Multi-electron beam lithography device and multi-electron beam lithography method

Abstract

A device capable of suppressing changes in the influence of the Coulomb effect during a shot in multi-beam writing is provided. [Configuration] A drawing device 100 according to one embodiment of the present invention is characterized by comprising a multi-photoelectron source 10 that emits a multi-photoelectron beam, a photoelectron source control circuit 131 that controls the multi-photoelectron source so that, for each shot of the multi-photoelectron beam, all photoelectron beams that become ON beams among the multi-photoelectron beams in that shot have a common irradiation time and the individual beam current of each photoelectron beam is maintained constant during the shot, and a drawing mechanism 150 that draws a pattern on a sample using the multi-photoelectron beam whose individual beam current is maintained constant during the shot.

Description

[Technical Field]

[0001] One aspect of the present invention relates to a multi-electron beam lithography apparatus and a multi-electron beam lithography method, for example, an electron beam lithography apparatus and an electron beam lithography method using a multi-photoelectron source. [Background technology]

[0002] Lithography technology, which is responsible for the advancement of miniaturization of semiconductor devices, is the only extremely important process in semiconductor manufacturing that generates patterns. In recent years, with the increasing integration density of LSIs, the circuit line width required for semiconductor devices has been getting finer year by year. Here, electron beam (EB) lithography technology has inherently excellent resolution, and mask patterns are written onto mask blanks using an electron beam.

[0003] For example, there is a lithography system that uses multiple beams. Compared to lithography using a single electron beam, using multiple beams allows for the irradiation of many beams at once, thereby significantly improving throughput. In such a multi-beam lithography system, for example, an electron beam emitted from an electron gun is passed through a shaping aperture array substrate with multiple holes to form multiple beams, each of which is blanked and each beam not blocked by the limiting aperture is reduced in size by an optical system, the mask image is reduced in size, and the beam is deflected by a deflector to be irradiated onto the desired position on the sample.

[0004] In conventional multi-beam lithography, the dose of each beam is controlled by its irradiation time. Each shot irradiates a small area (pixel) corresponding to each beam of the multi-beam system with a predetermined dose. Therefore, during each shot, a beam is turned off when its scheduled irradiation time is reached, even if other beams remain on. This causes the number of ON beams to change during the shot, resulting in a change in the total beam current. This can change the influence of the Coulomb effect and result in errors in the beam distribution on the sample surface. Another method, for example, involves operating a common blanker when switching the number of ON beams during a shot (see, for example, Patent Document 1). In this case, a shot includes a period when all beams are turned off, and the number of ON beams remains unchanged during this period. However, a short beam ON period is included to achieve the desired dose. In this case, the number of ON beams changes during the shot, resulting in a change in the total beam current, potentially resulting in the same problems as described above. Therefore, it is desirable to suppress changes in the influence of the Coulomb effect during the shot.

[0005] Here, a technology has been disclosed in which the beams that are turned ON are assigned to one of multiple groups depending on the total current value of the beam group, and the shot order is changed so that shots assigned to the same group are irradiated consecutively, thereby suppressing changes in the influence of the Coulomb effect (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-112639 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-220491 Summary of the Invention [Problem to be solved by the invention]

[0007] One aspect of the present invention provides an apparatus and method capable of suppressing changes in the influence of the Coulomb effect during a shot in multi-beam writing. [Means for solving the problem]

[0008] A multi-electron beam lithography apparatus according to one aspect of the present invention includes: a multi-photoelectron source that emits multiple photoelectron beams; a control circuit that controls the multi-photoelectron source so that, for each shot of the multi-photoelectron beam, all photoelectron beams that become ON beams among the multi-photoelectron beams in that shot have a common irradiation time, and so that individual beam currents of the photoelectron beams are maintained constant during the shot period; a writing mechanism for writing a pattern on a sample using multiple photoelectron beams, each of which has its individual beam current maintained constant during a shot period; The present invention is characterized by the following features.

[0009] In addition, the multi-photoelectron source a plurality of light sources that output a plurality of lights; an electron source array that receives a plurality of light beams and thereby emits multiple photoelectron beams; and a value of the beam current of each photoelectron beam of the multi-photoelectron beams is controlled by the intensity of light received by a corresponding electron source of the electron source array; The control circuit preferably has a plurality of amplifiers that control the plurality of light sources so that each light source individually outputs a light intensity corresponding to a plurality of gradations that define the dose.

[0010] Alternatively, the multi-photoelectron source may be a plurality of light sources that output a plurality of lights; an electron source array that receives a plurality of light beams and thereby emits multiple photoelectron beams; and each electron source of the electron source array is arranged to be able to receive light from two or more light sources; a value of the beam current of each photoelectron beam of the multi-photoelectron beam is controlled by the number of lights received by a corresponding electron source of the electron source array; The control circuit preferably has a plurality of switch circuits that individually switch the number of light sources that output light to the corresponding electron source so that each electron source individually receives a number of lights corresponding to a plurality of gradations that define the dose.

[0011] It is also preferable that the electron optical system has a correction lens that corrects the focal position of the multiple photoelectron beams for each shot.

[0012] The sample is also multiply drawn with a multiplicity of N, The intensity of the light received by each electron source is controlled in n gradations, including zero. The dose at each irradiation position on the sample surface irradiated with the multiple photoelectron beams is preferably controlled in (N·(n−1)+1) gradations, including zero.

[0013] The sample is placed on a movable stage, Tracking control is performed so that the irradiation area of ​​the beam array that constitutes the multi-photoelectron beam follows the movement of the stage. During each tracking operation, multiple shots are taken with different irradiation positions. a sorting processing unit that sorts, for each tracking operation, the total beam current of each of a plurality of shots performed during the tracking operation in descending or ascending order; a drawing control unit that controls a drawing operation so that a plurality of shots are performed in a sorted order for each tracking operation; It is preferable that the device further comprises:

[0014] The multi-photoelectron source further includes a shaping aperture array substrate for shaping the multi-photoelectron beams emitted from the multi-photoelectron source, Preferably, the sample is illuminated with multiple shaped photoelectron beams.

