Charged particle beam drawing method and charged particle beam drawing apparatus

Abstract

To suppress variation in deflection voltage when switching deflection regions and to improve drawing accuracy.SOLUTION: In a charged particle beam drawing method according to the present embodiment, a drawing region of a substrate is divided into a plurality of deflection regions; a charged particle beam is sequentially deflected to reference positions of the plurality of deflection regions; the deflection region is divided into a plurality of small regions; the charged particle beam is sequentially deflected from the reference position of the deflection region to the reference positions of the plurality of small regions; and the charged particle beam is deflected from the reference position of the small region to a predetermined position within the small region to draw a pattern. A displacement in relative position between a small region in an (N-1)-th deflection region (N is an integer equal to or greater than 2) where pattern drawing is last performed and a small region in an N-th deflection region where the pattern drawing is first performed is within a predetermined threshold. The predetermined threshold is set on the basis of a previously obtained relationship between the relative position displacement and fluctuation in a drawing position.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a charged particle beam writing method and a charged particle beam writing apparatus. [Background technology]

[0002] As LSIs become more highly integrated, the circuit line width required for semiconductor devices is becoming finer every year. To form the desired circuit pattern on a semiconductor device, a method is adopted in which a high-precision original pattern (called a mask, or a reticle, especially when used in steppers and scanners) formed on quartz is reduced and transferred onto a wafer using a reduction projection exposure system. The high-precision original pattern is drawn using an electron beam drawing system, using so-called electron beam lithography technology.

[0003] Electron beam lithography systems irradiate a desired position with an electron beam using multiple stages of deflectors with different sizes of deflection areas to write a pattern. For example, an electron beam lithography system has been proposed that has three stages of deflectors: a main deflector, a sub-deflector, and a sub-sub-deflector. FIG. 2 is a conceptual diagram illustrating the deflection areas of each deflector. In FIG. 2, a writing area 10 on a substrate 101 to be written is virtually divided into a plurality of stripe regions 20 in the y direction, for example, by the deflection width of the main deflector. The regions obtained by dividing the stripe region 20 in the x direction by the deflection width of the main deflector are the deflection areas of the main deflector (main deflection areas).

[0004] This main deflection area is virtually divided into a plurality of sub-fields (SF) 30 in a mesh shape, with a deflection size of the sub-deflector. Each SF 30 is then virtually divided into a plurality of under-sub-fields (here, abbreviated as "TF" for Tertiary Deflection Field, meaning the third deflection; the same applies hereinafter) 40 in a mesh shape, with a deflection size of the sub-deflector.

[0005] A shot figure is written at each shot position 42 of each TF 40. In this way, the deflection areas of the three stages of deflectors that deflect the electron beam are the main deflection area, SF30, and TF40 in order of size from largest to smallest.

[0006] The main deflector deflects the electron beam to a reference position A of SF 30. The sub-deflector deflects the electron beam from the reference position A of SF 30 to a reference position B of TF 40. Then, the sub-sub-deflector deflects the electron beam from the reference position B of TF 40 to a shot position 42 of the beam to be irradiated within the TF 40.

[0007] The multiple TFs 40 in SF 30 are drawn in order according to a predetermined rule. For example, as shown in Figure 13, drawing proceeds in order from the bottom left TF 40 of SF 30_1 upward (+y direction). After drawing of the TFs 40 in the leftmost column is completed, drawing proceeds in order from the second column from the left downward (-y direction). Thereafter, drawing proceeds column by column in the same manner while switching the drawing direction.

[0008] When writing is completed for all TFs 40 in SF30_1, writing begins for the next SF30_2. At this time, the main deflector deflects the electron beam from the reference position A1 of SF30_1 to the reference position A2 of SF30_2. The sub-deflector also deflects the electron beam from the last TF 40 in the writing order to the first TF 40, starting writing from the bottom-left TF 40. The writing order of the TFs 40 is the same for SF30_1 and SF30_2. In the example shown in Figure 13, when writing begins for SF30_2, the sub-deflector deflects the electron beam from the top-right TF 40 to the bottom-left TF 40 in the SF. This results in a large deflection amount and a large change in the deflection voltage. The voltage applied to the sub-deflector is output from a DAC amplifier, and a settling time is required depending on the magnitude of the change in output voltage. Insufficient settling time causes an error in the deflection movement of the electron beam, reducing writing accuracy. On the other hand, if the settling time is too long, the throughput will decrease.

