Charged Particle Beam Image Acquisition Device and Charged Particle Beam Image Acquisition Method

Abstract

To provide a device which can perform scanning in which an ending point of preceding scanning and a starting point of subsequent scanning are at positions apart from each other with a constant distance or longer when acquiring an image by using a multi-beam.SOLUTION: A charged particle beam image acquisition device comprises: a primary electronic optical system 151 which irradiates a substrate with a multi-beam formed of a plurality of M (M is an integer equal to or greater than 2) charged particle beams arrayed with the same pitch p on a substrate surface in the first direction; a main deflector 208 which deflects the multi-beam collectively to a block region group out of a plurality of block regions divided in a size with which p / N (N is an integer equal to or greater than 3) inspection regions of the substrate can be obtained in the first direction and in a prescribed size in the second direction orthogonal to the first direction and deflects the multi-beam to the new block region group every time scanning of the block region group is terminated; and a sub deflector 209 which collectively deflects the multi-beam so as to scan the block region group. N and M are prime to each other, and M-1 is not the multiple of N.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a charged particle beam image acquisition device and a charged particle beam image acquisition method. For example, it relates to a device and method for acquiring a secondary electron image of a pattern emitted by irradiating a multi-beam with an electron beam.

Background Art

[0002] In recent years, with the increasing integration and large capacity of large-scale integrated circuits (LSIs), the circuit line width required for semiconductor elements has become increasingly narrow. And for the manufacture of LSIs that require a huge manufacturing cost, improvement in yield is essential. However, as represented by 1-gigabit-class DRAMs (random access memories), the patterns constituting LSIs are on the order of submicrons to nanometers. In recent years, with the miniaturization of LSI pattern dimensions formed on semiconductor wafers, the dimensions that must be detected as pattern defects have also become extremely small. Therefore, there is a need for higher precision of pattern inspection devices for inspecting defects in ultra-fine patterns transferred onto semiconductor wafers.

[0003] In an inspection device, for example, a multi-beam using an electron beam is irradiated onto a substrate to be inspected, secondary electrons corresponding to each beam emitted from the substrate to be inspected are detected, and a pattern image is captured. And a method is known in which inspection is performed by comparing the captured measurement image with design data or a measurement image of the same pattern on the substrate. For example, there is "die to die inspection" in which measurement image data of the same pattern at different locations on the same substrate are compared. In addition, there is "die to database inspection" in which design image data (reference image) is generated based on pattern-designed design data and compared with a measurement image that becomes measurement data of the captured pattern. The captured image is sent to a comparison circuit as measurement data. In the comparison circuit, after alignment of the images, the measurement data and the reference data are compared according to an appropriate algorithm. And when they do not match, it is determined that there is a pattern defect.

[0004] In a pattern inspection apparatus using such multi-beams, secondary electrons are detected by scanning each small area of a substrate to be inspected. At this time, by using multi-beams arranged at the same pitch on a straight line, a large number of beams can be arranged within a limited area, so that it becomes possible to simultaneously scan a large number of small areas at once.

[0005] However, when scanning is performed with multi-beams while the stage is continuously moving, small areas for which pattern images have already been acquired by other beams arranged in the moving direction are successively sent. Therefore, useless scanning is repeated for small areas for which pattern images have already been acquired. To avoid this, the inspection area is divided into a plurality of small areas arranged at a width obtained by dividing the beam pitch by the number of divisions in the stage moving direction. Then, a group of small areas arranged in the number of beam pitches in the stage moving direction is scanned with multi-beams. Next, a new group of small areas arranged in the number of beam pitches separated by the number of beams in the reverse direction of the stage moving direction is scanned with multi-beams. And such an operation is repeated. If the combination of the value of the number of beams and the value of the number of divisions results in the greatest common divisor being 1, the entire area can be scanned without repeating useless scanning (see, for example, Patent Document 1).

[0006] Here, each irradiation area irradiated with a beam will be charged, although there are differences in degree. When scanning is performed so that the ends of adjacent areas overlap to prevent image dropout, the charge amount in the overlapping part increases. When scanning the charged position or its vicinity, the obtained image will include the influence of charging.

[0007] However, in the method described above, although useless scanning is no longer repeated, there may be a case where the end point of the previous scan and the start point of the next scan are in extremely close positions. In such a case, the data obtained in the next scan is affected by the charging due to the previous scan. Therefore, a scanning method for reducing the influence of charging is required.

Prior Art Documents

Patent Documents

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-017571 [Summary of the Invention] [Problems to be Solved by the Invention]

[0009] Therefore, one aspect of the present invention provides an apparatus and a method capable of performing a scan in which the end point of the immediately preceding scan and the start point of the next scan are separated by a certain distance or more when acquiring an image using a multi-beam. [Means for Solving the Problems]

[0010] A charged particle beam image acquisition apparatus according to one aspect of the present invention includes: a movable stage on which a substrate to be inspected is placed; an illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface, where M (M is an integer of 2 or more); among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained at p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, a first deflector that collectively deflects the multi-beam onto a group of block regions on the substrate arranged in M in the first direction at a pitch p, and collectively deflects the multi-beam onto a new group of block regions arranged in M in the first direction at a pitch p and separated by M in the first direction each time the scanning of the group of block regions is completed; a second deflector that collectively deflects the multi-beam so as to scan the group of block regions; a detector that detects secondary electrons emitted from the substrate due to irradiation of the substrate with the multi-beam; and is provided with N and M are relatively prime to each other, and M - 1 is not a multiple of N, and the group of block regions arranged continuously in the first direction and the second ofA group of blocks arranged continuously in a first direction adjacent to a direction is arranged such that their positions are shifted from each other in a size smaller than the width of the block region in the first direction in the first direction.

[0011] The charged particle beam image acquisition device according to another aspect of the present invention is A movable stage on which a substrate to be inspected is placed, An illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface in the first direction, where M (M is an integer of 2 or more) charged particle beams are arranged. Among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, the multi-beam is collectively deflected to a group of block regions on the substrate arranged in M in the first direction at a pitch p in the first direction, and every time the scanning of the group of block regions is completed, the multi-beam is collectively deflected to a new group of block regions arranged in M in the first direction at a pitch p in the first direction and separated by M in the first direction. A first deflector; A second deflector that collectively deflects the multi-beam so as to scan the group of block regions; A detector that detects secondary electrons emitted from the substrate due to irradiation of the substrate with the multi-beam; Comprising N and M are relatively prime to each other, and M - 1 is not a multiple of N. The beams adjacent to each other in the second direction of the multi-beam are arranged such that their positions are shifted by S block regions (S is an integer of 1 or more) relative to each other in the first direction. It is characterized in that |M - |S| - 1| is not a multiple of N or 0, and S is not a multiple of N.

[0012] The charged particle beam image acquisition device according to another aspect of the present invention is A movable stage on which a substrate to be inspected is placed, An illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface in the first direction, where M (M is an integer of 2 or more) charged particle beams are arranged. Among a plurality of block regions obtained by dividing an inspection region of a substrate into a size obtained by p / N (N is an integer of 3 or more) in a first direction and a predetermined size in a second direction orthogonal to the first direction, a multi-beam is collectively deflected to a group of block regions on the substrate arranged in M in a pitch p in the first direction, and every time the scanning of the group of block regions is completed, the multi-beam is collectively deflected to a new group of block regions arranged in M in a pitch p in the first direction and separated by M in the first direction; a first deflector; A second deflector that collectively deflects the multi-beam so as to scan the group of block regions; A detector that detects secondary electrons emitted from the substrate due to irradiation of the substrate with the multi-beam; Comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N; The plurality of block regions are formed in a size such that two or more block regions are arranged within a beam pitch in the second direction.

[0013] A method for acquiring a charged particle beam image according to an aspect of the present invention includes: Using a multi-beam composed of a plurality of charged particle beams arranged in M (M is an integer of 2 or more) at the same pitch p on the substrate surface in a first direction, among a plurality of block regions obtained by dividing an inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, a step of scanning a group of block regions on the substrate arranged in M in a pitch p in the first direction; Every time the scanning of a group of block regions arranged in M in a pitch p is completed, a step of collectively deflecting the multi-beam to a new group of block regions arranged in M in a pitch p and separated by M in the first direction; Every time the scanning of a group of block regions continuously arranged in the first direction is completed, a step of collectively deflecting the multi-beam to a new group of block regions arranged in M in an adjacent pitch p in the second direction; A step of detecting secondary electrons emitted from the substrate due to irradiation of the substrate with the multi-beam; Comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N. A group of block regions arranged continuously in the first direction and a group of blocks arranged continuously in the first direction adjacent to the second direction are arranged with their positions shifted from each other in a size smaller than the width of the block region in the first direction in the first direction.

[0014] Another method for acquiring a charged particle beam image according to an aspect of the present invention is Using a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on a substrate surface (M is an integer of 2 or more), among a plurality of block regions obtained by dividing an inspection region of the substrate into a size obtained at p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, scanning a group of block regions on the substrate arranged in M in the first direction at the pitch p; Each time the scanning of the group of block regions arranged in M at the pitch p is completed, collectively deflecting the multi-beam to a new group of block regions arranged in M in the first direction and separated by M in the first direction and arranged in M at the pitch p in the first direction; Detecting secondary electrons emitted from the substrate due to irradiating the substrate with the multi-beam; Comprising N and M are relatively prime to each other, and M - 1 is not a multiple of N; Beams adjacent to each other in the second direction of the multi-beam are arranged with their positions shifted by S block regions (S is an integer of 1 or more) relative to each other in the first direction. It is preferable that |M - |S| - 1| is not a multiple of N or 0, and S is not a multiple of N.