[0015] A multi-electron beam writing method according to one aspect of the present invention includes: emitting multiple photoelectron beams from a multiple photoelectron source; controlling the multi-photoelectron source so that, for each shot of the multi-photoelectron beam, all photoelectron beams that become ON beams among the multi-photoelectron beams in that shot have a common irradiation time and the individual beam currents of the photoelectron beams are maintained constant during the shot period; writing a pattern on a specimen using multiple photoelectron beams, each with an individual beam current maintained constant during the shot; The present invention is characterized by the following features. [Effects of the Invention]

[0016] According to one aspect of the present invention, it is possible to eliminate changes in the number of ON beams during a shot period, thereby suppressing changes in the influence of the Coulomb effect during the shot period. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a conceptual diagram showing a configuration of a drawing device according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of a multi-photoelectron source according to the first embodiment. [Figure 3] FIG. 3 is a diagram showing another example of the configuration of the multi-photoelectron source according to the first embodiment. [Figure 4] FIG. 2 is a diagram for explaining a method of controlling a dose amount in the first embodiment. [Figure 5] FIG. 2 is a conceptual diagram for explaining an example of a drawing operation in the first embodiment. [Figure 6] 3 is a diagram showing an example of a multi-beam irradiation area and a pixel to be written in the first embodiment. FIG. [Figure 7] FIG. 2 is a diagram for explaining an example of a multi-photoelectron beam writing operation in the first embodiment. [Figure 8] FIG. 10 is a diagram showing an example of the total beam current for each shot before sorting in the first embodiment. [Figure 9]FIG. 10 is a diagram showing an example of the total beam current for each shot after sorting processing in the first embodiment. [Figure 10] FIG. 10 is a cross-sectional view showing an example of the configuration of a part of an electron source array in a modified example of the first embodiment. [Figure 11] FIG. 10 is a top view showing an example of the configuration of a part of an electron source array in a modified example of the first embodiment. [Figure 12] FIG. 10 is a diagram showing an example of a photoelectron source control circuit in a modified example of the first embodiment. [Figure 13] FIG. 10 is a conceptual diagram showing the configuration of a drawing device according to a second embodiment. [Figure 14] FIG. 10 is a conceptual diagram showing the configuration of a shaping aperture array substrate in the second embodiment. [Figure 15] FIG. 11 is a conceptual diagram showing the configuration of a drawing device according to a third embodiment. [Figure 16] FIG. 11 is a conceptual diagram showing the configuration of a shaping aperture array substrate according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Embodiment 1 FIG. 1 is a conceptual diagram showing the configuration of a lithography apparatus according to the first embodiment. In FIG. 1, the lithography apparatus 100 includes a multi-photoelectron source mechanism 201, a lithography mechanism 150, and a control circuit 160. The lithography apparatus 100 is an example of a multi-charged particle beam lithography apparatus. The lithography mechanism 150 includes an electron column 102 (multi-electron beam column) and a lithography chamber 103. Inside the electron column 102, an electromagnetic lens 205, a deflector 213, a limiting aperture substrate 206, a correction lens 214, an electromagnetic lens 207 (objective lens), a deflector 209, and a deflector 208 are arranged. The multi-photoelectron source mechanism 201 is arranged at the top inside the electron column 102.

[0019] An XY stage 105 is arranged in the patterning chamber 103. A sample 101, such as a mask blank coated with resist, which serves as a patterning target substrate during patterning, is arranged on the XY stage 105. The sample 101 includes an exposure mask used in manufacturing a semiconductor device, a semiconductor substrate (silicon wafer) on which the semiconductor device is manufactured, and the like. In addition, a mirror 210 is arranged on the XY stage 105.

[0020] The inside of the electron lens barrel 102 and the inside of the drawing chamber 103 are evacuated by a vacuum pump (not shown) and are controlled to a pressure lower than atmospheric pressure.

[0021] In the multi-photoelectron source mechanism 201, the multi-photoelectron source 10, the electrode group 12, and the photoelectron source control circuit 131 are arranged in a housing 106. The electrode group 12 includes a plurality of electrodes 12a, 12b, 12c, and 12d, each having an opening at the center through which the multi-photoelectron beams 20 can pass. While the example in FIG. 1 shows a four-stage electrode group, the present invention is not limited thereto. Five or more stages are also possible, or three or fewer stages are also possible. The housing 106 is formed, for example, of an insulator. This configuration can suppress discharge from the electrode group 12. The interior of the housing 106 is evacuated by a vacuum pump (not shown) and controlled to a pressure lower than atmospheric pressure. An opening for the passage of the multi-photoelectron beams is formed in the lower part of the housing 106. It is preferable that the interior of the housing 106, from which the multi-photoelectron beams 20 are emitted, be maintained at a lower pressure than the other spaces in the electron microscope column 102.

[0022] The control circuit 160 includes a control computer 110, a memory 112, a deflection control circuit 130, digital-to-analog conversion (DAC) amplifier units 132 and 134, a lens control circuit 136, an accelerating electrode control circuit 137, a stage control circuit 138, a stage position measurement device 139, and storage devices 140 and 142 such as magnetic disk drives. The control computer 110, the memory 112, the deflection control circuit 130, the lens control circuit 136, the accelerating electrode control circuit 137, the stage control circuit 138, the stage position measurement device 139, and storage devices 140 and 142 are connected to one another via a bus (not shown). The deflection control circuit 130 is connected to the DAC amplifier units 132 and 134 and the photoelectron source control circuit 131. The sub-deflector 209 is composed of four or more electrodes, and each electrode is controlled by the deflection control circuit 130 via the DAC amplifier unit 132. The main deflector 208 is configured with four or more electrodes, and each electrode is controlled by a deflection control circuit 130 via a DAC amplifier unit 134. A lens group including the electromagnetic lenses 205 and 207 is controlled by a lens control circuit 136.

[0023] For example, an electrostatic lens or an electromagnetic lens can be used as the correction lens 214. When an electrostatic lens is used as the correction lens 214, the electrostatic lens is composed of, for example, three stages of electrode substrates. A ground potential is applied to the upper and lower stage electrode substrates. A control potential is applied to the middle stage electrode substrate from an electrostatic lens control circuit (not shown). When an electromagnetic lens is used as the correction lens 214, it is controlled by the lens control circuit 136.

[0024] The multi-photoelectron source 10 in the multi-photoelectron source mechanism 201 is controlled by a photoelectron source control circuit 131. The electrode group 12 is controlled by an acceleration electrode control circuit 137.

[0025] The position of the XY stage 105 is controlled by driving motors (not shown) for each axis controlled by a stage control mechanism 138. A stage position measuring device 139 receives light reflected from a mirror 210 and measures the position of the XY stage 105 based on the principle of laser interferometry.