[0009] As described above, conventionally, when switching the deflection region for drawing a pattern, the change in deflection voltage becomes large, which causes a problem of degrading the drawing accuracy. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-055109 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-157742 [Patent Document 3] Japanese Patent Application Publication No. 05-299327 Summary of the Invention [Problem to be solved by the invention]

[0011] An object of the present invention is to provide a charged particle beam drawing apparatus and a charged particle beam drawing method that can suppress changes in deflection voltage when switching deflection regions and improve drawing accuracy. [Means for solving the problem]

[0012] A charged particle beam writing method according to one embodiment of the present invention is a charged particle beam writing method that uses a deflector to deflect a charged particle beam to write a pattern on a substrate, the method comprising: dividing a writing area on the substrate into a plurality of deflection areas; deflecting the charged particle beam sequentially to reference positions of the plurality of deflection areas; dividing the deflection area into a plurality of small areas; deflecting the charged particle beam from the reference position of the deflection area to reference positions of the plurality of small areas sequentially; deflecting the charged particle beam from the reference position of the small area to a predetermined position within the small area to write a pattern; and determining whether a displacement of a relative position in each deflection area between the small area in which the pattern is last written within the N-1th deflection area (N is an integer greater than or equal to 2) and the small area in which the pattern is first written within the Nth deflection area is within a predetermined threshold value, the predetermined threshold value being set based on a relationship between a predetermined relationship between the displacement of the relative position and fluctuation of the writing position.

[0013] A charged particle beam drawing apparatus according to one aspect of the present invention comprises an emitter that emits a charged particle beam, a deflector that adjusts the irradiation position of the charged particle beam on a substrate placed on a stage, and a control unit that controls the deflector, wherein the deflector has a first deflector that deflects the charged particle beam to a reference position of a plurality of deflection regions into which a drawing region of the substrate is divided so as to follow the movement of the stage, and a second deflector that deflects the charged particle beam from the reference position of each deflection region to a reference position of a plurality of small regions into which each deflection region is divided, and the control unit controls the deflector so that the displacement of the relative position in each deflection region between the small region in which a pattern is last drawn in the N-1th deflection region (N is an integer of 2 or more) and the small region in which a pattern is first drawn in the Nth deflection region is within a set predetermined threshold, and the predetermined threshold is set based on the relationship between the displacement of the relative position obtained in advance and fluctuation of the drawing position. [Effects of the Invention]

[0014] According to the present invention, it is possible to suppress changes in deflection voltage when switching between deflection regions, thereby improving drawing accuracy. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a drawing apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a conceptual diagram illustrating a deflection region. [Figure 3] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 4] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 5] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 6] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 7] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 8]10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 9] 9A and 9B are diagrams showing examples of pattern arrangements within the sub deflection region. [Figure 10] FIG. 10 is a diagram showing an example of division of a sub deflection region. [Figure 11] 10A and 10B are diagrams for explaining the drawing order of TFs in the sub deflection area. [Figure 12] 1A and 1B are diagrams illustrating a deflection operation sequence in a multi-beam writing apparatus. [Figure 13] FIG. 1 is a diagram illustrating the drawing order of a conventional TF. DETAILED DESCRIPTION OF THE INVENTION

[0016] In the following embodiments, 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 also be used. Furthermore, a variable-shape drawing apparatus will be described as an example of a charged particle beam apparatus.

[0017] Fig. 1 is a conceptual diagram showing the configuration of a drawing apparatus according to an embodiment. In Fig. 1, drawing apparatus 100 includes drawing unit 150 and control unit 160. Drawing unit 150 includes electron optical column 102 and drawing chamber 103. Inside electron optical column 102, an electron gun 201, an illumination lens 202, a blanking deflector (blanker) 212, a blanking aperture 214, a first shaping aperture 203, a projection lens 204, a shaping deflector 205, a second shaping aperture 206, an objective lens 207, a main deflector 208, a sub-deflector 209, and a sub-sub-deflector 216 are arranged.

[0018] An XY stage 105 that is movable in the X and Y directions is placed in the patterning chamber 103. A substrate 101 that is coated with resist and that is to be patterned is placed on the XY stage 105. The substrate 101 includes an exposure mask, a silicon wafer, etc. for manufacturing a semiconductor device.