[0015] Another method for acquiring a charged particle beam image according to an aspect of the present invention is Using a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p on the substrate surface in the first direction, where M (M is an integer of 2 or more) are arranged, among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained at p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, a step of scanning a block region group on the substrate where M are arranged at a pitch p in the first direction; Each time the scanning of the block region group where M are arranged at a pitch p is completed, a step of collectively deflecting the multi-beam to a new block region group where M are arranged at a pitch p in the first direction and are separated by M in the first direction; A step of detecting secondary electrons emitted from the substrate due to irradiating the substrate with the multi-beam; Comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N; The plurality of block regions are formed in a size such that two or more block regions are arranged within the beam-to-beam pitch in the second direction.

Advantages of the Invention

[0016] According to one aspect of the present invention, when acquiring an image using a multi-beam, it is possible to perform scanning such that the end point of the immediately preceding scan and the start point of the next scan are at positions separated by a certain distance or more. Therefore, the influence of charging can be reduced.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Mode for carrying out the invention

[0018] Hereinafter, in the embodiment, as an example of an image acquisition apparatus, an inspection apparatus will be described. However, it is not limited to this. Any other apparatus may be used as long as it is an apparatus that acquires an image using a charged particle beam. Further, as an example of the charged particle beam, the case of using an electron beam will be described. However, it is not limited to this. Other charged particle beams such as an ion beam may be used.

[0019] Embodiment 1. FIG. 1 is a configuration diagram showing the configuration of the pattern inspection apparatus in Embodiment 1. In FIG. 1, an inspection apparatus 100 for inspecting a pattern formed on a substrate is an example of a multi-electron beam inspection apparatus. The inspection apparatus 100 includes an image acquisition mechanism 150 and a control system circuit 160 (control unit). The image acquisition mechanism 150 includes an electron beam column 102 (electron lens barrel), an inspection chamber 103, a detection circuit 106, a chip pattern memory 123, a stage drive mechanism 142, and a laser length measurement system 122. In the electron beam column 102, an electron gun 201, an illumination lens 202, a shaping aperture array substrate 203, an electromagnetic lens 205, a batch deflector 212, a limiting aperture substrate 213, an electromagnetic lens 206, an electromagnetic lens 207 (objective lens), a main deflector 208, a sub deflector 209, an E×B separator (beam separator) 214, a deflector 218, an electromagnetic lens 224, a deflector 226, and a multi-detector 222 are arranged.

[0020] The electron gun 201, the electromagnetic lens 202, the shaping aperture array substrate 203, the electromagnetic lens 205, the batch deflector 212, the limiting aperture substrate 213, the electromagnetic lens 206, the electromagnetic lens 207 (objective lens), the main deflector 208, and the sub deflector 209 constitute a primary electron optical system 151 (illumination optical system). Further, the deflector 218, the electromagnetic lens 224, and the deflector 226 constitute a secondary electron optical system 152 (detection optical system).

[0021] Inside the inspection chamber 103, at least a stage 105 movable in the XY directions is arranged. On the stage 105, a substrate 101 (sample) to be inspected is arranged. The substrate 101 includes an exposure mask substrate and a semiconductor substrate such as a silicon wafer. When the substrate 101 is a semiconductor substrate, a plurality of chip patterns (wafer dice) are formed on the semiconductor substrate. When the substrate 101 is an exposure mask substrate, a chip pattern is formed on the exposure mask substrate. The chip pattern is composed of a plurality of graphic patterns. By exposing and transferring the chip pattern formed on such an exposure mask substrate onto the semiconductor substrate a plurality of times, a plurality of chip patterns (wafer dice) are formed on the semiconductor substrate. Hereinafter, the case where the substrate 101 is a semiconductor substrate will be mainly described. The substrate 101 is arranged on the stage 105 with the pattern formation surface facing upward, for example. Also, on the stage 105, a mirror 216 that reflects laser light for laser length measurement irradiated from a laser length measurement system 122 arranged outside the inspection chamber 103 is arranged.

[0022] Also, the multi-detector 222 is connected to the detection circuit 106 outside the electron beam column 102. The detection circuit 106 is connected to the chip pattern memory 123.

[0023] In the control system circuit 160, a control computer 110 that controls the entire inspection apparatus 100 is connected via a bus 120 to a position circuit 107, a comparison circuit 108, a reference image creation circuit 112, a stage control circuit 114, a lens control circuit 124, a blanking control circuit 126, a deflection control circuit 128, an E×B control circuit 132, a storage device 109 such as a magnetic disk device, a monitor 117, a memory 118, and a printer 119. Also, the deflection control circuit 128 is connected to DAC (digital-analog conversion) amplifiers 144, 146, 148. The DAC amplifier 146 is connected to the main deflector 208, the DAC amplifier 144 is connected to the sub-deflector 209, and the DAC amplifier 148 is connected to the deflector 218.

[0024] Further, the chip pattern memory 123 is connected to the comparison circuit 108. Also, the stage 105 is driven by a drive mechanism 142 under the control of the stage control circuit 114. In the drive mechanism 142, for example, a drive system such as a three-axis (X-Y-θ) motor that drives in the X direction, Y direction, and θ direction in the stage coordinate system is configured, and the stage 105 can move in the XYθ directions. These X motor, Y motor, and θ motor (not shown) can use, for example, a stepper motor. The stage 105 can move in the horizontal direction and the rotational direction by the motors of each of the XYθ axes. And the moving position of the stage 105 is measured by the laser length measurement system 122 and supplied to the position circuit 107. The laser length measurement system 122 measures the position of the stage 105 based on the principle of laser interferometry by receiving the reflected light from the mirror 216. The stage coordinate system is set, for example, with the X direction, Y direction, and θ direction of the primary coordinate system with respect to a plane orthogonal to the orbit central axis (optical axis) of the multi-primary electron beam 20.

[0025] The electromagnetic lens 202, electromagnetic lens 205, electromagnetic lens 206, electromagnetic lens 207, and electromagnetic lens 224 are controlled by the lens control circuit 124. The E×B separator 214 is controlled by the E×B control circuit 132. Also, the batch deflector 212 is an electrostatic deflector composed of two or more electrodes, and is controlled by the blanking control circuit 126 via a DAC amplifier (not shown) for each electrode. The sub-deflector 209 is an electrostatic deflector composed of four or more electrodes, and is controlled by the deflection control circuit 128 via the DAC amplifier 144 for each electrode. The main deflector 208 is an electrostatic deflector composed of four or more electrodes, and is controlled by the deflection control circuit 128 via the DAC amplifier 146 for each electrode. The deflector 218 is an electrostatic deflector composed of four or more electrodes, and is controlled by the deflection control circuit 128 via the DAC amplifier 148 for each electrode. Also, the deflector 226 is an electrostatic deflector composed of four or more electrodes, and is controlled by the deflection control circuit 128 via a DAC amplifier (not shown) for each electrode.

[0026] A high-voltage power supply circuit (not shown) is connected to the electron gun 201. With the application of an acceleration voltage from the high-voltage power supply circuit between a filament (not shown) and an extraction electrode in the electron gun 201, along with the application of a voltage to a predetermined extraction electrode (Wehnelt) and the heating of a cathode at a predetermined temperature, an electron group emitted from the cathode is accelerated and emitted as an electron beam 200.

[0027] Here, in FIG. 1, the configurations necessary for explaining Embodiment 1 are described. For the inspection apparatus 100, it may usually have other necessary configurations.

[0028] FIG. 2 is a conceptual diagram showing the configuration of the shaping aperture array substrate in Embodiment 1. In FIG. 2, on the shaping aperture array substrate 203, holes (openings) 22 in a two-dimensional (matrix) form of M columns in the horizontal (x direction) × M' rows in the vertical (y direction) (M is an integer of 2 or more, M' is an integer of 1 or more) are formed at a predetermined array pitch L in the x direction and a predetermined array pitch L' in the y direction. When the reduction magnification of the multi-beam is a times (when irradiating the substrate 101 after reducing the multi-beam diameter to 1 / a), and the beam pitch between the multi-beams in the x direction on the substrate 101 is p and the beam pitch between the multi-beams in the y direction is p', the array pitch L has a relationship of L = (a × p), L' = (a × p'). The example in FIG. 2 shows the case where 5 × 5 holes 22 for forming multi-beams with M = 5 and M' = 5 are formed. L may be equal to L', or L and L' may have different values.

[0029] The image acquisition mechanism 150 acquires a test image of the graphic pattern from the substrate 101 on which the graphic pattern is formed, using a multi-beam by an electron beam. Hereinafter, the operation of the image acquisition mechanism 150 in the inspection apparatus 100 will be described.

[0030] The electron beam 200 emitted from the electron gun 201 (emission source) is refracted by the electromagnetic lens 202 and illuminates the entire shaped aperture array substrate 203. As shown in FIG. 2, a plurality of holes 22 (openings) are formed in the shaped aperture array substrate 203, and the electron beam 200 illuminates the region including all the plurality of holes 22. Each part of the electron beam 200 irradiated at the positions of the plurality of holes 22 passes through the plurality of holes 22 of the shaped aperture array substrate 203 respectively, thereby forming the multi-primary electron beam 20.