[0026] The control computer 110 includes a data processing unit 50, a current amount calculation unit 52, a sorting unit 54, a drawing control unit 72, and a transfer processing unit 74. Each of the "units" such as the data processing unit 50, the current amount calculation unit 52, the sorting unit 54, the drawing control unit 72, and the transfer processing unit 74 has a processing circuit. Such a processing circuit may include, for example, an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device. Each of the "units" may use a common processing circuit (the same processing circuit) or different processing circuits (separate processing circuits). Information input / output to and from the data processing unit 50, the current amount calculation unit 52, the sorting unit 54, the drawing control unit 72, and the transfer processing unit 74, as well as information being calculated, is stored in the memory 112 each time.

[0027] The drawing operation of the drawing apparatus 100 is controlled by a drawing control unit 72. Furthermore, the transfer process of the dose data for each shot to the deflection control circuit 130 is controlled by a transfer processing unit 74.

[0028] Furthermore, drawing data (chip data) is input from outside the drawing device 100 and stored in the storage device 140. The chip data defines information on a plurality of figure patterns that constitute the chip pattern. Specifically, for each figure pattern, for example, the coordinates of each vertex are defined in the order in which the figure is constituted. Alternatively, for example, a figure code, coordinates, size, etc. may be defined for each figure pattern.

[0029] 1 shows the configuration necessary for explaining the first embodiment. The drawing device 100 may also include other configurations that are normally required.

[0030] Fig. 2 is a diagram showing an example of the configuration of the multi-photoelectron source in embodiment 1. In Fig. 2, the multi-photoelectron source 10 has a light source array 14, a lens array 16, an electron source array 40, an outer peripheral wall 45, an extraction electrode 44, and an angle-limiting aperture array 46. It is desirable to provide the angle-limiting aperture array 46, but it may be omitted.

[0031] The light source array 14 has a substrate 13 and a plurality of light sources 15. A plurality of openings are formed in an array on the substrate 13, and a light source 15 is disposed in each opening. For example, an LED is preferably used as the light source 15. The plurality of light sources 15 output a plurality of laser beams.

[0032] The lens array 16 is configured so that lenses are arranged at positions where the laser beams 11 output from the light sources 15 pass.

[0033] The electron source array 40 has a glass substrate 41, a plurality of electron sources 42, and a light-shielding film 43. The light-shielding film 43 is disposed on the light source array 14 side (front side) of the glass substrate 41. Each electron source 42 is disposed on the opposite side (rear side) of the glass substrate 41 from the light source array 14 side. Each electron source 42 is preferably disposed on the optical axis of the corresponding light source 15, for example. Lanthanum hexaboride (LaB6), for example, is preferably used as the electron source 42. The electron source array 40 receives a plurality of laser beams and thereby emits a multi-photoelectron beam 20.

[0034] The laser light 11 output from each light source 15 is collected by a corresponding lens in the lens array 16 and passes through the glass substrate 41. Each laser light 11 that has passed through the glass substrate 41 is reflected by an extraction electrode 44 and enters the back surface of the corresponding electron source 42. The extraction electrode 44 functions as a mirror that reflects the laser light in addition to functioning as an extraction electrode. Of the laser light collected by the lens, the light beams other than the light beams that enter the back surface of the electron source 42 are blocked by a light-shielding film 43 on the surface of the glass substrate 14. Therefore, a film pattern of the light-shielding film 43 is formed in the region where the light beams other than the light beams that enter the back surface of the electron source 42 enter the glass substrate 41.

[0035] The photoelectron source control circuit 131 is provided with a plurality of amplifiers 80 and a control circuit 81. Each light source 15 generates laser light 11 with an intensity controlled by the photoelectron source control circuit 131. The value of the beam current of each photoelectron beam of the multi-photoelectron beam 20 is controlled by the intensity of light received by the corresponding electron source 42. The plurality of amplifiers 80 controlled by the control circuit 81 control the plurality of light sources 15 so that each light source 15 individually outputs laser light 11 with an intensity corresponding to a plurality of gradations that define the irradiation amount (dose). In this way, the intensity of the laser light 11 of each light source 15 is controlled by the output of the corresponding amplifier 80 controlled by the control circuit 81.

[0036] An acceleration voltage is applied to each electron source 42 by the photoelectron source control circuit 131. For example, a potential of −50 kV is applied. Furthermore, a potential more positive than the acceleration voltage is applied to the extraction electrode 44 by the photoelectron source control circuit 131. For example, a potential of −49.9 kV is applied. Each electron source 42 is irradiated with the laser light 11 and emits a photoelectron beam. The photoelectron beam emitted from each electron source 42 is accelerated by the extraction electrode 44, forms a crossover, and then passes through the extraction electrode 44 while spreading in the divergence direction. As a result, multiple photoelectron beams 20 are formed.

[0037] In the extraction electrode 44, openings are formed at the positions where each photoelectron beam passes. Gold (Au) or the like is preferably used for the extraction electrode 44. Since the multiple photoelectron beams 20 that pass through the multiple openings in the extraction electrode 44 spread in the divergence direction, the emission angle of each photoelectron beam can be adjusted (limited) by passing the multiple photoelectron beams through openings in an angle-limiting aperture array 46, which has openings formed at the positions where each photoelectron beam passes.

[0038] Here, in order for each electron source 42 to emit photoelectrons, it is desirable that the environment of each electron source 42 be a high vacuum environment. On the other hand, the electron source array 40 is surrounded by the glass substrate 41, the outer peripheral wall 45, and the angle-limiting aperture array 46, and the conductance tends to be low when evacuating the interior. Therefore, as shown in Fig. 2, it is preferable to make evacuation easier by forming an opening in the outer peripheral wall 45, for example. It is also preferable to form the evacuation opening in the angle-limiting aperture array 46.

[0039] 1, the multi-photoelectron beams 20 that have passed through the forming angle limiting aperture array 46 are accelerated by the electrode group 12 and emitted from the multi-photoelectron source mechanism 201. A potential is applied to each of the electrodes 12 so that the potentials become relatively more positive. From the multi-photoelectron source 10 side, a potential of, for example, −30 kV is applied to the electrode 12a, a potential of, for example, −20 kV to the electrode 12b, a potential of, for example, −10 kV to the electrode 12c, and a ground (GND) potential to the electrode 12d.