[0019] The control unit 160 includes a control computer 110, a memory 112, a deflection control circuit 120, DAC (digital-analog converter) amplifiers 130, 132, 134, 136, and 138 (deflection amplifiers), and a storage device 140.

[0020] DAC amplifiers 130, 132, 134, 136, and 138 are connected to the deflection control circuit 120. The DAC amplifier 130 is connected to a blanking deflector 212. The DAC amplifier 132 is connected to a sub-deflector 209. The DAC amplifier 134 is connected to a main deflector 208. The DAC amplifier 136 is connected to a sub-sub-deflector 216. The DAC amplifier 138 is connected to a shaping deflector 205.

[0021] The control computer 110 includes a shot data generation unit 50 and a drawing control unit 53. The functions of the shot data generation unit 50 and the drawing control unit 53 may be configured as software or hardware.

[0022] Fig. 2 is a conceptual diagram for explaining a deflection region. In Fig. 2, the drawing region 10 on the substrate 101 is virtually divided into a plurality of stripe regions 20 in the y direction, for example, in the shape of stripes, by the deflection width of the main deflector 208. The regions obtained by dividing the stripe region 20 in the x direction by the deflection width of the main deflector 208 become the deflection regions (main deflection regions) of the main deflector 208.

[0023] This main deflection area is virtually divided into a plurality of sub deflection areas 30 (also referred to as SF30) in a mesh shape, at a deflection possible size of the sub deflector 209. Then, each SF30 is virtually divided into a plurality of sub sub deflection areas (TF40) in a mesh shape, at a deflection possible size of the sub sub deflector 216. The SF30 and TF40 are not limited to a mesh shape (rectangle), and can have any shape.

[0024] A shot figure is written at each shot position 42 of each TF 40. In this way, the electron beam 200 is deflected by three stages of deflectors, and the deflection regions are, in order from the largest to the smallest, the main deflection region, SF30, and TF40.

[0025] A digital signal for blanking control is output from the deflection control circuit 120 to the DAC amplifier 130. The DAC amplifier 130 converts the digital signal into an analog signal, amplifies it, and applies it as a deflection voltage to the blanking deflector 212. The electron beam 200 is deflected by this deflection voltage, and blanking control for each shot is performed.

[0026] A digital signal for shaping deflection is output from the deflection control circuit 120 to the DAC amplifier 138. The DAC amplifier 138 converts the digital signal into an analog signal, amplifies it, and applies it as a deflection voltage to the deflector 205. This deflection voltage deflects the electron beam 200 to a specific position on the second shaping aperture 206, forming an electron beam of desired dimensions and shape.

[0027] A digital signal for main deflection control is output from the deflection control circuit 120 to the DAC amplifier 134. The DAC amplifier 134 converts the digital signal into an analog signal, amplifies it, and applies it to the main deflector 208 as a deflection voltage. The electron beam 200 is deflected by this deflection voltage, and the beam of each shot is deflected to a reference position A (for example, the lower left corner position of the corresponding SF 30) of a predetermined SF 30 that is virtually divided into a mesh shape. Furthermore, when drawing is performed while the XY stage 105 is continuously moving, the deflection voltage also includes a deflection voltage for tracking that follows the stage movement.

[0028] A digital signal for sub-deflection control is output from the deflection control circuit 120 to the DAC amplifier 132. The DAC amplifier 132 converts the digital signal into an analog signal, amplifies it, and applies it as a deflection voltage to the sub-deflector 209. The electron beam 200 is deflected by this deflection voltage, and the beam of each shot is deflected to the reference position B of the TF 40 (for example, the lower left corner position of the corresponding TF 40) which is the minimum deflection area.

[0029] The deflection control circuit 120 outputs a digital signal for sub-deflection control to the DAC amplifier 136. The DAC amplifier 136 converts the digital signal into an analog signal, amplifies it, and applies it as a deflection voltage to the sub-deflector 216. The electron beam 200 is deflected by this deflection voltage, and the beam of each shot is deflected to each shot position 42 within the TF 40.

[0030] In the drawing apparatus 100, a multi-stage deflector is used to perform the drawing process for each stripe region 20. Here, as an example, a three-stage deflector including a main deflector 208, a sub-deflector 209, and a sub-sub-deflector 216 is used. While the XY stage 105 continuously moves, for example, in the -x direction, drawing proceeds in the x direction for the first stripe region 20. Then, after drawing of the first stripe region 20 is completed, drawing proceeds in the same way for the second stripe region 20, or in the opposite direction. Thereafter, drawing proceeds in the same way for the third and subsequent stripe regions 20.