[0031] The formed multi-primary electron beam 20 is refracted by the electromagnetic lens 205 and the electromagnetic lens 206 respectively, and while repeating the intermediate image and the crossover, it passes through the E×B separator 214 arranged at the intermediate image plane (image plane conjugate position) of each beam of the multi-primary electron beam 20 and proceeds to the electromagnetic lens 207. Further, by arranging the limiting aperture substrate 213 with restricted through holes near the crossover position of the multi-primary electron beam 20, the scattered beam can be shielded. Also, the entire multi-primary electron beam 20 can be blanked by collectively deflecting the entire multi-primary electron beam 20 by the batch deflector 212 and shielding the entire multi-primary electron beam 20 with the limiting aperture substrate 213.

[0032] When the multi-primary electron beam 20 enters the electromagnetic lens 207 (objective lens), the electromagnetic lens 207 focuses (images) the multi-primary electron beam 20 onto the substrate 101. In other words, the electromagnetic lens 207 irradiates the substrate 101 with the multi-primary electron beam 20. The multi-primary electron beam 20 focused (focused) on the substrate 101 (sample) surface by the objective lens 207 is collectively deflected by the main deflector 208 and the sub-deflector 209 and irradiated to the respective irradiation positions of each beam on the substrate 101. Thus, the primary electron optical system 151 irradiates the substrate 101 surface with the multi-primary electron beam.

[0033] When the multi-primary electron beam 20 is irradiated onto a desired position of the substrate 101, a bundle of secondary electrons including reflected electrons (multi-secondary electron beam 300) corresponding to each beam of the multi-primary electron beam 20 is emitted from the substrate 101 due to the irradiation of the multi-primary electron beam 20.

[0034] The multi-secondary electron beam 300 emitted from the substrate 101 travels through the electromagnetic lens 207 and proceeds to the E×B separator 214.

[0035] FIG. 3 is a configuration diagram showing an example of the E×B separator in Embodiment 1. In FIG. 3, the E×B separator 214 has a plurality of magnetic poles of two or more poles using coils and a plurality of electrodes of two or more poles. In the example of FIG. 3, an example of an E×B separator having four-pole magnetic poles 17 (electromagnetic deflection coils) with phases shifted by 90° each and four-pole electrodes 18 (electrostatic deflection electrodes) with phases also shifted by 90° each is shown. Then, for example, by setting two opposing magnetic poles as the N pole and the S pole, a directional magnetic field is generated by such a plurality of magnetic poles. Similarly, for example, by applying voltages V with opposite signs to two opposing electrodes, a directional electric field is generated by such a plurality of electrodes. Specifically, the E×B separator 214 generates an electric field and a magnetic field in a direction perpendicular to each other on a plane perpendicular to the direction (orbital central axis) in which the central beam of the multi-primary electron beam 20 travels. The electric field exerts a force in the same direction regardless of the traveling direction of the electrons. In contrast, the magnetic field exerts a force according to Fleming's left-hand rule. Therefore, the direction of the force acting on the electrons can be changed depending on the intrusion direction of the electrons. For the multi-primary electron beam 20 that intrudes into the E×B separator 214 from above, the force due to the electric field and the force due to the magnetic field cancel each other out, and the multi-primary electron beam 20 travels straight downward. In contrast, for the multi-secondary electron beam 300 that intrudes into the E×B separator 214 from below, both the force due to the electric field and the force due to the magnetic field act in the same direction, and the multi-secondary electron beam 300 is bent obliquely upward and separated from the orbit of the multi-primary electron beam 20. By adjusting the current flowing through the four magnetic poles 17 and the voltage applied to the four electrodes 18, the directions and magnitudes of the electric field and the magnetic field can be adjusted. Therefore, by adjusting the current flowing through the four magnetic poles 17 and the voltage applied to the four electrodes 18, the directions and magnitudes of the force due to the electric field and the force due to the magnetic field can be adjusted.

[0036] The multi-secondary electron beam 300 that is bent obliquely upward and separated from the multi-primary electron beam 20 is guided to the multi-detector 222 by the secondary electron optical system 152. Specifically, the multi-secondary electron beam 300 separated from the multi-primary electron beam 20 is further bent by being deflected by the deflector 218, and is projected onto the multi-detector 222 while being refracted in the focusing direction by the electromagnetic lens 224 at a position away from the orbit of the multi-primary electron beam 20. The multi-detector 222 (multi-secondary electron beam detector) detects the refracted and projected multi-secondary electron beam 300. The multi-detector 222 has a plurality of detection elements (for example, a diode-type two-dimensional sensor not shown). Then, each beam of the multi-primary electron beam 20 collides with the detection element corresponding to each secondary electron beam of the multi-secondary electron beam 300 on the detection surface of the multi-detector 222, generates electrons, and generates secondary electron image data for each pixel. The intensity signal (luminance data) detected by the multi-detector 222 is output to the detection circuit 106.

[0037] FIG. 4 is a diagram showing an example of a plurality of chip regions formed on a semiconductor substrate in Embodiment 1. In FIG. 4, a plurality of chips (wafer dice) 332 are formed in a two-dimensional array in an inspection region 330 of a semiconductor substrate (wafer) 101. A mask pattern for one chip formed on an exposure mask substrate is reduced, for example, by a factor of 1 / 4 and transferred by an exposure apparatus (stepper) (not shown). The region of each chip 332 is divided into a plurality of stripe regions 32 with a predetermined width, for example, in the y direction. The scanning operation by the image acquisition mechanism 150 is performed, for example, for each stripe region 32. For example, while moving the stage 105 in the -x direction, the scanning operation of the stripe region 32 is advanced relatively in the x direction. Each stripe region 32 is divided into a plurality of rectangular regions 33 in the longitudinal direction. The movement of the beam to the target rectangular region 33 is performed by batch deflection of the entire multi-primary electron beam 20 by the main deflector 208. For example, it is virtually divided into a plurality of strip-shaped stripe regions 32 having the same width as a natural multiple of the width of the irradiation region 34 that can be irradiated by one irradiation of the entire multi-primary electron beam 20. In the example of FIG. 4, it is virtually divided into a plurality of strip-shaped stripe regions 32 having the same width as the irradiation region 34.

[0038] FIG. 5 is a diagram showing an example of the irradiation region of the multi-beam and the pixels for measurement in the first embodiment. In FIG. 5, each stripe region 32 is divided, for example, into a plurality of mesh regions in a mesh shape with the beam size of the multi-beam. Each such mesh region becomes a pixel 36 for measurement (unit irradiation region). And in the irradiation region 34, a plurality of pixels 28 for measurement (irradiation positions of the beam at the time of one shot) that can be irradiated by irradiation of M×M' multi-primary electron beams 20 at one time are shown. In other words, the pitch p in the x direction and the pitch p' in the y direction between adjacent pixels 28 for measurement become the pitch between the respective beams of the multi-primary electron beam 20 on the substrate 101. In the example of FIG. 5, taking one of the four adjacent pixels 28 for measurement as one of the four corners of a rectangle, a region surrounded by p×p' in the x and y directions starting from the pixel 28 for measurement is divided in the x direction by the number of divisions N (N is an integer of 3 or more), and one sub-irradiation region 29 (small region) is formed in a rectangular region having a size of p / N in the x direction and -p' in the y direction. In the example of FIG. 5, each sub-irradiation region 29 (individual beam scan region) is shown as being composed of 3×9 pixels.

[0039] FIG. 6 is a conceptual diagram for explaining an example of details of the scanning operation in the comparative example of the first embodiment. In the example of FIG. 6, as a comparative example of the first embodiment, among M×M' multi-primary electron beams 20, M multi-beams in one row in the y direction are shown. Here, M = 5 multi-beams arranged in the x direction at the same pitch p are shown. In the comparative example of the first embodiment, each of the M = 5 multi-beams arranged in the x direction at the same pitch p scans all the regions 27 surrounded by p×p' in the x and y directions starting from the measurement pixel 28 of the beam, and then scans the next region 27 surrounded by p×p'. In the comparative example of the first embodiment, the stage speed is controlled so that the XY stage 105 moves by N·p while each beam scans the region surrounded by p×p' (during the period from t = t0' to t1'). At this time, tracking deflection is performed by the main deflector 208 so that each beam can scan the region surrounded by the p×p' by the deflection operation of the sub-deflector 208. Then, at the time (t = t1') when the scanning of the regions 27 surrounded by p×p' arranged continuously in the x direction for M pieces is completed, tracking reset is performed by collectively deflecting the M = 5 multi-beams in the x direction so that the scanning regions do not overlap. By repeating such an operation, the region on the continuously moving stage can be scanned with the multi-beams so that the scanning regions do not overlap. In the example of FIG. 6, it is necessary to deflect the multi-beams by (M - 1)·p (= 4p) in the x direction (or -x direction). When the number of beams M increases, the swing width of such beam deflection becomes extremely large. Therefore, the influence of the aberration of the electron optical system becomes large.

[0040] FIG. 7 is a conceptual diagram for explaining an example of details of the scanning operation in the first embodiment. In the example of FIG. 7, as the first embodiment, among M×M' multi-primary electron beams 20, M multi-beams in one row in the y direction are shown. Here, similar to FIG. 6, M = 5 multi-beams arranged in the x direction at the same pitch p are shown. In the first embodiment, one of the four adjacent measurement pixels 28 is used as one of the four corners of a rectangle, and the region 27 surrounded by p×p' in the x and y directions with this measurement pixel 28 as the starting point is divided in the x direction by the division number N. Therefore, one sub-irradiation region 29 (block region) is formed by a rectangular region with a size of p / N in the x direction and p' in the y direction (predetermined size). In the example of FIG. 7, the case where the division number N = 3 is shown. In the first embodiment, each of the M = 5 multi-beams arranged in the x direction at the same pitch p scans a sub-irradiation region 29 (block region) with a size of p / N in the x direction and p' in the y direction (predetermined size) starting from the measurement pixel 28 of the beam. Then, the case of scanning the next sub-irradiation region 29 separated by M in the x direction is shown.