[0040] Fig. 3 is a diagram showing another example of the configuration of the multi-photoelectron source according to the embodiment 1. Fig. 3 is the same as Fig. 2 except that a plurality of optical fibers 18 (optical fiber bundles) are used instead of the plurality of light sources 15 mounted on the light source array 14. In this way, it is also preferable to emit a photoelectron beam by irradiating the electron source 42 with the laser light 11 generated from the optical fiber 18.

[0041] FIG. 4 is a diagram illustrating a method of controlling the dose in the first embodiment. The example in FIG. 4 shows an example of a multi-photoelectron beam 20 consisting of 3×3 photoelectron beams. In the first embodiment, the dose to each pixel 36 is controlled not by the length of the irradiation time at a constant beam current but by the magnitude of the beam current at a constant irradiation time. The example in FIG. 4 shows, for example, beam currents (relative values) normalized to a preset reference beam current of 1 corresponding to the dose of each photoelectron beam in the multi-photoelectron beam 20. The example in FIG. 4 shows beam current values ​​of 0.6, 0.8, 1.0, 0.4, 0.0, 1.0, 0.8, 0.2, and 0.4. Therefore, the total beam current (total beam current) of the entire multi-photoelectron beam 20 is 5.2. In the first embodiment, for each shot, all photoelectron beams that become ON beams in the multi-photoelectron beam 20 share a common irradiation time Ttr, and the individual beam currents of each photoelectron beam are maintained constant during the shot. In the example of Figure 4, the individual beam currents of 0.6, 0.8, 1.0, 0.4, 0.0, 1.0, 0.8, 0.2, and 0.4 are maintained during the shot period. This prevents any photoelectron beams from switching from ON to OFF before the shot period is completed, and all beams are simultaneously switched OFF at the end of the shot period. In this way, the number of ON beams can be prevented from changing during the shot period. This makes it possible to suppress changes in the total beam current. This also makes it possible to suppress changes in the influence of the Coulomb effect during the shot period.

[0042] Next, a specific example of the operation of the writing mechanism 150 will be described. The multi-photoelectron beams 20 emitted from the multi-photoelectron source mechanism 201 are refracted by the electromagnetic lens 205 and reduced in size in the focusing direction. They then travel toward a central hole formed in a limiting aperture substrate 206 located near the crossover position. After passing through the limiting aperture substrate 206, the multi-photoelectron beams 20 are focused by the objective lens 207 to form a pattern image with the desired reduction ratio. The entire multi-photoelectron beams 20 are deflected in the same direction by the main deflector 208 and the sub-deflector 209, and each beam is irradiated onto its respective irradiation position on the sample 101. Furthermore, for example, when the XY stage 105 is moving continuously, the main deflector 208 performs tracking control so that the beam irradiation position follows the movement of the XY stage 105. Ideally, the multi-photoelectron beams 20 irradiated at one time are arranged at a pitch obtained by multiplying the arrangement pitch of the multiple holes 22 in the shaping aperture array substrate 203 by the desired reduction ratio.

[0043] Furthermore, by collectively deflecting the entire multi-photoelectron beam 20 using the deflector 213, the entire deflected multi-photoelectron beam 20 can be blocked by the limiting aperture substrate 206, turning the beam OFF. Conversely, by not collectively deflecting the entire multi-photoelectron beam 20 using the deflector 213, the beam can be turned ON by passing through the limiting aperture substrate 206. The multi-photoelectron source 10 can arbitrarily control ON / OFF of each beam of the multi-photoelectron beam 20, but blanking control using the deflector 213 can precisely align the irradiation time of the entire multi-photoelectron beam 20. In other words, by blanking control using the deflector 213, one shot of the multi-photoelectron beam 20 is formed by a group of photoelectron beams that pass through the limiting aperture substrate 206 from when the beam is turned ON until when the beam is turned OFF.

[0044] FIG. 5 is a conceptual diagram illustrating an example of the writing operation in the first embodiment. As shown in FIG. 5, the writing region 30 on the sample 101 is virtually divided into a plurality of stripe regions 32, each having a predetermined width in the y direction. First, the XY stage 105 is moved to adjust the irradiation region 34 that can be irradiated with a single shot of the multi-photoelectron beam 20 to the left end of the first stripe region 32, or to a position further to the left, and writing begins. When writing the first stripe region 32, the XY stage 105 is moved, for example, in the −x direction to relatively write in the x direction. The XY stage 105 is moved continuously, for example, at a constant speed. After writing the first stripe region 32, the stage position is moved in the −y direction to adjust the irradiation region 34 to the right end of the second stripe region 32, or to a position further to the right, relative to the y direction. Then, the XY stage 105 is moved, for example, in the x direction, to similarly write in the −x direction. The writing time can be reduced by alternately changing the direction of writing, such as writing in the x direction in the third stripe region 32 and writing in the -x direction in the fourth stripe region 32. However, writing is not limited to alternately changing the direction of writing, and writing in the same direction may be performed for each stripe region 32. Multiple writing is also suitable for writing. Multiple writing may involve repeatedly writing the same stripe region 32 without shifting the position, or by setting the stripe region 32 for each pass while shifting the position. In such multiple writing, multiple writing is performed by multiple stage movements (passes) (multiple-pass multiple writing). Alternatively, multiple writing may be performed at the same position with different beams of the multi-photoelectron beam 20 during a single stage movement (intra-pass multiple writing).

[0045] FIG. 6 shows an example of a multi-beam irradiation area and a target pixel for writing in the first embodiment. In FIG. 6, the stripe area 32 is divided into a plurality of mesh areas, for example, based on the beam size of the multiple photoelectron beams 20. Each mesh area corresponds to a target pixel 36 (beam irradiation unit area, irradiation position). The center of each pixel 36 corresponds to a control grid 27 that controls the irradiation position of each beam. The size of the target pixel 36 is not limited to the beam size and may be any size regardless of the beam size. For example, the size may be 1 / n (n is an integer greater than or equal to 1) of the beam size. The example in FIG. 6 shows a case where the target region for writing on the sample 101 is divided, for example, in the y direction, into a plurality of stripe areas 32, each having a width substantially equal to the size of the irradiation region 34 (writing field) that can be irradiated with one irradiation of the multiple beams 20. The size of the rectangular irradiation region 34 in the x direction can be defined as the number of beams in the x direction multiplied by the beam pitch in the x direction. The size of the rectangular irradiation area 34 in the y direction can be defined by the number of beams in the y direction times the inter-beam pitch in the y direction. In the example of FIG. 6, for example, a 512×512 array of multi-photoelectron beams is shown abbreviated to an 8×8 array of multi-photoelectron beams. A plurality of pixels 28 (beam drawing positions) that can be irradiated with a single shot of the multi-photoelectron beam 20 are shown within the irradiation area 34. The pitch between adjacent pixels 28 is the inter-beam pitch of each of the multi-beams. A rectangular area surrounded by the size of the inter-beam pitch in the x and y directions constitutes one sub-irradiation area 29 (pitch cell area). In the example of FIG. 6, each sub-irradiation area 29 is composed of, for example, 4×4 pixels.

