam into pattern parts consisting of a number of sub-beams, which pattern parts correspond to parts of the pattern to be exposed on the target according to the location of each base point of the particle-optical column in the target plane, and the projection optical system is configured to project an image of the beam shape defined in the shaping means onto the target, thereby forming an image of said pattern part.

[0017] Furthermore, the apparatus can be configured to repeat the process of writing the exposure stripes at least once, and preferably multiple times, each time being performed at a lateral offset relative to each previous process of writing the exposure stripes, the lateral offset being less than or equal to the stripe width, measured perpendicular to the main direction.

[0018] Preferably, the particle-optical columns may be arranged in a rectangular array having n rows of particle-optical columns, each such row extending perpendicular to the direction of the lines and including m particle-optical columns, where n≧1 and m≧2. (Accordingly, m is the same as the number of lines.) In another preferred arrangement, the particle-optical columns may be arranged in a staggered array having n rows of particle-optical columns, where n≧1 and each such row includes m≧2 columns. Adjacent particle-optical columns within a row are offset by a transversal offset that is smaller than the column spacing (i.e., the spacing between adjacent lines), and the transversal offset is preferably half the row offset or 1 / m of the row offset. Often and more preferably, n≧2 and / or m≧2. Note that in the special case where n=1, one line reduces to containing just one particle-optical column, and the offset between adjacent such "lines" (each consisting of just one column) according to the column spacing is a component of the distance between the columns along the main direction.

[0019] The above objects are further achieved by a method for writing a desired pattern on a target using a charged particle multi-beam processing device, the device including a target stage configured to receive and position the target in a predetermined target plane, the target plane having a defined main direction therein, and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby writing the desired pattern on the target; the particle-optical columns are arranged (typically parallel to one another) along respective longitudinal axes that transverse (pass through) the target plane at respective (preferably different) origins, the particle-optical columns being arranged with respect to their respective origins according to a predetermined array (such as a rectangular array or a staggered array), in which the particle-optical columns form at least two lines extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, and the lines having a longitudinal spacing measured along the main direction. and within each line comprising two or more particle-optical columns (i.e., n>1), the particle-optical columns are spaced apart from one another according to a constant row offset, the method comprising the steps of: using a target stage to position the target at a specific location in the target plane and relative to the plurality of particle-optical columns; projecting, in each particle-optical column, a respective charged particle beam onto the target in a respective region around a respective fiducial point to generate, in said region, a pattern sub-image corresponding to a portion of the pattern to be exposed on the target according to the position of the respective fiducial point of the particle-optical column in the target plane, wherein the pattern sub-image has a lateral width measured in a direction transverse to the main direction, referred to as the "stripe width", and wherein the row offset (for lines with n>1) is at least twice the stripe width; causing relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns (simultaneously) generate a plurality of pattern sub-images on the target, thereby moving the pattern sub-images across the target along respective paths along the main direction and imaging exposure stripes on the target that extend substantially parallel to each other along the main direction, wherein each exposure stripe is exposed by one single particle optical column or one group of two or more particle optical columns arranged along the main direction; Includes.

[0020] This method according to the invention also offers the advantages mentioned above for the device of the invention. Further advantageous developments of the method include:

[0021] That is, in many embodiments, it may be preferable for the stripes written in the total number of repeats to be written in successive order in at least two passes, each stripe belonging to exactly one of the passes, the widths of the stripes in one pass for each pass combining to cover the width of the exposure field measured transverse to the main direction, and each pass being associated with one of a plurality of sub-grids of pattern pixels exposable during the respective pass, the sub-grids being distinct from one another and combining together to form the total number of pattern pixels that make up the pattern to be exposed in the exposure field.

[0022] In this case, it may be further advantageous if each particle optical column contributes to drawing portions of the desired pattern in each of at least two passes, preferably to corresponding drawing portions between passes. Another further development may provide that if each pass is associated with one of multiple groups of particle optical columns (the multiple groups of particle optical columns are disjoint from one another), the stripes of each pass are exposed only by the group of particle optical columns with which they are associated. Furthermore, the drawing process may additionally be configured such that, during drawing of each stripe, the particle optical columns of one row (i.e., the particle optical columns at corresponding positions within each line measured along the extension direction of the line) contribute to the same stripe exposing the same partial grid, and the drawing of the stripe is repeated to expose each of the multiple partial grids.

[0023] In another preferred development of the invention, during the exposure process for writing a desired pattern and with respect to grid rows of particle-optical columns formed by particle-optical columns positioned at corresponding positions in each line (measured in particular along the extension direction of the lines), one preferred approach to dealing with defects can be that, for each row, a selected particle-optical column of each row is switched off during the exposure process, the selected particle-optical columns of the rows corresponding to one another in terms of the desired pattern being written by writing exposure stripes. For example, if it is detected that a particle-optical column is defective (or unsuitable for the writing process), this defective column is selected as the particle-optical column to be switched off, particularly for the row of particle-optical columns to which this defective column belongs, and in each of the other rows, a particle-optical column of the respective row is selected to be switched off if the particle-optical column selected in this way corresponds to the defective column. Here, "corresponding particle optical columns" means that in a writing process involving writing exposure stripes, the particle optical columns "correspond" if they are writing portions of a desired pattern (possibly and preferably in different exposure stripes) simultaneously or at the same X position relative to the start of each stripe or within the same partial grid or any suitable combination thereof.

[0024] Additionally, some embodiments may employ an overlap margin for adjacent stripes. This may be achieved by implementing (configuring) the stripes so that at least two stripes written by different columns partially overlap, where, to the extent of the overlap of the stripes with respect to the pattern pixels forming the desired pattern, the nominal positions of the pattern pixels of one of the two stripes overlap with the nominal positions of the corresponding pattern pixels of the other of the two stripes, and the pattern pixels are exposed in a complementary manner with respect to the desired pattern in the at least two overlapping stripes.

