JP2018137358A - Multiple charged particle beam lithography method and multiple charged particle beam lithography system - Google Patents

Abstract

PURPOSE: To provide a lithography method capable of reducing the influence of defective beams in multiple beam lithography regardless of the defective beams that may occur during lithography.CONSTITUTION: A multiple charged particle beam lithography method of an embodiment of the present invention includes the steps of: forming multiple beams by allowing a part of charged particle beams to pass through each of a plurality of openings of a molded aperture array substrate having the plurality of openings formed therein; and drawing a plurality of small areas using the multiple beams so that small areas adjacent to each other in the plurality of small areas that are obtained by dividing a lithography area of a sample, each small area being a minimum irradiation unit area per beam of the multiple beams, are not irradiated with beams passing through the same opening of the plurality of openings.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a multi-charged particle beam drawing method and a multi-charged particle beam drawing apparatus, and for example, relates to a countermeasure method for a defective beam in multi-beam drawing.

  Lithography technology, which is responsible for the progress of miniaturization of semiconductor devices, is an extremely important process for generating a pattern among semiconductor manufacturing processes. In recent years, with the high integration of LSI, circuit line widths required for semiconductor devices have been reduced year by year. Here, the electron beam (electron beam) drawing technique has an essentially excellent resolution, and drawing is performed on a wafer or the like using an electron beam.

  In the variable shaping (VSB) type electron beam drawing which draws with one electron beam, it is necessary to divide the pattern into fine shot figures as the pattern becomes more complicated. Then, the drawing time becomes longer accordingly. In order to compensate for the increase in the number of shots, it is conceivable to shorten the writing time by increasing the current density of the beam. However, since the influence of resist heating or the like becomes large, this method has a limit.

  Here, there is a drawing apparatus using a multi-beam. Compared with the case of drawing with one electron beam, the use of multi-beams enables irradiation with many beams at a time, so that the throughput can be significantly improved. In such a multi-beam type drawing apparatus, for example, an electron beam emitted from an electron gun is passed through a mask having a plurality of holes arranged in a matrix to form a multi-beam, each of which is blanked and shielded. Each beam which has not been deflected is deflected by a deflector and irradiated to a desired position on the sample. In such a multi-beam type drawing apparatus, since a plurality of beams are irradiated at once, the influence of the pattern shape on the drawing time is smaller than that of the variable shaping method.

  Here, in multi-beam drawing, the irradiation amount of each beam is individually controlled by the irradiation time. In order to control the irradiation amount of each beam with high accuracy, it is necessary to perform blanking control for turning on / off the beam at high speed. In the multi-beam type drawing apparatus, each multi-beam passage hole is formed, and a pair of blanking electrodes (blankers) and a control circuit (LSI circuit) for blanking each beam are formed around each of the through-holes. Is installed. The blanking aperture array (BAA) apparatus uses a micro electro mechanical systems (MEMS) technology to form a through hole and a pair of blanking electrodes, etc. on a silicon (Si) substrate (for example, Patent Document 1). reference). However, it is difficult to produce a defect-free BAA device with the current scientific and technological level. A typical defect (defective beam) of the BAA apparatus includes a bright spot (cannot turn off the beam with an aperture: the beam cannot be cut) and a dark spot (cannot turn on the beam with the aperture: no beam is emitted). In multi-beam writing, since it is used in an environment in which an electron beam having an acceleration voltage of, for example, several tens of keV is irradiated, the number of defects in the BAA apparatus increases as the usage time elapses. For example, if there are three BAA devices with a defect rate increase rate of 1%, 5%, and 10% per year, the expected interval until a new defect is newly generated is 13 hours and 2 hours, respectively. And there are cases where it is estimated to be 1 hour. If the time for drawing one mask with the multi-beam drawing apparatus is about 10 hours, the number of defects in the BAA apparatus increases during the drawing.

  Therefore, when the drawing process is performed only considering the defects of the BAA apparatus confirmed before the drawing process is started, the drawing result is greatly affected by the defects generated during the drawing. Even if the defect is confirmed during the drawing, the drawing result is affected by the defect newly generated during the checking operation.

Japanese Unexamined Patent Publication No. 2006-054285

  Therefore, one embodiment of the present invention provides a drawing apparatus and method capable of reducing the influence of a defect beam in multi-beam writing regardless of a defect beam that may occur during writing.

The multi-charged particle beam writing method of one embodiment of the present invention includes:
Forming a multi-beam by passing a part of the charged particle beam through each of the plurality of openings of the shaped aperture array substrate in which the plurality of openings are formed;
The sample drawing area is divided so that the adjacent small areas of the plurality of small areas that are the minimum irradiation unit area per beam of the multi-beam are not irradiated with beams that have passed through the same opening of the plurality of openings. Drawing a plurality of small areas using a beam;
It is provided with.

  In addition, among the plurality of small regions, the small region group irradiated with the beam that has passed through the same opening portion is shifted by shifting the small regions adjacent in the first direction in the second direction orthogonal to the first direction. Preferably it is set.

Further, the value m ₁ (the integer of m ₁ ≧ 2) of the total number of small areas in the first direction and the value m ₂ (m ₂ of the total number of small areas in the second direction) arranged at the inter-beam pitch of the multi-beams. For a plurality of adjacent reference regions that are configured by m ₁ column × m ₂ column small region groups using an integer of ≧ 2, small regions that have the same positional relationship between adjacent reference regions It is preferable that a plurality of reference regions be drawn while shifting the irradiation position so that the beam does not irradiate with the beam that has passed through the same opening.

  In addition, among the small group areas in each reference area of a plurality of reference areas, the reciprocal number of the value obtained by dividing the number of small areas irradiated by the beam that has passed through the same opening by the total number of small areas in each reference area When a plurality of reference regions are drawn while shifting the irradiation position so that the small regions having the same positional relationship between the reference regions of the same set are not irradiated by the beams that have passed through the same opening, Is preferred.

A multi-charged particle beam drawing apparatus according to an aspect of the present invention includes:
A stage capable of continuous movement on which a sample coated with resist is placed;
An emission source that emits a charged particle beam;
A plurality of apertures are formed, and a part of the charged particle beam passes through each of the plurality of apertures, thereby forming a multi-beam aperture substrate,
A blanking aperture array mechanism in which a plurality of blankers that perform blanking deflection of the corresponding beams among the multi-beams that have passed through the plurality of openings are arranged;
A limiting aperture substrate that blocks each beam deflected to be in a beam OFF state by a plurality of blankers;
A deflector that deflects multiple beams at once;
A deflector that divides the drawing area of the sample and prevents the adjacent small areas of the multiple small areas that are the minimum irradiation area per beam of the multi-beam from being irradiated with the beams that have passed through the same opening of the multiple openings. A deflection control circuit for controlling the deflector so that the multi-beam deflects at once.
It is provided with.

  According to one embodiment of the present invention, the influence of a defect beam in multi-beam writing can be reduced regardless of a defect beam that may occur during writing. Therefore, a highly accurate pattern can be drawn.

1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to Embodiment 1. FIG. FIG. 3 is a conceptual diagram showing a configuration of a molded aperture array substrate in the first embodiment. FIG. 3 is a cross-sectional view showing a configuration of a blanking aperture array mechanism in the first embodiment. FIG. 3 is a top conceptual view showing a part of the configuration in the membrane region of the blanking aperture array mechanism in the first embodiment. It is a figure which shows an example of the separate blanking mechanism of Embodiment 1. FIG. 7 is a conceptual diagram for explaining an example of a drawing operation in Embodiment 1. FIG. 3 is a diagram illustrating an example of a multi-beam irradiation region and a pixel on a sample surface in Embodiment 1. FIG. 6 is a diagram illustrating an example of a drawing sequence according to Embodiment 1. FIG. 6 is a diagram showing an example of a drawing sequence in a reference area in Embodiment 1. FIG. It is a figure which shows an example of the calculation result of the dose profile in the state without a defect beam in the comparative example of Embodiment 1. FIG. 6 is a diagram illustrating an example of a calculation result of a dose profile in the first embodiment. FIG. FIG. 10 is a diagram showing another example of a drawing sequence in the second embodiment. FIG. 10 is a diagram illustrating another example of a calculation result of a dose profile in the second embodiment. FIG. 10 is a diagram illustrating an example of a reference region in the third embodiment. It is a figure which shows an example of the pixel arrangement | sequence in Embodiment 4 and a comparative example. FIG. 10 is a diagram illustrating an example of a drawing sequence with different y-direction shift amounts in the fourth embodiment and a comparative example. FIG. 10 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and a comparative example. FIG. 10 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and a comparative example. FIG. 10 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and a comparative example. FIG. 20 is a diagram showing an example of a drawing sequence in the fifth embodiment. FIG. 25 is a diagram showing another example of a drawing sequence in the fifth embodiment. FIG. 25 is a diagram showing another example of a drawing sequence in the fifth embodiment.

  Hereinafter, in the embodiment, a configuration using an electron beam will be described as an example of a charged particle beam. However, the charged particle beam is not limited to an electron beam, and a beam using charged particles such as an ion beam may be used.