[0046] In the dose calculation step, the writing data processing unit 50 first reads writing data from the storage device 140, for example, for each stripe region 32, and calculates, for each pixel 36, the pattern area density ρ of the figure pattern to be arranged within that pixel 36 (rasterization process). The writing data processing unit 50 then calculates the dose D to be applied to that pixel 36. The dose D may be calculated, for example, by multiplying a preset reference dose Dbase by a proximity effect-corrected dose Dp and the pattern area density ρ. The proximity effect-corrected dose Dp is defined as a relative value normalized with the reference dose Dbase set to 1. Thus, the dose D is preferably calculated in proportion to the pattern area density calculated for each pixel 36. To calculate the proximity effect-corrected dose Dp, the writing region (e.g., the stripe region 32) is virtually divided into a plurality of proximity mesh regions (mesh regions for proximity effect correction calculation) of a predetermined size in a mesh pattern. The size of the proximity mesh region is preferably set to approximately 1 / 10 of the range of influence of the proximity effect, for example, approximately 1 μm. Then, the drawing data is read from the storage device 140, and for each proximity mesh region, the pattern density ρ′ (pattern area density) of the pattern to be arranged in the proximity mesh region is calculated.

[0047] Next, a proximity effect correction dose Dp for correcting the proximity effect is calculated for each proximity mesh region. Here, the size of the mesh region for calculating the proximity effect correction dose Dp does not need to be the same as the size of the mesh region for calculating the pattern density ρ'. Furthermore, the correction model for the proximity effect correction dose Dp and its calculation method may be the same as the method used in the conventional single-beam writing method.

[0048] In the first embodiment, writing is performed once at each position on the sample 101, or multiple writing is performed twice or more with a multiplicity N, where N is an integer equal to or greater than 2. When multiple writing is performed, it is preferable to use, for example, a value obtained by dividing the calculated dose D by the multiplicity N as the irradiation dose in each writing process.

[0049] In the beam current calculation step, the current amount calculation unit 52 calculates the beam current per preset common irradiation time Ttr of the multiple photoelectron beams 20 for each pixel 36. The beam current (current density) can be calculated by dividing the irradiation amount D by the common irradiation time Ttr. When multiple writing is performed, the writing data processing unit 50 calculates the beam current for each pixel for each writing process of multiple writing. Then, the current amount calculation unit 52 creates a beam current map using the calculated beam current for each pixel as an element.

[0050] The calculated beam current data for each pixel is stored in the storage device 142 in shot order.

[0051] FIG. 7 is a diagram illustrating an example of a multi-photoelectron beam writing operation in the first embodiment. The example of FIG. 7 illustrates a case where writing is performed with four different photoelectron beams in each sub-irradiation region 29, each of which includes one beam irradiation position of the multi-photoelectron beam 20 and is surrounded by the inter-beam pitch. The example of FIG. 7 also illustrates a writing operation in which the XY stage 105 continuously moves at a speed of a distance L equivalent to eight beam pitches while writing is performed on a quarter (one-fourth of the number of beams used for irradiation) region in each sub-irradiation region 29. In the writing operation illustrated in the example of FIG. 7, for example, while the XY stage 105 moves the distance L equivalent to eight beam pitches, the sub-deflector 209 sequentially shifts the irradiation positions (pixels 36), thereby writing (exposing) four different pixels 36 in the same sub-irradiation region 29 with the same beam.

[0052] In FIG. 7, the settling time between shots is omitted, and the shot cycle is shown as the common irradiation time Ttr in the first embodiment.

[0053] During the drawing (exposure) of these four pixels 36, the main deflector 208 deflects the entire multi-photoelectron beam 20 collectively so that the irradiation area 34 follows the movement of the XY stage 105, preventing the relative position of the irradiation area 34 to the sample 101 from shifting due to the movement of the XY stage 105. In other words, tracking control is performed. When one tracking cycle is completed, tracking is reset, and the deflection position of the irradiation area 34 returns to the previous tracking start position. Note that the example of FIG. 7 shows a case where one row of 4×4 pixels in each sub-irradiation area 29 is drawn in each tracking cycle. However, this is not limited to this. The pixels to be drawn in each tracking cycle can be selected in groups of four as long as they do not overlap.

[0054] When drawing one row at a time in each tracking cycle, drawing of the first pixel row from the right in each sub-irradiation area 29 is completed in the first tracking operation, so after tracking is reset, in the next tracking cycle, the sub-deflector 209 first deflects the beam to align (shift) the drawing position so that drawing of an undrawn pixel row, for example, the second pixel row from the right, in each sub-irradiation area 29 is drawn. By repeating this operation during drawing of the stripe area 32, the position of the irradiation area 34 of the multi-beam 20 moves sequentially to 34a, 34b, 34c, ..., and drawing is performed, as shown in the lower diagram of Figure 5.

[0055] In the first embodiment, for example, four shots are performed during each tracking operation in order of increasing (or decreasing) beam current in the entire multi-photoelectron beam 20. This will be specifically described below.

[0056] As a sorting process, the sorting processing unit 54 calculates, for each shot, the total beam current of the entire multi-photoelectron beam 20 in that shot. Then, for each tracking operation, the sorting processing unit 54 sorts the total beam current of each of the multiple shots performed during that tracking operation in descending or ascending order.

[0057] 8 is a diagram showing an example of the total beam current for each shot before sorting in the first embodiment. The example in Fig. 8 shows a case where, for example, four shots are performed for each tracking operation. Compared to the first shot, the second shot is smaller, the third shot is between the first and second shots, and the fourth shot is sufficiently small.