[0031] The main deflector 208 sequentially deflects the electron beam 200 to the reference position A of the SF 30 so as to follow the movement of the XY stage 105. The sub-deflector 209 sequentially deflects the electron beam 200 from the reference position A of each SF 30 to the reference position B of the TF 40. The sub-sub-deflector 216 then deflects the electron beam 200 from the reference position B of each TF 40 to the shot position 42 of the beam to be irradiated within that TF 40.

[0032] In this way, the main deflector 208, the sub-deflector 209, and the sub-sub-deflector 216 have deflection areas of different sizes. The TF 40 is the smallest deflection area among the deflection areas of the multiple stages of deflectors.

[0033] The storage device 140 is, for example, a magnetic disk device, and stores drawing data for drawing a pattern on the substrate 101. This drawing data is design data (layout data) converted into a format for the drawing device 100, and is input to the storage device 140 from an external device and stored therein.

[0034] The shot data generation unit 50 performs multiple stages of data conversion processing on the drawing data stored in the storage device 140, divides each figure pattern to be drawn into shot figures of a size that can be irradiated in one shot, and generates shot data in a format specific to the drawing device.

[0035] The shot data includes, for example, a figure code indicating the figure type of each shot figure, figure size, shot position, and irradiation amount, which are set for each shot. The irradiation amount may be expressed as the irradiation time obtained by dividing the irradiation amount by the current density. The generated shot data is temporarily stored in memory 112. Note that the shot data generation unit 50 does not necessarily need to be provided within the control computer 110, and shot data may be generated externally and then stored in memory 112.

[0036] The writing control unit 53 transfers the shot data to the deflection control circuit 120. The deflection control circuit 120 outputs deflection data for a desired irradiation time to the DAC amplifier 130 for the blanking deflector 212.

[0037] The deflection control circuit 120 outputs deflection data to a DAC amplifier 134 for the main deflector 208 so that the beam follows the movement of the XY stage 105. The deflection control circuit 120 outputs deflection data to a DAC amplifier 132 for the sub-deflector 209, which deflects the beam to a relative position within the SF 30. The deflection control circuit 120 outputs deflection data to a DAC amplifier 136 for the sub-deflector 216, which deflects the beam to a relative position within the TF 40.

[0038] Moreover, the deflection control circuit 120 outputs deflection data to a DAC amplifier 138 for the shaping deflector 205 so that the beam has a desired shape.

[0039] An electron beam 200 emitted from an electron gun 201 (emitting portion) is deflected by the blanking deflector 212 when passing through the blanking deflector 212, for example, so that in the beam-on state the electron beam 200 passes through a blanking aperture 214, and in the beam-off state the entire beam is shielded by the blanking aperture 214. The electron beam 200 that passes through the blanking aperture 214 from the beam-off state until the beam is turned on and then turned off constitutes one electron beam shot.

[0040] The electron beam 200 of each shot, generated by passing through the blanking deflector 212 and the blanking aperture 214, is illuminated by the illumination lens 202 onto the entire first shaping aperture 203, which has a rectangular hole. Here, the electron beam 200 is first shaped into a rectangle.

[0041] The electron beam 200 of the first aperture image that has passed through the first shaping aperture 203 is projected onto the second shaping aperture 206 by the projection lens 204. The deflection of the first aperture image on the second shaping aperture 206 is controlled by the shaping deflector 205, making it possible to change the beam shape and dimensions (perform variable shaping). Such variable shaping is performed for each shot, and it is possible to form the beam into a different shape and dimensions for each shot.

[0042] The electron beam 200 of the second aperture image that has passed through the second shaping aperture 206 is focused by the objective lens 207, deflected by the main deflector 208, the sub-deflector 209, and the sub-sub-deflector 216, and irradiated onto a desired position on the substrate 101 placed on the continuously moving XY stage 105. As described above, a plurality of shots of the electron beam 200 are deflected by each deflector in turn onto the substrate 101 that will become the substrate.

[0043] In this embodiment, the drawing order of the TFs 40 in one SF 30 is reversed from the drawing order of the TFs 40 in the previous SF 30.