[0041] In FIG. 7, in the first embodiment, while each beam scans the sub-irradiation area 29 surrounded by (p / N)×p′ by the sub-deflector 208 during the period (the period from t=t0 to t1), in the case of the stage speed, the XY stage 105 moves by p / N·M. At this time, the main deflector 208 performs tracking deflection with the sub-irradiation area 29 as the tracking area 33 so that each beam can scan the sub-irradiation area 29 by the deflection operation of the sub-deflector 208. Then, when the scanning of the sub-irradiation area 29 is completed (t=t1), the tracking reset is performed by the sub-deflector 209. In the tracking reset, the main deflector 208 deflects the M = 5 multi-beams in the x direction to a position separated by M sub-irradiation areas 29 at once so that the scanning areas do not overlap. In the example of FIG. 7, the main deflector 208 deflects the 5 multi-beams to a position separated by 5 sub-irradiation areas 29 at once. At this time, it goes without saying that the deflection position of the sub-deflector 209 is reset from the final pixel 36 in the sub-irradiation area 29 to the first pixel 28. By repeating such operations during the periods of t=t1~t2, t=t2~t3, ···, even when the stage is continuously moved, the multi-beams can scan on the same stripe area 32 so that the scanning areas do not overlap. In the first embodiment, in order to apply such a scanning method, values in which the number of beams M in the x direction and the division number N are relatively prime to each other are used. By setting such conditions, scanning omission (missing teeth) or overlapping scanning can be avoided.

[0042] FIG. 8 is a diagram showing an example of the relationship between the number of beams and the number of divisions in Comparative Example 1 of Embodiment 1. In Comparative Example 1 of FIG. 8, the case where the number of beams M in the x direction is 4 and the number of divisions N is 3 is shown. The number of beams M' in the y direction may be any integer of 1 or more. In the first scan, in each stage in the y direction, four beams scan four sub-irradiation regions 29 with a pitch p. When the first scan is completed, the irradiation position is moved by the main deflector 208 by a distance corresponding to four sub-irradiation regions 29 in the x direction by tracking reset to four new groups of sub-irradiation regions 29 with a pitch p. Then, as the second scan, such new groups of sub-irradiation regions 29 are scanned. When M' is 2 or more, as shown in FIG. 8, the end point of the first scan of the lower sub-irradiation region 29 and the start point of the second scan of the upper sub-irradiation region 29 are close to each other.

[0043] When scanning each sub-irradiation region 29, in order to prevent omission of the end portion of the image, a margin is taken and a range slightly wider than the sub-irradiation region 29 is scanned. Therefore, the vicinity of the start point of the second scan of the upper sub-irradiation region 29 close to the end point of the first scan of the lower sub-irradiation region 29 scans a portion immediately after charging by the first scan. Thus, in a region irradiated with a plurality of beams, more charging occurs than in other regions. When scanning across regions with different charge amounts within the same sub-irradiation region 29, the obtained image data is affected by the step.

[0044] Also, in that case, the last scan line of the first scan becomes the margin region portion. Therefore, the start scan line of the sub-irradiation region 29 to be scanned in the second scan adjacent in the x direction overlaps with the last scan line of the first scan. Or it overlaps with a scan line near the last scan line of the first scan. Therefore, when M' is 1 or more, the start scan line of the second scan scans a portion immediately after charging in the first scan. Thus, in a region irradiated with a plurality of beams, more charging occurs than in other regions. Therefore, the image data obtained by scanning the start scan line of the second scan is affected by the charging in the first scan.

[0045] Therefore, it can be understood that in order to avoid the influence of charging, it is not sufficient that the number of beams M in the x direction and the number of divisions N are relatively prime to each other. In Comparative Example 1 of FIG. 8, M - 1 = N. In order to avoid the influence of charging, in Embodiment 1, in addition to M and N being relatively prime to each other, as a further condition, it is necessary that M - 1 is not a multiple of N.

[0046] FIG. 9 is a diagram showing an example of the relationship between the number of beams and the number of divisions in Embodiment 1. In the example of FIG. 9, the number of beams M in the x direction is 2, and the number of divisions N is 3. In the example of FIG. 9, M and N are relatively prime to each other, and M - 1 is not a multiple of N. The number of beams M' in the y direction may be any integer of 1 or more. In the first scan, in each stage in the y direction, two beams scan two sub-irradiation regions 29 with a pitch p. When the first scan is completed, the irradiation position is moved by the main deflector 208 by tracking reset to two new sub-irradiation region groups 29 with a pitch p that are separated by a distance corresponding to two sub-irradiation regions 29 in the x direction. Then, as the second scan, such new sub-irradiation region groups 29 are scanned. In the example of FIG. 9, since the second sub-irradiation region 29 is at a position one before the first sub-irradiation region 29, the end point of the first scan and the start point of the second scan can be separated by at least the width of the sub-irradiation region 29. Also in the k-th scan after the third scan, the end point of the (k - 1)-th scan and the start point of the k-th scan can be separated by at least the width of the sub-irradiation region 29.

[0047] Therefore, the start scan line of the k-th scan can be made not to scan above the location immediately after charging in the (k - 1)-th scan. Therefore, the image data obtained by scanning the start scan line of the k-th scan can avoid the influence of charging due to the scan of the (k - 1)-th sub-irradiation region 29.

[0048] Also, regarding the y direction, even when the number of beams M' in the y direction is 2 or more, the image data obtained at the start point of the k-th scan of the upper sub-irradiation region 29 can avoid the influence of charging at the end point of the (k - 1)-th scan of the lower sub-irradiation region 29.

[0049] Note that the number M of multi-primary electron beams in the x direction only needs to be 2 or more, but from the perspective of shortening the inspection time, it is preferably 9 or more. Examples in the case of 9 or more will be described below.

[0050] FIG. 10 is a diagram showing another example of the relationship between the number of beams and the number of divisions in Embodiment 1. In FIG. 10, a scanning operation in the case where the number of divisions N = 5 is shown using M = 9 beams in the x direction. Also, in FIG. 10, each time the second and third scans are performed, the stages are shifted respectively. In the example of FIG. 10, M and N are relatively prime to each other, and M - 1 is not a multiple of N. In the first scan, 9 beams scan 9 sub-irradiation regions 29 with a pitch p. When the first scan is completed, the irradiation position is moved by the main deflector 208 by a distance corresponding to 9 sub-irradiation regions 29 in the x direction by tracking reset to 9 new groups of sub-irradiation regions 29 with a pitch p. Then, as the second scan, such new groups of sub-irradiation regions 29 are scanned. In the example of FIG. 10, since the second sub-irradiation region 29 is at a position one before the first sub-irradiation region 29, the start point of the first scan and the start point of the second scan can be separated by at least the width of the sub-irradiation region 29. Also in the k-th scan after the third scan, the start point of the k-th scan and the start point of the (k - 1)-th scan can be separated by at least the width of the sub-irradiation region 29.

[0051] Therefore, the start scan line of the k-th scan can be made not to scan on the location immediately after charging in the (k - 1)-th scan. Therefore, the image data obtained by scanning the start scan line of the k-th scan can avoid the influence of charging by scanning the (k - 1)-th sub-irradiation region 29.

[0052] FIG. 11 is a diagram showing another example of the relationship between the number of beams and the number of divisions in Embodiment 1. In FIG. 11, a scanning operation in the case of N = 5 divisions is shown using M = 12 beams in the x direction. Also, in FIG. 11, each stage is shifted every time the second and third scans are performed. In the example of FIG. 11, M and N are relatively prime to each other, and M - 1 is not a multiple of N. In the first scan, 12 beams scan 9 sub-irradiation regions 29 with a pitch p. When the first scan is completed, the irradiation position is moved by the tracking reset by the main deflector 208 by a distance corresponding to 12 sub-irradiation regions 29 in the x direction to 12 new groups of sub-irradiation regions 29 with a pitch p. Then, as the second scan, such new groups of sub-irradiation regions 29 are scanned. In the example of FIG. 11, since the second sub-irradiation region 29 is at a position two before the first sub-irradiation region 29, the end point of the first scan and the start point of the second scan can be separated by twice the width of the sub-irradiation region 29. Also, in the k-th scan after the third scan, the end point of the (k - 1)-th scan and the start point of the k-th scan can be separated by twice the width of the sub-irradiation region 29.

[0053] Therefore, the start scanning line of the k-th scan can be made not to scan on the location immediately after charging in the (k - 1)-th scan. Therefore, the image data obtained by scanning the start scanning line of the k-th scan can avoid the influence of charging by scanning the (k - 1)-th sub-irradiation region 29.

[0054] FIG. 12 is a diagram for explaining Comparative Example 2 of Embodiment 1. In FIG. 12, the beams in each stage in the y direction have the same x-direction coordinates as the beams in the lower stage. Also, the scanning within the sub-irradiation region 29 of each beam is, for example, a repetition of line scanning from bottom to top. Therefore, in the scanning within the sub-irradiation region 29 of each scan, the end point of the first scan line in the lower sub-irradiation region 29 and the start point of the second scan line in the upper sub-irradiation region 29 are close to each other. Similarly, the end point of the k-th scan line and the start point of the (k + 1)-th scan line in the upper sub-irradiation region 29 are close to each other. Therefore, when scanning using M' = 2 or more multi-primary electron beams 20 in the y direction, further improvement is desirable.