[0025] In the following, exemplary and non-limiting embodiments are described which are diagrammatically illustrated in the drawings in order to further explain the invention. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a longitudinal cross-sectional view of an example of a multi-beam writer tool suitable for practicing the present invention; [Figure 2] 1 shows an example of a multi-column array according to an example of a regular rectangular array. [Figure 3] 10 shows another example of a multi-column array according to the example of a regular staggered array. [Figure 4A] 1 illustrates an exemplary exposure process for writing a pattern to a target, showing an array of columns in a staggered grid layout at the start of the exposure process. [Figure 4B] 1 shows an exemplary exposure process for writing a pattern to a target, with one intermediate position shown corresponding to approximately 60% of the total length along the X direction of the writing process. [Figure 4C] 1 shows a stage of an exemplary exposure process for writing a pattern to a target, showing the relative positions of the column array when the first stripes in each of the exposure fields are completed. [Figure 4D]1 shows an exemplary exposure process for writing a pattern to a target, showing the exposure of the second stripes of exposure fields along the X direction (shown at a position corresponding to approximately 10% of the total length of the writing). [Figure 4E] 1 shows a stage in an exemplary exposure process for writing a pattern to a target, with one configuration shown after the second stripes are completed. [Figure 5] A variation of the multi-column array of Figure 3. This includes deviations from the nominal positions of the regular grid due to limited precision in positioning. [Figure 6] 4A-4E illustrate examples of overlap margins implemented in a variation of the process of FIGS. 4A-4E. [Figure 7] FIG. 7 is a detail view of FIG. 6 illustrating the determination of appropriate parameters for the overlap margin. [Example]

[0027] The detailed description of exemplary embodiments of the present invention provided below discloses the basic idea, implementation, and further advantageous developments of the present invention. It should be clear to those skilled in the art to freely combine some or all of the embodiments described herein as deemed suitable for a particular application of the present invention. Throughout this disclosure, terms such as "advantageous," "exemplary," "typical," or "preferred" indicate elements or dimensions that are particularly suitable (but not essential) for the present invention or an embodiment thereof, but may be modified, if deemed appropriate by those skilled in the art, unless clearly essential. It should be understood that the present invention is not limited to the exemplary embodiments described below, which are provided for illustrative purposes and merely provide preferred implementations of the present invention. Within the scope of this disclosure, terms relating to the vertical direction, such as "up" or "down," should be understood with respect to the direction of a particle beam traversing (passing through) an electromagnetic lens, which is considered to extend downward ("vertically") along its central axis (or longitudinal axis). This longitudinal axis is generally identical to the Z direction, with the X and Y directions being the transverse (horizontal) axes.

[0028] Lithography equipment

[0029] In general, the present invention is suitable for general multi-column charged particle exposure tools, such as an array of variably shaped beam or Gaussian beam systems. In a preferred embodiment, the present invention is used in combination with a multi-column, multi-beam charged particle tool, such as the multi-column writer tool shown in schematic cross-section in Figure 1. The writer tool uses a charged particle beam formed from charged particles, which can be electrons or ions (e.g., positively charged ions).

[0030] The writer tool 101 includes a vacuum housing 110 for a multi-column charged particle optics 102, a target chamber 103 to which the multi-column charged particle optics is mounted by a column base plate 104. Within the target chamber 103 is an XY stage 105, e.g., an air-bearing vacuum stage controlled by a distance measurement system 121 and corresponding control unit 120, to which a substrate chuck 106, preferably an electrostatic chuck, is mounted using a suitable manipulation system. The chuck 106 holds a substrate 107 that serves as a target, such as a silicon wafer or photomask with an electron or ion beam sensitive resist layer.

[0031] The multi-column optical system 102 includes multiple particle-optical columns 109, preferably with the same configuration and arranged side-by-side with their axes parallel to one another. Each column includes an electron or ion source 111a, an extraction system 111b, and an electrostatic multi-electrode condenser optical system 111c. The illumination system 111 delivers a wide, telecentric charged particle beam to a pattern definition (PD) system 112, adapted to pass only through a number of apertures that define the shape of the sub-beams ("beamlets") transmitted through the apertures (beam shapers). The illumination system 111 also includes sequentially arranged electro-magneto-optical projector stages, preferably including electrostatic and / or magnetic lenses, and possibly other particle-optical devices. In the embodiment shown in FIG. 1, the projection optical system 116 includes a first lens 113, which is for example an accelerating electrostatic multi-electrode lens, while a second lens 114, located downstream of the first lens, is realized using an electromagnetic lens.

[0032] In each column 109, a first lens 113 of the projection optics forms a first crossover of the particle beam, while a second lens 114 forms a second crossover. In the second lens, a beam aperture 115 is configured to filter out beam portions that deviate from their respective optical axes due to deflection in the PD system. Each second lens 114 of the columns may be attached to a reference plate 117, which is preferably attached to the column base plate 104 by suitable fastening means 118. Attached to the reference plate 117 is a portion 119 of the off-axis optical alignment system. To position and shape the beam as it traverses the column, each column includes a multipole electrode system usable in conjunction with the projection optics. The writing multipole 122 serves, among other functions, to position the patterned beams of each column relative to each other and to the stage 105.

[0033] The reference plate is manufactured from a suitable base material with a low coefficient of thermal expansion, such as a ceramic material based on silicon oxide or aluminum oxide, which has the advantages of light weight, high modulus of elasticity and high thermal conductivity, and which can be suitably covered, at least in its relevant parts, with a conductive coating to prevent charging (by allowing static charge to be discharged).

[0034] The PD system 112 of each column serves to form from the particle beam a number of so-called beamlets, which contain the information of the pattern to be transferred to the target. The structure, operation and data processing of PD systems are disclosed in the applicant's US Pat. Nos. 9,443,699 and 9,495,499, the disclosures of which are incorporated herein by reference.

[0035] During the writing process at the target, specifically within the exposure region, which is the region of the target where the desired pattern is to be written, each particle-optical column generates an image of the PD system's apertures (pattern sub-images) on the target; thus, multiple pattern sub-images are generated and positioned at corresponding locations, or in practice, areas of limited size, on the target surface. These locations / areas are referred to as "beam fields" (shown as rectangles 42 in Figures 4A-4E). The writing process uses relative motion between the target and the array of particle-optical columns to generate a scanning motion of the pattern sub-images across the target surface. Thus, the beam field is moved across the target surface to write an exposure stripe, or "stripe" for short. It is important to note that for the writing process and in accordance with the present invention, only the relative motion between the target and the column is important; typically, the relative motion between the target and the array of particle-optical columns is achieved by moving the target and keeping the column fixed in place.

[0036] Multi-Column Architecture

[0037] 2 and 3 show examples of column arrangements suitable for the present invention, designed to write patterns in corresponding column exposure fields.