[0044] For example, as shown in FIG. 3, in the (N-1)th (N is an integer equal to or greater than 2) SF30_1 in the main deflection region, writing starts from the bottom left TF 40 and proceeds upward (+y direction) in order. After writing by the leftmost row of TFs 40 is completed, writing by the second row of TFs 40 from the left proceeds downward (-y direction) in order. Thereafter, writing proceeds row by row in the same manner while switching the writing direction. The top right TF 40 is the last TF 40 in the writing order. After writing by the top right TF 40 is completed, the main deflector 208 deflects the electron beam from the reference position A1 of SF30_1 to the reference position A2 of SF30_2, and the SF to be written (sub-deflection region) is switched from SF30_1 to the Nth SF30_2.

[0045] As shown in FIG. 4, in SF30_2, writing starts from the top right TF 40 and proceeds downward (-y direction) in order. After writing is completed by the TFs 40 in the rightmost row, writing is proceeded upward (+y direction) by the TFs 40 in the second row from the right. Thereafter, writing proceeds row by row in the same manner while switching the writing direction. The bottom left TF 40 is the last TF 40 in the writing order. After writing is completed by the bottom left TF 40, as shown in FIG. 5, the main deflector 208 deflects the electron beam from the reference position A2 of SF30_2 to the reference position A3 of SF30_3, and the SF to be written is switched from SF30_2 to the (N+1)th SF30_3.

[0046] In SF30_3, drawing starts from the bottom left TF40. The drawing order of TF40 in SF30_3 is the same as that of SF30_1, and is the reverse order of SF30_2.

[0047] The last TF40 in the drawing order in SF30_1 and the first TF40 in the drawing order in SF30_2 are both the upper right TF40. Therefore, when the SF to be drawn is switched from SF30_1 to SF30_2, the deflection voltage applied to the sub-deflector 209 does not change. Therefore, the output voltage of the DAC amplifier 132 connected to the sub-deflector 209 does not change.

[0048] The last TF 40 in the drawing order in SF30_2 and the first TF 40 in the drawing order in SF30_3 are both the bottom-left TF 40. Therefore, when the sub-deflection area to be drawn is switched from SF30_2 to SF30_3, the deflection voltage applied to the sub-deflector 209 does not change. Therefore, the output voltage of the DAC amplifier 132 connected to the sub-deflector 209 does not change.

[0049] As described above, in this embodiment, when switching the SF to be written, it is not necessary to take into consideration the settling time of the DAC amplifier 132, and it is possible to suppress positional errors of the TF 40 and improve writing accuracy and throughput.

[0050] Drawing order information for determining the drawing order as described above is stored in the storage device 140. The shot data generation unit 50 generates shot data in order so that the drawing order of the TF 40 corresponds to the drawing order information. The drawing control unit 53 transfers the shot data to the deflection control circuit 120 in the order in which it was generated by the shot data generation unit 50.

[0051] 3 to 5, an example was described in which SF30 is divided into 5x5 TFs 40, with the bottom left and top right TFs 40 being the first and last to be drawn, but the number of divisions of SF0 is not limited to this. Fig. 6 shows an example in which SF30 is divided into 5x4 TFs 40.

[0052] In the example shown in Figure 6, in the (N-1)th SF30_1, drawing starts from the bottom left TF40 and proceeds in order upwards. After drawing of the TF40 in the leftmost column is completed, drawing proceeds in order downwards for the TF40 in the second column from the left. Thereafter, drawing proceeds in the same manner, column by column, while switching the drawing direction. The TF40 in the bottom right is the last TF40 in the drawing order.

[0053] In the Nth SF30_2, drawing starts from the bottom right TF40 and proceeds upwards. The drawing order of the TF40s in SF30_2 is the reverse of that of SF30_1. The bottom left TF40 is the last TF40 in the drawing order. In this example, the bottom left and bottom right TF40s are first / last in the drawing order.

[0054] In the examples shown in Figures 3 to 5, the drawing order of TF40 in the Nth SF30_2 is reversed to the drawing order of TF40 in the N-1th SF30_1. However, the drawing order of TF40 is not limited as long as the last TF40 in the drawing order in SF30_1 and the first TF40 in the drawing order in SF30_2 are in the same relative position within each SF.

[0055] For example, as shown in Figure 7, in the (N-1)th SF30_1, drawing starts from the bottom left TF40 and proceeds in order upwards. After drawing of the TF40 in the leftmost column is completed, drawing proceeds in order downwards for the TF40 in the second column from the left. Thereafter, drawing proceeds in the same manner, column by column, while switching the drawing direction. The TF40 in the top right is the last TF40 in the drawing order.