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to the first embodiment. In FIG. 1, the drawing apparatus 100 includes a drawing mechanism 150 and a control system circuit 160. The drawing apparatus 100 is an example of a multi charged particle beam drawing apparatus. The drawing mechanism 150 includes an electron column 102 (multi-electron beam column) and a drawing chamber 103. In the electron column 102, an electron gun 201, an illumination lens 202, a shaping aperture array substrate 203, a blanking aperture array mechanism 204, a reduction lens 205, a limiting aperture substrate 206, an objective lens 207, and a deflector 208 are arranged. . An XY stage 105 is disposed in the drawing chamber 103. On the XY stage 105, a sample 101 such as a mask blank coated with a resist to be a drawing target substrate at the time of drawing is arranged. The sample 101 includes an exposure mask for manufacturing a semiconductor device, or a semiconductor substrate (silicon wafer) on which the semiconductor device is manufactured. On the XY stage 105, a mirror 210 for measuring the position of the XY stage 105 is further arranged.

  The control system circuit 160 includes a control computer 110, a memory 112, a deflection control circuit 130, a digital / analog conversion (DAC) amplifier unit 132, a stage position detector 139, and a storage device 140 such as a magnetic disk device. The control computer 110, the memory 112, the deflection control circuit 130, the stage position detector 139, and the storage device 140 are connected to each other via a bus (not shown). A DAC amplifier unit 132 and a blanking aperture array mechanism 204 are connected to the deflection control circuit 130. The output of the DAC amplifier unit 132 is connected to the deflector 208. The stage position detector 139 irradiates the mirror 210 on the XY stage 105 with laser light and receives the reflected light from the mirror 210. Then, the position of the XY stage 105 is measured using the information of the reflected light.

  In the control computer 110, a pixel dividing unit 50, a reference area setting unit 51, a settling time calculation unit 52, a pattern density ρ calculation unit 53, a corrected irradiation coefficient Dp (x) calculation unit 54, and an incident irradiation amount D (x) calculation. A unit 56, an irradiation time t calculation unit 58, and a drawing control unit 60 are arranged. Pixel division unit 50, reference region setting unit 51, settling time calculation unit 52, pattern density ρ calculation unit 53, corrected irradiation coefficient Dp (x) calculation unit 54, incident dose D (x) calculation unit 56, irradiation time t calculation Each “˜ unit” such as the unit 58 and the drawing control 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. In addition, each “˜unit” may use a common processing circuit (the same processing circuit). Alternatively, different processing circuits (separate processing circuits) may be used. Pixel division unit 50, reference region setting unit 51, settling time calculation unit 52, pattern density ρ calculation unit 53, corrected irradiation coefficient Dp (x) calculation unit 54, incident dose D (x) calculation unit 56, irradiation time t calculation Necessary input data or calculation results in the unit 58 and the drawing control unit 60 are stored in the memory 112 each time.

  In addition, drawing data is input from the outside of the drawing apparatus 100 and stored in the storage device 140. In the drawing data, information on a plurality of graphic patterns for drawing is usually defined. Specifically, a graphic code, coordinates, size, and the like are defined for each graphic pattern.

  Here, FIG. 1 shows a configuration necessary for explaining the first embodiment. The drawing apparatus 100 may normally have other necessary configurations.

  FIG. 2 is a conceptual diagram showing the configuration of the molded aperture array substrate in the first embodiment. 2, holes (openings) 22 in vertical (y direction) p rows × horizontal (x direction) q rows (p, q ≧ 2) 22 are formed in a matrix at a predetermined arrangement pitch on the molded aperture array substrate 203. Is formed. In FIG. 2, for example, 512 × 512 rows of holes 22 are formed in the vertical and horizontal directions (x and y directions). Each hole 22 is formed of a rectangle having the same size and shape. Alternatively, it may be a circle having the same diameter. When a part of the electron beam 200 passes through each of the plurality of holes 22, the multi-beam 20 is formed. Here, an example in which two or more holes 22 are arranged in both the vertical and horizontal directions (x and y directions) is shown, but the present invention is not limited to this. For example, either one of the vertical and horizontal directions (x and y directions) may be a plurality of rows and the other may be only one row. Further, the arrangement of the holes 22 is not limited to the case where the vertical and horizontal directions are arranged in a lattice pattern as shown in FIG. For example, the holes in the vertical direction (y direction) k-th row and the (k + 1) -th row may be arranged so as to be shifted in the horizontal direction (x direction) by a dimension a. Similarly, the holes in the vertical (y direction) k + 1-th row and the k + 2-th row may be arranged so as to be shifted in the horizontal direction (x direction) by a dimension b.

FIG. 3 is a cross-sectional view showing the configuration of the blanking aperture array mechanism in the first embodiment.
FIG. 4 is a top conceptual view showing a part of the configuration in the membrane region of the blanking aperture array mechanism in the first exemplary embodiment. 3 and 4, the positional relationship among the control electrode 24, the counter electrode 26, the control circuit 41, and the pad 43 is not shown to be the same. In the blanking aperture array mechanism 204, as shown in FIG. 3, a semiconductor substrate 31 made of silicon or the like is disposed on a support base 33. For example, the central portion of the substrate 31 is thinly cut from the back surface side and processed into a membrane region 330 (first region) having a thin film thickness h. The periphery surrounding the membrane region 330 is an outer peripheral region 332 (second region) having a thick film thickness H. The upper surface of the membrane region 330 and the upper surface of the outer peripheral region 332 are formed so as to have the same height position or substantially the height position. The substrate 31 is held on the support base 33 on the back surface of the outer peripheral region 332. The central portion of the support base 33 is open, and the position of the membrane region 330 is located in the open area of the support base 33.

  In the membrane region 330, passage holes 25 (openings) for passing the respective multi-beams are opened at positions corresponding to the respective holes 22 of the shaped aperture array substrate 203 shown in FIG. In other words, in the membrane region 330 of the substrate 31, a plurality of through holes 25 through which the corresponding beams of multi-beams using electron beams pass are formed in an array. A plurality of electrode pairs each having two electrodes are arranged on the membrane region 330 of the substrate 31 at positions facing each other across the corresponding passage hole 25 among the plurality of passage holes 25. Specifically, as shown in FIGS. 3 and 4, the blanking deflection control electrode 24 and the counter electrode 26 are sandwiched on the membrane region 330 with the passage holes 25 in the vicinity of the passage holes 25 interposed therebetween. Each set (blanker: blanking deflector) is arranged. A control circuit 41 (logic circuit) for applying a deflection voltage to the control electrode 24 for each passage hole 25 is disposed in the substrate 31 and in the vicinity of each passage hole 25 on the membrane region 330. The counter electrode 26 for each beam is grounded.

  Also, as shown in FIG. 4, each control circuit 41 is connected with n-bit (for example, 10-bit) parallel wiring for control signals. Each control circuit 41 is connected to a clock signal line, a read signal, a shot signal, a power supply line, and the like in addition to an n-bit parallel wiring for a control signal. For the clock signal line, the read signal, the shot signal, and the power supply wiring, a part of the parallel wiring may be used. An individual blanking mechanism 47 including the control electrode 24, the counter electrode 26, and the control circuit 41 is configured for each beam constituting the multi-beam. In the example of FIG. 3, the control electrode 24, the counter electrode 26, and the control circuit 41 are arranged in the membrane region 330 where the substrate 31 is thin. However, the present invention is not limited to this. The plurality of control circuits 41 formed in an array on the membrane region 330 are grouped by, for example, the same row or the same column, and the control circuits 41 in the group are connected in series as shown in FIG. Is done. Then, a signal from the pad 43 arranged for each group is transmitted to the control circuit 41 in the group. Specifically, a shift register (not shown) is arranged in each control circuit 41. For example, among the p × q multi-beams, shift registers in the control circuit 41 of the beam in the same row, for example, are connected in series. . Then, for example, control signals for beams in the same row of p × q multi-beams are transmitted in series, and the control signals for each beam are stored in the corresponding control circuit 41 by, for example, p clock signals.

  FIG. 5 is a diagram illustrating an example of the individual blanking mechanism according to the first embodiment. In FIG. 5, an amplifier 46 (an example of a switching circuit) is disposed in the control circuit 41. In the example of FIG. 5, a CMOS (Complementary MOS) inverter circuit is disposed as an example of the amplifier 46. The CMOS inverter circuit is connected to a positive potential (Vdd: blanking potential: first potential) (for example, 5 V) (first potential) and a ground potential (GND: second potential). An output line (OUT) of the CMOS inverter circuit is connected to the control electrode 24. On the other hand, a ground potential is applied to the counter electrode 26. A plurality of control electrodes 24 to which a blanking potential and a ground potential can be switched are provided on the substrate 31, and a plurality of counter electrodes 26 sandwiching the corresponding passage holes 25 of the plurality of passage holes 25. Are arranged at positions facing the corresponding counter electrodes 26 respectively.

  The input (IN) of the CMOS inverter circuit is either an L (low) potential (eg, ground potential) that is lower than the threshold voltage or an H (high) potential (eg, 1.5 V) that is equal to or higher than the threshold voltage. Is applied as a control signal. In the first embodiment, in a state where the L potential is applied to the input (IN) of the CMOS inverter circuit, the output (OUT) of the CMOS inverter circuit becomes a positive potential (Vdd), which is due to the potential difference from the ground potential of the counter electrode 26. The beam corresponding to the multi-beam 20 is deflected by an electric field and shielded by the limiting aperture substrate 206 so that the beam is turned off. On the other hand, in a state where the H potential is applied to the input (IN) of the CMOS inverter circuit (active state), the output (OUT) of the CMOS inverter circuit becomes the ground potential, and the potential difference from the ground potential of the counter electrode 26 disappears. Since the 20 corresponding beams are not deflected, the beam is controlled to be turned on by passing through the limiting aperture substrate 206.