[0055] FIG. 13 is a diagram showing an example of the arrangement of sub-irradiation regions in Embodiment 1. In FIG. 13, 29 groups of sub-irradiation regions arranged continuously in the x direction and 29 groups of sub-irradiation regions arranged continuously in the x direction shifted by one in the y direction are arranged with positions shifted in the x direction by a size smaller than the width of the sub-irradiation region 29 in the x direction. As shown in FIG. 13, for example, it is preferable that 29 groups of sub-irradiation regions arranged continuously in the x direction and a sub-irradiation region 29 arranged continuously in the x direction adjacent in the y direction are arranged with positions shifted from each other by p / (2N) in the x direction. Thereby, it is possible to avoid the end point of the k-th scanning line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scanning line in the upper sub-irradiation region 29 from being close to each other. In such a case, for example, a distance of p / (2N) can be set. How much to separate the end point of the k-th scanning line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scanning line in the upper sub-irradiation region 29 may be set according to the influence of charging. When the scanning in all the sub-irradiation regions 29 is performed under the same conditions, as shown in FIG. 13, the distance of half of the x-direction size of the sub-irradiation region 29, and 29 groups of sub-irradiation regions arranged continuously in the x direction and 29 groups of sub-irradiation regions arranged continuously in the x direction shifted by one in the y direction may be shifted in the x direction.

[0056] FIG. 14 is a diagram showing another example of the shaping aperture array substrate in Embodiment 1. In the example of FIG. 14, similar to FIG. 2, holes (openings) 22 in a two-dimensional (matrix) form of M columns in the horizontal (x direction) × M' rows in the vertical (y direction) (M is an integer of 2 or more, M' is an integer of 2 or more) are formed with an array pitch L in the x direction and an array pitch L' in the y direction. As described with reference to FIG. 13, when shifting adjacent sub-irradiation regions 29 in the y direction by a size smaller than the width of the sub-irradiation region 29 in the x direction, it is necessary to change the arrangement of the multi-primary electron beams 20. In the example of FIG. 14, according to the shifting method of FIG. 13, the arrangement of the holes 22 in the shaping aperture array substrate 203 in the horizontal (x direction) M columns × vertical (y direction) M' rows formed in the y direction is changed. For example, when shifting adjacent sub-irradiation regions 29 in the y direction by 1 / 2 of the width of the sub-irradiation region 29 in the x direction in the x direction, the adjacent holes 22 in the y direction may be shifted in the x direction by L / (2N). For example, the positions of the holes 22 in each even row may be shifted by L / (2N) in the -x direction.

[0057] FIG. 15 is a flowchart showing a part of the main process of the inspection method in Embodiment 1. In FIG. 15, among the main processes of the inspection method, the processes from the start to the end of the scanning are shown. In FIG. 15, the inspection method in Embodiment 1 includes a substrate transfer process (S102), an inspection position movement process (S104), a stage movement process (constant speed movement start) (S106), a sub-region scanning process (S108), a determination process (S110), a tracking reset process (S112), a determination process (S114), and a stripe movement process (S116), and a series of these processes are implemented.

[0058] As the substrate transfer process (S102), using a transfer mechanism (not shown), the substrate 101 to be inspected is transferred into the inspection chamber 103 and placed on the XY stage 105.

[0059] As the inspection position movement step (S104), based on the control of the stage control circuit 114, the drive mechanism 142 moves the XY stage 105 so that the inspection position enters the irradiable position of the multi-primary electron beam 20. First, the XY stage 105 is moved so that the irradiation region 34 of the multi-primary electron beam 20 is located on the left end side of the first stripe region 32 (for example, two sizes outside the size of the irradiation region 34).

[0060] As the stage movement step (constant-speed continuous movement start) (S106), based on the control of the stage control circuit 114, the drive mechanism 142 moves the XY stage 105 at a constant speed V in the -x direction, for example. Thereby, the constant-speed continuous movement is started.

[0061] As the sub-region scanning step (S108), the electron optical image acquisition mechanism 150 scans a plurality of sub-irradiation regions 29 (sub-regions; small regions) that are the inspection regions of the substrate 101 for each group of M×M' sub-irradiation regions 29. Specifically, first, based on the control by the deflection control circuit 128, the main deflector 208 uses the multi-primary electron beam 20 to divide the stripe region 32 (inspection region) of the substrate 101 into a plurality of sub-irradiation regions 29 that are obtained in the x direction with a size of p / N (N is an integer of 3 or more) and in the y direction with a size of p' (predetermined size). Among them, the multi-primary electron beam 20 is collectively deflected to M×M' groups of sub-irradiation regions 29 on the substrate 101 arranged in M in the x direction with a pitch p and M' in the y direction. Here, M×M' groups of sub-irradiation regions 29 arranged in the x direction with a pitch p among the plurality of sub-irradiation regions 29 within the irradiation region 34 of the multi-primary electron beam 20 are deflected as the tracking region. The main deflector 208 collectively deflects the multi-primary electron beam 20 to the reference position (for example, the center) of the tracking region. Then, the primary electron optical system 151, which is the illumination optical system, irradiates the substrate 101 with a plurality of multi-primary electron beams 20 arranged in M (M is an integer of 2 or more) in the x direction with the same pitch p and in M' (M' is an integer of 1 or more) in the y direction with the same pitch p' on the surface of the substrate 101. The main deflector 208 performs tracking deflection of the multi-primary electron beam 20 so as to follow the continuous movement of the XY stage 105.

[0062] When M' is 2 or more, as shown in FIG. 13, the sub-irradiation regions 29 adjacent to each other in the y direction are arranged so as to be shifted from each other in the x direction by a size smaller than the width of the sub-irradiation region 29 in the x direction. When M' is 1, it is not necessary to shift the sub-irradiation regions 29 adjacent to each other in the y direction in the x direction.

[0063] Then, while the main deflector 208 starts tracking and the XY stage 105 continuously moves a distance obtained by M / N·p in the -x direction, the multi-primary electron beam 20 is tracking-deflected so as to follow the continuous movement of the XY stage 105, and the M×M' groups of sub-irradiation regions 29 are scanned by the sub-deflector 209.

[0064] Specifically, based on the control by the deflection control circuit 128, the sub-deflector 209 (second deflector) deflects the multi-primary electron beam 20 in a lump so that each beam of the multi-primary electron beam 20 is located at, for example, the lower left pixel 36 of the corresponding sub-irradiation region 29. Actually, the multi-primary electron beam 20 is deflected in a lump so as to be located at, for example, the lower left pixel 36 of a region with a margin added to the corresponding sub-irradiation region 29. Then, while the multi-primary electron beam 20 is being tracking-deflected so as to follow the continuous movement of the XY stage 105, the multi-primary electron beam 20 is deflected in a lump so as to scan the M×M' groups of sub-irradiation regions 29. And at each shot, each beam irradiates one measurement pixel 36 corresponding to the same position within the assigned sub-irradiation region 29. Then, by scanning the entire multi-primary electron beam 20 in a lump in the y direction by the sub-deflector 209, each sub-irradiation region 29 is scanned on the scanning line by the assigned beam. All the measurement pixels 36 within one sub-irradiation region 29 are sequentially irradiated by one beam. Such an operation is performed simultaneously by M×M' multi-primary electron beams 20.

[0065] As a detection process, the multi-detector 222 detects secondary electrons emitted from the substrate 101 due to irradiating the substrate 101 with the multi-primary electron beam 20. Each beam will scan a corresponding one sub-irradiation region 29. By a shot of the multi-primary electron beam 20, secondary electrons are emitted upward from the irradiated measurement pixel 36 each time. In this way, the multi-detector 222 detects secondary electrons emitted from the substrate 101 due to irradiating the substrate 101 with the multi-primary electron beam 20. The multi-detector 222 detects multi-secondary electrons 300 emitted upward from each measurement pixel 36 for each measurement pixel 36.

[0066] As a determination process (S110), when the multi-primary electron beam 20 scans all the measurement pixels 36 within the sub-irradiation region 29 (specifically, the scanning region 31) that each is in charge of, the control computer 110 determines whether the scanning of all the sub-irradiation regions 29 in the target stripe 32 has been completed. If the scanning of all the sub-irradiation regions 29 in the target stripe 32 has been completed, the process proceeds to the determination process (S114). If the scanning of all the sub-irradiation regions 29 in the target stripe 32 has not been completed, the process proceeds to the tracking reset process (S112).

[0067] As a tracking reset process (S112), when all the measurement pixels 36 within the sub-irradiation region 29 (specifically, the scanning region 31) that each is in charge of are scanned by the multi-primary electron beam 20 by the deflection operation of the sub-deflector 209, the main deflector 208 performs tracking reset by collectively deflecting the multi-primary electron beam 20 again to a new group of M×M' sub-irradiation regions 29 arranged in the x direction with a pitch p and M apart in the x direction from M×M' groups of sub-irradiation regions 29 until the movement of the XY stage 105 at a distance obtained by N / M·p in the -x direction is completed. In other words, each time the scanning of a group of M×M' sub-irradiation regions 29 is completed, the main deflector 208 collectively deflects the multi-primary electron beam 20 to a new group of M×M' sub-irradiation regions 29 arranged in the x direction with a pitch p and M apart in the x direction.

[0068] Then, the tracking cycle from the start of such tracking to the tracking reset, and the scanning during tracking are repeated. By repeating such an operation, all the pixels 36 in the stripe region 32 can be scanned.

[0069] As a determination step (S114), the control computer 110 determines whether the scanning of all the stripes 32 has been completed. If the scanning of all the stripes 32 has been completed, the electron optical image acquisition process is terminated. If the scanning of all the stripes 32 has not been completed, the process proceeds to the stripe movement step (S116).

