Method for acquiring stage speed, method for drawing by multi-charged-particle-beam, and method for acquiring combinations of stage speed and multiplicity in drawing by multi-charged-particle-beam

Abstract

PURPOSE: To provide a device capable of acquiring drawing conditions that suppress an increase in drawing time within a range that avoids degradation or resist alteration liable to cause difficulty in correcting CD accuracy.CONSTITUTION: A method for acquiring a stage speed according to an embodiment of the present invention is a method for acquiring a stage speed for performing drawing on a substrate with a charged particle beam while moving a stage on which a substrate coated with a resist is placed. The method includes: storing, in a storage device, relation data of the relations among the stage speed of the stage, the dose amount per drawing process, and the temperature rise of the resist; reading the relationship data from the storage device by a processing circuit; using the relationship data to acquire a stage speed at which the temperature rise of the resist becomes equal to or lower than a preset allowable temperature rise and outputting the stage speed by the processing circuit.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a stage velocity acquisition method, a stage velocity acquisition device, a multi-charged particle beam writing method, a method for acquiring a combination of stage velocity and multiplicity in multi-charged particle beam writing, a multi-charged particle beam writing device, and a program (or a readable recording medium on which a program is non-temporarily recorded), and relates to, for example, a writing technique that suppresses the rise in temperature of a resist on a substrate in multi-beam writing to within an allowable temperature range. [Background technology]

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

[0003] For example, there are lithography systems that use multiple beams. Compared to lithography using a single electron beam, using multiple beams allows for the irradiation of multiple beams at once, significantly improving throughput. However, while multi-beam lithography reduces the current density compared to single-beam lithography, it has been found that significant resist heating can occur depending on the lithography conditions. This can lead to problems such as deterioration that makes it difficult to correct CD accuracy and resist deterioration. To address this issue, it is necessary to suppress the temperature rise on the substrate caused by the lithography process. On the other hand, performing lithography in a way that suppresses the temperature rise on the substrate can result in a decrease in throughput. For this reason, it is necessary to increase throughput as much as possible without causing deterioration that makes it difficult to correct CD accuracy or resist deterioration.

[0004] Here, a method has been disclosed in which the temperature distribution on a sample when writing is performed at a predetermined multiplicity is predicted, and the multiplicity is determined for each pattern based on this temperature distribution (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-030301 Summary of the Invention [Problem to be solved by the invention]

[0006] One aspect of the present invention provides an apparatus and method capable of acquiring drawing conditions that suppress an increase in drawing time within a range that does not cause deterioration of CD accuracy that is difficult to correct or resist deterioration. [Means for solving the problem]

[0007] Furthermore, a stage velocity acquisition method according to an aspect of the present invention includes: 1. A method for acquiring a stage velocity for performing drawing on a substrate coated with a resist with a charged particle beam while moving a stage on which the substrate is placed, the method comprising: storing data relating to the relationship between the stage speed, the dose per drawing process, and the temperature rise of the resist in a storage device; a processing circuit reading out the relationship data from the storage device, and using the relationship data, obtaining and outputting a stage speed at which the temperature rise of the resist is equal to or lower than a preset allowable temperature rise; It is characterized by:

[0008] A multi-charged particle beam writing method according to one aspect of the present invention includes: storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with resist, the dose per one drawing process in multiple drawing, and the temperature rise of the resist in a storage device; reading out the relational data from the storage device, and using the relational data, obtaining a combination of a stage speed capable of writing and a degree of multiplicity in multiple writing, which allows the temperature rise of the resist to fall within the allowable temperature rise range; Using the multi-charged particle beam, a pattern is drawn on a substrate placed on the stage through a drawing process according to the combination of the acquired stage speed and multiplicity. It is characterized by:

[0009] A method for acquiring a combination of stage speed and multiplicity in multi-charged particle beam writing according to one aspect of the present invention includes the steps of: storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with resist, the dose per one drawing process in multiple drawing, and the temperature rise of the resist in a storage device; reading out the relational data from the storage device, and using the relational data, obtaining a combination of a stage speed capable of writing and a multiplicity in the multiple writing, which allows the temperature rise of the resist to fall within the allowable temperature rise range, and outputting the combination; It is characterized by:

[0010] A multi-charged particle beam writing apparatus according to one aspect of the present invention comprises: a storage device that stores data relating to the relationship between the stage speed of a stage on which a substrate coated with resist is placed, the dose per one lithography process in multiple lithography, and the temperature rise of the resist; a combination acquisition circuit that reads out the relational data from the storage device and acquires a combination of a stage speed capable of writing and a multiplicity in multiple writing, which allows the temperature rise of the resist to fall within a tolerable temperature rise range, using the relational data; a drawing mechanism including a stage and an optical system that generates a multi-charged particle beam and controls the trajectory of the multi-charged particle beam, and that draws a pattern on a substrate placed on the stage by using the multi-charged particle beam through a drawing process that corresponds to a combination of the acquired stage speed and multiplicity; The present invention is characterized by the following features.

[0011] A program according to one aspect of the present invention comprises: a process of storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with a resist in multi-beam lithography, the dose per lithography process in multiple lithography, and the temperature rise of the resist in a storage device; a process of reading the relationship data from the storage device, and using the relationship data to obtain a combination of a stage speed capable of writing and a multiplicity in the multiple writing, which allows the temperature rise of the resist to fall within a tolerable temperature rise range, and outputting the combination; to be executed by the computer. [Effects of the Invention]

[0012] According to one aspect of the present invention, it is possible to acquire writing conditions that suppress an increase in writing time within a range that does not cause deterioration of CD accuracy that is difficult to correct or resist deterioration. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a conceptual diagram showing an example of the configuration of a drawing device according to the first embodiment. [Figure 2] FIG. 2 is a conceptual diagram showing an example of the configuration of a shaping aperture array substrate according to the first embodiment. [Figure 3] 2 is a cross-sectional view showing an example of the configuration of a blanking aperture array mechanism according to the first embodiment. FIG. [Figure 4] FIG. 2 is a conceptual diagram for explaining an example of a drawing area in the first embodiment. [Figure 5] FIG. 2 is a diagram showing an example of a multi-beam array according to the first embodiment. [Figure 6] FIG. 2 is a diagram for explaining an example of a multi-beam writing operation according to the first embodiment. [Figure 7] FIG. 4 is a diagram showing an example of the relationship between the temperature rise of the resist and the pattern dimension in the first embodiment. [Figure 8] FIG. 4 is a diagram showing an example of the relationship between the temperature rise of the resist and the deterioration of the resist in the first embodiment. [Figure 9] FIG. 2 is a flowchart showing an example of main steps of the writing method according to the first embodiment. [Figure 10] FIG. 3 is a diagram showing an example of a temperature rise model of a resist according to the first embodiment. [Figure 11] FIG. 3 is a diagram showing an example of relationship data according to the first embodiment. [Figure 12] 3 is a block diagram showing an example of the internal configuration of a combination acquisition unit according to the first embodiment. FIG. [Figure 13] FIG. 10 is a diagram showing an example of the relationship between the stage speed Vstage at the allowable temperature rise and the dose D per writing process in multiple writing in the first embodiment. [Figure 14] 10 is a diagram showing an example of the relationship between the stage speed Vstage at an allowable temperature rise and the dose D per writing process in multiple writing, and an example of the dose for each degree of multiplicity, according to the first embodiment. FIG. [Figure 15] FIG. 4 is a diagram showing an example of the relationship between writing time, resist sensitivity, and multiplicity in the first embodiment. [Figure 16] FIG. 10 is a diagram showing another example of the relationship between the writing time, resist sensitivity, and multiplicity in the first embodiment. [Figure 17] FIG. 11 is a block diagram showing an example of the internal configuration of a combination acquisition unit according to the second embodiment. [Figure 18] FIG. 10 is a flowchart showing an example of some of the main steps of the writing method according to the second embodiment. [Figure 19] FIG. 10 is a flowchart showing an example of the remaining main steps of the writing method according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] In the following embodiments, a configuration using an electron beam will be described as an example of a charged particle beam, but the charged particle beam is not limited to an electron beam and may be a beam using charged particles such as an ion beam.