  Each of the multi-beams 20 passing through each through hole is deflected by a voltage applied to two control electrodes 24 and a counter electrode 26 which are independently paired. Blanking is controlled by such deflection. Specifically, the set of the control electrode 24 and the counter electrode 26 individually blanks and deflects the corresponding beam of the multi-beam 20 by a potential switched by a CMOS inverter circuit serving as a corresponding switching circuit. As described above, the plurality of blankers perform blanking deflection of the corresponding beams among the multi-beams that have passed through the plurality of holes 22 (openings) of the shaping aperture array substrate 203.

  FIG. 6 is a conceptual diagram for explaining an example of the drawing operation in the first embodiment. As shown in FIG. 6, the drawing area 30 of the sample 101 is virtually divided into a plurality of strip-shaped stripe areas 32 having a predetermined width in the y direction, for example. First, the XY stage 105 is moved and adjusted so that the irradiation region 34 that can be irradiated with one shot of the multi-beam 20 is positioned at the left end of the first stripe region 32 or further on the left side. Is started. When drawing the first stripe region 32, the drawing is relatively advanced in the x direction by moving the XY stage 105 in the −x direction, for example. The XY stage 105 is continuously moved at a constant speed, for example. After drawing of the first stripe region 32, the stage position is moved in the -y direction, and the irradiation region 34 is relatively positioned in the y direction at the right end of the second stripe region 32 or further to the right side. This time, the XY stage 105 is moved in the x direction, for example, so that the drawing is similarly performed in the −x direction. In the third stripe region 32, drawing is performed in the x direction, and in the fourth stripe region 32, drawing is performed while alternately changing the orientation, such as drawing in the −x direction. Can be shortened. However, the drawing is not limited to the case of alternately changing the direction, and when drawing each stripe region 32, the drawing may be advanced in the same direction. In one shot, a plurality of shot patterns as many as the maximum number of holes 22 are formed at a time by the multi-beams formed by passing through the holes 22 of the shaped aperture array substrate 203.

  Here, as described above, in reality, among the many control electrodes 24 arranged in the blanking aperture array mechanism 204, the potential applied to some of the control electrodes 24 is fixed to a positive potential (Vdd). The beam passing through the individual blanking mechanism 47 having the control electrode 24 fixed to the positive potential (Vdd) of the blanking aperture array mechanism 204 is a defective beam of a dark spot (a state in which the beam cannot be turned on by fixing the beam OFF). Become. Alternatively, the beam passing through the individual blanking mechanism 47 having the control electrode 24 fixed to the ground potential and fixed to the ground potential of the blanking aperture array mechanism 204 is a bright spot (the beam cannot be turned off by fixing the beam ON). It becomes a defect beam.

  Here, the beams that pass through the same hole 22 of the shaped aperture array substrate 203 pass through the corresponding through hole 25 (individual blanking mechanism 47) of the blanking aperture array mechanism 204. Therefore, in the first embodiment, the irradiation position of the multi-beam 20 is devised so that each beam passing through the same hole 22 of the shaping aperture array substrate 203 forming the multi-beam 20 does not irradiate adjacent pixels 36 described later. To do.

  As the pixel dividing step, the pixel dividing unit 50 divides the stripe region 32 into a plurality of pixels 36 according to the arrangement state of the multi-beams 20.

  FIG. 7 is a diagram illustrating an example of a multi-beam irradiation region and a pixel on the sample surface in the first embodiment. The p × q multi-beams 20 are irradiated with a pitch P in the x and y directions on the surface of the sample 101. Accordingly, the stripe region 32 is divided into a plurality of mesh regions in a mesh shape with the beam size of the multi-beam 20, for example. For example, a size of about 10 nm is preferable. Each mesh area is a drawing target pixel 36 (minimum irradiation unit area, irradiation position, or drawing position). The size of the drawing target pixel 36 is not limited to the beam size, and may be an arbitrary size regardless of the beam size. For example, the beam size may be 1 / n (n is an integer of 1 or more). The mesh area (pixel 36) is a minimum irradiation unit area per beam of the multi-beam. In the example of FIG. 6, the drawing region of the sample 101 has, for example, a plurality of stripe regions 32 having substantially the same width as the size of the irradiation region 34 (drawing field) that can be irradiated by one irradiation of the multibeam 20 in the y direction. It shows the case where it is divided. The width of the stripe region 32 is not limited to this. It is preferable that the size is n times the irradiation area 34 (n is an integer of 1 or more).

As a reference region setting step, the reference region setting unit 51 combines a plurality of divided pixels 36 to select four pixels 28 irradiated with four adjacent beams by one multi-beam shot. A reference region 33 constituted by a pixel group substantially surrounded by the four pixels 28 is set. In other words, the reference region setting unit 51 forms the reference region 33 with a plurality of pixels arranged at the inter-beam pitch P in the x and y directions starting from the pixel 28 irradiated in the first shot. In the example of FIG. 7, in other words, the pitch between the adjacent pixels 28 becomes the pitch P between the beams of the multi-beam. In the inter-beam pitch of the multi-beam 20, m ₁ (m ₁ ≧ 2 integer) in the x direction and m ₂ (m ₂ ≧ 2 integer) m ₁ × m _{2 in} the y direction. The pixels 36 are divided so as to be arranged. One reference region 33 is constituted by a rectangular region surrounded by four adjacent pixels 28 and including one pixel 28 of the four pixels 28. In the example of FIG. 7, a case where 16 × 16 (total 256) pixels 36 are arranged in the reference region 33 of the multi-beam 20 is illustrated.

  Here, there is a method of irradiating all the pixels 36 in the reference region 33 by sequentially shooting the same reference region 33 with one beam. However, when such a beam is the above-described defect beam, all the pixels 36 in the reference region 33 are drawn by the defect beam. This causes an error in the dimension of the pattern portion formed by the reference region 33. Therefore, a drawing sequence is set so that pixels as close as possible are not irradiated with the same defect beam.

Therefore, in the first embodiment, all the pixels 36 in the reference region 33 are not irradiated with all the pixels 36 with the beam that has passed through the same hole 22, but are irradiated with pixels 36 that are substantially equidistant or separated by a certain distance or more. To do. For example, when irradiating M times with a beam that has passed through the same hole 22 out of 16 × 16 (total 256) pixels 36 constituting the reference region 33,
M / 256 reference areas 33 are used, and the M / 256 reference areas 33 are drawn so that no gap is formed when they are (virtually) overlapped.

  Therefore, in the first embodiment, the number of pixels irradiated with the beam that has passed through the same hole 22 among the plurality of pixels 36 in each reference region 33 of the plurality of reference regions 33 is set to each reference region 33 of the plurality of reference regions 33. A reference region 33 having a reciprocal number of the value divided by the total number of pixels is taken as one set. In the first embodiment, the irradiation positions are shifted so that the pixels 36 having the same positional relationship in the same reference region 33 are not irradiated by the beams that have passed through the same hole 22 between the same reference regions 33. A plurality of reference areas 33 are drawn.

  FIG. 8 is a diagram illustrating an example of a drawing sequence according to the first embodiment. In the example of FIG. 8, the stripe region 32 is divided into a plurality of regions by a reference region 33 in which a plurality of 16 × 16 pixels 36 are arranged. The black dots in FIG. 8 indicate the pixels in the 16 reference regions 33 while performing irradiation 4 × 4 times (= 16 times) per reference region 33 on the beam that has passed through the same hole 22 of the shaped aperture array substrate 203. The example of arrangement | positioning of the irradiation pixel in the case of irradiating is represented. Therefore, in the example of FIG. 8, the number of 4 × 4 (= 16) pixels irradiated with the beam that has passed through the same hole 22 among the plurality of 16 × 16 pixels 36 in each reference region 33 is set to each reference. A reciprocal number (16) reference regions 33 of a value (1/16) divided by the number of 16 × 16 pixels in the region 33 is taken as one set. Therefore, in the example of FIG. 8, 16 reference regions 33 arranged adjacent to each other in the x direction are illustrated. Then, for each shot of the multi-beam 20, the irradiation position of the beam in the reference region 33 that each beam of the multi-beam 20 takes charge irradiates while shifting by a predetermined number of pixels. Further, when irradiation while shifting by a predetermined number of pixels in one reference region 33 is completed, the corresponding beam is irradiated in the same manner while shifting to the adjacent reference region 33. Therefore, in the example of FIG. 8, a case where the beam that has passed through the same hole 22 irradiates pixels in 16 reference regions 33 while performing irradiation 4 × 4 times (= 16 times) per reference region 33. Show. At this time, a plurality of reference positions are shifted while the irradiation positions are shifted so that the pixels 36 having the same positional relationship in the reference area 33 between the adjacent reference areas 33 are not irradiated by the beam that has passed through the same hole 22 of the shaped aperture array substrate 203. An area 33 is drawn.