[0070] As the stripe movement step (S116), based on the control of the stage control circuit 114, the drive mechanism 142 moves the XY stage 105 so that the irradiation region 34 of the multi-primary electron beam 20 is positioned at the left end side of the next stripe region 32 (for example, one size outside the size of the irradiation region 34). Then, the above-described respective steps are repeated.

[0071] As described above, the electron optical image acquisition mechanism 150 scans the inspection substrate 101 on which the graphic pattern is formed while continuously moving the XY stage 105 using the multi-primary electron beam 20 formed by a plurality of electron beams. Then, the multi-secondary electrons 300 emitted from the inspection substrate 101 due to the irradiation of the multi-primary electron beam 20 are detected. The manner of scanning and the manner of detecting the multi-secondary electrons 300 are as described above. The detection data of the secondary electrons from each measurement pixel 36 detected by the multi-detector 222 is output to the detection circuit 106 in the order of measurement. In the detection circuit 106, the analog detection data is converted into digital data by an A / D converter (not shown) and stored in the stripe pattern memory 123. Then, when the detection data for one stripe region 32 (or for one chip 332) is accumulated, it is transferred to the comparison circuit 108 together with the information indicating each position from the position circuit 107 as stripe pattern data (or chip pattern data).

[0072] On the other hand, a reference image is created in parallel with or before and after the multi-beam scan and secondary electron detection process.

[0073] As a reference image creation process, the reference image creation circuit 112 creates a reference image of an area corresponding to a measurement image (electron optical image) of a frame area described later based on exposure image data in which an exposure image on the substrate 101 is defined. Instead of the exposure image data, design pattern data that is the source of a plurality of graphic patterns may be used.

[0074] Specifically, it operates as follows. First, the reference image creation circuit 112 reads design pattern data (or exposure image data) from the storage device 109 through the control computer 110. Information such as coordinates (x, y), side lengths, and a graphic code that is an identifier for distinguishing graphic types is defined in the design pattern data (or exposure image data). The shape, size, position, etc. of each pattern graphic are defined by such information.

[0075] Then, the reference image creation circuit 112 converts each graphic pattern in each frame area defined in the read data into binary or multi-value image data. Specifically, when the design pattern data (or exposure image data) is input to the reference image creation circuit 112, it is expanded into data for each graphic, and the graphic code, graphic dimensions, etc. indicating the graphic shape of the graphic data are interpreted. Then, binary or multi-value design image data is expanded and output as a pattern arranged within a grid of a predetermined quantization dimension unit. In other words, the design data is read, the inspection area is virtually divided into grids with a predetermined dimension as a unit, and the occupancy rate of the graphic in the design pattern is calculated for each grid, and n-bit occupancy rate data is output. For example, it is preferable to set one grid as one pixel. And if a resolution of 1 / 2 8 (=1 / 256) is given, a small area of 1 / 256 is allocated for the area of the graphic arranged within the pixel, and the occupancy rate within the pixel is calculated. Therefore, 8-bit occupancy rate data is calculated for each pixel. Such a grid may have the same size as the measurement pixel 36.

[0076] Next, the reference image creation circuit 112 performs appropriate filtering on the design image data, which is the image data of the sent figure. The measurement data as the optical image obtained from the detection circuit 106 is in a state where the filter has acted through the electron optical system. Therefore, filtering is also performed on the design image data, which is the design-side image data with the image intensity (shading value) being a digital value. Thereby, it can be adjusted to the measurement data. In this way, a design image (reference image) to be compared with the measurement image (optical image) of the frame region is created. The image data of the created reference image is output to the comparison circuit 108, and the reference images output into the comparison circuit 108 are each stored in the memory.

[0077] FIG. 16 is a diagram showing the internal configuration of the comparison circuit in Embodiment 1. In FIG. 16, in the comparison circuit 108, storage devices 50 and 52 such as magnetic disk devices, a division unit 56, an alignment unit 58, and a comparison unit 60 are arranged. Each “~ unit” such as the division unit 56, the alignment unit 58, and the comparison unit 60 includes a processing circuit, and the processing circuit includes an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device, etc. Also, each “~ unit” may use a common processing circuit (the same processing circuit). Alternatively, different processing circuits (separate processing circuits) may be used. The necessary input data or the calculated results in the division unit 56, the alignment unit 58, and the comparison unit 60 are stored in a memory (not shown) each time.

[0078] The transferred stripe pattern data (or chip pattern data) is temporarily stored in the storage device 50 together with the information indicating each position from the position circuit 107. Similarly, the reference image data is temporarily stored in the storage device 52 together with the information indicating each position in the design.

[0079] Next, the dividing unit 56 divides the stripe pattern data (or chip pattern data) for each frame area (unit inspection area) to generate a plurality of frame images (inspection images). Since the characteristics of the obtained secondary electron images may shift for each beam, it is desirable to use an image of one unit inspection area as an image obtained by one beam. Therefore, in the first embodiment, it is preferable to use the sub-irradiation area 29 or an area obtained by dividing the sub-irradiation area 29 as the frame area that serves as the unit inspection area.

[0080] Next, the alignment unit 58 aligns the frame image (measurement image) and the reference image in units of sub-pixels smaller than the pixel 36. For example, alignment may be performed by the least squares method.

[0081] Then, the comparison unit 60 compares the frame image (inspection image) with the reference image corresponding to the frame image (inspection image). For example, the comparison unit 60 compares the frame image and the reference image for each pixel 36. The comparison unit 60 compares the two for each pixel 36 according to a predetermined determination condition, and determines the presence or absence of a defect such as a shape defect. For example, if the gradation value difference for each pixel 36 is greater than the determination threshold Th, it is determined as a defect. Alternatively, the inspection accuracy may be reduced compared to the shape defect inspection, and the presence or absence of a pattern disconnection or short circuit may be inspected. Then, the comparison result is output. The comparison result may be output from the storage device 109, the monitor 117, the memory 118, or the printer 119.

[0082] As described above, according to the first embodiment, when acquiring an image using a multi-beam, it is possible to perform a scan in which the end point of the immediately preceding scan and the start point of the next scan are separated by a certain distance or more. Therefore, the influence of charging can be reduced. Therefore, a high-precision image can be obtained.

[0083] Second Embodiment. In Embodiment 1, when M' is 2 or more, the configuration in which adjacent sub-irradiation regions 29 in the y direction are shifted in the x direction by a size smaller than the width of the sub-irradiation region 29 was described. However, it is not limited to this. In Embodiment 2, another configuration will be described. The configuration of the inspection apparatus 100 in Embodiment 2 is the same as that in FIG. 1. Also, the main process steps of the inspection method in Embodiment 2 are the same as those in FIG. 15. Hereinafter, the content other than the points to be particularly described is the same as that in Embodiment 1.

[0084] FIG. 17 is a diagram showing an example of a sub-irradiation region in Embodiment 2. In Embodiment 2, a plurality of sub-irradiation regions 29 (block regions) are formed in a size such that 2 or more sub-irradiation regions 29 are arranged within the beam pitch p' in the y direction. Specifically, the inspection region of the substrate 101 is divided into a plurality of sub-irradiation regions 29 with a size of p / N in the x direction and p' / n (n is an integer of 2 or more) in the y direction. In other words, the sub-irradiation region in Embodiment 1 is divided into 2 or more in the y direction. In the example of FIG. 17, the case where 2 sub-irradiation regions 29 are arranged within the beam pitch p' in the y direction is shown. In the example of FIG. 17, the case where the sizes of the sub-irradiation regions 29 in each stage in the y direction are the same is shown, but it is not limited to this. They may be arranged in different sizes in the y direction.

[0085] And in Embodiment 2, when the number of beams M' in the y direction is 2 or more, there is no need to shift the adjacent sub-irradiation regions 29 in the y direction in the x direction. Therefore, the shaping aperture array substrate 203 may have the configuration shown in FIG. 2.

[0086] In the example of FIG. 17, the case of scanning with the multi-primary electron beam 20 having the number of divisions N = 3, the number of beams M in the x direction being 2, and the number of beams M' in the y direction being 2 is shown. In the first scan, an un-scanned sub-irradiation region 29 can be sandwiched between the sub-irradiation regions 29 scanned by two adjacent beams in the y direction. Therefore, in the scan within each sub-irradiation region 29 for each pass, it is possible to avoid the situation where the end point of the k-th scan line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scan line in the upper sub-irradiation region 29 are close to each other. In such a case, for example, the distance of p' / n can be increased.

[0087] Note that every time the scanning of the M×M' sub-irradiation regions 29 arranged with a pitch p in the x direction and a pitch p' in the y direction is completed by the batch deflection by the sub-deflector 209, the main deflector 208 deflects the multi-primary electron beam 20 in a batch to a new group of M×M' sub-irradiation regions 29 arranged with a pitch p in the x direction and a pitch p' in the y direction and separated by M in the x direction, which is the same as in the first embodiment. Also, the relationship that the number of beams M in the x direction and the number of divisions N are relatively prime to each other and M - 1 is not a multiple of N is the same as in the first embodiment. By repeating such an operation, the scanning of the block region group arranged continuously in the x direction is completed.

[0088] FIG. 18 is a diagram showing an example of a scan stripe region in the second embodiment. In the example of FIG. 18, the case where M' = 4 is shown. Also, the case where n = 2 is shown. In the example of FIG. 18, by the first stripe scan, the lower half region (the first scan stripe region) of the region between each beam in the y direction of the first stripe region 32 is scanned in parallel. Therefore, in the first stripe region 32, the scanning of the upper half region of the region between each beam in the y direction × M' regions remains unperformed. In total, the scanning of 1 / 2 of the region remains unperformed.