[0038] 2 shows a plan view of a rectangular layout of charged particle columns. The perimeter of each column is indicated by a black circle 21, and the area covered by its beam field is indicated by a small square 22 in the center of each circle 21 (the size of the squares is exaggerated for clarity, since in a typical implementation, the beam field 22 is significantly smaller than the width of the column's perimeter 21). In the illustrated example, the particle-optical columns are arranged in a regular rectangular grid, which includes n=3 grid rows (or rows) each containing m=3 particle-optical columns arranged along a main direction indicated by X in FIG. 2, with pitches DX and DY (the pitches DX and DY can be the same if the rectangular grid is a square grid); the center of each square 22 also represents the center of a corresponding particle-optical column positioned above, and preferably perpendicular to, the target plane. The arrangement of Figure 2 can also be understood as m = 3 grid lines extending along the Y direction of Figure 2 and each having n = 3 particle-optical columns; the grid lines are spaced apart by a longitudinal spacing DX measured along the X direction. The column offset DY within each line is also referred to as the row offset. It should be noted that the numbers n, m can be varied as needed for a particular implementation, e.g., n, m = 2, 3, 4, ... or powers of 2 (2 k, k>1) or multiples thereof. One particularly preferred implementation has, for example, m=2 and n=3. The exposure region or exposure area 20 on the target, which may be a wafer or a mask, is divided into a plurality of exposure fields 23 (shown by different types of hatching), each exposure field 23 being assigned to one or more rows of columns; in this case, each exposure field 23 is set to be exposed by the columns of the respective row. In Figure 2, the columns of each row are assigned to the same exposure field; this is also shown by the hatching, so that the beam fields of the rows have the same hatching.

[0039] To avoid confusion in terminology, the "columns" of a grid layout (extending along the Y direction in Figures 2-7) will be referred to as "grid column lines" or simply "column lines"; in contrast, the simple term "column" refers to a particle-optical column unless the context clearly dictates otherwise.

[0040] FIG. 3 illustrates another embodiment of the present invention. The columns, again represented by circles 26 with corresponding beam fields 25, are arranged in a staggered grid of (n=3)×(m=3) columns and pitches DX and DY. Here, a transversal offset DY / 3 exists between successive column lines. This allows the column exposure fields to be confined only along the Y direction, so that they form stripes 31 that together cover the complete exposure area 30. In this case, each column of the layout is assigned to a separate exposure field, as indicated by the different hatching for each of the exposure fields. It should be clear that the transversal offset can be selected differently in other embodiments, as appropriate for a particular writing strategy.

[0041] The selection of suitable values ​​for the column spacing DX and row offset DY will depend on the particular implementation, but will be subject to the mechanical constraints of the particle-optical column, such as the lateral width of the column footprint relative to the target surface. In this regard, Applicant's "slim" column lens implementation described in the above-mentioned US 2023 / 0015805 A1 allows for the inter-column spacing to be reduced to a typical value of 2 inches. For example, a six-column arrangement with n=3, m=2 or n=3[2], m=3 spacing is suitable when considering a typical substrate mask size of 6 inches. Of course, the spacing can be adapted (adjusted) as suitable for other implementations of the invention.

[0042] It should be noted that the positions described with respect to Figures 2 and 3 represent an idealized case in which the columns, i.e., their respective fiducials, are precisely positioned at ideal grid locations. In a more realistic scenario, the columns may have individual deviations from their grid locations due to limitations in construction accuracy. An example of such a more realistic case is shown in Figure 5, which shows an example of an array of columns with (exaggerated) deviations from their ideal grid locations; again, the columns are shown as black circles and their respective beam fields are shown as central squares 81. For example, the location of the central, top-most column 812 has offsets DDX2 and DDY2 along the X and Y directions, respectively, from its ideal location on the staggered grid indicated by the dashed circle and dashed square 80.

[0043] Multi-column drawing strategy

[0044] Exemplary writing strategies for a multi-column architecture for exposing a substrate are shown in Figures 4A-4E for basic writing strategies for ideal positions and Figures 9 and 10 for writing strategies including realistic positions slightly deviating from the ideal positions.

[0045] Figures 4A-4E show sequential stages of an exemplary exposure process using the staggered grid layout of Figure 3. It should be remembered that even though the diagrams in Figures 4A-4E deal with a fixed exposure area (reflecting a perspective focused on the pattern to be written on the target) and show the relative variable positions of the particle-optical columns as moving, it is the relative motion between the target and the array of particle-optical columns that is important. Figure 4A shows an example of an array of columns in a staggered grid layout at the start of the exposure process; the array is positioned in an initial position, so that all column beam fields 42 are outside the exposure area 40 (exposure region). The exposure area is divided (segmented) into multiple exposure fields, as can be seen in Figure 4A. The initial positions of the beam fields 42 are aligned with the respective starting edges of the exposure areas along the X direction (as shown by the dashed lines in FIG. 4A ); additionally, preferably, the beam fields of columns 413, 423, and 433 of the first column line (the rightmost column line in FIG. 4A ) are at the very edge of the exposure area 40, and all other column beam fields 42 are outside the exposure area 40. Starting from the arrangement shown in FIG. 4A , one stripe is exposed along the X direction. FIG. 4B shows one intermediate position corresponding to approximately 60% of the total length of the writing process along the X direction. The path of the beam field 42 of column 411 in the leftmost position (representative of the entire column array) is shown by dashed arrows for movement along the stripes within each exposure field, and solid arrows for movement along the stripes covering the area to be written. The other columns are fixed in arrangement because the entire column array moves as a block, so they move in the same way as column 42, but are offset horizontally from column 42.During movement along the stripes, the beam field of each column is manipulated by its respective PD system according to the desired pattern to be written on the target, thereby transferring the target pattern to the exposure field on the substrate. In FIG. 4B and subsequent FIGS. 4C-4E, the already patterned areas in the exposure area are indicated by gray stripes 51, and the columns are moved along a distance into the exposure area. FIG. 4C shows the relative positions of the column array when the first stripe in each exposure field is completed. The column arrangement then performs a half-turn, indicated by arrow 52, ​​to begin writing a second set of stripes, but in the opposite direction; i.e., in the negative X direction in the illustrated example. For example, FIG. 4D shows the process of exposing the second stripes of the exposure fields along the negative X direction (a position corresponding to approximately 10% of the total writing length is shown). Figure 4E shows the arrangement after the second stripe is completed; further, another reversal of the column array path is indicated by arrow 53, at which time exposure of the third stripe can begin. The above procedure is repeated until the stripes thus exposed cover the entire exposure area. During the reversal paths between successive stripes, indicated by the U-shaped dashed arrows 52, 53 in Figures 4D and 4E, all beam fields are moved completely outside the exposure area 40.