  FIG. 9 is a diagram showing an example of a drawing sequence in the reference area in the first embodiment. In the example of FIG. 9, in the first shot, each beam of the multi-beam 20 irradiates the lowermost pixel 36 in the y direction in the first column in the x direction from the left of the target reference region 33. In the second shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the fifth row from the bottom in the y direction. In the third shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the ninth row from the bottom in the y direction. In the fourth shot, each beam of the multi-beam 20 irradiates the 13th pixel 36 in the first row from the left and the 13th row from the bottom in the y direction of the same reference region 33 from the left. With the four shots from the first time to the fourth time, each reference region 33 is irradiated with 4 pixels at a 4 pixel pitch among the 16 pixels in the first column in the x direction.

In the fifth shot, each beam of the multi-beam 20 irradiates the lowermost pixel 36 in the y direction in the fifth column in the x direction from the left of the target reference region 33. In the sixth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the fifth row from the left in the x direction and the fifth row from the bottom in the y direction from the left of the target reference region 33. In the seventh shot, each beam of the multi-beam 20 irradiates the pixel 36 in the fifth row from the left of the target reference region 33 in the x direction and the ninth row from the bottom in the y direction. In the eighth shot, each beam of the multi-beam 20 irradiates the pixels 36 in the fifth row from the left of the target reference region 33 in the x direction and the thirteenth pixel from the bottom in the y direction.

  In the ninth shot, each beam of the multi-beam 20 irradiates the pixel 36 at the bottom in the y direction in the ninth column from the left of the same reference region 33 in the x direction. In the tenth shot, each beam of the multi-beam 20 irradiates the ninth row of pixels 36 in the x direction from the left and the fifth row from the bottom in the y direction of the same reference region 33. In the eleventh shot, each beam of the multi-beam 20 irradiates the ninth row of pixels 36 in the x direction from the left and the ninth row from the bottom in the y direction of the same reference region 33. In the twelfth shot, each beam of the multi-beam 20 irradiates the thirteenth pixel 36 in the x direction from the left and the thirteenth stage from the bottom in the y direction of the same reference region 33.

  In the thirteenth shot, each beam of the multi-beam 20 irradiates the pixel 36 at the lowermost stage in the 13th column in the x direction from the left of the same reference region 33 and in the y direction. In the 14th shot, each beam of the multi-beam 20 irradiates the 13th column in the x direction from the left of the same reference region 33 and the fifth stage pixel 36 from the bottom in the y direction. In the fifteenth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the ninth row from the bottom in the 13th column in the x direction and the y direction from the left of the same reference region 33. In the sixteenth shot, each beam of the multi-beam 20 irradiates the thirteenth row of pixels 36 from the left of the same reference region 33 in the 13th column from the left in the x direction and from the bottom in the y direction.

  As described above, with 16 shots, 16 × 16 pixels 36 in the same reference region 33 pass 4 × 4 (= 16) pixels at the same pixel pitch through the same individual blanking mechanism 47 (same The beam that has passed through the hole 22 is irradiated. Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 8, 16 shots are similarly performed at a position shifted by one pixel in the y direction with respect to a reference area 33 (for example, the second reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the third reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the fourth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. With this operation, among the 16 × 16 pixels 36 in each reference region 33, all 16 pixels in the y direction in the 1, 5, 9, and 13th columns in the x direction are irradiated.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 8, with respect to a reference region 33 adjacent in the x direction (for example, the fifth reference region 33), a position shifted by one pixel in the x direction is similarly applied from the pixel 36 at the lowest stage in the y direction. , Perform 16 shots. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference area 33 (for example, the sixth reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the seventh reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the eighth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. With this operation, among the 16 × 16 pixels 36 in each reference region 33, all the 16 pixels in the y direction in the 2, 6, 10, and 14 columns in the x direction are irradiated.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 8, with respect to a reference region 33 (for example, the ninth reference region 33) adjacent in the x direction, the position shifted by one pixel in the x direction is the same from the bottommost pixel 36 in the y direction. In addition, 16 shots are performed. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference region 33 (for example, the tenth reference region 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 11th reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the twelfth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. With this operation, among the 16 × 16 pixels 36 in each reference region 33, all the 16 pixels in the y direction in the 3, 7, 11, and 15th columns in the x direction are irradiated.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 8, the reference region 33 adjacent in the x direction (for example, the thirteenth reference region 33) is similarly changed from the pixel 36 at the lowest stage in the y direction at a position shifted by one pixel in the x direction. In addition, 16 shots are performed. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference region 33 (for example, the 14th reference region 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 15th reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 16th reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. With this operation, among the 16 × 16 pixels 36 in each reference region 33, all the 16 pixels in the y direction in the x direction 4, 8, 12, and 16 columns are irradiated.

  As described above, 16 shots are performed for each of the four adjacent reference regions 33 while shifting by one pixel in the y direction. This cycle is repeated four times while shifting by one pixel in the x direction. By performing a series of drawing operations for the set of 16 reference regions 33, it is possible to perform drawing without causing overlap in shot drawing positions within the reference region 33.

  As described above, in the example of FIG. 8, even if any of the multi-beams 20 is a defect beam, out of 16 × 16 pixels in the reference region 33, a pixel irradiated with the defect beam is set to a predetermined value. Can be separated. At least adjacent pixels can be prevented from being irradiated with a defect beam.

  Using this drawing sequence, the drawing process proceeds.

  As the pattern density map creation step, the pattern density ρ calculation unit 53 reads the drawing data from the storage device 140 and calculates the pattern density ρ in the pixel 36 for each pixel 36. Then, a pattern density map in which the pattern density ρ is defined as a map value is created using the pixels 36 as map elements.

  As the correction irradiation coefficient Dp (x) calculation step, the correction irradiation coefficient Dp (x) calculation unit 54 calculates a correction irradiation coefficient Dp for correcting the influence of the proximity effect and the like. With respect to the corrected irradiation coefficient Dp, the drawing region (here, for example, the stripe region 32) is virtually divided into a plurality of adjacent mesh regions (mesh regions for proximity effect correction calculation) in a mesh shape with a predetermined size. The size of the proximity mesh region is preferably set to about 1/10 of the influence range of the proximity effect, for example, about 1 μm. Then, the drawing data is read from the storage device 140, and the pattern area density ρ ′ of the pattern arranged in the adjacent mesh region is calculated for each adjacent mesh region.

  Next, the proximity effect correction irradiation coefficient Dp for correcting the proximity effect is calculated for each proximity mesh region. Here, the size of the mesh region for calculating the proximity effect correction irradiation coefficient Dp does not have to be the same as the size of the mesh region for calculating the pattern area density ρ ′. Further, the correction model of the proximity effect correction irradiation coefficient Dp and the calculation method thereof may be the same as the method used in the conventional single beam drawing method.

  As the incident irradiation amount D (x) calculation step, the incident irradiation amount D (x) calculation unit 56 calculates the incident irradiation amount D (x) for irradiating the pixel 36 for each pixel (drawing target pixel) 36. To do. The incident dose D (x) may be calculated as, for example, a value obtained by multiplying a preset reference dose Dbase by the proximity effect correction dose coefficient Dp and the pattern area density ρ. Thus, it is preferable to obtain the dose D in proportion to the area density of the pattern calculated for each pixel 36.

  As the irradiation time t calculation step, the irradiation time t calculation unit 58 calculates the irradiation time t of the electron beam for making the incident irradiation amount D (x) calculated for the pixel 36 incident on each pixel 36. The irradiation time t can be calculated by dividing the incident dose D (x) by the current density J. Then, an irradiation time t map that defines the irradiation time t obtained for each pixel 36 is created.

  As the settling time ts calculation step, the settling time calculation unit 52 calculates the settling time necessary for the irradiation setting position operation for each beam. The settling time is set to the shortest of the drawing position movement by the sub-deflection and the drawing position by the main deflection.

  As a drawing process, first, under the control of the drawing control unit 60, the deflection control circuit 130 divides the drawing area of the sample 101, and a plurality of pixels 36 (small areas) serving as the minimum irradiation area per beam of the multi-beam 20. The deflector 208 is controlled so that the deflector 208 collectively deflects the multi-beams 20 so that the adjacent pixels 36) are not irradiated with the beams that have passed through the same hole 22 of the plurality of holes 22. Specifically, it operates as follows. The deflection control circuit 130 (deflection control unit) controls the irradiation amount (irradiation time) calculated by each control circuit 41 of the blanking aperture array mechanism 204 in the shot order of the multi-beams 20 in accordance with the drawing sequence described above. Is output. Further, the deflection control circuit 130 outputs a control signal indicating a deflection amount for deflecting the multi-beam 20 to the desired irradiation region 34 to the DAC amplifier unit 132 in the shot order of the multi-beam 20. The DAC amplifier unit 132 converts the digital signal into an analog signal and applies the deflector 208 as a deflection voltage. Then, the drawing mechanism 150 divides the drawing area of the sample 101 in accordance with the drawing sequence described above, and the adjacent pixels 36 of the plurality of pixels 36 serving as the minimum irradiation unit area per multi-beam are a plurality of holes. A plurality of pixels 36 are drawn using the multi-beam 20 so that the beam that has passed through the same 22 holes 22 is not irradiated. The operation of the drawing mechanism 150 in the drawing apparatus 100 will be specifically described.