[0058] 9 is a diagram showing an example of the total beam current of each shot after the sorting process in the first embodiment. FIG. 9 shows a case where the order of each shot is rearranged in descending order. The example in FIG. 9 shows a case where, for example, four shots are performed for each tracking operation. The first shot is the first pixel in descending order (the first shot pixel in FIG. 8), the second shot is the second pixel in descending order (the third shot pixel in FIG. 8), the third shot is the third pixel in descending order (the second shot pixel in FIG. 8), and the fourth shot is the fourth pixel in descending order (the fourth shot pixel in FIG. 8).

[0059] In the writing process, first, the transfer processing unit 74 transfers data on the beam current values ​​of the target pixels 36 in shot order to the deflection control circuit 130. Under the control of the writing control unit 72, the deflection control circuit 130 outputs data on the beam current values ​​of the target pixels 36 to the photoelectron source control circuit 131 in shot order.

[0060] The photoelectron source control circuit 131 (control circuit) controls the multi-photoelectron source 10 so that, for each shot of the multi-photoelectron beam 20, all photoelectron beams that become ON beams among the multi-photoelectron beam 20 in that shot have a common irradiation time Ttr, and the individual beam current of each photoelectron beam is maintained constant during the shot period.

[0061] In the first embodiment, the beam current of each photoelectron beam is controlled by the output of laser light from the light source 15 that irradiates the electron source 42, which emits the photoelectron beam. The beam current of each photoelectron beam is proportional to the intensity of the laser light that irradiates the electron source 42. The intensity of the laser light is proportional to the current value from the amplifier 80 that is input to the light source 15. Therefore, the intensity of the laser light, and therefore the beam current of the photoelectron beam, can be controlled by the resolution of the amplifier output.

[0062] The intensity of light received by each electron source 42 is controlled in n gradations, including zero. When drawing is performed once at each position on the sample 101, it is controlled in ((n-1)+1) gradations, including zero. For example, if there are eight levels with a maximum value of 1.6 in increments of 0.2, control is possible in n=9 gradations, including the minimum value of zero. In this case, the quantization unit is set so that the maximum value of 1.6 becomes the maximum beam current value per drawing process across the entire drawing region 30.

[0063] Furthermore, when multiple drawing is performed N times, control is performed using (N·(n-1)+1) gradations, including zero. For example, when multiple drawing is performed N=8 times, the maximum is 12.8 (=1.6×8), which can be defined as 65 (=8×(9-1)+1) gradations in steps of 0.2. In this case, the quantization unit is set so that the maximum value of 1.6 across the entire drawing area 30 is the maximum beam current value per drawing process for multiple drawing.

[0064] Alternatively, in the case of 128 types with a maximum of 25.6 in 0.2 increments, control can be performed with n=129 gradations, including the minimum value of zero. If multiple drawing is performed N=8 times, 1025 (=8×(129-1)+1) gradations can be defined. In this case, the quantization unit is set so that the maximum value of 25.6 becomes the maximum beam current value per drawing process of multiple drawing across the entire drawing area 30.

[0065] As a result, in the writing apparatus 100 according to the first embodiment, the irradiation amount D (dose) of each pixel 36 (irradiation position) on the sample surface irradiated with the multiple photoelectron beams 20 is controlled in (N·(n−1)+1) gradations, including zero. In this way, by performing multiple writing, the gradation control steps of each beam can be made coarse.

[0066] As a control gradation value calculation process, the control circuit 81 in the photoelectron source control circuit 131 calculates, for each shot, a gradation value obtained by gradating the intensity of the laser light output from the light source 15 required to output the beam current of each pixel irradiated in that shot.

[0067] Then, the control circuit 81 controls each amplifier 80 so that, for each shot, an amplifier 80 output corresponding to the calculated gradation value is obtained during the common irradiation time Ttr. The multiple amplifiers 80 control the multiple light sources 15 so that each light source 15 individually outputs a light intensity corresponding to a multiple gradation that defines the irradiation amount (dose) (here, the beam current corresponding to the irradiation amount). Specifically, the multiple amplifiers 80 control the multiple light sources 15 so that each light source 15 individually outputs a light intensity corresponding to a gradation value obtained by gradating the intensity of the laser light output from the light source 15 necessary to output the beam current for each pixel to be irradiated in the shot. As a result, during the common irradiation time Ttr, laser light corresponding to the output from each amplifier 80 is output from the corresponding light source 15.

[0068] During the common irradiation time Ttr, each electron source 42 is irradiated with the laser light and emits a photoelectron beam of the corresponding beam current.

[0069] The writing mechanism 150 writes a pattern on the sample 101 using multiple photoelectron beams 20, each of which has its individual beam current maintained constant during the shot period. Also, during the shot period of the common irradiation time Ttr, the individual beam current of each photoelectron beam is maintained constant. This prevents the occurrence of a beam that is turned off midway. At this time, as described above, tracking control is performed so that the irradiation area 34 of the beam array constituting the multi-photoelectron beam follows the movement of the XY stage 105. Then, multiple shots are performed by shifting the pixel 36 (irradiation position) during each tracking operation. In the example of FIG. 7 , the sub-deflector 209 sequentially shifts the irradiation position (pixel 36) during each tracking operation, and the multi-photoelectron beam 20 is fired, for example, four times in a shot cycle Ttr, to write (expose) four different pixels 36 in the same sub-irradiation area 29 with the same beam. At this time, the writing control unit 72 controls the writing operation so that multiple shots are performed in a sorted order for each tracking operation. In the example of FIG. 7 , the first shot irradiates the pixel in the first row from the bottom. The second shot irradiates the pixel in the third row from the bottom. The third shot irradiates the pixel in the second row from the bottom. The fourth shot irradiates the pixel in the fourth row from the bottom. In the second tracking operation after the tracking reset, for example, the first shot irradiates the pixels in the first row from the bottom. The sorting order changes for each tracking operation.

[0070] Furthermore, the correction lens 214 corrects the focal position of the multi-photoelectron beams 20 for each shot. Here, the correction lens 214 corrects the focal position shift caused by the Coulomb effect according to the total current of the multi-photoelectron beams 20. In the first embodiment, since the current of the multi-photoelectron beams 20 does not change during the shot period, the correction lens 214 can perform correction under the same control state during the shot. Note that when the focus is corrected by the correction lens 214, the imaging magnification and the rotation angle of the image generally change. If it is necessary to suppress changes in the imaging magnification and the rotation angle of the image, it is sufficient to use an electron optical system in which the correction lens is a combination of multiple lenses, for example, so that the magnification and rotation during focus correction are sufficiently small. Furthermore, by performing the sorting process, the total current changes in one direction, and therefore the voltage required to correct the focal position can also be changed in one direction. This makes it easier to control the correction voltage with higher precision than when the correction voltage fluctuates back and forth.