[0089] After the scanning of the area of the lower half of the area between the beams in the y-direction of the first stripe region 32 (the first scan stripe region) × M' is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to the second stripe region 32. Then, by the second stripe scan, the area of the lower half of the area between the beams in the y-direction of the second stripe region 32 (the second scan stripe region) is scanned in parallel. Therefore, in the second stripe region 32, the area of the upper half of the area between the beams in the y-direction × M' will remain without being scanned. In total, half of the area will remain without being scanned.

[0090] After the scanning of the area of the lower half of the area between the beams in the y-direction of the second stripe region 32 (the second scan stripe region) × M' is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to the third stripe region 32. Then, by the third stripe scan, the area of the lower half of the area between the beams in the y-direction of the third stripe region 32 (the third scan stripe region) is scanned in parallel. Therefore, in the third stripe region 32, the area of the upper half of the area between the beams in the y-direction × M' will remain without being scanned. In total, half of the area will remain without being scanned.

[0091] After the scanning of the area of the lower half of the area between the beams in the y-direction of the third stripe region 32 (the third scan stripe region) × M' is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to the first stripe region 32. Then, by the fourth stripe scan, the area of the upper half of the area between the beams in the y-direction of the first stripe region 32 (the fourth scan stripe region) is scanned in parallel. Thereby, the scanning of the first stripe region 32 is completed.

[0092] After the scanning of the upper half region (the fourth scan stripe region) × M′ of the regions between the beams in the y-direction of the fourth stripe region 32 is completed, the main deflector 208 deflects the multi-primary electron beam 20 to the second stripe region 32 all at once. Then, by the fifth stripe scan, the upper half region (the fifth scan stripe region) of the regions between the beams in the y-direction of the second stripe region 32 is scanned in parallel. Thereby, the scanning of the second stripe region 32 is completed.

[0093] After the scanning of the upper half region (the fifth scan stripe region) × M′ of the regions between the beams in the y-direction of the fifth stripe region 32 is completed, the main deflector 208 deflects the multi-primary electron beam 20 to the third stripe region 32 all at once. Then, by the sixth stripe scan, the upper half region (the sixth scan stripe region) of the regions between the beams in the y-direction of the third stripe region 32 is scanned in parallel. Thereby, the scanning of the third stripe region 32 is completed.

[0094] As described above, by leaving at least one sub-irradiation region 29 that is not scanned simultaneously in the y-direction and performing scanning, it is possible to avoid the situation where the end point of the k-th scan line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scan line in the upper sub-irradiation region 29 are close to each other. Then, after leaving an un-scanned region within the stripe region 32 and scanning a part of another stripe region 32, return to scan the un-scanned region. Thereby, the un-scanned region can be eliminated.

[0095] FIG. 19 is a diagram showing another example of the scan stripe region in Embodiment 2. In the example of FIG. 19, the case where M' = 4 is shown. Also, the case where n = 2 is shown. In the example of FIG. 19, by the first stripe scan, the lower half regions (first scan stripe regions) × M' of the regions between the beams in the y direction of the first stripe region 32 are scanned in parallel. Therefore, among the first stripe region 32, the upper half regions × M' of the regions between the beams in the y direction remain without being scanned. In total, half of the regions remain without being scanned.

[0096] After the scanning of the lower half regions (first scan stripe regions) × M' of the regions between the beams in the y direction of the first stripe region 32 is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to a position where it has moved by one sub-irradiation region in the y direction. Then, by the second stripe scan, the upper half regions (second scan stripe regions) × M' of the regions between the beams in the y direction of the first stripe region 32 are scanned in parallel. Thereby, the scanning of the first stripe region 32 is completed.

[0097] After the scanning of the upper half regions (second scan stripe regions) × M' of the regions between the beams in the y direction of the first stripe region 32 is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to the first stripe region 32. Then, by the third stripe scan, the lower half regions (third scan stripe regions) × M' of the regions between the beams in the y direction of the second stripe region 32 are scanned in parallel. Therefore, among the second stripe region 32, the upper half regions × M' of the regions between the beams in the y direction remain without being scanned. In total, half of the regions remain without being scanned.

[0098] After the scanning of the lower half region (the third scan stripe region) × M' regions of the region between the beams in the y direction of the second stripe region 32 is completed, the main deflector 208 deflects the multi-primary electron beam 20 all at once to a position where it has moved by one sub-irradiation region in the y direction. Then, by the fourth stripe scan, the upper half region (the fourth scan stripe region) × M' regions of the region between the beams in the y direction of the second stripe region 32 are scanned in parallel. Thereby, the scanning of the second stripe region 32 is completed. Thereafter, by repeating in the same manner, the scanning of each stripe region 32 can be completed.

[0099] As described above, by leaving at least one sub-irradiation region 29 that is not scanned simultaneously in the y direction and performing scanning, it is possible to avoid the situation where the end point of the k-th scan line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scan line in the upper sub-irradiation region 29 are close to each other. Then, after completing the scanning of the region that has not been scanned within the stripe region 32, it moves to the next stripe region 32. Thereby, the region that has not been scanned can be eliminated.

[0100] Embodiment 3. In Embodiment 1, when M' is 2 or more, the configuration in which the adjacent sub-irradiation regions 29 in the y direction are shifted in the x direction by a size smaller than the width of the sub-irradiation region 29 was described. However, it is not limited to this. In Embodiment 3, the case of shifting in the x direction in units of the width of the sub-irradiation region 29 will be described. The configuration of the inspection apparatus 100 of Embodiment 3 is the same as that in FIG. 1. Also, the main process steps of the inspection method of Embodiment 3 are the same as those in FIG. 15. Hereinafter, the content other than the points to be particularly described is the same as that in Embodiment 1.

[0101] FIG. 20 is a diagram showing an example of a sub-irradiation region in Embodiment 3. In Embodiment 3, beams adjacent to each other in the y direction of the multi-primary electron beam 20 are arranged with a shift amount of S×sub-irradiation region 29 (S is an integer of 1 or more) in the x direction relative to each other on the substrate, and their positions are shifted. In the example of FIG. 20, it shows a case where the beam row in the second stage in the y direction irradiates a position shifted by one sub-irradiation region 29 in the -x direction.

[0102] In the example of FIG. 20, it shows a case of scanning with a multi-primary electron beam 20 having a division number N = 4, the number of beams M in the x direction being 3, and the number of beams M' in the y direction being 2 or more (here 3). In the first scan, the sub-irradiation regions 29 scanned by two adjacent beams in the y direction are relatively shifted by one in the x direction. Therefore, in the scan within each sub-irradiation region 29 of each scan, it is possible to avoid the end point of the k-th scan line in the lower sub-irradiation region 29 and the start point of the (k + 1)-th scan line in the upper sub-irradiation region 29 from being close to each other. Also, it is possible to avoid the end point of the scan of the lower sub-irradiation region 20 and the start point of the scan of the upper sub-irradiation region 20 of each scan cycle from being close to each other.

[0103] Note that every time the scan of M×M' sub-irradiation regions 29 arranged with a pitch p in the x direction and a pitch p' in the y direction is completed by the batch deflection by the sub-deflector 209, the main deflector 208 deflects the multi-primary electron beam 20 in a batch to a new group of M×M' sub-irradiation regions 29 arranged with a pitch p in the x direction and a pitch p' in the y direction and separated by M in the x direction, which is the same as in Embodiment 1. Also, the relationship that the number of beams M in the x direction and the division number N are relatively prime to each other and M - 1 is not a multiple of N is the same as in Embodiment 1. By repeating such an operation, the scan of a group of block regions arranged continuously in the x direction is completed.

[0104] FIG. 21 is a diagram for explaining the relationship between the shift amount, the number of beams, and the number of divisions in Embodiment 3. In the example of FIG. 21, a case is shown where the beam row in the second stage in the y direction is shifted by a shift amount S = 2 in the -x direction on the substrate 101. Other configurations are the same as those in FIG. 20. That is, a case of scanning with the multi-primary electron beam 20 where the number of divisions N = 4, the number of beams M in the x direction is 3, and the number of beams M' in the y direction is 2 or more (here, 2). When S = 2, the scanning end point of the lower sub-irradiation region 20 in the first pass and the scanning start point of the upper sub-irradiation region 20 are close to each other. Therefore, a further relationship between the shift amount S, the number of beams M, and the number of divisions N is required.

[0105] In Embodiment 3, as a further relationship, it is necessary that the absolute value of the value obtained by subtracting 1 from the absolute value of the shift amount from the number of beams M in the x direction (|M - |S| - 1|) is not a multiple of N or 0, and S is not a multiple of N. In the example of FIG. 21, when M' is 2 or more, when S = 0, since there is no shift, the same scanning method as in FIG. 12 is obtained, which is NG. When S = 1, the same scanning method as in FIG. 19 is obtained, which is OK. When S = 2, as shown in the example of FIG. 21, it is NG. When S = 3, it is OK, when S = 4, it is NG, when S = 5, it is OK, and when S = 6, it is NG.