[0015] Embodiment 1 FIG. 1 is a conceptual diagram showing an example of the 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 circuit 160. The drawing apparatus 100 is an example of a multi-charged particle beam drawing apparatus and also an example of a multi-charged particle beam exposure apparatus. The drawing mechanism 150 includes an electron lens barrel 102 (electron beam column) and a drawing chamber 103. Inside the electron lens barrel 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, a deflector 208, and a deflector 209 are arranged, constituting an optical system that generates a multi-charged particle beam and controls its trajectory.

[0016] An XY stage 105 is disposed within the patterning chamber 103. A substrate 101, which will be the patterned substrate during patterning (exposure), is disposed on the XY stage 105. A resist is applied to the substrate 101. The substrate 101 includes an exposure mask used in manufacturing a semiconductor device, or a semiconductor substrate (silicon wafer) on which a semiconductor device is manufactured. The substrate 101 also includes a mask blank on which nothing has yet been patterned. A mirror 210 for measuring the position of the XY stage 105 is also disposed on the XY stage 105.

[0017] The control system circuit 160 includes a control computer 110, a memory 112, a deflection control circuit 130, digital-to-analog conversion (DAC) amplifier units 132 and 134, a lens control circuit 136, a stage control mechanism 138, a stage position measurement device 139, and storage devices 140, 142, and 144 such as magnetic disk drives. The control computer 110, the memory 112, the deflection control circuit 130, the lens control circuit 136, the stage control mechanism 138, the stage position measurement device 139, and the storage devices 140, 142, and 144 are connected to one another via a bus (not shown). The deflection control circuit 130 is connected to the DAC amplifier units 132 and 134 and a blanking aperture array mechanism 204. The deflector 209 is composed of four or more electrodes, and each electrode is controlled by the deflection control circuit 130 via the DAC amplifier 132. The deflector 208 is composed of four or more electrodes, and each electrode is controlled by a deflection control circuit 130 via a DAC amplifier 134. The electron lens group (e.g., an electromagnetic lens group or an electrostatic lens group) such as the illumination lens 202, the reduction lens 205, and the objective lens 207 is controlled by a lens control circuit 136.

[0018] The position of the XY stage 105 is controlled by driving motors (not shown) for each axis controlled by a stage control mechanism 138. A stage position measuring device 139 receives light reflected from a mirror 210 and measures the position of the XY stage 105 based on the principle of laser interferometry.

[0019] The control computer 110 includes a pattern density (ρ) calculation unit 50, a dose (D) calculation unit 52, a temperature rise calculation unit 53, a relationship data creation unit 54, a combination acquisition unit 56, a drawing data processing unit 70, a data processing unit 71, a drawing control unit 72, and a transfer processing unit 74.

[0020] Each of the "units" such as the pattern density calculation unit 50, the dose calculation unit 52, the temperature rise calculation unit 53, the relationship data creation unit 54, the combination acquisition unit 56, the writing data processing unit 70, the data processing unit 71, the writing control unit 72, and the transfer processing unit 74 includes a processing circuit. Such a processing circuit may include, for example, an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device. Each of the "units" may use a common processing circuit (the same processing circuit) or different processing circuits (separate processing circuits). Information input to and output from the pattern density calculation unit 50, the dose calculation unit 52, the temperature rise calculation unit 53, the relationship data creation unit 54, the combination acquisition unit 56, the writing data processing unit 70, the data processing unit 71, the writing control unit 72, and the transfer processing unit 74, as well as information being calculated, is stored in the memory 112 each time.

[0021] The drawing operation of the drawing apparatus 100 is controlled by a drawing control unit 72. Furthermore, the transfer process of the irradiation time data for each shot to the deflection control circuit 130 is controlled by a transfer processing unit 74.

[0022] Furthermore, drawing data (chip data) is input from outside the drawing device 100 and stored in the storage device 140. The chip data defines information on a plurality of figure patterns that constitute the chip pattern. Specifically, for each figure pattern, for example, the coordinates of each vertex are defined in the order in which the figure is formed. Alternatively, for each figure pattern, for example, a figure code, coordinates, size, etc. are defined.

[0023] 1 shows the configuration necessary for explaining the first embodiment. The drawing device 100 may also include other configurations that are normally required.

[0024] FIG. 2 is a conceptual diagram showing an example of the configuration of a shaping aperture array substrate in the first embodiment. In FIG. 2, holes (openings) 22 are formed in a matrix of p columns (y direction) by q columns (x direction) (p, q≧2) at a predetermined arrangement pitch in shaping aperture array substrate 203. The example in FIG. 2 shows, for example, a case where 512×512 columns of holes 22 are formed in the vertical and horizontal directions (x, y directions). The number of holes 22 is not limited to this. For example, 32×32 columns of holes 22 may be formed. Each hole 22 is formed as a rectangle of the same size and shape. Alternatively, each hole 22 may be a circle of the same diameter. A portion of electron beam 200 passes through each of these multiple holes 22, thereby forming multiple beams 20. In other words, shaping aperture array substrate 203 forms multiple beams 20.

[0025] FIG. 3 is a cross-sectional view showing an example of the configuration of the blanking aperture array mechanism according to the first embodiment. As shown in FIG. 3, the blanking aperture array mechanism 204 includes a blanking aperture array substrate 31, which is made of a semiconductor substrate such as silicon, and is disposed on a support base 33. In a membrane region 330 at the center of the blanking aperture array substrate 31, passage holes 25 (openings) for passing each beam of the multi-beams 20 are formed at positions corresponding to the holes 22 of the shaping aperture array substrate 203 shown in FIG. 2. Pairs of control electrodes 24 and counter electrodes 26 (blankers: blanking deflectors) are disposed at positions facing each other across the corresponding passage holes 25 among the plurality of passage holes 25. A control circuit 41 (logic circuit) is disposed on the outer periphery of the blanking aperture array substrate 31, which applies a deflection voltage to the control electrodes 24 for each passage hole 25. The counter electrodes 26 for each beam are connected to ground.

[0026] When there is no potential difference between the potential of the control electrode 24 and the ground potential of the opposing electrode 26, the corresponding beam is not deflected and is irradiated, and when a potential difference is generated, the corresponding beam is deflected by the electric field and is shielded by the limiting aperture substrate 206, thereby performing blanking control so that the beam is turned off.

[0027] The multi-beams 20 that have passed through the limiting aperture substrate 206 are focused by the objective lens 207 to form a pattern image with the desired reduction ratio, and the entire multi-beams 20 that have passed through the limiting aperture substrate 206 are deflected in the same direction by the deflectors 208 and 209, and each beam is irradiated onto its respective irradiation position on the substrate 101. Furthermore, for example, when the XY stage 105 is moving continuously, the deflector 208 performs tracking control so that the beam irradiation position follows the movement of the XY stage 105.

[0028] FIG. 4 is a conceptual diagram illustrating an example of a writing region in the first embodiment. As shown in FIG. 4, the writing region 30 (thick line) (chip region) of the substrate 101 is virtually divided, for example, in the y direction into a plurality of rectangular stripe regions 32 with a predetermined width. The example of FIG. 4 shows a case in which the writing region 30 of the substrate 101 is divided, for example, in the y direction into a plurality of stripe regions 32 with a width substantially equal to the size of a designed irradiation region 34 (writing field) that can be irradiated with a single irradiation of the multibeams 20. The size in the x direction of the designed irradiation region 34 of the multibeams 20 can be defined by the number of beams in the x direction × the beam pitch in the x direction. The size in the y direction of the rectangular irradiation region 34 can be defined by the number of beams in the y direction × the beam pitch in the y direction.

[0029] In the example of FIG. 4, a stripe layer is set, which is made up of a plurality of stripe regions 32 obtained by dividing the drawing region 30.