[0046] In other words, the paths include U-shaped turns, indicated by arrows 52 and 53, that ensure that the target is moved to a position that ensures that all beam fields 42 at the origins of the particle-optical columns 413-433 are moved (temporarily, i.e., each time between the writing of one stripe and the writing of the next) outside the exposure area 40. This helps to ensure that the array of beam fields is properly set up at the beginning and end of each stripe to be written; further, it ensures that each beam field has the same time duration above the exposure area 40 to minimize unequal heating, charging, and secondary effects on the target. In other words, this movement of the target helps to make the exposure area 40 bypass all origins 42 of the particle-optical columns 413-433.

[0047] In a preferred embodiment of the present invention, also shown in FIG. 3, successive column lines of the staggered grid transverse to the Y direction have a Y offset of DY / m, where m is the number of column lines in the grid (m=3 in FIG. 3, with an offset of DY / 3). This allows the exposure area to be completely covered by exposure fields each assigned to only a single column. Therefore, when multiple columns expose the same exposure field, the exposure area can be exposed more quickly than with the arrangement shown in FIG. 2, which does not have a Y offset between column lines. The former arrangement (FIG. 3) allows for increased throughput of the exposure tool. On the other hand, the latter redundant arrangement (FIG. 2) allows for increased precision and defect tolerance because: 1) non-systematic error contributions from all columns exposing the same exposure field are averaged out, resulting in a smaller final maximum error; and 2) one particularly selected column can become inoperable, e.g., if it malfunctions, while the other columns exposing the same exposure field can compensate without a loss of throughput.

[0048] It should be noted, however, that in many embodiments of the present invention, the pitches DY and DY / m may be inconsistent with the beam array field width, and therefore may not be an integer multiple of the beam array field width. Thus, the target pattern area of ​​at least one of the stripes in an exposure sequence may have a width that is smaller than the beam array field width.

[0049] For a rectangular column grid layout including multiple column lines (e.g., three column lines, i.e., three particle optical columns per row, m=3), m particle optical columns are assigned to each exposure field, all of which expose the same exposure area by writing their respective stripes. The exposure sequence is similar to that described above and in FIGS. 4A to 4E , except that in this case the offset along the Y direction is zero. Furthermore, each column is enabled to reduce the total dose deposited (applied) to the substrate for pattern formation by a factor of m, by a factor of m. The original target dose for the pattern is then delivered to the substrate. Of course, for any type of array grid layout, including the layouts of FIGS. 2 and 3 , it is also possible to perform the writing procedure according to a multiple-pass exposure strategy, as described in the applicant's U.S. Pat. No. 9,053,906.

[0050] In example realistic scenarios, the precision of the mutual positioning of the columns will be limited. For example, it may be possible at best to position the columns with an accuracy of a few tens of micrometers, so the pitches DX and DY and the associated offsets will not be exactly equal to the distance between adjacent columns. For the purposes of this invention, the pitch and offset are considered equal if any deviation from the nominal column positions is greater than the deflection range that the beam deflection means of the columns can achieve; this deflection range is typically several hundred nanometers. Beam deflection means are generally used to keep the beam array fixed at its target position during the exposure process while the substrate is continuously moved along the writing direction. Furthermore, they can also be used to compensate for various placement errors, including those described in other patents by the applicant, such as U.S. Pat. No. 10,325,756, but which generally do not include column arrangement errors.

[0051] FIG. 5 illustrates the staggered column arrangement of FIG. 3. In this figure, exemplary offsets from the nominal positions are also shown. In particular, dashed lines indicate the nominal positions of the columns and beam fields 80 for a regular staggered grid with constant pitch DX and DY and Y offset, while the corresponding actual positions are shown in solid lines (i.e., solid circles and solid squares 81). The "first" column 811 is used as a reference, so its actual position coincides with its nominal position. The actual position offset from the nominal position is shown in FIG. 5 only for the example of the central top column 812, i.e., offset distances DDX2 and DDY2 for column 812. In the following, to simplify the notation, columns are numbered with a simple index i (i=1...9 for the 3x3 arrangement of FIGS. 3 and 5), and the offset from the nominal position for the ith column is denoted as DDX i and DDY i The actual Y offset between the ith and kth columns is defined as DY i,k For example, DY 2,3indicates the actual Y offset between the second and third columns.

[0052] For this slightly distorted column arrangement, it may not be possible to cover the entire exposure area with a writing sweep without adapting the area and / or number of stripes exposed by the columns. For example, as shown in FIG. 5, DDY2 is positive and DDY3 is negative, so DY 2,3 is larger than DY, which may require at least one additional stripe to write the area between the two columns i=2 and i=3. During the exposure of the additional stripe, the column i=1 will pass through (cross) areas already exposed by the column i=2, and it may be advantageous to switch off its beam in such areas to avoid overlapping exposures.

[0053] Overlap Margin

[0054] A method for writing parallel stripes is described in the applicant's US 8,378,320. To further improve the transition of features across the boundary between adjacent exposed stripes, even when butting errors are likely to occur, US 8,378,320 proposes an exposure method based on overlap margins but using an improved strategy in the context of multi-beam exposure. This mechanism of overlap margins described above is adapted (or adjusted) as described below for writing with multi-column multi-beam exposure.

[0055] 6, although overlap margins can be provided at the edges of the exposure fields (instead of stripes), typically two overlap margins are provided, one at each edge of one exposure field. For example, the exposure field 91 associated with column i=1 has an overlap margin B 01 and B 12The margin B is expanded by the addition of EF1, so that it effectively has the width indicated by EF1. 12 also indicates the corresponding overlap margin of the adjacent exposure field EF2. By overlapping the two overlap margins of adjacent exposure fields EF1,...,EF9, a continuous image pattern can be reproduced on the target. k ,EF k+1 Within the overlap on the target defined by the overlap margins, the exposure is performed in the first of the two exposure fields. k The overlap margin is partially executed in the course (or stroke) of the exposure, and the second EF k+1 The two column exposures are performed partially in the course (or stroke) of the exposure (overlap margin); the two column exposures are combined to produce a complete exposure corresponding to the main part of the exposure field (i.e. the area of ​​the exposure field without overlap).