[0056] In the Nth SF30_2, drawing starts from the top right TF40 and proceeds in order to the left (-x direction). After drawing of the top row of TF40s is finished, drawing proceeds in order to the right (+x direction) for the TF40s in the second row from the top. The bottom left TF40 is the last TF40 in the drawing order.

[0057] In the (N+1)th SF30_3, drawing starts from the bottom left TF40. The drawing order of TF40 in SF30_3 is the same as that of SF30_1.

[0058] The SF30 may be divided into 5x4 TF40s, and the drawing order may be as shown in Figure 8. That is, in the (N-1)th SF30_1, drawing starts from the bottom left TF40 and proceeds upwards. After drawing of the TF40s in the leftmost column is completed, drawing proceeds downwards for the TF40s in the second column from the left. Thereafter, drawing proceeds column by column in the same manner, while switching the drawing direction. The bottom right TF40 is the last TF40 in the drawing order.

[0059] In the Nth SF30_2, drawing starts from the bottom right TF40 and proceeds in order to the left. After drawing of the TF40 in the bottom row is finished, drawing proceeds in order to the right for the TF40 in the second row from the bottom. The top left TF40 is the last TF40 in the drawing order.

[0060] In the (N+1)th SF30_3, drawing starts from the top left TF40 and proceeds downwards. After drawing of the leftmost TF40 has finished, drawing proceeds upwards for the TF40 in the second row from the left. The top right TF40 is the last TF40 in the drawing order.

[0061] In the (N+2)th SF30_4, drawing starts from the top right TF40 and proceeds in order to the left. After drawing of the top row of TF40s is finished, drawing proceeds in order to the right of the TF40s in the second row from the top. The bottom left TF40 is the last TF40 in the drawing order.

[0062] The drawing order of TF40 in SF30_5, which is the (N+3)th position, is the same as that of SF30_1. In this example, four patterns of drawing order of TF40 are repeatedly used.

[0063] In the above embodiment, an example has been described in which writing patterns are arranged in all TFs 40 in an SF 30, but there may be a TF 40 in which no writing pattern is arranged. For example, as shown in Figures 9A and 9B, there may be a case in which no writing pattern is arranged in the Nth SF 30_2 at a position corresponding to the TF 40 in which writing was last performed in the (N-1)th SF 30_1.

[0064] In this case, based on the shot data, drawing should start from the position of the TF40 of the Nth SF30_2 where the pattern closest to the position corresponding to the TF40 last drawn in the N-1th SF30_1 is placed, i.e., the position where the displacement (movement distance) of the relative position in SF30 is the closest.

[0065] Alternatively, the process can be simplified as follows. For example, the (N-1)th SF30_1 is divided into several sections. For example, as shown in FIG. 10, it is divided into four sections (first to fourth quadrants). Then, it is determined in which section the TF40 that last performed drawing in SF30_1 is located.

[0066] In the Nth SF30_2, drawing starts from the TF 40 in the determined section. For example, in the example shown in Fig. 9A, the TF 40 that last performed drawing in SF30_1 is located in the first quadrant. Therefore, as shown in Fig. 11, in SF30_2, drawing starts from the TF 40 located in the first quadrant.

[0067] That is, the movement distance (displacement of relative position) or deflection voltage change does not necessarily have to be minimized, but only needs to be within a certain threshold. For example, if SF30 is divided into four sections as described above, the threshold may be set so that the movement distance is less than half the size of SF30.

[0068] The order of intermediate deflection operations other than the first and last ones is arbitrary, but it is preferable to set the order of deflection operations so that the sum of the sub-deflection movement distances is small.

[0069] In this way, the TF 40 that last performed drawing in SF30_1 and the TF 40 that first performs drawing in SF30_2 are relatively located in the same section, thereby suppressing the amount of movement of SF30 and suppressing changes in the deflection voltage applied to the sub-deflector 209. Therefore, changes in the output voltage of the DAC amplifier 132 connected to the sub-deflector 209 become smaller, and drawing accuracy can be improved.