[0071] 10 is a cross-sectional view showing an example of the configuration of a part of an electron source array in a modified example of Embodiment 1. In FIG. FIG. 11 is a top view showing an example of the configuration of a part of the electron source array in the modified example of the first embodiment. In the modified examples shown in FIGS. 10 and 11 , the electron source array 40 receives multiple laser beams to emit multiple photoelectron beams 20. However, in the modified example, each electron source 42 of the electron source array 40 is arranged to receive laser beams from, for example, two or more optical fibers 18 serving as light sources 15. The modified examples shown in FIGS. 10 and 11 illustrate a case in which laser beams are received from four light sources 15 per electron source 42. Four optical fibers 18 are arranged per electron source 42 in the light source array 14. The laser beams emitted from each optical fiber 18 are reduced in the focusing direction by the corresponding lens in the lens array 16, reflected by the extraction electrode 47, and directed toward the electron source 42. The extraction electrode 47 functions as a mirror in addition to its function as an extraction electrode. In the example shown in FIG. 10 , the surface of the extraction electrode 47 is formed, for example, in a spherical concave shape.

[0072] In a modification of the first embodiment, the value of the beam current of each photoelectron beam of the multi-photoelectron beam 20 is controlled by the number of laser beams received by the corresponding electron source 42. In the modification of FIGS. 10 and 11, for example, by combining four light sources 15, it is possible to control it in five gradations including zero. When performing multiple drawing with N=8, it is possible to control it in 33 (=8×(5−1)+1) gradations. Here, since the intensity of the laser beams received by the electron source 42 is controlled by the number of laser beams, the intensity of each laser beam may be the same.

[0073] As described above, the output power of the laser beam from each light source may be variably controlled. By combining variably controlling the output power of the laser beam from each light source and controlling the number of laser beams in this manner, the resolution of the beam current control can be further improved.

[0074] Fig. 12 is a diagram showing an example of a photoelectron source control circuit in a modified example of the first embodiment. In Fig. 12, a control circuit 81 and a plurality of switch circuits 82 are arranged in a photoelectron source control circuit 131. The number of switch circuits 82 arranged is equal to or greater than the number of electron sources 42. The plurality of switch circuits 82 controlled by the control circuit 81 individually switch the number of light sources 15 (optical fibers 18) that output light to the corresponding electron source 42 so that each electron source 42 individually receives laser light in a number corresponding to a plurality of gradations that define the irradiation amount (dose amount). Other details are the same as those in Fig. 2 or 3.

[0075] As described above, according to the first embodiment, it is possible to eliminate changes in the number of ON beams during a shot period, thereby suppressing changes in the influence of the Coulomb effect during a shot period.

[0076] Embodiment 2 In the first embodiment, a configuration has been described in which the shape of each beam of the multi photoelectron beam 20 emitted from the multi electron source 10 is used as is. In the second embodiment, a configuration will be described in which the multi photoelectron beam 20 emitted from the multi electron source 10 is reshaped. Points that are not particularly explained below are the same as those in the first embodiment.

[0077] 13 is a conceptual diagram showing the configuration of a drawing apparatus in embodiment 2. In FIG. 13, the configuration is the same as in FIG. 1 except that a shaping aperture array substrate 203 is arranged downstream of a multi-photoelectron source mechanism 201.

[0078] FIG. 14 is a conceptual diagram showing the configuration of a shaping aperture array substrate in the second embodiment. In FIG. 14 , holes (openings) 22 are formed in a matrix of p columns by q columns (p, q≧2) in the x and y directions at a predetermined arrangement pitch in the shaping aperture array substrate 203. In FIG. 14 , for example, 512 columns by 512 columns of holes 22 are formed in the x and y directions. The multiple holes 22 are formed to match the trajectories of the multiple photoelectron beams 20 emitted from the multi-photoelectron source 10 (multi-photoelectron source mechanism 201). The photoelectron beams emitted from the multi-photoelectron source 10 do not necessarily have a uniform shape and size. Therefore, the shaping aperture array substrate 203 shapes the multiple photoelectron beams emitted from the multi-photoelectron source 10. Specifically, the shape and size of each photoelectron beam are shaped. Specifically, portions of the emitted multi-photoelectron beams 20 pass through the multiple holes 22, thereby shaping the multi-photoelectron beams 20 into a desired shape and size. Then, the sample 101 is irradiated with the shaped multi-photoelectron beams 20 .

[0079] As described above, according to the second embodiment, the multiple photoelectron beams 20 can be shaped into a desired shape and size, and therefore the sample 101 can be written with the multiple photoelectron beams 20 of uniform shape and size.

[0080] Embodiment 3 In the second embodiment, a configuration for shaping the multiple photoelectron beams 20 into a preset unique size has been described, but in the third embodiment, a configuration for shaping the multiple photoelectron beams 20 into a plurality of sizes will be described. Points that are not particularly explained below are the same as those in the first or second embodiment.

[0081] Fig. 15 is a conceptual diagram showing the configuration of a drawing device in embodiment 3. Fig. 15 is the same as Fig. 1 except that a shaping aperture array substrate 203, a driving circuit 212, an aperture control circuit 133, and a selection unit 56 are arranged downstream of a multi-photoelectron source mechanism 201.

[0082] Each of the "~ units" such as the data processing unit 50, the current amount calculation unit 52, the sorting unit 54, the selection unit 56, the drawing control unit 72, and the transfer processing unit 74 has a processing circuit. Such a processing circuit includes, for example, an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device. Each of the "~ units" may use a common processing circuit (the same processing circuit) or different processing circuits (separate processing circuits). Information input to and output from the data processing unit 50, the current amount calculation unit 52, the sorting unit 54, the selection unit 56, the drawing control unit 72, and the transfer processing unit 74, as well as information being calculated, is stored in the memory 112 each time.