  The electron beam 200 emitted from the electron gun 201 (emission source) illuminates the entire shaped aperture array substrate 203 almost vertically by the illumination lens 202. A plurality of rectangular holes (openings) are formed in the shaped aperture array substrate 203, and the electron beam 200 illuminates a region including all of the plurality of holes. Each part of the electron beam 200 irradiated to the positions of the plurality of holes passes through the plurality of holes of the shaped aperture array substrate 203, for example, so that a plurality of rectangular electron beams (multi-beams) 20a to 20e, for example. Is formed. The multi-beams 20a to 20e pass through the corresponding blankers (first deflector: individual blanking mechanism) of the blanking aperture array mechanism 204, respectively. Each of these blankers deflects the electron beam 20 that individually passes (performs blanking deflection).

  The multi-beams 20 a to 20 e that have passed through the blanking aperture array mechanism 204 are reduced by the reduction lens 205 and travel toward a central hole formed in the limiting aperture substrate 206. Then, the multibeam 20 forms a crossover on the limiting aperture substrate 206. Here, the electron beam 20 deflected by the blanker of the blanking aperture array mechanism 204 deviates from the center hole of the limiting aperture substrate 206 and is blocked by the limiting aperture substrate 206. On the other hand, the electron beam 20 that has not been deflected by the blanker of the blanking aperture array mechanism 204 passes through the hole at the center of the limiting aperture substrate 206 as shown in FIG. Blanking control is performed by ON / OFF of the individual blanking mechanism, and ON / OFF of the beam is controlled. In this way, the limiting aperture substrate 206 blocks each beam deflected so as to be in the beam OFF state by the individual blanking mechanism. Then, for each beam, one shot beam is formed by the beam that has passed through the limiting aperture substrate 206 formed from when the beam is turned on to when the beam is turned off.

  The multi-beam 20 that has passed through the limiting aperture substrate 206 in a beam ON state by blanking control is focused by the objective lens 207 to become a pattern image with a desired reduction ratio, and has passed through the limiting aperture substrate 206 by the deflector 208. Each beam (the entire multi-beam 20) is deflected collectively in the same direction, and irradiated to each irradiation position on the sample 101 of each beam. In the example of FIG. 8, the deflector 208 deflects each shot so as to move to the adjacent shot reference region 33. The multi-beams 20 irradiated at a time are ideally arranged at a pitch obtained by multiplying the arrangement pitch of a plurality of holes of the shaped aperture array substrate 203 by the desired reduction ratio.

  In the first embodiment, as illustrated in the example of FIG. 8, drawing is performed so that adjacent pixels 36 are not irradiated by the beam that has passed through the same hole 22 of the shaped aperture array substrate 203. As a result, adjacent pixels 36 are made possible by beams that have passed through different blanking mechanisms 47 of the blanking aperture array mechanism 204. In this way, the pixels 36 irradiated with the beam that has passed through the same hole 22 of the shaped aperture array substrate 203 are dispersed. As a result, even if a defect beam occurs in the multi-beam 20, adjacent pixels 36 can be prevented from being irradiated by the defect beam. However, more desirably, as shown in the example of FIG. 8, the drawing sequence may be set so that the distance between the pixels 36 irradiated by the defect beam is greatly separated even when the defect beam is generated.

  FIG. 10 is a diagram illustrating an example of a calculation result of a dose profile in the absence of a defective beam in the comparative example of the first embodiment. In the example of FIG. 10A, for example, a line pattern having a line width of 100 nm is multiplexed and drawn in four passes with a beam having a width of 10 nm. At this time, all the beams are sequentially irradiated with a single beam in the reference region 33. Further, in multiple drawing, the same pixel is drawn for each pass while shifting the irradiation position so that the beam that has passed through the same individual blanking mechanism 47 is not irradiated. The example of FIG. 10A is a calculation example in the case where there is no bright spot / dark spot defect beam, so the line width is formed constant. On the other hand, the example of FIG. 10B shows a case where a defect beam of a dark spot exists in a part in the longitudinal direction of a line pattern having a line width of 100 nm. Similarly, for example, a case where a line pattern having a line width of 100 nm is multiplexed and drawn by four passes with a beam having a width of 10 nm is shown. Similarly, each beam irradiates the entire reference region 33 with one beam in order. Similarly, in multiple drawing, the same pixel is drawn for each pass while shifting the irradiation position so that the beam that has passed through the same individual blanking mechanism 47 is not irradiated. In the example of FIG. 10B, the dose amount of each pixel in the reference region 33 irradiated with the defect beam is smaller than that of each pixel in the reference region 33 irradiated with the healthy beam. It has become. For this reason, the line width to be formed becomes narrower as the dose decreases.

  FIG. 11 is a diagram illustrating an example of a calculation result of a dose profile in the first embodiment. In the example of FIG. 11, as shown in FIG. 8, the multi-beam 20 including the defect beam similar to the defect beam of FIG. In this example, a line pattern having a line width of 100 nm, for example, is multiplexed and drawn in four passes with a beam having a width of 10 nm, for example, while limiting pixels that irradiate within one reference region 33. As shown in FIG. 11, in the first embodiment, since the pixels irradiated with the defect beam are dispersed, the influence of the defect beam can be reduced, and the narrowing of the formed line width can be avoided or greatly reduced. Therefore, even if a new defective beam is generated during the drawing process, the influence on the dimension of the pattern to be formed can be avoided or greatly reduced.

  In the above-described example, a case where a plurality of reference areas 33 (for example, 16 shot reference areas 33) in the same set are arranged in a row in the x direction and arranged in a 16 × 1 arrangement in the x and y directions. Although explained, it is not limited to this. They may be arranged in an 8 × 2 array in the x and y directions. Alternatively, they may be arranged in a 4 × 4 array. Alternatively, they may be arranged in a 2 × 8 array. Alternatively, they may be arranged in a 1 × 16 array.

  As described above, according to the first embodiment, it is possible to reduce the influence of a defect beam in multi-beam writing regardless of a defect beam that may occur during writing. Therefore, a highly accurate pattern can be drawn.

Embodiment 2. FIG.
In the first embodiment, the case where the pixel group that irradiates the same reference region 33 is a pixel group arranged in a matrix parallel to the x and y directions has been described. However, the present invention is not limited to this. In Embodiment 2, a case where a pixel group having a different arrangement is irradiated will be described. The configuration of the drawing apparatus 100 is the same as that shown in FIG. The contents other than those described in particular are the same as those in the first embodiment.

  FIG. 12 is a diagram illustrating another example of the drawing sequence according to the second embodiment. The example of FIG. 12 shows a case where four y-direction columns of the 4 × 4 pixel 36 group that irradiates each reference region 33 are formed by shifting one pixel at a time in the y-direction toward the x-direction. . Thus, among the plurality of pixels 36 in which the drawing region 30 (or stripe region 32) of the sample 101 is divided, the pixel group 36 (small region group) irradiated with the beam that has passed through the same hole 22 is in the x direction. The pixels 36 adjacent in the (first direction) are set to be shifted in the y direction (second direction) orthogonal to the x direction.

  In the example of FIG. 12, each reference region 33 is irradiated with 4 × 4 pixels 36 that apparently have a parallelogram shape by a beam that has passed through the same hole 22.

  In the example of FIG. 12, in the first shot, each beam of the multi-beam 20 irradiates the pixel 36 at the lowest stage in the y direction in the first row in the x direction from the left of the target reference region 33. In the second shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the fifth row from the bottom in the y direction. In the third shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the ninth row from the bottom in the y direction. In the fourth shot, each beam of the multi-beam 20 irradiates the 13th pixel 36 in the first row from the left and the 13th row from the bottom in the y direction of the same reference region 33 from the left. With the four shots from the first time to the fourth time, each reference region 33 is irradiated with 4 pixels at a 4 pixel pitch among the 16 pixels in the first column in the x direction.

  In the fifth shot, each beam of the multi-beam 20 irradiates the second pixel 36 in the fifth row in the x direction and the y direction from the left of the target reference region 33. In the sixth shot, each beam of the multi-beam 20 irradiates the pixels 36 in the sixth row from the bottom in the fifth row in the x direction and the y direction from the left of the target reference region 33. In the seventh shot, each beam of the multi-beam 20 irradiates the pixels 36 in the fifth row from the left of the target reference region 33 in the x direction and the tenth pixel from the bottom in the y direction. In the eighth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the fifth row from the left of the target reference region 33 in the x direction and the 14th pixel from the bottom in the y direction.

  In the ninth shot, each beam of the multi-beam 20 irradiates the third row of pixels 36 in the ninth row and the y direction in the x direction from the left of the same reference region 33. In the tenth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the ninth row from the left in the x direction and the seventh pixel from the bottom in the y direction of the same reference region 33. In the eleventh shot, each beam of the multi-beam 20 irradiates the ninth row of pixels 36 in the x direction from the left and the eleventh row from the bottom in the y direction of the same reference region 33. In the twelfth shot, each beam of the multi-beam 20 irradiates the 15th pixel 36 in the ninth row from the left in the x direction and the fifteenth row from the bottom in the y direction of the same reference region 33.

  In the 13th shot, each beam of the multi-beam 20 irradiates the fourth row of pixels 36 in the 13th row in the x direction and the y direction from the left of the same reference region 33. In the 14th shot, each beam of the multi-beam 20 irradiates the 13th column in the x direction from the left of the same reference region 33 and the eighth stage pixel 36 from the bottom in the y direction. In the fifteenth shot, each beam of the multi-beam 20 irradiates the thirteenth column 36 in the x direction from the left of the same reference region 33 and the twelfth pixel 36 in the y direction from the bottom. In the 16th shot, each beam of the multi-beam 20 irradiates the 13th column from the left of the same reference region 33 to the 13th column in the x direction and the 16th pixel from the bottom in the y direction.