[0070] Alternatively, the relative position may be varied in advance, and the variation (fluctuation) in the drawing position may be measured when a predetermined settling time (for example, the settling time required for the deflection distance of two TFs) is used for drawing, and the relationship between the displacement of the relative position and the drawing position variation may be determined, and a threshold may be set based on the displacement of the relative position at which the drawing position variation falls within a predetermined range (for example, within the required drawing accuracy).

[0071] Although the above embodiment has been described as an example of a lithography system using a single beam, the present invention can also be applied to a lithography system using multiple beams. However, in a multi-beam lithography system, it is preferable that the order of deflection operations within an SF is constant.

[0072] In this case, as shown in FIG. 12, the deflection operation order may be determined so that the first deflection position (#1) and the last deflection position (#25) in the SF are close to each other (adjacent to each other).

[0073] The order of deflection operations other than the first and last is arbitrary, but it is preferable to use an order of deflection operations that minimizes changes in deflection voltage. In the example shown in Fig. 12, except for #13 to #14, the deflection amount is two TFs or less in the x direction and two TFs or less in the y direction, or one TF in each of the x and y directions, thereby minimizing changes in deflection voltage.

[0074] In the above embodiment, a drawing device having three stages of deflectors, namely, a main deflector, a sub-deflector, and a sub-sub-deflector, has been described, but the present invention can also be applied to a drawing device of a two-stage deflection system in which the sub-sub-deflector is omitted. For example, the drawing order of the TFs 40 in the SF shown in Figures 3 to 11 may be replaced with the shot order in the SF.

[0075] The present invention is not limited to the above-described embodiments, and the components can be modified and embodied in practice without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining multiple components disclosed in the above-described embodiments. For example, some components may be omitted from all the components shown in the embodiments. Furthermore, components from different embodiments may be appropriately combined. [Explanation of symbols]

[0076] 50 Shot data generation unit 53 Drawing control unit 100 drawing device 110 Control computer 150 Drawing section 160 control section

Claims

1. A charged particle beam writing method for writing a pattern on a substrate by deflecting a charged particle beam with a deflector, comprising: Dividing a drawing region of the substrate into a plurality of deflection regions, and deflecting the charged particle beam sequentially to reference positions of the plurality of deflection regions; Dividing the deflection region into a plurality of small regions, and deflecting the charged particle beam from a reference position of the deflection region to reference positions of the plurality of small regions in order; deflecting the charged particle beam from a reference position of the small area to a predetermined position within the small area to write a pattern; a relative positional displacement between a subregion in which a pattern is drawn last in an (N-1)th deflection region (N is an integer of 2 or more) and a subregion in which a pattern is drawn first in an Nth deflection region is within a predetermined threshold value; A charged particle beam drawing method, wherein the predetermined threshold is set based on a relationship between a displacement of the relative position obtained in advance and fluctuation of the drawing position.

2. 2. The charged particle beam writing method according to claim 1, wherein the small area in which a pattern is drawn last in the (N-1)th deflection area (N is an integer of 2 or more) and the small area in which a pattern is drawn first in the Nth deflection area are located at the same relative positions in each deflection area.

3. 3. The charged particle beam drawing method according to claim 2, wherein the drawing order of the plurality of small regions in an Nth (N is an integer greater than or equal to 2) deflection region is the reverse order of the drawing order of the plurality of small regions in an N-1th deflection region.

4. an emission section that emits a charged particle beam; a deflector that adjusts the irradiation position of the charged particle beam with respect to a substrate placed on a stage; a control unit for controlling the deflector; Equipped with The deflector comprises: a first deflector that deflects the charged particle beam to reference positions of a plurality of deflection regions into which a drawing region of the substrate is divided, so as to follow the movement of the stage; a second deflector that deflects the charged particle beam from a reference position of each deflection region to reference positions of a plurality of small regions into which each deflection region is divided; and the control unit controls the deflector so that a displacement of a relative position between a small region in which a pattern is drawn last in an (N-1)th deflection region (N is an integer of 2 or more) and a small region in which a pattern is drawn first in an Nth deflection region is within a predetermined threshold value; The predetermined threshold value is set based on a relationship between a displacement of the relative position and a fluctuation of the writing position, which is determined in advance.

5. 5. The charged particle beam drawing apparatus according to claim 4, wherein the control unit controls the deflector so that a small area in which a pattern is drawn last in an N-1th deflection area (N is an integer of 2 or more) and a small area in which a pattern is drawn first in an Nth deflection area are relatively positioned at the same position in each deflection area.

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