[0083] 16 is a conceptual diagram showing the configuration of a shaping aperture array substrate in the third embodiment. In FIG. 16, holes (openings) 22-1 are formed in a matrix of p columns by q columns (p, q≧2) in the x and y directions at a predetermined arrangement pitch in the shaping aperture array substrate 203. Furthermore, holes (openings) 22-2 are formed in a matrix of p columns by q columns (p, q≧2) that are different in size from the holes 22-1 and are formed at the same arrangement pitch as the holes 22-1, with their positions shifted. In FIG. 16, holes 22-2 are formed so as to be positioned between adjacent holes 22-1 of the plurality of holes 22-1 but not to overlap. For example, the plurality of holes 22-1 and the plurality of holes 22-2 are formed in a positional relationship in which they are shifted by, for example, ½ of the arrangement pitch in the x and y directions.

[0084] The selection unit 56 selects the beam size. Then, information about the selected beam size is output from the selection unit 56 to the aperture control circuit 133. The aperture control circuit 133 controls the drive circuit 212, which moves the shaping aperture array substrate 203 within the plane. This makes it possible to selectively align one of the multiple holes 22-1 and the multiple holes 22-2 on the trajectory of the multi-photoelectron beam 20. This makes it possible to change the size of the shaped multi-photoelectron beam 20. For example, the size of each beam can be selectively changed depending on the required drawing accuracy.

[0085] Although the embodiments have been described above with reference to specific examples, the present invention is not limited to these specific examples.

[0086] Although the description of the device configuration, control method, and other parts not directly necessary for the explanation of the present invention have been omitted, the required device configuration and control method can be appropriately selected and used. For example, the description of the control unit configuration that controls the drawing device 100 has been omitted, but it goes without saying that the required control unit configuration can be appropriately selected and used.

[0087] In addition, all electron beam writing apparatuses and electron beam writing methods that include the elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention. [Explanation of symbols]

[0088] 10 Multi-photoelectron source 11 Laser light 12 electrodes 13 PCB 14 Light source array 15 light source 16 Lens Array 18 Optical Fiber 20 Multi-photoelectron beam 22 holes 27 Control Grid 28 pixels 29 Sub-irradiation area 30 drawing area 32 stripe area 34 Irradiation area 36 pixels 40 Electron Source Array 41 Glass substrate 42 Electron source 43 Light-shielding film 44 Extraction electrode 45 Outer wall 46 Angle-Limiting Aperture Array 50 Data Processing Unit 52 Current amount calculation section 54 Sorting processing section 72 Drawing control unit 74 Transfer Processing Unit 80 Amps 81 Control circuit 82 Switch Circuit 100 Drawing device 101 Sample 106 Case 110 Control computer 112 memory 130 Deflection control circuit 131 Photoelectron source control circuit 132,134 DAC amplifier unit 133 Aperture control circuit 136 Lens control circuit 137 Acceleration electrode control circuit 138 Stage control circuit 139 Stage Position Measuring Instrument 140,142 Storage device 150 Drawing mechanism 160 Control circuit 201 Multi-Photoelectron Source Mechanism 203 Shaped Aperture Array Substrate 205 Electromagnetic Lens 206 Limiting Aperture Substrate 207 Electromagnetic Lens 208 Deflector 209 Deflector 210 Mirror 212 Drive circuit 213 Deflector 214 Corrective Lenses

Claims

1. a multi-photoelectron source that emits multiple photoelectron beams; a control circuit that controls the multi-photoelectron source so that, for each shot of the multi-photoelectron beam, all photoelectron beams that become ON beams among the multi-photoelectron beams in that shot have a common irradiation time, and individual beam currents of the photoelectron beams are maintained constant during the shot period; a writing mechanism for writing a pattern on a sample using the multiple photoelectron beams, each of which has an individual beam current maintained constant during a shot period; A multi-electron beam lithography device comprising:

2. The multi-photoelectron source comprises: A plurality of light sources outputting a plurality of lights; an electron source array that receives the plurality of light beams and thereby emits the multi-photoelectron beams; and a value of a beam current of each photoelectron beam of the multiple photoelectron beams is controlled by an intensity of light received by a corresponding electron source of the electron source array; 2. The multi-electron beam writing apparatus according to claim 1, wherein the control circuit has a plurality of amplifiers that control the plurality of light sources so that each light source individually outputs a light intensity corresponding to a plurality of gradations that define a dose amount.

3. The multi-photoelectron source comprises: A plurality of light sources outputting a plurality of lights; an electron source array that receives the plurality of light beams and thereby emits the multi-photoelectron beams; and each electron source of the electron source array is arranged to be able to receive light from two or more light sources; a value of a beam current of each photoelectron beam of the multi-photoelectron beams is controlled by the number of lights received by a corresponding electron source of the electron source array; 2. The multi-electron beam lithography device according to claim 1, wherein the control circuit has a plurality of switch circuits that individually switch the number of light sources that output light to the corresponding electron source so that each electron source individually receives a number of lights corresponding to a plurality of gradations that define the dose.

4. 4. The multi-electron beam drawing apparatus according to claim 1, wherein the electron optical system has a correction lens for correcting the focal position of the multi-photoelectron beams for each shot.

5. The sample is multiply imaged with a multiplicity N, The intensity of the light received by each electron source is controlled in n gradations, including zero.

4. A multi-electron beam lithography device according to claim 2, wherein the dose at each irradiation position on the sample surface irradiated with the multi-photoelectron beam is controlled in (N·(n−1)+1) gradations, including zero.

6. The sample is placed on a movable stage; a tracking control is performed so that the irradiation area of ​​the beam array constituting the multi-photoelectron beam follows the movement of the stage; During each tracking operation, multiple shots are performed with the irradiation position shifted, a sorting processing unit that sorts, for each tracking operation, the total beam current of each of the plurality of shots performed during the tracking operation in descending or ascending order; a drawing control unit that controls a drawing operation so that the plurality of shots are performed in the sorted order for each tracking operation; 4. The multi-electron beam drawing apparatus according to claim 1, further comprising:

7. a shaping aperture array substrate for shaping the multi-photoelectron beams emitted from the multi-photoelectron source; 4. The multi-electron beam lithography apparatus according to claim 1, wherein the sample is irradiated with shaped multi-photoelectron beams.

8. emitting multiple photoelectron beams from a multiple photoelectron source; controlling the multi-photoelectron source so that, for each shot of the multi-photoelectron beam, all photoelectron beams that become ON beams among the multi-photoelectron beams in that shot have a common irradiation time and individual beam currents of the photoelectron beams are maintained constant during the shot; writing a pattern on a specimen using the multiple photoelectron beams, each with an individual beam current maintained constant during a shot; A multi-electron beam writing method comprising:

Images