[0056] The above description implies that the exposure fields are covered in stripes during the exposure process, and that any part of a stripe or even of multiple stripes may fall within the overlap margin of an exposure field.

[0057] As described in US 8,378,320 (and unlike US 7,129,024), the method according to the present invention divides the pixels to be exposed on the target by assigning each pixel in the overlap region to one of the overlap margins that are superimposed at each location, so that the dose value of each pixel exposed remains unchanged regardless of which exposure field produces the pixel.

[0058] Further details regarding overlap margins can be found in US 8,378,320, the disclosure of which regarding overlap margins is incorporated herein by reference.

[0059] Referring to FIG. 7 (showing only the top three columns of the layout of FIG. 6), the exposure field and the individual overlap margins on both sides can be defined as follows: First, the offset DY i to the maximum offset value DY max , i.e., DY max =max i DY i Determine this value DY max is used as the expanded exposure field size for each column. Then, for each exposure area, the maximum column deviation DDY from their nominal grid position is used. max =max i DDY i The upper edge of each enlarged exposure field is aligned with the start position 101 of the column, and the upper edge of each enlarged exposure field is aligned with the start position 101 of the column. max The far bottom edge is aligned with its end position 102 .

[0060] The overlap margin between adjacent stripes allows for a reduction in butting errors between adjacent stripes or exposure fields written by each column: systematic errors occurring along the boundary (or transition) between two columns or stripes will be reduced by "mixing" the pattern portions written by the different columns or stripes, thereby smoothing the transition from one exposure field to the next, as explained in detail in the above-mentioned US 8,378,320. Furthermore, additional stripes can be inserted at the top and bottom of a contiguous patch of stripes covering the pattern, so that the leaked dose is uniform across the entire pattern.

[0061] Although the present invention has been described in terms of specific embodiments for illustrative purposes, it should be apparent that the present invention may be readily adapted by those skilled in the art to other embodiments without departing from the scope of the present invention as set forth in the appended claims.

[0062] All or part of the above embodiments and examples can be described as the following supplementary notes, but are not limited thereto. [Appendix 1] A charged particle multi-beam processing apparatus for target exposure, which writes a desired pattern on a target using multiple beams of charged particles. The device comprises: a target stage configured to receive the target, the target having a predetermined overall area that includes an exposure region where the desired pattern is to be written; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Equipped with the target stage is configured to position the target at a specific location within a predetermined target plane and in a main direction defined within the target plane and relative to the plurality of particle-optical columns; The particle-optical columns are arranged along respective longitudinal axes that transverse (pass through) the target surface at respective origins. each particle-optical column projects its respective charged particle beam onto the target in a respective region around its respective origin to generate in said region a pattern sub-image corresponding to a portion of a pattern to be exposed on the target according to the position of the particle-optical column's respective origin in the target plane, said pattern sub-image having a lateral width measured in a direction transverse to said main direction, referred to as a "stripe width"; the charged particle multi-beam processing device is configured to cause relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and writing exposure stripes on the target that extend substantially parallel to one another along the main direction; the plurality of particle-optical columns are arranged in a predetermined array with respect to their respective origins, the particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a longitudinal spacing measured along the main direction, and within each of the lines, in the case where the line includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset that is at least twice the stripe width; The apparatus is configured to repeat the process of writing an exposure stripe at least once, and preferably multiple times, each time shifted by a lateral offset relative to a previous process of writing an exposure stripe, wherein the lateral offset measured in a direction perpendicular to the main direction is less than or equal to the stripe width, and is configured to reposition the target using the stage before each repetition according to a target repositioning path, the repositioning path including a path portion that bypasses the origins of the multiple particle-optical columns by moving the multiple particle-optical columns relatively to positions where all origins of the particle-optical columns are located completely outside the exposure region or entire area of ​​the target. [Appendix 2] In the device according to Appendix 1, The plurality of particle-optical columns are arranged in a rectangular array having n rows of particle-optical columns extending perpendicular to the line, each row containing m particle-optical columns, where n≧1 and m≧2. [Appendix 3] In the above-mentioned device, particularly the device described in Appendix 1, The plurality of particle-optical columns are arranged in a staggered array having n rows of particle-optical columns, where n≧1, and each row (each row) includes m≧2 columns; and between adjacent lines, the plurality of particle-optical columns are offset by a transversal offset that is less than the longitudinal spacing or half the row offset or 1 / m of the row offset. [Appendix 4] In the above-mentioned device, particularly the device described in any one of Appendices 1 to 3, Each particle optical column is Irradiation system, a beam forming device; and Projection Optical System Contains; the illumination system is configured to generate respective beams and shape them into substantially telecentric beams that illuminate a shaping means; the beam shaping device is configured to shape the illumination beam into pattern portions consisting of a plurality of sub-beams, the pattern portions corresponding to portions of the pattern to be exposed on the target according to positions of respective origins of particle-optical columns in the target plane; and the projection optical system is configured to project an image of the beam shape defined in the shaping means onto the target, thereby forming the pattern portion images. [Appendix 5] A method for writing a desired pattern on a target using a charged particle multi-beam processing apparatus. The device comprises: a target stage configured to receive and position a target having a predetermined overall area that includes an exposure region where the desired pattern is to be written within a predetermined target plane, the target plane having a defined main direction therein; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Including, The plurality of particle-optical columns are arranged along respective longitudinal axes that intersect (pass through) the target surface at respective origins, and the plurality of particle-optical columns are arranged according to a predetermined array with respect to their respective origins, the plurality of particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a longitudinal spacing measured along the main direction, and within each of the lines, when each of the lines includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset. The method comprises the steps of: using the target stage to position the target at a specific location in the target plane and relative to the plurality of particle-optical columns; projecting, in each particle-optical column, a respective charged particle beam onto the target in a respective region around a respective origin of the particle-optical column to generate in that region a pattern portion image corresponding to a portion of a pattern to be exposed on the target according to the position of the respective origin of the particle-optical column in the target plane, wherein the pattern portion image has a lateral width measured in a direction transverse to the main direction, referred to as a "stripe width", and the row offset is at least twice the stripe width if a line includes more than one particle-optical column; causing relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and imaging exposure stripes on the target that extend substantially parallel to one another along the main direction, wherein each exposure stripe is exposed by a single particle optical column or a group of two or more particle optical columns arranged along the main direction; Includes. the steps are repeated, each time performed at a lateral offset measured perpendicular to the main direction relative to the previously completed step, the lateral offset being less than or equal to the stripe width to expose an exposure area on the target; Between each repeat, the stage repositions the target using a target repositioning path, which includes a path portion that bypasses the origins of the plurality of particle-optical columns by moving the plurality of particle-optical columns relatively to a location or locations where all of the origins of the particle-optical columns are located completely outside the exposure region or the entire area of ​​the target. [Appendix 6] In the method according to Appendix 5, the exposure stripes are formed within a predetermined exposure area of ​​the target and across the exposure area along the main direction; The exposure stripes formed during each single traversal of the exposure area cover only a portion of the exposure area, and the formation of exposure stripes is repeated, each offset in a direction perpendicular to the main direction to cover the exposure area. [Appendix 7] In the above method, particularly the method according to appendix 5 or 6, The stripes drawn in all the repeats are drawn in a consecutive order in at least two passes, each stripe belonging to exactly one of the passes; For each pass, the combined widths of the stripes in one pass cover the width of the exposure area measured in a direction transverse to said main direction; Each pass is associated with one of a plurality of partial grids of pattern pixels that can be exposed during the respective pass, the partial grids being different from one another and, when taken together, combining into a total number of pattern pixels that make up the pattern to be exposed in the exposure area. [Appendix 8] In the above method, particularly the method described in Appendix 7, Each particle-optical column contributes to imaging a portion of the desired pattern in each of the at least two passes. [Appendix 9] In the above method, particularly the method described in Appendix 7, Each particle optical column contributes to the imaging of a corresponding portion between passes. [Appendix 10] In the above method, particularly the method described in Appendix 7, Each pass is associated with one of a plurality of groups of particle optical columns, the plurality of groups of particle optical columns being separated from one another, and the stripes of each pass are exposed only by the particle optical columns of the respective associated group of particle optical columns. [Appendix 11] In the above method, particularly in the method according to any one of Appendices 7 to 10, During the writing of each single stripe, the particle-optical columns contribute the same stripe exposing the same partial grid at corresponding positions within each line, and the writing of the stripe is repeated to expose each of the multiple partial grids. [Appendix 12] In the above method, particularly in the method according to any one of Appendices 5 to 11, For a plurality of grid rows (grid rows) of particle-optical columns formed by particle-optical columns positioned at corresponding positions within each line, during the exposure process for writing the desired pattern, for each row, selected particle-optical columns in each row are switched off during the exposure process; the selected particle-optical columns in the rows correspond to each other with respect to the desired pattern being written. [Appendix 13] In the above method, particularly the method described in Appendix 12, The selection of particle-optical columns to be switched off is performed when a particle-optical column is detected to be defective or unsuitable for the imaging process, and the defective or unsuitable column is selected as one of the particle-optical columns to be switched off. [Appendix 14] In the above method, particularly in the method according to any one of Appendices 5 to 13, At least two stripes written by different columns partially overlap; to the extent that the stripes overlap with respect to the pattern pixels forming the desired pattern, Nominal locations of pattern pixels of one of the two stripes overlap with nominal locations of corresponding pattern pixels of the other of the two stripes; and Pattern pixels are exposed in at least two overlapping stripes in a complementary manner with respect to the desired pattern.