[0030] Next, an example of the drawing operation will be described. When the multiplicity is 1 (when multiple drawing is not performed), one stripe layer is created. First, the XY stage 105 is moved and adjusted so that the irradiation area 34 of the multibeam 20 is positioned at the left end of the first stripe region 32 or further to the left. Then, drawing of the first stripe region 32 is performed. When drawing the first stripe region 32, the XY stage 105 is moved, for example, in the -x direction, so that drawing proceeds relatively in the x direction. The XY stage 105 is moved continuously, for example, at a constant speed. After drawing of the first stripe region 32 is completed, the stage position is moved in the -y direction by an amount equivalent to the width of the stripe region 32. As a result, the drawn stripe region 32 is shifted in the y direction by an amount equivalent to the width of the stripe region 32.

[0031] Next, the irradiation area 34 of the multi-beam 20 is adjusted to be located at the left end of the second stripe area 32, or at a position further to the left. Then, by moving the XY stage 105, for example, in the -x direction, drawing proceeds relatively in the x direction. In this way, drawing of the second stripe area 32 is performed. Thereafter, drawing proceeds in the same manner. In this way, the k-th stripe area 32 is drawn during one movement of the XY stage 105 in the -x direction.

[0032] In the case of multiplicity 2 (when two multiple drawing operations are performed), a first stripe layer is created for the first drawing operation and a second stripe layer is created for the second drawing operation. The first stripe layer and the second stripe layer are created with their positions shifted in the y direction by half the width of the stripe region 32. The drawing operation for the first stripe region 32 of the first stripe layer is the same as that described above. After the drawing operation for the first stripe region 32 of the first stripe layer is completed, the stage position is moved in the -y direction by an amount shifted by half the width of the stripe region 32. As a result, the stripe region 32 to be drawn moves from the first stripe region 32 of the first stripe layer to the first stripe region 32 of the second stripe layer.

[0033] Next, the irradiation area 34 of the multibeam 20 is adjusted to be located at the left end of the first stripe region 32 of the second stripe layer, or at a position further to the left. Then, by moving the XY stage 105, for example, in the -x direction, writing proceeds relatively in the x direction. In this way, writing is performed on the first stripe region 32 of the second stripe layer. As a result, multiple writing with a multiplicity of 2 has been performed on the upper half of the first stripe region 32 of the first stripe layer (the lower half of the first stripe region 32 of the second stripe layer).

[0034] After the writing process for the first stripe region 32 on the second stripe layer is completed, the stage position is moved in the -y direction by an amount equal to half the width of the stripe region 32. As a result, the stripe region 32 to be written moves from the first stripe region 32 on the second stripe layer to the second stripe region 32 on the first stripe layer. Thereafter, writing continues in the same manner.

[0035] For example, in the case of a multiplicity of 4 (when multiple drawing is performed four times), a first stripe layer is created for the first drawing process, a second stripe layer for the second drawing process, a third stripe layer for the third drawing process, and a fourth stripe layer for the fourth drawing process. The first stripe layer, second stripe layer, third stripe layer, and fourth stripe layer are created with their positions shifted from each other in the y direction by 1 / 4 of the width of the stripe region 32. Then, multiple drawing is performed four times by proceeding with drawing while shifting the stripe region of each stripe layer in the y direction by 1 / 4 of the width of the stripe region 32.

[0036] As described above, it is also preferable to perform multiple drawing by moving the stage multiple times over the same position. In this case, as described above, it is preferable to perform multiple drawing while shifting the position of the stripe region in the y direction by an amount of shift that is 1 / n of the width of the stripe region. It is also possible to perform multiple drawing by overlapping the positions of the stripe regions without shifting them.

[0037] In the above example, a case has been described in which each position within a stripe region of one stripe layer is written once during one stage movement (one pass) in the -x direction, but the method of multiple writing is not limited to this. Each position within the stripe region may be written multiple times during one pass operation. For example, the first writing may be performed with the right half of the beam group in the x direction of the multi-beam 20, and the second writing may be performed at the same position with the left half of the beam group. For ease of understanding, the following description will be given of a case in which each position within the stripe region is written once per pass.

[0038] 4 shows the case where the writing of each stripe region 32 proceeds in the same direction, but this is not limiting. For example, the next stripe region 32 to be written after the stripe region 32 written in the x direction may be written in the -x direction by moving the XY stage 105 in the x direction, for example. By writing while alternating directions in this way, the writing time can be shortened.

[0039] FIG. 5 is a diagram showing an example of a multibeam array according to the first embodiment. The example of FIG. 5 shows, for example, an 8×8 multibeam array 20. The beam array size L in the x direction is defined by the inter-beam pitch in the x direction multiplied by the number of beams in the x direction. The beam array size L in the y direction is defined by the inter-beam pitch in the y direction multiplied by the number of beams in the y direction. The area surrounded by the beam array size L in the x direction × the beam array size L in the y direction is the multibeam irradiation area 34. In the example of FIG. 5, the inter-beam pitch is, for example, a distance of 4 pixels 36. Therefore, the sub-irradiation area 29 of each beam 28 constituting the multibeam 20 is the area surrounded by the inter-beam pitch in the x direction and the inter-beam pitch in the y direction. In the example of FIG. 5, the sub-irradiation area 29 is composed of 4×4 pixels.

[0040] Fig. 6 is a diagram for explaining an example of a multi-beam writing operation in the first embodiment. The example of Fig. 6 shows a case where writing is performed with four different beams in each sub-irradiation area 29, which includes one beam irradiation position of each of the multi-beams 20 and is surrounded by the beam pitch. The example of Fig. 6 also shows a writing operation in which the XY stage 105 moves continuously at a speed corresponding to a distance of 8 beam pitches while writing 1 / 4 of the area in each sub-irradiation area 29 (one corresponding to the number of beams used for irradiation). The example of Fig. 6 shows a case where each sub-irradiation area 29 is composed of, for example, 4 x 4 pixels.

[0041] In the drawing operation shown in the example of FIG. 6 , for example, while the XY stage 105 moves a distance of eight beam pitches in the x direction, the deflector 209 sequentially shifts the irradiation position (pixel 36) while firing four shots of the multibeam 20 in a shot cycle to draw (expose) four different pixels 36 in the same sub-irradiation area 29. While drawing (exposing) these four pixels 36, the deflector 208 deflects the entire multibeam 20 collectively so that the relative position of the irradiation area 34 with respect to the substrate 101 does not shift due to the movement of the XY stage 105, thereby causing the irradiation area 34 to follow the movement of the XY stage 105. In other words, tracking control is performed. When one tracking cycle is completed, tracking is reset and the system returns to the previous tracking start position. Since the drawing of the first pixel row from the right in each sub-irradiation area 29 has been completed, after a tracking reset, in the next tracking cycle, the deflector 209 first deflects the beam to align (shift) the drawing position so that the beam draws an undrawn pixel row, for example, the second pixel row from the right, in each sub-irradiation area 29. By repeating this operation during drawing of the stripe area 32, the positions of the irradiation areas 34 (34a to 34o) of the multi-beam 20 are sequentially moved, and drawing is performed, as shown in the lower diagram of FIG.

[0042] After the tracking is reset, during the next tracking control, four pixels in the same sub-irradiation area are written with different beams, each eight beams apart in the x direction. Thus, four tracking controls complete single writing for all pixels in each sub-irradiation area using four different beams. Therefore, if the sub-irradiation area 29 is composed of, for example, 4 × 4 pixels, and four shots are performed during one tracking control that moves eight beam pitches, the substrate 101 is written with 32 (= 4 × 8) beams arranged in the x direction in each row in the y direction. If the sub-irradiation area 29 is composed of, for example, 16 × 16 pixels, and eight shots are performed during one tracking control that moves 16 beam pitches, the substrate 101 is written with 512 (= 32 × 16) beams arranged in the x direction in each row in the y direction. Multiple writing is performed by repeatedly writing the same stripe area 32 by moving the XY stage 105 multiple times using the multiple beams required for single writing, as described above.

[0043] Note that multiple drawing may be performed in one pass in a drawing operation in which the sub-irradiation area 29 is composed of, for example, 4x4 pixels and four shots are taken during one tracking control of a movement of eight beam pitches. For example, if the multi-beam 20 is composed of, for example, 64 beams in the x direction, such drawing operation enables multiple drawing with a multiplicity of 2 in one pass. The multiplicity can be further increased by arranging more beams in the x direction.

[0044] As described above, problems may occur, such as deterioration of the dimensional (CD) accuracy of the pattern to be written, which makes it difficult to correct, or deterioration of the resist, due to a rise in temperature of the resist applied to the substrate 101. To address these problems, it is necessary to suppress the rise in temperature of the substrate due to the writing process.

[0045] FIG. 7 is a diagram showing an example of the relationship between the resist temperature rise and the pattern dimension in the first embodiment. In FIG. 7, the vertical axis represents the pattern dimension (CD), and the horizontal axis represents the simulated temperature rise ΔT. In the example of FIG. 7, it can be seen that the pattern dimension (CD) increases as the resist temperature rises. Furthermore, when the resist temperature rise ΔT (relative temperature) from room temperature (e.g., 20° C.) is in the range of 100 K or less, the temperature rise and CD can be approximated as changing linearly (linearly proportional). Therefore, if the resist temperature rise is within this range, CD correction is possible during writing. Therefore, to ensure acceptable dimensional accuracy of the written pattern, it is necessary to keep the resist temperature rise ΔT (relative temperature) below 100 K, which is the temperature rise that allows correction.

[0046] 8 is a diagram showing an example of the relationship between the temperature rise of the resist and the deterioration of the resist in the first embodiment. As shown in Fig. 8, when the temperature rise ΔT (relative temperature) of the resist from room temperature (e.g., 20°C) reaches 400K, the resist melts. Therefore, in order to prevent the resist from melting, it is necessary to keep the temperature rise ΔT (relative temperature) of the resist below 400K (e.g., 300K).

[0047] The temperature of the resist can be considered to be substantially the same as the temperature of the substrate 101.

[0048] On the other hand, in order to suppress the temperature rise of the resist (temperature rise of the substrate 101), it is effective to reduce the dose per writing process of multiple writing, increase the degree of multiplicity, and / or slow down the stage speed. However, if these are done excessively, the writing time will increase more than necessary, causing problems such as unnecessarily degraded throughput. Therefore, in the first embodiment, the degree of multiplicity and the stage speed are determined so as to shorten the writing time as much as possible without causing deterioration of CD accuracy that is difficult to correct and / or resist deterioration. This will be explained in detail below.

[0049] Fig. 9 is a flowchart showing an example of main steps of the writing method according to the embodiment 1. In Fig. 9, the writing method according to the embodiment 1 carries out a series of steps including a pattern density calculation step (S102), a dose calculation step (S104), a temperature rise calculation step (S106), a relationship data creation step (S108), a combination acquisition step (S110), a shot data generation step (S130), a data processing step (S132), and a writing step (S140). The combination acquisition process (S110) includes, as its internal processes, a reference stage velocity calculation process (S112), a combination calculation process (S120), a drawing time calculation process (S122), a selection process (S124), a comparison process (S126), and a combination determination process (S128).

[0050] In the pattern density calculation step (S102), the pattern density calculation unit 50 reads out the drawing data from the storage device 140 and calculates, for each pixel 36, the pattern density ρ (area density) within the pixel 36. This process is executed for each stripe region 32, for example.

[0051] In the dose calculation step (S104), the dose calculation unit 52 first virtually divides the writing region (here, for example, the stripe region 32) into a plurality of proximity mesh regions (mesh regions for calculating proximity effect correction) in a mesh shape with a predetermined size. The size of the proximity mesh region is preferably set to about 1 / 10 of the range of influence of the proximity effect, for example, about 1 μm. The dose calculation unit 52 reads out the writing data from the storage device 140, and calculates, for each proximity mesh region, a pattern area density ρ″ of the pattern to be arranged in the proximity mesh region.

[0052] Next, the dose calculation unit 52 calculates a proximity effect correction irradiation coefficient Dp(x) (corrected irradiation dose) for correcting the proximity effect for each proximity mesh region. The unknown proximity effect correction irradiation coefficient Dp(x) can be defined by a threshold model for proximity effect correction similar to the conventional method, using the backscattering coefficient η, the irradiation dose threshold Dth of the threshold model, the pattern area density ρ", and the distribution function g(x).

[0053] Next, the dose calculation unit 52 calculates the dose D (incident irradiation dose) for irradiating each pixel 36. The dose D may be calculated, for example, as a value obtained by multiplying the reference irradiation dose Dbase by the proximity effect correction irradiation coefficient Dp and the pattern density ρ′. The reference irradiation dose Dbase can be defined, for example, as Dth / (1 / 2+η). Then, a dose map is created by mapping the dose D for each pixel.

[0054] In the temperature rise calculation step (S106), the temperature rise calculation unit 53 calculates the maximum temperature rise ΔTmax of the resist by using the total dose D0 of the irradiation area 34 of the multibeam 20 and the stage speed Vstage while making them variable.

[0055] For example, the temperature rise of the resist is calculated for each of the multiple mesh areas into which the drawing area irradiated by the multi-beam 20 is divided, based on a representative value of the dose of the beam irradiating the mesh area, the speed of the stage, and the size of the irradiation area of ​​the multi-beam 20 in the drawing progression direction.

[0056] 10 is a diagram showing an example of a temperature rise model of a resist according to the first embodiment. In the temperature rise model shown in the example of FIG. 10, it is assumed that when x=0, y=0, t=0, a solid pattern is irradiated in an irradiation area 34 of the multi-beam 20 having a size of L×L with an electron beam of acceleration voltage v, a total dose D0, and a stage speed Vstage. The maximum temperature rise ΔTmax in this case is defined as the sum of the temperature heat transfer due to the irradiation energy up to the nth tracking cycle prior to the position of x=0, y=0. By setting n to infinity ∞, the maximum temperature rise ΔTmax in this case can be defined by equation (1-1) in FIG. Equation (1-1) can be solved under the initial condition that beam irradiation uniformly heats a volume equal to the mesh size on the substrate surface multiplied by Rg, where Rg represents the range of a 50 kV electron beam within quartz. The term for each n can be solved using the general heat diffusion equation, equation (1-3) in Figure 10. Here, λ represents the thermal diffusivity of the material through which the temperature is diffusing. ndx indicates the position in the x direction of the irradiation area 34 of the multi-beam 20 n tracking cycles ago as viewed from the position of x=0. Furthermore, the function σ in equation (1-1) can be defined by equation (1-2) in Fig. 10. The total dose D0 of the irradiation area 34 of the multi-beam 20 and the stage speed Vstage are varied, and the maximum temperature rise ΔTmax for each combination of the total dose D0 and the stage speed Vstage is calculated.

[0057] In the relational data creation step (S108), the relational data creation unit 54 uses the calculated maximum resist temperature rise ΔTmax to create relational data regarding the stage speed Vstage of the stage on which the resist-coated substrate is placed, the dose D per writing process in multiple writing, and the resist temperature rise ΔT. The calculated maximum resist temperature rise ΔTmax is used as the resist temperature rise ΔT.

[0058] FIG. 11 is a diagram showing an example of relationship data in the first embodiment. In FIG. 11, the vertical axis represents the stage speed, and the horizontal axis represents the dose D per writing process in multiple writing. A relationship graph is then shown for each maximum resist temperature rise ΔTmax. The example in FIG. 11 shows the relationship between the stage speed Vstage and the dose D per writing process in multiple writing for each of the maximum resist temperature rise ΔTmax of 100 K, 200 K, and 300 K.

[0059] The created relational data is stored in the storage device 144. In the above example, the case where the relational data is created within the drawing device 100 is described, but the present invention is not limited to this. The relational data may be created offline, then input to the drawing device 100, and stored in the storage device 144.

[0060] In the combination acquisition step (S110), the combination acquisition unit 56 reads out relational data from, for example, the storage device 144, and uses the relational data to acquire a combination of the stage speed Vstage at which the resist temperature rise falls within the allowable temperature rise range and the multiplicity N in multiple writing. Specifically, the operation is as follows.

[0061] Fig. 12 is a block diagram showing an example of the internal configuration of the combination acquisition unit according to embodiment 1. In Fig. 12, combination acquisition unit 56 includes reference stage speed calculation unit 57, combination calculation unit 58, writing time calculation unit 60, selection unit 61, comparison unit 62, and combination determination unit 63. Therefore, each of the "~ units" such as the pattern density calculation unit 50, the dose calculation unit 52, the temperature rise calculation unit 53, the relationship data creation unit 54, the combination acquisition unit 56 (the reference stage speed calculation unit 57, the combination calculation unit 58, the writing time calculation unit 60, the selection unit 61, the comparison unit 62, and the combination determination unit 63), the writing data processing unit 70, the data processing unit 71, the writing control unit 72, and the transfer processing unit 74 has a processing circuit. Such a processing circuit includes, for example, an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device. Each of the "~ units" may use a common processing circuit (the same processing circuit) or different processing circuits (separate processing circuits). Information input and output to and from the pattern density calculation unit 50, dose calculation unit 52, temperature rise calculation unit 53, relationship data creation unit 54, combination acquisition unit 56 (reference stage speed calculation unit 57, combination calculation unit 58, drawing time calculation unit 60, selection unit 61, comparison unit 62, and combination determination unit 63), drawing data processing unit 70, data processing unit 71, drawing control unit 72, and transfer processing unit 74, as well as information being calculated, are stored in memory 112 each time.

[0062] In the reference stage velocity calculation step (S112), the reference stage velocity calculation unit 57 calculates a reference stage velocity V0 at which drawing is possible. The maximum stage velocity within the range at which drawing processing is possible is calculated as the reference stage velocity V0. Therefore, even if drawing processing is performed at a velocity exceeding the reference stage velocity V0, the drawing processing cannot keep up, resulting in an error. The reference stage velocity calculation unit 57 identifies the maximum dose for each chip region to be written from the created dose map. The irradiation time for the maximum dose (maximum irradiation time) is calculated by dividing the maximum dose by the current density. The shot cycle is calculated by adding the settling time to the maximum irradiation time. The tracking cycle is calculated by multiplying the shot cycle by the number of shots k during one tracking control. Therefore, for example, if the writing sequence has a multiplicity of N (N is a natural number) and performs k consecutive shots on each sub-irradiation region 29 while moving m beam pitches, the reference stage velocity calculation unit 57 calculates the reference stage velocity V0 by dividing the distance of m beam pitches by {(maximum irradiation time / N+settling time)×k}. For example, if the writing sequence is at a multiplicity of 2 (N is a natural number) and four shots are continuously taken on each sub-irradiation region 29 while moving by eight beam pitches, the reference stage velocity calculation unit 57 calculates the reference stage velocity V0 by dividing the distance of eight beam pitches by {(maximum irradiation time / 2+settling time)×4}. Here, for example, the multiplicity N is made variable and the reference stage velocity V0 at each multiplicity is calculated. The calculated data of the reference stage velocity V0 at each multiplicity is stored in the storage device 144.

[0063] (Case 1) In Case 1, a case will be described in which the multiplicity N is set in advance among the combinations of the stage speed Vstage and the multiplicity N. In Case 1, the allowable temperature rise, the resist sensitivity, and the multiplicity (here, for example, the number of passes) are input as parameters. The combination acquisition unit 56 uses the relationship data to acquire the maximum stage speed Vstage at which writing can be performed within the allowable temperature rise, according to the preset multiplicity N and the exposure sensitivity of the resist. Specific explanations will be given below.

[0064] 13 is a diagram showing an example of the relationship between the stage speed Vstage at the allowable temperature rise and the dose D per writing process in multiple writing in embodiment 1. In Fig. 13, the vertical axis represents the stage speed Vstage, and the horizontal axis represents the dose D per writing process. Here, to avoid deterioration of the resist, a temperature rise below the melting temperature of the resist (for example, 300K) is used as the allowable temperature rise. Alternatively, to avoid deterioration of the CD accuracy that is difficult to correct, a temperature rise at which the dimensional accuracy of the drawn pattern is allowable (for example, 100K) is used as the allowable temperature rise. In the example of FIG. 13, 300K is used as the allowable temperature rise. Also, in the example of FIG. 13, a case where the multiplicity N=2 is set in advance is described. Also, when the resist sensitivity is, for example, 100 μC / cm 2 The case where

[0065] In this case, first, the combination acquisition unit 56 refers to the relationship data shown in FIG. 11 and extracts a graph in which the maximum temperature rise is 300K. In the combination calculation step (S112), the combination calculation unit 58 uses the relationship data to calculate the maximum stage speed Vstage that falls within the allowable temperature rise range, according to the preset multiplicity N and the exposure sensitivity of the resist. In the example of Fig. 13, since N = 2, the dose per drawing process is 50 μC / cm, which is half the resist sensitivity. 2 Therefore, the combination calculation unit 58 refers to the relational data and determines that the dose per writing process is 50 μC / cm 2 In this case, the corresponding stage speed Vstage is calculated to be, for example, 120 mm / sec.

[0066] In Case 1, the multiplicity is preset and the drawing time is not compared depending on the multiplicity, so the drawing time calculation step (S122) and the selection step (S124) are omitted.

[0067] In the comparison step (S126), the comparison unit 62 compares the calculated stage velocity Vstage with a reference stage velocity V0 at a preset multiplicity.

[0068] In the combination determination step (S128), if the calculated stage velocity Vstage is equal to or less than the reference stage velocity V0 for the preset multiplicity as a result of the comparison, the combination determination unit 63 determines the combination to be used as the drawing condition to be the combination of the preset multiplicity and the calculated stage velocity Vstage.If the calculated stage velocity Vstage is faster than the reference stage velocity V0 for the preset multiplicity, the combination to be used as the drawing condition is determined to be the combination of the preset multiplicity and the reference stage velocity V0.This is because with a stage velocity faster than the reference stage velocity V0, the drawing process cannot keep up and drawing is not possible.

[0069] As a result, it is possible to obtain a combination of the maximum stage speed Vstage capable of writing and the degree of multiplicity N in multiple writing, which allows the resist temperature rise to fall within the allowable temperature rise range.

[0070] (Case 2) Case 2 describes a case where one combination is obtained from multiple combinations of the stage speed Vstage and the multiplicity N. The allowable temperature rise, the resist sensitivity, the maximum stage speed that can be mechanically output by the drawing apparatus 100, and the minimum stage speed are input as parameters. The combination acquisition unit 56 uses the relationship data to acquire a combination of the stage speed Vstage and the multiplicity that allows writing within the allowable temperature rise and provides the shortest writing time, according to the multiplicity N and the exposure sensitivity of the resist. This will be explained in detail below.

[0071] 14 is a diagram showing an example of the relationship between the stage speed Vstage at the allowable temperature rise and the dose D per writing process in multiple writing, and an example of the dose for each degree of multiplicity, in accordance with the first embodiment. In FIG. 14, the vertical axis represents the stage speed Vstage, and the horizontal axis represents the dose per writing process. In Case 2, the allowable temperature rise is set to 300 K, as in Case 1. In the example of FIG. 14, the resist sensitivity is set to, for example, 100 μC / cm 2 The case where

[0072] In this case, first, the combination acquisition unit 56 refers to the relationship data shown in FIG. 11 and extracts a graph in which the maximum temperature rise is 300K.

[0073] In the combination calculation step (S120), the combination calculation unit 58 uses the relationship data to calculate a plurality of combinations of the stage speed Vstage and the multiplicity N according to the exposure sensitivity of the resist. The example in FIG. 14 shows the cases of multiplicity N=1 (1 pass) and multiplicity N=2 (2 passes). In the example in FIG. 14, for example, when N=1, the dose per writing process is 100 μC / cm, which is the resist sensitivity. 2 Therefore, the combination calculation unit 58 refers to the relational data and determines that the dose per writing process is 100 μC / cm 2 In this case, the stage speed Vstage is calculated to be, for example, 50 mm / sec. In addition, when N=2, the dose per drawing process is 50 μC / cm, which is half the resist sensitivity. 2 Therefore, the combination calculation unit 58 refers to the relational data and determines that the dose per writing process is 50 μC / cm 2 In this case, the stage speed Vstage is calculated to be, for example, 120 mm / sec. In addition, when N=4, the dose per drawing process is 25 μC / cm, which is 1 / 4 of the resist sensitivity. 2 Therefore, the combination calculation unit 58 refers to the relational data and determines that the dose per writing process is 25 μC / cm 2 In this case, the stage speed Vstage is calculated to be, for example, 250 mm / sec. If the maximum stage speed that can be mechanically output by the drawing apparatus 100 is, for example, 200 mm / sec, the case of multiplicity 4 is excluded. If the minimum stage speed that can be mechanically output by the drawing apparatus 100 is, for example, 20 mm / sec, the cases of multiplicity 1 and 2 are maintained as they are because they are within the range that can be output.

[0074] Furthermore, it is preferable that the combination calculation unit 58 varies the resist sensitivity and calculates a plurality of combinations of the stage speed Vstage and the multiplicity N for each resist sensitivity.

[0075] In the writing time calculation step (S122), the writing time calculation unit 60 calculates the writing time required for writing under the writing conditions of each of the acquired combinations. For example, the writing time calculation unit 60 calculates the writing time by multiplying the time T required for the XY stage 105 to travel the length of the stripe region 32 at the stage speed of each combination plus the time required for the stage to move to the next stripe region by the number of stripe regions per chip region and the degree of multiplicity.

[0076] FIG. 15 is a diagram showing an example of the relationship between writing time, resist sensitivity, and multiplicity in the first embodiment. In FIG. 15, the vertical axis represents writing time, and the horizontal axis represents resist sensitivity. The example in FIG. 15 shows writing with multiplicity 1 (1 pass), writing with multiplicity 2 (2 passes), writing with multiplicity 3 (3 passes), and writing with multiplicity 4 (4 passes). As shown in FIG. 15, depending on the resist sensitivity, the writing time may be shorter when writing with multiplicity 2 (2 passes), writing with multiplicity 3 (3 passes), or writing with multiplicity 4 (4 passes) than when writing with multiplicity 1 (1 pass). Similarly, depending on the resist sensitivity, the writing time may be shorter when writing with multiplicity 3 (3 passes) or writing with multiplicity 4 (4 passes) than when writing with multiplicity 2 (2 passes). Similarly, depending on the resist sensitivity, the writing time may be shorter when writing with multiplicity 4 (4 passes) than when writing with multiplicity 3 (3 passes).

[0077] 16 is a diagram showing another example of the relationship between the writing time, resist sensitivity, and multiplicity in the first embodiment. The example in FIG. 16 shows the multiplicity at which the writing time is shortest depending on the resist sensitivity. In the example in FIG. 16, for example, when the resist sensitivity is 0 to 110 μC / cm 2In this range, it can be seen that the writing time is shortest when writing with a multiplicity of 1 (1 pass). For example, when the resist sensitivity is 110 to 170 μC / cm 2 In this range, it can be seen that the writing time is shortest when writing with a multiplicity of 2 (2 passes). For example, when the resist sensitivity is 170 to 225 μC / cm 2 In this range, it can be seen that the writing time is shortest when writing with a multiplicity of 3 (3 passes). For example, when the resist sensitivity is 225 μC / cm 2 It can be seen that in the range above , the drawing time is shortest when drawing with a multiplicity of 4 (4 passes).

[0078] In the selection step (S124), the selection unit 61 inputs the sensitivity of the resist applied to the target substrate 101 from among the calculated combinations, and selects from the combinations a combination of multiplicity N and stage speed V that shortens the writing time for that resist sensitivity. In the example of FIG. 14, for example, 2 16, the writing time is shorter when the multiplicity is 1 (pass 1). Therefore, the selection unit 61 selects the combination of the multiplicity 1 (pass 1) and a stage speed of 120 mm / sec.

[0079] In the comparison step (S126), the comparison unit 62 compares the selected stage velocity Vstage with the reference stage velocity V0 at the selected multiplicity.

[0080] In the combination determination step (S128), if the calculated stage velocity Vstage is equal to or less than the reference stage velocity V0 for the selected multiplicity as a result of the comparison, the combination determination unit 63 determines the combination to be used as the drawing condition to be the combination of the selected multiplicity and stage velocity Vstage.If the selected stage velocity Vstage is faster than the reference stage velocity V0, the combination to be used as the drawing condition is determined to be the combination of the selected multiplicity and the reference stage velocity V0.This is because with a stage velocity faster than the reference stage velocity V0, the drawing process cannot keep up and drawing is not possible.

[0081] As a result, it is possible to obtain a combination of the maximum stage speed Vstage capable of writing and the degree of multiplicity N in multiple writing, which allows the resist temperature rise to fall within the allowable temperature rise range.

[0082] In the shot data generation step (S130), the writing data processing unit 70 uses the dose map to calculate the irradiation time for each pixel 36. The irradiation time for each pixel 36 can be calculated by dividing the dose (incident irradiation amount) D of the pixel by the current density J.

[0083] In the data processing step (S132), the data processing unit 71 rearranges the obtained irradiation time data for each pixel 36 in shot order and stores the data in the storage device 142. The transfer processing unit 74 transfers the irradiation time data to the deflection control circuit 130 in shot order.

[0084] In the drawing process (S140), under the control of the drawing control unit 76, the drawing mechanism 150 uses the multi-beam 20 to draw a pattern on the substrate 101 placed on the XY stage 105 in a drawing process that corresponds to the combination of the acquired stage speed Vstage and multiplicity N.

[0085] As described above, according to the first embodiment, it is possible to acquire writing conditions that suppress an increase in writing time without causing deterioration of CD accuracy that is difficult to correct or resist deterioration. Furthermore, it is possible to easily determine the multiplicity and stage speed that can suppress an increase in writing time within the writing apparatus 100.

[0086] Embodiment 2 In the second embodiment, a configuration will be described in which the above-mentioned cases 1 and 2 are combined and no rendering can be selected. The configuration of the rendering device in the second embodiment is the same as that in Fig. 1. Points that are not particularly explained below are the same as those in the first embodiment.

[0087] Fig. 17 is a block diagram showing an example of the internal configuration of a combination acquisition unit in embodiment 2. Fig. 17 is the same as Fig. 12 except that combination acquisition unit 56 further includes a stage velocity calculation unit 64, a comparison unit 66, a user information acquisition unit 67, a determination unit 68, and a determination unit 69. Combination acquisition unit 56 (or control computer 110) and storage device 144 are an example of a stage velocity acquisition device. Therefore, each of the "~" units, such as the pattern density calculation unit 50, the dose calculation unit 52, the temperature rise calculation unit 53, the relationship data creation unit 54, the combination acquisition unit 56 (the reference stage speed calculation unit 57, the combination calculation unit 58, the writing time calculation unit 60, the selection unit 61, the comparison unit 62, the combination determination unit 63, the stage speed calculation unit 64, the comparison unit 66, the user information acquisition unit 67, the determination unit 68, and the determination unit 69), the writing data processing unit 70, the data processing unit 71, the writing control unit 72, and the transfer processing unit 74, has a processing circuit. Such a processing circuit includes, for example, an electric circuit, a computer, a processor, a circuit board, a quantum circuit, or a semiconductor device. Each of the "~" units may use a common processing circuit (the same processing circuit) or different processing circuits (separate processing circuits). Information input and output to and from the pattern density calculation unit 50, dose calculation unit 52, temperature rise calculation unit 53, relationship data creation unit 54, combination acquisition unit 56 (reference stage speed calculation unit 57, combination calculation unit 58, writing time calculation unit 60, selection unit 61, comparison unit 62, combination determination unit 63, stage speed calculation unit 64, comparison unit 66, user information acquisition unit 67, judgment unit 68, and judgment unit 69), writing data processing unit 70, data processing unit 71, writing control unit 72, and transfer processing unit 74, as well as information being calculated, are stored in memory 112 each time.

[0088] FIG. 18 is a flowchart showing an example of some of the main steps of the writing method according to the second embodiment. FIG. 19 is a flowchart showing an example of the remaining main steps of the writing method according to the second embodiment. 18 and 19 are the same as those in FIG. 9 except that a stage velocity Vstage calculation step (S114), a comparison step (S115), a user information acquisition step (S116), a judgment step (S117), a combination determination step (S118), and a judgment step (S119) have been added as internal steps of the combination acquisition step (S110), and that the result of the judgment step (S119) determines whether the combination calculation step (S120), the drawing time calculation step (S122), the selection step (S124), and the comparison step (S126) are to be performed.

[0089] The contents of each step from the pattern density calculation step (S102) to the relational data creation step (S108) are the same as those in the first embodiment.

[0090] In the combination acquisition step (S110), the combination acquisition unit 56 reads out relational data from, for example, the storage device 144, and uses the relational data to acquire a stage speed at which the rise in temperature of the resist is equal to or less than a preset allowable rise in temperature. Specifically, the operation is as follows.

[0091] The content of the reference stage velocity calculation step (S112) is the same as in the first embodiment.

[0092] In the stage velocity Vstage calculation step (S114), when the multiplicity of multiple writing is predetermined, the stage velocity calculation unit 64 reads out relational data, for example, from the storage device 144, and uses the relational data to calculate, as the stage velocity Vstage, the maximum stage velocity that will result in an allowable temperature rise based on the predetermined multiplicity and resist sensitivity. The calculation method is the same as the method used by the combination acquisition unit 56 to calculate the maximum stage velocity Vstage in Case 1 of the first embodiment.

[0093] In the comparison step (S115), the comparison unit 66 compares the calculated stage velocity Vstage with a reference stage velocity V0 at a preset multiplicity. If the comparison result shows that the calculated stage velocity Vstage is equal to or greater than the reference stage velocity V0, the process proceeds to a combination determination step (S128). If the comparison result shows that the calculated stage velocity Vstage is smaller than the reference stage velocity V0, information indicating that the calculated stage velocity Vstage is smaller than the reference stage velocity V0 is output to the user, and the process proceeds to a user information acquisition step (S116). For example, this information may be displayed on a touch panel (not shown), or may be output externally.

[0094] In the user information acquisition step (S116), the user information acquisition unit 67 acquires from the user information indicating whether or not to draw at the calculated stage speed Vstage, and information indicating whether or not to change the degree of multiplicity (number of passes) of multiple drawing if drawing is not performed at the calculated stage speed Vstage. For example, selection buttons or the like are displayed on a touch panel or the like (not shown) to allow the user to make a selection.

[0095] In the determination step (S117), the determination unit 68 determines whether or not to draw at the calculated stage velocity Vstage, based on the information acquired from the user. If drawing is to be performed at the calculated stage velocity Vstage, the process proceeds to the combination determination step (S128). If drawing is not to be performed at the calculated stage velocity Vstage, the process proceeds to the determination step (S119).

[0096] In the user information acquisition step (S116), if drawing is not performed at the calculated stage speed Vstage, it is also preferable to acquire information indicating that drawing is not possible instead of information indicating whether to change the multiplicity (number of passes) of multiple drawing. In such a case, if drawing is not performed at the calculated stage speed Vstage, drawing is deemed to be impossible and drawing is stopped (dotted line).

[0097] In the combination determination step (S118), if the calculated stage velocity Vstage is equal to or less than the reference stage velocity V0, the combination determination unit 63 determines the combination to be used as the writing condition to be a combination of a preset multiplicity and stage velocity Vstage. If the calculated stage velocity Vstage is equal to or greater than the reference stage velocity V0, the combination to be used as the writing condition to be a combination of a preset multiplicity and reference stage velocity V0. Then, the process proceeds to the shot data generation step (S130).

[0098] In the determination step (S119), the determination unit 69 determines whether or not to change the degree of multiplicity (number of passes) of multiple drawing in accordance with information acquired from the user. If the degree of multiplicity (number of passes) of multiple drawing is to be changed, the process proceeds to the combination calculation step (S120). The combination calculation step (S120) through the combination determination step (S128) are carried out using the method of Case 2 in the first embodiment. Thereafter, the process proceeds to the shot data generation step (S130). If the degree of multiplicity (number of passes) of multiple drawing is not to be changed, the drawing is deemed impossible and is stopped.

[0099] The contents of each step after the shot data generation step (S130) are the same as those in Embodiment 1. Therefore, when a preset multiplicity is used, the drawing mechanism 150 draws a pattern on the substrate 101 placed on the XY stage 105 using the multibeams 20 while moving the stage at a stage speed according to the relationship between the reference stage speed V0 and the acquired stage speed Vstage.

[0100] As described above, according to the second embodiment, it is possible for the user to select to stop rendering and / or to change the multiplicity (number of paths).

[0101] Although the embodiments have been described above with reference to specific examples, the present invention is not limited to these specific examples. Furthermore, the processing functions described in embodiment 1 may be executed by a computer, and a program for causing a computer to execute such processing functions may be stored in a non-transitory, tangible readable recording medium such as a magnetic disk device.

[0102] Although the description of the device configuration, control method, and other parts not directly necessary for the explanation of the present invention have been omitted, the required device configuration and control method can be appropriately selected and used. For example, the description of the control unit configuration that controls the drawing device 100 has been omitted, but it goes without saying that the required control unit configuration can be appropriately selected and used.

[0103] In at least one of the above-described embodiments, the multi-charged particle beam drawing apparatus a storage device that stores data relating to the relationship between the stage speed of a stage on which a substrate coated with resist is placed, the dose per one lithography process in multiple lithography, and the temperature rise of the resist; a combination acquisition circuit that reads out the relational data from the storage device and acquires a combination of a stage speed capable of writing and a degree of multiplicity in multiple writing, which allows the temperature rise of the resist to fall within a tolerable temperature rise range, using the relational data; a drawing mechanism including a stage and an optical system that generates a multi-charged particle beam and controls the trajectory of the multi-charged particle beam, and that draws a pattern on a substrate placed on the stage by using the multi-charged particle beam through a drawing process that corresponds to a combination of the acquired stage speed and multiplicity; The present invention is characterized by the following.

[0104] The readable recording medium in at least one of the above-described embodiments includes: a process of storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with a resist in multi-beam lithography, the dose per lithography process in multiple lithography, and the temperature rise of the resist in a storage device; a process of reading the relationship data from the storage device, and using the relationship data to obtain a combination of a stage speed capable of writing and a multiplicity in the multiple writing, which allows the temperature rise of the resist to fall within a tolerable temperature rise range, and outputting the combination; The program for causing a computer to execute the above is recorded non-temporarily.

[0105] In addition, the multi-charged particle beam writing method in at least one of the above-described embodiments includes: storing, in a storage device, relationship data between a stage speed of a stage on which a resist-coated substrate is placed, a dose amount per one drawing process, and an increase in temperature of the resist, for drawing the substrate with a charged particle beam while moving the stage; reading the relationship data from the storage device, and using the relationship data, acquiring a stage speed at which the rise in temperature of the resist is equal to or less than a preset allowable rise in temperature; drawing a pattern on the substrate placed on the stage using multiple charged particle beams while moving the stage at a stage velocity according to the relationship between a reference stage velocity and the acquired stage velocity; It is characterized by:

[0106] Furthermore, the stage velocity acquisition device in at least one of the above-described embodiments includes: 1. An apparatus for acquiring a stage velocity for performing drawing on a substrate with a resist applied thereon by using a charged particle beam while moving a stage on which the substrate is placed, the apparatus comprising: a storage device that stores data relating to the relationship between the stage speed, the dose per drawing process, and the temperature rise of the resist; a stage speed acquisition circuit that reads the relationship data from the storage device and acquires a stage speed that causes the temperature rise of the resist to be equal to or lower than a preset allowable temperature rise, using the relationship data; The present invention is characterized by the following.

[0107] Furthermore, the multi-charged particle beam drawing apparatus in at least one of the above-described embodiments includes: a storage device that stores data relating to the relationship between the stage speed of a stage on which a substrate coated with a resist is placed, the dose per drawing process, and the temperature rise of the resist; a stage speed acquisition circuit that reads the relationship data from the storage device and acquires a stage speed that causes the temperature rise of the resist to be equal to or lower than a preset allowable temperature rise, using the relationship data; a drawing mechanism that draws a pattern on the substrate placed on the stage using multiple charged particle beams while moving the stage at a stage velocity according to a relationship between a reference stage velocity and the acquired stage velocity; The present invention is characterized by the following.

[0108] Furthermore, the readable recording medium in at least one of the above-described embodiments is a process of storing, in a storage device, relationship data between a stage speed of a stage on which a resist-coated substrate is placed, a dose amount per one writing process, and a temperature rise of the resist, for writing on the substrate with a charged particle beam while moving the stage; a process of reading the relationship data from the storage device, and using the relationship data, obtaining and outputting a stage speed at which the temperature rise of the resist is equal to or lower than a preset allowable temperature rise; The program for causing a computer to execute the above is recorded non-temporarily.

[0109] Furthermore, the readable recording medium in at least one of the above-described embodiments is a process of storing, in a storage device, relationship data between a stage speed of a stage on which a resist-coated substrate is placed, a dose amount per one writing process, and a temperature rise of the resist, for writing on the substrate with a charged particle beam while moving the stage; a process of reading the relationship data from the storage device and using the relationship data to obtain a stage speed at which the temperature rise of the resist is equal to or lower than a preset allowable temperature rise; a process of drawing a pattern on the substrate placed on the stage using multiple charged particle beams while moving the stage at a stage velocity according to the relationship between a reference stage velocity and the acquired stage velocity; The program for causing a computer to execute the above is recorded non-temporarily.

[0110] In addition, all stage velocity acquisition methods, stage velocity acquisition devices, multi-charged particle beam drawing devices, multi-charged particle beam drawing methods, methods for acquiring a combination of stage velocity and multiplicity in multi-charged particle beam drawing, and programs (or readable recording media on which programs are non-temporarily recorded) that include elements of the present invention and can be appropriately modified by a person skilled in the art are included in the scope of the present invention. [Explanation of symbols]

[0111] 20 Multibeam 22 holes 24 control electrode 25 Passing hole 26 Counter electrode 29 Sub-irradiation area 30 drawing area 32 stripe area 36 pixels 34 Irradiation area 41 Control circuit 50 Pattern density calculation unit 52 Dose calculation unit 53 Temperature rise calculation section 54 Relationship Data Creation Department 56 Combination acquisition unit 57 Reference stage speed calculation unit 58 Combination Calculation Unit 60 Drawing time calculation unit 61 Selection section 62 Comparison section 63 Combination determination unit 64 Stage speed calculation unit 66 Comparison section 67 User information acquisition unit 68 Judgment section 69 Judgment section 70 Drawing data processing unit 71 Data Processing Department 72 Drawing control unit 74 Transfer Processing Unit 100 drawing device 101 Substrate 102 Electron Telescope 103 Drawing room 105 XY stage 110 Control computer 112 memory 130 Deflection control circuit 132,134 DAC amplifier unit 136 Lens control circuit 138 Stage Control Mechanism 139 Stage Position Measuring Instrument 140,142,144 Storage device 150 Drawing mechanism 160 Control Circuits 200 electron beam 201 Electron Gun 202 Lighting lens 203 Shaped Aperture Array Substrate 204 Blanking Aperture Array Mechanism 205 Reduction Lens 206 Limiting Aperture Substrate 207 Objective Lens 208 Deflector 209 Deflector 210 Mirror 330 Membrane Region

Claims

1. 1. A method for acquiring a stage velocity for performing drawing on a substrate coated with a resist with a charged particle beam while moving a stage on which the substrate is placed, the method comprising: storing data relating to the relationship between the stage speed, the dose per drawing process, and the temperature rise of the resist in a storage device; a processing circuit reading out the relationship data from the storage device, and using the relationship data, obtaining and outputting a stage speed at which the temperature rise of the resist is equal to or lower than a preset allowable temperature rise; A stage velocity acquisition method comprising:

2. acquiring a stage velocity by the stage velocity acquisition method of claim 1; drawing a pattern on the substrate placed on the stage using multiple charged particle beams while moving the stage at a stage velocity according to the relationship between a reference stage velocity and the acquired stage velocity; A multi-charged particle beam writing method comprising:

3. If the reference stage speed is faster than the acquired stage speed, it is determined that drawing is not possible.

3. A multi-charged particle beam writing method according to claim 2.

4. calculating a maximum stage speed within a range where drawing processing is possible as the reference stage speed; 3. A multi-charged particle beam writing method according to claim 2.

5. When the degree of multiplicity of multiple writing is predetermined, a stage speed at which the temperature rise of the resist falls within an allowable temperature rise based on the determined degree of multiplicity and resist sensitivity is acquired as the stage speed using data relating to the stage speed, the dose per writing process, and the temperature rise of the resist; the pattern is drawn on the substrate by a drawing process using a predetermined multiplicity and the acquired stage speed; 3. A multi-charged particle beam writing method according to claim 2.

6. storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with a resist, the dose per one lithography process in multiple lithography, and the temperature rise of the resist in a storage device; reading the relationship data from the storage device, and using the relationship data, obtaining a combination of a stage speed capable of writing and a multiplicity in the multiple writing, which allows the temperature rise of the resist to fall within an allowable temperature rise range; using multiple charged particle beams, a pattern is drawn on the substrate placed on the stage through a drawing process according to the combination of the acquired stage speed and multiplicity; A multi-charged particle beam writing method comprising:

7. 7. The multi-charged particle beam writing method according to claim 6, wherein the temperature rise of the resist is calculated for each of a plurality of mesh regions into which a writing region irradiated with the multi-charged particle beam is divided, based on a representative value of a dose amount of the beam irradiating the mesh region, a speed of the stage, and a size of the irradiation region of the multi-charged particle beam in the writing progress direction.

8. Calculating a maximum temperature rise of the resist by varying the total dose of the irradiation area of ​​the multi-charged particle beam and the stage speed; creating the relationship data using the calculated maximum temperature rise of the resist; 7. A multi-charged particle beam writing method according to claim 6.

9. 7. A multi-charged particle beam writing method according to claim 6, wherein a temperature rise lower than the melting temperature of the resist is used as the allowable temperature rise.

10. 7. A multi-charged particle beam writing method according to claim 6, wherein the allowable temperature rise is a temperature rise at which the dimensional accuracy of the pattern to be written is allowable.

11. the multiplicity of the combinations of the stage speed and the multiplicity is set in advance; Obtaining the combination includes:

7. A multi-charged particle beam writing method according to claim 6, wherein the maximum stage speed at which writing can be performed within the allowable temperature rise is calculated based on a preset multiplicity and exposure sensitivity of the resist, using the relationship data.

12. Obtaining the combination includes: calculating a plurality of combinations of the stage speed and the multiplicity according to the exposure sensitivity of the resist; selecting a combination that shortens the drawing time from the plurality of combinations; 7. A multi-charged particle beam writing method according to claim 6.

13. storing data relating to the relationship between the stage speed of a stage for placing a substrate coated with a resist, the dose per one lithography process in multiple lithography, and the temperature rise of the resist in a storage device; reading the relationship data from the storage device, and using the relationship data, obtaining a combination of a stage speed capable of writing and a multiplicity in the multiple writing, which allows the temperature rise of the resist to fall within an allowable temperature rise range, and outputting the combination.

2. A method for obtaining a combination of stage speed and multiplicity in multi-charged particle beam writing, comprising:

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