  As described above, with 16 shots, 16 × 16 pixels 36 in the same reference region 33 pass 4 × 4 (= 16) pixels at the same pixel pitch through the same individual blanking mechanism 47 (same The beam that has passed through the hole 22 is irradiated. Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 8, 16 shots are similarly performed at a position shifted by one pixel in the y direction with respect to a reference area 33 (for example, the second reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the third reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the fourth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. As a result of this operation, among the 16 × 16 pixels 36 in each reference region 33, all the 16 pixels in the y direction that are sequentially shifted one pixel at a time in the y direction in the x direction 1, 5, 9, and 13 columns are irradiated. Will be.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 12, with respect to a reference region 33 adjacent in the x direction (for example, the fifth reference region 33), a position shifted by one pixel in the x direction is similarly applied from the pixel 36 at the lowest stage in the y direction. , Perform 16 shots. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference area 33 (for example, the sixth reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the seventh reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the eighth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. By this operation, all 16 pixels in the y direction which are sequentially shifted one pixel at a time in the y direction in the x direction 2, 6, 10, 14th column among the 16 × 16 pixels 36 in each reference region 33 are irradiated. Will be.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 12, the reference region 33 adjacent in the x direction (for example, the ninth reference region 33) is similarly changed from the pixel 36 at the lowest stage in the y direction at a position shifted by one pixel in the x direction. In addition, 16 shots are performed. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference region 33 (for example, the tenth reference region 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 11th reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the twelfth reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. By this operation, all 16 pixels in the y direction which are sequentially shifted one pixel at a time in the y direction in the x direction 3, 7, 11, and 15 columns among the 16 × 16 pixels 36 in each reference region 33 are irradiated. Will be.

  Subsequently, the irradiation target of the beam that has passed through the same hole 22 moves to the reference region 33 adjacent in the x direction. As shown in FIG. 12, the reference region 33 adjacent in the x direction (for example, the thirteenth reference region 33) is similarly changed from the pixel 36 at the lowest stage in the y direction at a position shifted by one pixel in the x direction. In addition, 16 shots are performed. Subsequently, similarly, 16 shots are performed at a position shifted by one pixel in the y direction with respect to the reference region 33 (for example, the 14th reference region 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 15th reference area 33) adjacent in the x direction. Subsequently, 16 shots are similarly performed at positions shifted by one pixel in the y direction with respect to the reference area 33 (for example, the 16th reference area 33) adjacent in the x direction. The same operation is performed for the other beams of the multi-beam 20. By this operation, all 16 pixels in the y direction, which are sequentially shifted one pixel at a time in the y direction in the x direction 4, 8, 12, and 16 columns, among the 16 × 16 pixels 36 in each reference region 33 are irradiated. Will be.

  As described above, 16 shots are performed for each of the four adjacent reference regions 33 while shifting by one pixel in the y direction. This cycle is repeated four times while shifting by one pixel in the x direction. Even when the reference region 33 is irradiated with 4 × 4 pixels 36 having an apparent parallelogram shape by the beam that has passed through the same hole 22 by a series of drawing on the set of 16 reference regions 33. In the reference area 33, drawing can be performed without duplication of shot drawing positions.

  As described above, as shown in the example of FIG. 12, when the reference regions 33 are irradiated with the 4 × 4 pixels 36 having an apparent parallelogram shape by the beams that have passed through the same hole 22, the multi-beam 20. Even if any of these beams is a defective beam, the pixels irradiated with the defective beam among the 16 × 16 pixels in the reference region 33 can be separated by a predetermined distance. At least adjacent pixels can be prevented from being irradiated with a defect beam.

  FIG. 13 is a diagram illustrating another example of the calculation result of the dose profile in the second embodiment. In the example of FIG. 13, 4 × 4 arrayed in the shape of the parallelogram shown in FIG. 12 in each reference region 33 using the multi-beam 20 including the defect beam similar to the defect beam of FIG. In the case where the pixel 36 is drawn by a beam that has passed through the same hole 22, for example, a line pattern having a line width of 100 nm is multiplexed and drawn in four passes with a beam having a width of 10 nm. As shown in FIG. 13, in the second embodiment, since the pixels irradiated with the defect beam are dispersed, the influence of the defect beam can be reduced, and the narrowing of the formed line width can be avoided or greatly reduced. Therefore, even if a new defective beam is generated during the drawing process, the influence on the dimension of the pattern to be formed can be avoided or greatly reduced.

  As described above, according to the second embodiment, the positions of the pixels 36 irradiated with the defect beam can be dispersed even when the arrangement of the pixel groups in the reference region 33 irradiated with the beam that has passed through the same hole 22 is different. Similar to the first embodiment, the influence of a defect beam in multi-beam writing can be reduced regardless of a defect beam that may occur during writing. Therefore, a highly accurate pattern can be drawn.

Embodiment 3 FIG.
In each of the above-described embodiments, the case has been described in which the rectangular reference region 33 including, for example, 16 × 16 pixels 36 is set in parallel to the x and y directions. In the third embodiment, a configuration for setting a reference region 33 having a shape different from that of the second embodiment will be described. The configuration of the drawing apparatus 100 is the same as that shown in FIG. The contents other than those described in particular are the same as those in the second embodiment.

  FIG. 14 is a diagram illustrating an example of the reference region 33 in the third embodiment. In the third embodiment, as in the second embodiment, among a plurality of pixels 36 in which the drawing region 30 (or stripe region 32) is divided, a group of pixels 36 (small regions) irradiated with a beam that has passed through the same hole 22 The group) is set by shifting the pixels 36 adjacent in the x direction (first direction) in the y direction (second direction) orthogonal to the x direction. In the third embodiment, the reference region 33 is set according to such an arrangement. In the arrangement of the pixel groups in the reference region 33 in the third embodiment, each column composed of the group of pixels 36 arranged in the y direction is a set of four columns in the x direction, and each set is in the y direction. Are formed one pixel at a time.

  In the third embodiment, the reference region setting unit 51 is shifted by one pixel in the y direction by 4 × 16 pixel groups in the x and y directions in accordance with the 4 × 4 pixels 28 having a parallelogram shape. Four 4 × 16 pixel groups arranged in the x direction are set as the reference region 33.

  In the third embodiment, by setting the reference region 33 as described above, the entire reference region 33 can be irradiated by performing a drawing sequence similar to that in the second embodiment.

  As described above, according to the third embodiment, the positions of the pixels 36 irradiated with the defect beam can be dispersed even when the pixel arrangement of the reference region 33 is different. Similar to the first embodiment, the influence of a defect beam in multi-beam writing can be reduced regardless of a defect beam that may occur during writing. Therefore, a highly accurate pattern can be drawn.

Embodiment 4 FIG.
In each of the above-described embodiments, the case has been described in which a plurality of pixels 36 are divided in a grid pattern by grid lines parallel to the x and y directions. In the fourth embodiment, a configuration in which the pixel array is set to an array having a different shape from the above-described embodiments will be described. The configuration of the drawing apparatus 100 is the same as that shown in FIG. The contents other than those described in particular are the same as those in the first embodiment.

  FIG. 15 is a diagram illustrating an example of a pixel arrangement in the fourth embodiment and a comparative example. FIG. 15 shows 16 shot target pixels when the fifth reference region 33 in the drawing sequence shown in FIG. 8 is drawn. FIG. 15A shows a plurality of pixels 36 arranged by pixel division in the first embodiment as a comparative example. In contrast, the pixel dividing unit 50 according to the fourth embodiment divides the stripe region 32 so that pixels adjacent in the x direction are arranged while being shifted by a ½ pixel size in the y direction.

  The reference area setting unit 51 sets four 4 × 16 pixel groups arranged in the x direction as a reference area 33 by arranging 4 × 16 pixel groups in the x and y directions, which are arranged while being shifted by ½ pixel size in the y direction. Set as.

  In the example of FIG. 15, when the fifth reference region 33 in the drawing sequence shown in FIG. 8 is drawn, the positions in the x direction 2, 6, 10, 14th column shifted by one pixel in the x direction are shown. Even when the lowermost pixel 36 in the y direction is selected, the lowermost pixel 36 in the x direction 2, 6, 10, 14 is compared with the lowermost pixel 36 in the x direction 1, 5, 9, 13th column. Thus, the position is shifted by 1/2 pixel size in the y direction. Thus, it is preferable even when pixel division and reference region setting are performed.

  FIG. 16 is a diagram illustrating an example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and the comparative example. In the example of FIG. 16, a rectangular or substantially rectangular reference area 33 is set in each case.

  FIG. 16A shows a drawing sequence when the pixel 36 is irradiated by the same method as the drawing sequence shown in FIG. 8 (without shifting in the Y direction). FIG. 16B shows a case where the fifth, ninth, and thirteenth reference regions 33 in the drawing sequence shown in FIG. 8 are drawn while being shifted in the y direction by 1/2 pixel size (Y direction). The drawing sequence of (half grid shift) is shown. FIG. 16C shows a case where the fifth, ninth, and thirteenth reference regions 33 in the drawing sequence shown in FIG. 8 are drawn with irradiation shifted in the y direction by one pixel size (one grid in the Y direction). Shows a drawing sequence.