[0063] [Appendix 1'] A charged particle multi-beam processing apparatus for target exposure, which writes a desired pattern on a target using multiple beams of charged particles. The device comprises: a target stage configured to receive the target; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Equipped with the target stage is configured to position the target at a specific location within a predetermined target plane and in a main direction defined within the target plane and relative to the plurality of particle-optical columns; The particle-optical columns are arranged along respective longitudinal axes that transverse (pass through) the target surface at respective origins. Each particle-optical column projects its respective charged particle beam onto the target in a respective region around its respective origin, generating in that region a pattern portion image corresponding to the portion of the pattern to be exposed on the target according to the position of the particle-optical column's respective origin in the target plane, the pattern portion image having a lateral width measured in a direction transverse to the main direction referred to as the "stripe width". The charged particle multi-beam processing device is configured to cause relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and writing exposure stripes on the target that extend substantially parallel to each other along the main direction. The plurality of particle-optical columns are arranged in a predetermined array with respect to their respective origins, the particle-optical columns form at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to each other according to a longitudinal spacing measured along the main direction, and within each of the lines, in the case where the line includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from each other according to a constant row offset that is at least twice the stripe width. The apparatus is configured to repeat the process of writing an exposure stripe at least once, and preferably multiple times, each time shifted by a lateral offset relative to a previous process of writing an exposure stripe, the lateral offset measured in a direction perpendicular to the main direction being less than or equal to the stripe width, and to reposition the target using the stage before each repetition, at least with respect to the exposure region, according to a target repositioning path that bypasses the origins of the plurality of particle-optical columns. [Appendix 2'] In the device according to appendix 1', The plurality of particle-optical columns are arranged in a rectangular array having n rows of particle-optical columns extending perpendicular to the line, each row containing m particle-optical columns, where n≧1 and m≧2. [Appendix 3'] In the device according to appendix 1', The plurality of particle-optical columns are arranged in a staggered array having n rows of particle-optical columns, where n≧1, and each row (each row) includes m≧2 columns; and between adjacent lines, the plurality of particle-optical columns are offset by a transversal offset that is less than the longitudinal spacing, preferably half the row offset or 1 / m of the row offset. [Appendix 4'] In the device according to any one of appendices 1' to 3', Each particle optical column is Irradiation system, a beam forming device; and Projection Optical System Including, the illumination system is configured to generate respective beams and shape them into substantially telecentric beams that illuminate a shaping means; the beam shaping device is configured to shape the illumination beam into pattern portions consisting of a plurality of sub-beams, the pattern portions corresponding to portions of the pattern to be exposed on the target according to positions of respective origins of particle-optical columns in the target plane; and the projection optical system is configured to project an image of the beam shape defined in the shaping means onto the target, thereby forming the pattern portion images. [Appendix 5'] A method for writing a desired pattern on a target using a charged particle multi-beam processing apparatus. The device comprises: a target stage configured to receive and position the target within a predetermined target plane, the target plane having a main direction defined therein; and a plurality of particle-optical columns configured to direct respective charged particle beams at the target, thereby imaging the desired pattern on the target; Including, The plurality of particle-optical columns are arranged along respective longitudinal axes that intersect (pass through) the target surface at respective origins, and the plurality of particle-optical columns are arranged according to a predetermined array with respect to their respective origins, the plurality of particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a longitudinal spacing measured along the main direction, and within each of the lines, when each of the lines includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset. The method comprises the steps of: using the target stage to position the target at a specific location in the target plane and relative to the plurality of particle-optical columns; projecting, in each particle-optical column, a respective charged particle beam onto the target in a respective region around a respective origin of the particle-optical column to generate in that region a pattern portion image corresponding to a portion of a pattern to be exposed on the target according to the position of the respective origin of the particle-optical column in the target plane, wherein the pattern portion image has a lateral width measured in a direction transverse to the main direction, referred to as a "stripe width", and the row offset is at least twice the stripe width if a line includes more than one particle-optical column; causing relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and imaging exposure stripes on the target that extend substantially parallel to one another along the main direction, wherein each exposure stripe is exposed by a single particle optical column or a group of two or more particle optical columns arranged along the main direction; Includes. The steps are repeated, each time performed at a lateral offset measured perpendicular to the main direction relative to the previously completed step, where the lateral offset is less than or equal to the stripe width, to expose an exposure area on the target. The stage repositions the target between each repeat, at least with respect to the exposure region, using a target repositioning path that bypasses origins of the plurality of particle-optical columns. [Appendix 6'] In the method according to Appendix 5', The exposure stripes are formed within a predetermined exposure area of ​​the target and across the exposure area along the main direction; The exposure stripes formed during each single traversal of the exposure area cover only a portion of the exposure area, and the formation of exposure stripes is repeated, each offset in a direction perpendicular to the main direction to cover the exposure area. [Appendix 7'] In the method according to appendix 5' or 6', The stripes drawn in all the repeats are drawn in a consecutive order in at least two passes, each stripe belonging to exactly one of the passes; For each pass, the combined widths of the stripes in one pass cover the width of the exposure area measured in a direction transverse to said main direction; Each pass is associated with one of a plurality of partial grids of pattern pixels that can be exposed during the respective pass, the partial grids being different from one another and, when taken together, combining into a total number of pattern pixels that make up the pattern to be exposed in the exposure area. [Appendix 8'] In the method according to Appendix 7', Each particle-optical column contributes to imaging portions of the desired pattern in each of the at least two passes, preferably corresponding portions between passes. [Appendix 9'] In the method according to Appendix 7', Each pass is associated with one of a plurality of groups of particle optical columns, the plurality of groups of particle optical columns being separated from one another, and the stripes of each pass are exposed only by the particle optical columns of the respective associated group of particle optical columns. [Appendix 10'] In the method according to any one of Appendices 7' to 9', During the writing of each single stripe, the particle-optical columns contribute the same stripe exposing the same partial grid at corresponding positions within each line, and the writing of the stripe is repeated to expose each of the multiple partial grids. [Appendix 11'] In the method according to any one of Appendices 5' to 10', For a plurality of grid rows (grid rows) of particle-optical columns formed by particle-optical columns positioned at corresponding positions within each line, during the exposure process for drawing the desired pattern, for each row, selected particle-optical columns in each row are switched off during the exposure process, and the selected particle-optical columns in the rows correspond to each other with respect to the desired pattern being drawn. [Appendix 12'] In the method according to Appendix 11', The selection of particle-optical columns to be switched off is performed when a particle-optical column is detected to be defective or unsuitable for the imaging process, and the defective or unsuitable column is selected as one of the particle-optical columns to be switched off. [Appendix 13'] In the method according to any one of Appendices 5' to 12', At least two stripes written by different columns partially overlap, and to the extent that the overlap of the stripes with respect to the pattern pixels forming the desired pattern, nominal locations of pattern pixels of one of the two stripes overlap with nominal locations of corresponding pattern pixels of the other of the two stripes; and Pattern pixels are exposed in at least two overlapping stripes in a complementary manner with respect to the desired pattern.