[0106] FIG. 22 is a diagram showing another example of the shaping aperture array substrate in Embodiment 3. In the example of FIG. 22, similar to FIG. 2, holes (openings) 22 in a two-dimensional (matrix) form of M columns in the horizontal (x direction) × M' rows in the vertical (y direction) (M is an integer of 2 or more, and M' is an integer of 2 or more) are formed with an array pitch L in the x direction and an array pitch L' in the y direction. As described with FIG. 20, the sub-irradiation regions 29 adjacent to each other in the y direction are shifted in the x direction by S sub-irradiation regions 29. In that case, it is necessary to change the arrangement of the multi-primary electron beams 20. In the example of FIG. 22, according to the shifting method of FIG. 20, the arrangement of the holes 22 in M columns in the horizontal (x direction) × M' rows in the vertical (y direction) formed in the shaping aperture array substrate 203 is changed. For example, when the sub-irradiation regions 29 adjacent to each other in the y direction are shifted in the -x direction by a distance corresponding to one sub-irradiation region 29, the holes 22 adjacent to each other in the y direction may be shifted in the -x direction by S·L / N. For example, the positions of the holes 22 in even rows in the y direction may be shifted in the -x direction by S·L / N.

[0107] By shifting the sub-irradiation regions 29 scanned by the beams adjacent to each other in the y direction in the x direction as described above, the influence of charging can be reduced.

[0108] In the above description, a series of "~ circuits" includes a processing circuit, and the processing circuit includes an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device, etc. Also, each "~ circuit" may use a common processing circuit (the same processing circuit). Or, different processing circuits (separate processing circuits) may be used. The program for causing a processor or the like to execute may be recorded on a recording medium such as a magnetic disk device, a magnetic tape device, an FD, or a ROM (read-only memory).

[0109] The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. In the above example, the case where the XY stage 105 is continuously moved at a constant speed is shown, but it is not limited thereto. From the viewpoint of ease of control, continuous movement at a constant speed is desirable, but continuous movement with acceleration and deceleration may also be acceptable. Also, scanning may be performed by a step-and-repeat method.

[0110] In the above example, the case where the tracking deflection and the deflection for scanning within the sub-irradiation area 29 are performed using a two-stage multi-stage deflector (main deflector 208 and sub-deflector 209) has been shown, but the present invention is not limited to this. It is also suitable to perform deflection control for both the tracking deflection and the deflection for scanning within the sub-irradiation area 29 using the same deflector. In such a case, a voltage obtained by adding the deflection voltage for tracking deflection and the deflection voltage for scanning within the sub-irradiation area 29 may be applied to each electrode constituting the deflector. Such control of the deflection voltage may be performed by the deflection control circuit 128.

[0111] Also, the irradiation order of the beam when scanning within the sub-irradiation area 29 may be arbitrary. However, since the entire multi-primary electron beam 20 is deflected all at once by the sub-deflector 208, the same irradiation order is used between each irradiation area 29.

[0112] In addition, descriptions of parts that are not directly necessary for the description of the present invention, such as the device configuration and control method, etc., have been omitted, but the required device configuration and control method can be appropriately selected and used.

[0113] In addition, all electron beam inspection devices and electron beam inspection methods that include the elements of the present invention and can be appropriately designed and modified by those skilled in the art are included in the scope of the present invention.

Explanation of Reference Numerals

[0114] 17 Pole 18 Electrode 20 Multi-primary electron beam 22 Hole 29 Sub-irradiation area 32 Stripe area 33 Rectangular area 34 Irradiation area 100 Inspection device 101 Substrate 102 Electron beam column 103 Inspection chamber 106 Detection circuit 107 Position circuit 108 Comparison circuit 109 Memory device 110 Control computer 112 Reference image creation circuit 114 Stage control circuit 117 Monitor 118 Memory 119 Printer 120 Bus 122 Laser length measurement system 123 Chip pattern memory 124 Lens control circuit 126 Blanking control circuit 128 Deflection control circuit 132 E×B control circuit 142 Stage drive mechanism 144,146,148 DAC amplifier 150 Image acquisition mechanism 151 Primary electron optical system 152 Secondary electron optical system 160 Control system circuit 200 Electron beam 201 Electron gun 202,205,207 Magnetic lens 203 Shaping aperture array substrate 208 Main deflector 209 Sub-deflector 212 Batch deflector 213 Limiting aperture substrate 214 E×B separator 216 Mirror 218 Deflector 222 Multi-detector 224 Projection lens 226 Deflector 300 Multi-secondary electron beam 301 Secondary electron beam 330 Inspection area 332 Chip

Claims

1. A movable stage on which a substrate to be inspected is placed, an illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface, where M (M is an integer of 2 or more), among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, the multi-beam is collectively deflected to a block region group on the substrate arranged in M in the first direction at the pitch p, and every time the scanning of the block region group is completed, the multi-beam is collectively deflected to a new block region group arranged in M in the first direction at the pitch p and separated by M in the first direction, a first deflector, a second deflector that collectively deflects the multi-beam so as to scan the block region group, a detector that detects secondary electrons emitted from the substrate due to irradiation of the substrate with the multi-beam, comprising, N and M are relatively prime to each other, and M−1 is not a multiple of N, and a block region group arranged continuously in the first direction and a block group arranged continuously in the first direction adjacent in the second direction are arranged with their positions shifted from each other by a size smaller than the width in the first direction of the block region in the first direction. A charged particle beam image acquisition device characterized by this.

2. A movable stage on which a substrate to be inspected is placed, an illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface, where M (M is an integer of 2 or more), among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, the multi-beam is collectively deflected to a block region group on the substrate arranged in M in the first direction at the pitch p, and every time the scanning of the block region group is completed, the multi-beam is collectively deflected to a new block region group arranged in M in the first direction at the pitch p and separated by M in the first direction, a first deflector, a second deflector that collectively deflects the multi-beam so as to scan the block region group, A detector that detects secondary electrons emitted from the substrate due to irradiation of the multi-beam onto the substrate; comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N; Beams adjacent to each other in the second direction of the multi-beam are arranged with a relative displacement of an S block region (S is an integer of 1 or more) in the first direction; A charged particle beam image acquisition device, characterized in that |M - |S| - 1| is not a multiple or 0 of N, and S is not a multiple of N.

3. A movable stage on which a substrate to be inspected is placed; An illumination optical system that irradiates the substrate with a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface (M is an integer of 2 or more); Among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, the multi-beam is collectively deflected to a group of block regions on the substrate arranged in M in the first direction at the pitch p, and every time the scanning of the group of block regions is completed, the multi-beam is collectively deflected to a new group of block regions arranged in M in the first direction at the pitch p and separated by M in the first direction; a first deflector; A second deflector that collectively deflects the multi-beam so as to scan the group of block regions; A detector that detects secondary electrons emitted from the substrate due to irradiation of the multi-beam onto the substrate; comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N; A charged particle beam image acquisition device, characterized in that the plurality of block regions are formed in a size in which two or more block regions are arranged within the beam pitch in the second direction.

4. A step of scanning a group of block regions on the substrate arranged in M in the first direction at the pitch p, among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained by p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, using a multi-beam composed of a plurality of charged particle beams arranged at the same pitch p in the first direction on the substrate surface (M is an integer of 2 or more); Each time the scanning of the M block area groups arranged in the first direction at the pitch p is completed, a step of collectively deflecting the multi-beam to a new block area group arranged in M in the first direction and separated by M in the first direction; Each time the scanning of the block area groups arranged continuously in the first direction is completed, a step of collectively deflecting the multi-beam to a new block area group arranged in M at the pitch p adjacent in the second direction; A step of detecting secondary electrons emitted from the substrate due to irradiation of the multi-beam on the substrate; comprising; N and M are relatively prime to each other, and M−1 is not a multiple of N, and the block area groups arranged continuously in the first direction and the block groups arranged continuously in the first direction adjacent in the second direction are arranged such that their positions are shifted from each other by a size smaller than the width of the block area in the first direction in the first direction. A charged particle beam image acquisition method characterized by this.

5. Using a multi-beam composed of M (M is an integer of 2 or more) charged particle beams arranged at the same pitch p on the substrate surface in the first direction, the inspection area of the substrate is p / N (N is an integer of 3 or more) in the first direction. Among a plurality of block areas obtained in size and divided into a predetermined size in a second direction orthogonal to the first direction, a step of scanning a block area group on the substrate arranged in M at the pitch p in the first direction; Each time the scanning of the block area group arranged in M at the pitch p is completed, a step of collectively deflecting the multi-beam to a new block area group arranged in M at the pitch p and separated by M in the first direction; A step of detecting secondary electrons emitted from the substrate due to irradiation of the multi-beam on the substrate; comprising; N and M are relatively prime to each other, and M−1 is not a multiple of N; The beams adjacent to each other in the second direction of the multi-beam are arranged with their positions shifted by S block areas (S is an integer of 1 or more) relative to each other in the first direction; A charged particle beam image acquisition method characterized in that |M−|S|−1| is not a multiple or 0 of N, and S is not a multiple of N.

6. Using a multi-beam composed of a plurality of charged particle beams arranged in the first direction on the substrate surface at the same pitch p, among a plurality of block regions obtained by dividing the inspection region of the substrate into a size obtained at p / N (N is an integer of 3 or more) in the first direction and a predetermined size in a second direction orthogonal to the first direction, a step of scanning a block region group on the substrate in which M are arranged at the pitch p in the first direction; A step of collectively deflecting the multi-beam to a new block region group in which M are arranged at the pitch p in the first direction, which is M apart in the first direction, each time the scanning of the block region group in which M are arranged at the pitch p is completed; A step of detecting secondary electrons emitted from the substrate due to irradiating the substrate with the multi-beam; comprising; N and M are relatively prime to each other, and M - 1 is not a multiple of N; The plurality of block regions are formed in a size in which two or more block regions are arranged within the beam pitch in the second direction. A charged particle beam image acquisition method characterized by this.

Images