  In the example of FIG. 16C, the pixel dividing unit 50 defines a plurality of pixels 36 by dividing the stripe region 32 in a grid pattern by grid lines parallel to the x and y directions. On the other hand, the reference area setting unit 51 uses four 4 × 16 pixel groups arranged in the x direction as a reference, with a group of 4 × 16 pixels arranged in the x and y directions arranged while being shifted by ½ pixel size in the y direction. Set as area 33.

  As described above, when the rectangular or substantially rectangular reference area 33 is set by changing the pixel dividing method or the reference area 33 setting method, it is also preferable to change the y-direction shift amount.

  FIG. 17 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and the comparative example. In the example of FIG. 17, the reference area 33 is set to be a parallelogram or a substantially parallelogram.

  FIG. 17A shows a drawing sequence when the pixel 36 is irradiated by the same method as the drawing sequence shown in FIG. FIG. 17B shows a drawing sequence in the case where the fifth, ninth, and thirteenth reference regions 33 in the drawing sequence shown in FIG. Indicates.

  In the example of FIG. 17A, the pixel dividing unit 50 defines a plurality of pixels 36 by dividing the stripe region 32 in a grid pattern by grid lines parallel to the x and y directions. On the other hand, the reference area setting unit 51 sets 4 × 16 pixel groups in the x and y directions as a group, and sets four 4 × 16 pixel groups arranged in the x direction, which are shifted in the y direction by one pixel, as the reference area 33. .

  In the example of FIG. 17B, the pixel dividing unit 50 divides the stripe region 32 so that pixels adjacent in the x direction are arranged while being shifted by ½ pixel size in the y direction. Then, the reference area setting unit 51 sets the x × 4 pixel group in the x direction and the x direction, which are arranged while being shifted by ½ pixel size in the y direction, and is arranged in the x direction shifted in the y direction by one pixel. Four 4 × 16 pixel groups are set as the reference region 33.

  As described above, when setting the reference region 33 having an apparent parallelogram shape by changing the method of dividing pixels or setting the reference region 33, it is preferable to change the y-direction shift amount. It is.

  FIG. 18 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and the comparative example. In the example of FIG. 18A, a case where four y-direction columns of the 4 × 4 pixel group 36 that irradiates each reference region 33 are formed by shifting two pixels toward the x-direction in the y-direction. Show. In the example of FIG. 18A, the pixel dividing unit 50 defines a plurality of pixels 36 by dividing the stripe region 32 in a grid pattern by grid lines parallel to the x and y directions. On the other hand, the reference region setting unit 51 sets 4 × 16 pixel groups in the x and y directions as a set, and sets four 4 × 16 pixel groups arranged in the x direction that are shifted in the y direction by two pixels as the reference region 33. .

  In the example of FIG. 18B, a case where four y-direction columns of 4 × 4 pixel 36 groups that irradiate each reference region 33 are formed by shifting one pixel at a time in the y-direction toward the x-direction. Show. However, the pixel dividing unit 50 divides the stripe region 32 so that pixels adjacent in the x direction are arranged while being shifted by a ½ pixel size in the y direction. Then, the reference area setting unit 51 arranges the 4 × 16 pixel groups in the x and y directions, which are arranged while being shifted by ½ pixel size in the y direction, and arranges them in the x direction shifted in the y direction by 2 pixels. Four 4 × 16 pixel groups are set as the reference region 33.

  As described above, it is also preferable to set the reference region 33 having a parallelogram shape in which the angle of the oblique side is further increased.

  FIG. 19 is a diagram illustrating another example of a drawing sequence having different y-direction shift amounts in the fourth embodiment and the comparative example. In the example of FIG. 19, a case where four y-direction columns of 4 × 4 pixel 36 groups that irradiate each reference region 33 are formed by staggering two pixels toward the x-direction in the y-direction. Show. In the example of FIG. 19A, the pixel dividing unit 50 defines a plurality of pixels 36 by dividing the stripe region 32 in a grid pattern by grid lines parallel to the x and y directions. On the other hand, the reference area setting unit 51 sets a group of 4 × 16 pixels in the x and y directions, and sets four 4 × 16 pixel groups arranged in the x direction that are alternately shifted in the y direction by two pixels as the reference area 33. Set.

  In the example of FIG. 19B, a case where four y-direction columns of 4 × 4 pixel 36 groups that irradiate each reference region 33 are formed by shifting one pixel at a time in the y-direction toward the x-direction. Show. However, the pixel dividing unit 50 divides the stripe region 32 so that pixels adjacent in the x direction are arranged while being shifted by a ½ pixel size in the y direction. Then, the reference region setting unit 51 sets the 4 × 16 pixel group in the x and y directions to be arranged while being shifted by ½ pixel size in the y direction, and the x direction is alternately shifted in the y direction by two pixels. A group of four 4 × 16 pixels arranged in a row is set as the reference region 33.

  As described above, it is also preferable to set the reference region 33 that is apparently a combined shape of two parallelograms.

  As described above, according to the fourth embodiment, the present invention can be applied not only when the pixels 36 are arranged two-dimensionally parallel to the x and y directions, but also when the pixels 36 are shifted by a size smaller than the pixel size. The reference region 33 is not limited to a rectangular shape parallel to the x and y directions, and may be set to a parallelogram shape whose position is shifted in the y direction, for example. Further, according to the fourth embodiment, the positions of the pixels 36 irradiated with the defect beam in the reference region 33 can be dispersed. Similar to the first embodiment, the influence of a defect beam in multi-beam writing can be reduced regardless of a defect beam that may occur during writing. Therefore, a highly accurate pattern can be drawn.

Embodiment 5. FIG.
In each of the above-described embodiments, a case is shown in which each beam of the multi-beam 20 moves to the next adjacent reference region 33 after irradiating 4 × 4 pixels in the reference region 33 that is in charge of it. It is not a thing.

  FIG. 20 is a diagram illustrating an example of a drawing sequence according to the fifth embodiment. In the example of FIG. 20, a set of reference regions 33 arranged in 8 × 2 columns in the x and y directions is shown. In the example of FIG. 20A, for the pixel group in the x-direction 1, 5, 9, and 13th columns, the reference region 33 in charge of the pixels in the y-direction 1, 5, 9, and 13th rows is shown in the lower left. . The reference area 33 in charge of the pixels in the second, sixth, tenth and fourteenth stages in the y direction is shown in the upper left. In the lower right, a reference area 33 in charge of the pixels in the third, seventh, eleventh and fifteenth stages in the y direction is shown. The reference area 33 in charge of the pixels in the fourth, eighth, twelfth and sixteenth stages in the y direction is shown in the upper right. In this example, four groups of 2 × 2 reference regions 33 in which the assigned pixels are shifted one by one are arranged in the x direction.

  In the example of FIG. 20A, in the first shot, each beam of the multi-beam 20 irradiates the pixel 36 at the lowest stage in the first column in the x direction from the left of the target reference region 33 in the x direction. . In the second shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the fifth row from the bottom in the y direction. In the third shot, each beam of the multi-beam 20 irradiates the first row of pixels 36 in the x direction from the left of the same reference region 33 and the ninth row from the bottom in the y direction. In the fourth shot, each beam of the multi-beam 20 irradiates the 13th pixel 36 in the first row from the left and the 13th row from the bottom in the y direction of the same reference region 33 from the left. With the four shots from the first time to the fourth time, each reference region 33 is irradiated with 4 pixels at a 4 pixel pitch among the 16 pixels in the first column in the x direction.

  Subsequently, as shown in FIG. 20A, the reference region 33 adjacent in the y direction (for example, the second reference region 33) is similarly subjected to four times at a position shifted by one pixel in the y direction. A shot (1st to 4th shots for the second reference region 33) is performed.

  Subsequently, as shown in FIG. 20A, the original reference area 33 (for example, the first reference area 33) adjacent in the −y direction is moved to 5 in the x direction from the left in the fifth shot. The lowermost pixel 36 is irradiated in the y direction in the column. In the sixth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the fifth row from the left in the x direction and the fifth row from the bottom in the y direction from the left of the target reference region 33. In the seventh shot, each beam of the multi-beam 20 irradiates the pixel 36 in the fifth row from the left of the target reference region 33 in the x direction and the ninth row from the bottom in the y direction. In the eighth shot, each beam of the multi-beam 20 irradiates the pixels 36 in the fifth row from the left of the target reference region 33 in the x direction and the thirteenth pixel from the bottom in the y direction.

  Subsequently, as shown in FIG. 20A, the reference region 33 adjacent in the y direction (for example, the second reference region 33) is similarly subjected to four times at a position shifted by one pixel in the y direction. A shot (5th to 8th shots for the second reference region 33) is performed.

  Subsequently, as shown in FIG. 20A, the image moves to the original reference region 33 (for example, the first reference region 33) adjacent in the −y direction, and 9 in the x direction from the left in the ninth shot. The lowermost pixel 36 is irradiated in the y direction in the column. In the tenth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the ninth row from the left and the fifth row from the bottom in the y direction from the left of the target reference region 33. In the eleventh shot, each beam of the multi-beam 20 irradiates the pixel 36 in the ninth row from the left in the x direction and the ninth row from the bottom in the y direction from the left of the target reference region 33. In the twelfth shot, each beam of the multi-beam 20 irradiates the thirteenth pixel 36 in the ninth row from the left in the x direction and the thirteenth row in the y direction from the left of the target reference region 33.