[0064] Within the scope of the entire disclosure of the present invention (including the claims and drawings), modifications and adjustments of the embodiments are possible based on the basic technical concept thereof. Furthermore, within the scope of the entire disclosure of the present invention, various combinations and selections (including "non-selection") of various disclosed elements (including each element of each claim, each element of each embodiment, each element of each drawing, etc.) are possible. In other words, the present invention naturally includes various modifications and alterations that would be possible by a person skilled in the art in accordance with the entire disclosure, including the claims and drawings, and the technical concept of the present invention. In particular, with regard to the numerical ranges described herein, any numerical value or subrange included within the range should be construed as being specifically described, even if not otherwise specified.

[0065] Furthermore, the reference numerals in the drawings attached in the claims are intended solely to aid in the understanding of the invention and are not intended to limit the invention to the embodiments and examples shown.

[0066] Furthermore, the entire contents of each of the above references are incorporated herein by reference.

Claims

1. A charged particle multi-beam processing apparatus (1) for exposing a target (107), which writes a desired pattern on the target (107) using multiple beams of charged particles, comprising: The device comprises: a target stage (105) configured to receive the target; and a plurality of particle-optical columns (109) configured to direct respective charged particle beams toward the target (107), thereby imaging the desired pattern on the target; Equipped with the target stage (105) is configured to position the target at a specific location within a predetermined target plane and in a main direction defined within the target plane and relative to the plurality of particle-optical columns; the plurality of particle-optical columns (109) are arranged along respective longitudinal axes transverse to the target surface at respective origins; each particle-optical column (109) projects a respective charged particle beam onto the target in a respective region around a respective fiducial point to generate in said region a pattern sub-image corresponding to a portion of a pattern to be exposed on the target according to the position of the respective fiducial point of the particle-optical column in the target plane, said pattern sub-image having a lateral width measured in a direction transverse to said main direction, said lateral width being referred to as a "stripe width"; the charged particle multi-beam processing device is configured to cause relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and writing exposure stripes on the target that extend substantially parallel to one another along the main direction; the plurality of particle-optical columns (109) are arranged in a predetermined array with respect to their respective origins, the particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a column spacing measured along the main direction, and within each of the lines, in the case where the line includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset that is at least twice the stripe width; the apparatus is configured to repeat the process of writing an exposure stripe at least once, and preferably a plurality of times, each time at a lateral offset with respect to a previous process of writing an exposure stripe, the lateral offset measured perpendicular to the main direction being less than or equal to the stripe width, and to reposition the target using the stage before each repetition, at least with respect to the exposure region, according to a target repositioning path that bypasses origins of the plurality of particle-optical columns. An apparatus characterized by:

2. 10. The apparatus of claim 1, the plurality of particle-optical columns are arranged in a rectangular array having n rows of particle-optical columns extending perpendicular to the line, each row containing m particle-optical columns, n≧1 and m≧2; An apparatus characterized by:

3. 10. The apparatus of claim 1, the plurality of particle-optical columns are arranged in a staggered array having n rows of particle-optical columns, n≧1, and each row (each row) includes m≧2 columns; and between adjacent lines, the plurality of particle-optical columns are offset by a transversal offset that is less than the column spacing, preferably half the row offset or 1 / m of the row offset. A device characterized by:

4. In the device according to any one of claims 1 to 3, Each particle optical column (109) an illumination system (111); a beam shaping device (112), and Projection optical system (116) containing, the illumination system (111) is configured to generate respective beams and shape them into substantially telecentric beams that illuminate a shaping means; the beam shaping device (112) is configured to shape the illumination beam into pattern portions consisting of a plurality of sub-beams, the pattern portions corresponding to portions of a pattern to be exposed on the target according to positions of respective origins of a particle-optical column in the target plane; and the projection optical system (116) is configured to project images of the beam shapes defined in the shaping means onto the target (107), thereby forming the pattern portion images. A device characterized by:

5. 1. A method for writing a desired pattern on a target using a charged particle multi-beam processing apparatus, comprising: The device comprises: a target stage (105) configured to receive and position the target within a predetermined target plane, the target plane having a main direction defined therein; and a plurality of particle-optical columns (109) configured to direct respective charged particle beams toward the target (107), thereby imaging the desired pattern on the target; Including, the plurality of particle-optical columns (109) are arranged along respective longitudinal axes transverse to the target surface at respective base points, and the plurality of particle-optical columns (109) are arranged according to a predetermined array with respect to the respective base points, the plurality of particle-optical columns forming at least two lines in the array extending perpendicular to the main direction, each of the at least two lines including at least one particle-optical column, the lines being offset relative to one another according to a column spacing measured along the main direction, and within each of the lines, in the case where each of the lines includes two or more particle-optical columns, the plurality of particle-optical columns are spaced apart from one another according to a constant row offset; The method comprises the steps of: positioning the target at a specific location in the target plane and relative to the plurality of particle-optical columns using the target stage (105); projecting, in each particle-optical column (109), a respective charged particle beam onto the target in a respective region around a respective fiducial point to generate in said region a pattern sub-image corresponding to a portion of the pattern to be exposed on the target according to the position of the respective fiducial point of the particle-optical column in the target plane, wherein said pattern sub-image has a lateral width measured transverse to said main direction, referred to as a "stripe width", and wherein said row offset is at least twice said stripe width if a line comprises more than one particle-optical column; causing relative motion between the target and the plurality of particle optical columns along the main direction while the plurality of particle optical columns generate a plurality of pattern portion images on the target, thereby moving the pattern portion images across the target along respective paths along the main direction and imaging exposure stripes on the target that extend substantially parallel to one another along the main direction, wherein each exposure stripe is exposed by a single particle optical column or a group of two or more particle optical columns arranged along the main direction; containing, the steps are repeated, each time performed at a lateral offset measured perpendicular to the main direction from the previously completed step, the lateral offset being less than or equal to the stripe width to expose an exposure area on the target; The stage repositions the target between each repeat, at least with respect to the exposure region, using a target repositioning path that bypasses origins of the plurality of particle-optical columns. A method characterized by:

6. 6. The method of claim 5, the exposure stripes are formed within a predetermined exposure area of ​​the target and across the exposure area along the main direction; the exposure stripes formed during each single crossing of the exposure area cover only a portion of the exposure area, and the formation of the exposure stripes is repeated with each exposure stripe being offset in a direction perpendicular to the main direction to cover the exposure area. A method characterized by:

7. 7. The method according to claim 5 or 6, the stripes drawn in all the repeats are drawn in consecutive order in at least two passes, each stripe belonging to exactly one of said passes; for each pass, the combined widths of the stripes in one pass cover the width of the exposure area measured in a direction transverse to said main direction; each pass being associated with one of a plurality of sub-grids of pattern pixels that can be exposed during the respective pass, the plurality of sub-grids being distinct from one another and that, when combined, combine to form a total number of pattern pixels that make up the pattern to be exposed in the exposure field; A method characterized by:

8. 8. The method of claim 7, Each particle-optical column contributes to writing a portion of the desired pattern in each of the at least two passes, preferably corresponding portions between passes. A method characterized by:

9. 8. The method of claim 7, Each pass is associated with one of a plurality of groups of particle optical columns, the plurality of groups of particle optical columns being separated from one another, and the stripes of each pass are exposed only by the particle optical columns of the respective associated group of particle optical columns. A method characterized by:

10. The method according to any one of claims 7 to 9, During the writing of each single stripe, the particle-optical column contributes the same stripe exposing the same partial grid at corresponding positions within each line, and the writing of the stripe is repeated to expose each of the plurality of partial grids. A method characterized by:

11. The method according to any one of claims 5 to 10, for grid rows of particle-optical columns formed by particle-optical columns positioned at corresponding positions within each line, during an exposure process for drawing the desired pattern, selected particle-optical columns in each row are switched off during the exposure process, and the selected particle-optical columns in the rows correspond to one another with respect to the desired pattern being drawn; A method characterized by:

12. 12. The method of claim 11, The selection of the particle optical column to be switched off is performed when it is detected that a particle optical column is defective or unsuitable for the drawing process, and the defective or unsuitable column is selected as one of the particle optical columns to be switched off. A method characterized by:

13. The method according to any one of claims 5 to 12, At least two stripes written by different columns partially overlap, and to the extent that the stripes overlap with respect to the pattern pixels forming the desired pattern, the nominal positions of the pattern pixels of one of the two stripes overlap with the nominal positions of the corresponding pattern pixels of the other of the two stripes; and The pattern pixels are exposed in a complementary manner with respect to the desired pattern in at least two overlapping stripes. A method characterized by:

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