  Subsequently, as shown in FIG. 20A, the reference region 33 adjacent in the y direction (for example, the second reference region 33) is similarly subjected to four times at a position shifted by one pixel in the y direction. A shot (9th to 12th shots for the second reference region 33) is performed.

  Subsequently, as illustrated in FIG. 20A, the original reference area 33 (for example, the first reference area 33) adjacent in the −y direction is moved to 13 in the x direction from the left in the 13th shot. The lowermost pixel 36 is irradiated in the y direction in the column. In the fourteenth shot, each beam of the multi-beam 20 irradiates the pixel 36 in the 13th row from the left of the target reference region 33 in the x direction and the fifth row from the bottom in the y direction. In the fifteenth shot, each beam of the multi-beam 20 irradiates the thirteenth row of pixels 36 in the 13th row from the left in the x direction and the 9th row from the bottom in the y direction of the target reference region 33. In the sixteenth shot, each beam of the multi-beam 20 irradiates the thirteenth row of pixels 36 in the 13th row from the left of the target reference region 33 in the x direction and the 13th row from the bottom in the y direction.

  Subsequently, as shown in FIG. 20A, the reference region 33 adjacent in the y direction (for example, the second reference region 33) is similarly subjected to four times at a position shifted by one pixel in the y direction. A shot (13th to 16th shots for the second reference region 33) is performed.

  Next, as shown in FIG. 20A, the target pixels are shot in order by combining the third and fourth reference regions 33 adjacent in the x direction in the y direction.

  As described above, for example, the shot order may be set by combining a plurality of reference regions 33 arranged in the y direction. In addition, the shot order is not always performed from the bottom to the top (y direction), but the shot direction may be changed from the bottom to the top (y direction) and the return path from the top to the bottom (−y direction).

  The example of FIG. 20B shows an 8 × 2 arrangement example in which the set of 16 reference regions 33 described in FIG. 12 is arranged in two stages in the y direction. In such a case, the shot order may be set by combining a plurality of reference regions 33 arranged in the y direction.

  FIG. 21 is a diagram showing another example of the drawing sequence in the fifth embodiment. In the example of FIG. 21, the reference area 33 for 4 × 4 pixel shot is divided into two reference areas 33 for 2 × 4 pixel shot. In the example of FIG. 21A, in the drawing sequence shown in FIG. 8, the reference region 33 in charge of the pixel group in the first and ninth columns in the x direction and the reference region in charge of the pixel group in the fifth and thirteenth columns in the x direction. A case is shown in which 16 reference regions 33 are arranged in two rows in the y direction and 16 shot regions are arranged one by one in the x direction while shifting the shot responsible pixels. In the example of FIG. 21B, in the drawing sequence shown in FIG. 8, the reference region 33 in charge of the pixel group in the first and fifth columns in the x direction and the reference region in charge of the pixel group in the ninth and thirteenth columns in the x direction. A case is shown in which 16 reference regions 33 are arranged in two rows in the y direction and 16 shot regions are arranged one by one in the x direction while shifting the shot responsible pixels. Illustration of five or more reference regions 33 in the x direction is omitted.

  FIG. 22 is a diagram showing another example of the drawing sequence in the fifth embodiment. In the example of FIG. 22, the reference region 33 for 4 × 4 pixel shot is divided into two reference regions 33 for 2 × 4 pixel shot. In the example of FIG. 22A, in the drawing sequence shown in FIG. 12, the reference region 33 responsible for the pixel group in the first and ninth columns in the x direction and the reference region responsible for the pixel group in the fifth and thirteenth columns in the x direction. A case is shown in which 16 reference regions 33 are arranged in two rows in the y direction and 16 shot regions are arranged one by one in the x direction while shifting the shot responsible pixels. In the example of FIG. 22B, in the drawing sequence shown in FIG. 12, the reference region 33 responsible for the pixel group in the first and fifth columns in the x direction and the reference region responsible for the pixel group in the ninth and thirteenth columns in the x direction. A case is shown in which 16 reference regions 33 are arranged in two rows in the y direction and 16 shot regions are arranged one by one in the x direction while shifting the shot responsible pixels. Illustration of five or more reference regions 33 in the x direction is omitted.

  As described above, the number of shot pixels per reference area 33 may be reduced, and the number of reference areas 33 forming one set may be increased instead.

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. The drawing sequence is an example, and other drawing sequences may be used as long as the drawing sequences are not irradiated with the beams passing through the same hole 22 between the adjacent pixels 36. In the above-described example, the case where 16 × 16 pixels are set as the inter-beam pitch is shown, but the present invention is not limited to this. For example, the present invention can be applied even when 8 × 8 pixels are set as the inter-beam pitch or when 4 × 4 pixels are set as the inter-beam pitch. In other words, the present invention can be applied even when the reference region 33 is configured by 8 × 8 pixels or by 4 × 4 pixels. In any case, it is configured so that adjacent pixels are not irradiated with a beam passing through the same hole 22.

  Further, one set of M (for example, 16) reference regions 33 may be set to M in a row in the x direction, or may be set to two steps in the y direction and M / 2 in the x direction. . Alternatively, it may be set to four stages in the y direction and M / 4 pieces in the x direction.

  Further, in the above-described example, the case where a plurality of pixels 36 are irradiated with a beam passing through the same hole 22 per one reference region 33 is shown, but this is a case where one pixel is irradiated per one reference region 33. May be. In such a case, the drawing sequence may be set with the reference areas 33 corresponding to the number of pixels constituting the reference area 33 as a set of reference areas 33.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used. For example, although the description of the control unit configuration for controlling the drawing apparatus 100 is omitted, it goes without saying that the required control unit configuration is appropriately selected and used.

  In addition, all multi-charged particle beam writing methods and multi-charged particle beam writing apparatuses that include the elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

20 Multi beam 22 Hole 24 Control electrode 26 Counter electrode 25 Passing hole 28 Pixel 30 Drawing area 32 Stripe area 33 Reference area 34 Irradiation area 36 Pixel 50 Pixel division part 51 Reference area setting part 52 Settling time calculation part 53 ρ calculation part 54 Dp (X) computing unit 56 D (x) computing unit 58 t computing unit 60 drawing control unit 100 drawing apparatus 101 sample 102 electron column 103 drawing room 105 XY stage 110 control computer 112 memory 130 deflection control circuit 132 DAC amplifier unit 139 stage Position detector 140 Storage device 150 Drawing mechanism 160 Control system circuit 200 Electron beam 201 Electron gun 202 Illumination lens 203 Molding aperture array substrate 204 Blanking aperture array mechanism 205 Reduction lens 206 Limiting aperture substrate 207 Objective lens 208 Deflector 210 Mirror

Claims (5)

Forming a multi-beam by passing a part of the charged particle beam through each of the plurality of openings of the shaped aperture array substrate in which the plurality of openings are formed;
The adjacent small areas of the plurality of small areas that are the minimum irradiation unit area per beam of the multi-beam divided from the drawing area of the sample are not irradiated with the beams that have passed through the same opening of the plurality of openings. Drawing the plurality of small regions using the multi-beam;
A multi-charged particle beam writing method comprising:   Among the plurality of small regions, the small region group irradiated with the beam that has passed through the same opening portion shifts the small regions adjacent to each other in the first direction in the second direction orthogonal to the first direction. The multi-charged particle beam writing method according to claim 1, wherein the method is set. The value m ₁ (the integer of m ₁ ≧ 2) of the total number of small areas in the first direction and the value m ₂ (m of the total number of small areas in the second direction) arranged at the inter-beam pitch of the multi-beam. ₂ ), which are composed of a group of small areas of m ₁ column × m ₂ columns, and the adjacent reference regions are in the same positional relationship with each other. 3. The multi-charged particle beam drawing method according to claim 1, wherein the plurality of reference regions are drawn while shifting an irradiation position so as not to be irradiated by the beam that has passed through the same opening.   The reciprocal number of the value obtained by dividing the number of small regions irradiated with the beam that has passed through the same opening portion by the total number of small regions in each reference region among the small region groups in each reference region of the plurality of reference regions. The plurality of reference areas are drawn while shifting the irradiation position so that the small areas having the same positional relationship between the reference areas of the same set are not irradiated by the beam that has passed through the same opening. The multi-charged particle beam writing method according to claim 3, wherein: A stage capable of continuous movement on which a sample coated with resist is placed;
An emission source that emits a charged particle beam;
A plurality of openings are formed, and a part of the charged particle beam passes through each of the plurality of openings to form a multi-beam aperture array substrate,
A blanking aperture array mechanism in which a plurality of blankers for performing blanking deflection of the corresponding beams among the multi-beams are disposed;
A limiting aperture substrate that blocks each beam deflected to be in a beam OFF state by the plurality of blankers;
A deflector for collectively deflecting the multi-beam;
The adjacent small areas of the plurality of small areas that are the minimum irradiation areas per beam of the multi-beams, which are divided from the drawing area of the sample, are not irradiated with the beams that have passed through the same openings of the plurality of openings. A deflection control circuit for controlling the deflector so that the deflector collectively deflects the multi-beams;
A multi-charged particle beam drawing apparatus comprising: