JP2000243685A - Drafting method and apparatus by using charged-particle beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the calculation amount in the case of an electron beam shot, by creating the distribution table of the accumulation energy of each partition which is calculated when an electron beam is projected on a point of a drawing region, by memorizing an energy map whereto the accumulation energy rewritten by the area ratio of a divided pattern to each partition is added, and further, by correcting a beam-shot time through using the energy map. SOLUTION: The whole region of a drawn material is partitioned sectionally into the identical partitions with the ones of an energy map. By the command of a CPU 14, in a second diagram dividing circuit 16, a drafting pattern data obtained from a data memory 13 is divided into the partitions of the energy map. The data of the height and width of each divided pattern are sent successively to a multification circuit 18 of an energy-map creating circuit 17. By the command of the CPU 14, the table of a reference energy distribution map is called from an integrated memory 21. Each energy value of the energy distribution table is rewritten by the area data of each divided pattern to create the energy table of each partitioned pattern. By the positional data obtained from the second diagram dividing circuit 16, the energy distribution data of the divided pattern is added to the energy distribution data read from the memory 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charged particle beam writing method for writing a pattern by correcting the influence of a proximity effect.

[0002]

2. Description of the Related Art In an electron beam writing method, a resist is applied on a substrate, and an electron beam is shot at a predetermined position on such a material to be drawn to form a predetermined pattern at a predetermined position on the material to be drawn. This is a drawing method, and an extremely dense semiconductor element can be manufactured.

In such an electron beam writing method, the shot electron beam scatters in the resist (referred to as forward scattering), passes through the resist, enters the substrate, and again scatters from the substrate into the resist. (Referred to as backscattering), energy is accumulated in a portion other than the shot region. Therefore, when development is performed, a phenomenon occurs in which an unexposed portion occurs in a predetermined region or a portion other than the predetermined region is exposed. Such a phenomenon is referred to as a proximity effect. A phenomenon caused by pattern drawing of the pattern itself is referred to as an intra-pattern proximity effect, and a phenomenon caused by drawing another pattern at a close position is referred to as an inter-pattern proximity effect.

[0004]

In order to reduce the influence of the proximity effect, the shot time is changed in accordance with the size of the pattern to be drawn or the distance between adjacent patterns. Therefore, in advance, a shot time correction amount based on the size of the pattern to be drawn itself,
Calculate the shot time correction amount based on the interval between adjacent patterns, and have it as proximity effect correction data for each pattern to be drawn, and use the proximity effect correction data at the time of drawing each pattern to reduce the influence of the proximity effect. To perform pattern drawing.

However, in recent years, the degree of integration of patterns has become extremely high, and as a result, the amount of calculation has become enormous.
This hinders the improvement of the pattern drawing throughput.

The object of the present invention is to solve such a problem.

[0007]

Means for Solving the Problems A charged particle beam drawing method according to the present invention is a charged particle beam drawing method for drawing a drawing pattern on a material to be drawn by shots of the charged particle beam. Dividing into a plurality of sections, calculating the stored energy in each section when an electron beam is shot at one point on the drawing area, creating a reference stored energy distribution table, and dividing the drawing pattern into a plurality of pieces in the same manner as the division. , And for each of one or more divided patterns in each of the sections generated by the division, an area ratio of the divided pattern in the section is determined. Further, the reference stored energy is determined based on the ratio. The stored energy of each section of the distribution table is rewritten, and the stored energy rewritten for each of the divided patterns is sequentially stored in the same section. Each time, an energy map is created and stored in a memory.At the time of drawing a divided pattern, the stored energy value of a section where the divided pattern exists is called from the memory, and the shot time is corrected based on the stored energy value. A divided pattern is drawn on the material to be drawn by a shot of a charged particle beam.

In the charged particle beam writing method according to the present invention, a pattern is drawn for each small area in a writing area composed of a plurality of small writing areas. In this case, a plurality of memories for storing energy maps are prepared. Then, an energy map is created for one small drawing area, and the map is stored in any memory. Then, an energy map is created for each of the other small drawing areas, and the map is stored immediately before. The step of storing data in any memory other than the specified memory and the step of drawing a pattern of a small drawing area for which an energy map has been created are performed in parallel.

The charged particle beam drawing method according to the present invention is characterized in that the small drawing region is a region in which a pattern can be drawn only by deflection of the charged particle beam within an allowable deflection error.

A charged particle beam drawing apparatus according to the present invention is a charged particle beam drawing apparatus configured to draw a drawing pattern on a material to be drawn by a shot of the charged particle beam. Means for calculating the stored energy in each section when the electron beam is shot at one point on the drawing area by dividing the section into sections, and creating a reference stored energy distribution table; a first memory for storing the reference stored energy distribution table A figure dividing circuit for dividing the drawing pattern into a plurality of sections in the same manner as the division, an area calculating circuit for calculating an area of each of one or more divided patterns in each section generated by the division; The ratio between the area of the divided pattern thus obtained and the section area is determined, and based on the ratio, each of the reference stored energy distribution tables Dividing pattern accumulating energy distribution table creation circuit for rewriting the image stored energy,
An adding circuit for sequentially adding the stored energy rewritten for each of the divided patterns to each of the same sections, a second memory for storing a total stored energy distribution based on an output of the adding circuit as an energy map, and drawing from the second memory A shot time control circuit that calls a stored energy value of a section where a divided pattern to be present exists, and corrects a shot time based on the stored energy value, and draws a divided pattern on a material to be drawn by a shot of a charged particle beam. A charged particle beam optical means, a shot time based on the shot time corrected by the shot time control circuit, a divided pattern is drawn on the material to be drawn by squatting the charged particle beam. Features.

A charged particle beam drawing apparatus according to the present invention comprises a charged particle beam generating means, a charged particle beam cross section varying means having a plurality of slits and a beam cross section deflector therebetween, and a charged particle beam cross section varying means. A positioning deflector for causing the beam to be shot at a predetermined position on the material to be drawn, a data memory storing the drawing pattern data, and a method of dividing the drawing pattern from the data memory into a beam shot pattern. A first figure dividing circuit, wherein the positioning deflector is controlled based on shot position data constituting shot divided pattern data divided by the first figure dividing circuit, and based on pattern dimension data constituting the shot divided pattern data. Controlling the molding deflector by means of a charged particle beam A charged particle beam drawing apparatus configured to draw a pattern on a material to be drawn, wherein a drawing area on the material to be drawn is divided into a plurality of sections, and an electron beam is shot at one point on the drawing area. Means for calculating the stored energy in each section and creating a reference stored energy distribution table, a first memory storing the reference stored energy distribution table, and a first memory for dividing the drawing pattern into a plurality of sections in the same manner as the division. 2 figure division circuit,
An area calculating circuit for obtaining an area for each of one or more divided patterns in each of the sections generated by the division; a ratio between the calculated area of the divided pattern and the section area being determined; A divided pattern stored energy distribution table creation circuit for rewriting the stored energy of each section of the reference stored energy distribution table, an adding circuit for sequentially adding the stored energy rewritten for each of the divided patterns sequentially to the same section, and the addition A second memory that stores a total stored energy distribution based on an output of the circuit as an energy map, calls a stored energy value of a section where a shot division pattern exists from the second memory, and stores a shot corrected by the shot time control circuit. Time based shot time, charged particle beam shot and Characterized capital which forms as draw divided pattern on the drawing material by Rukoto.

A charged particle beam writing apparatus according to the present invention prepares a plurality of second memories and creates an energy map for one small writing area constituting the writing area.
After storing the map in any one of the memories, an energy map is created for each of the small drawing areas forming the other drawing area, and the map is stored in any of the memories other than the memory stored immediately before. The step of making the energy map and the step of drawing the pattern of each small drawing area for which an energy map has been created are performed in parallel.

A charged particle beam drawing apparatus according to the present invention is provided with one common figure division circuit, and the common figure division circuit can perform division of a drawing pattern and division of a shot size pattern of the drawing pattern alternately. In the former case, an energy map is created, and in the latter case, pattern drawing is performed.

In the charged particle beam drawing apparatus according to the present invention, when the size of the shot size pattern is larger than the section size of the energy map, the stored energy value of the center section among the plurality of sections related to the shot size pattern. , The shot time is corrected based on The charged particle beam writing apparatus according to the present invention corrects a shot time based on an average value of stored energy values of a plurality of sections related to the shot size pattern when the size of the shot size pattern is larger than the section size of the energy map. It is characterized by doing so.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an example of an electronic drawing apparatus for realizing an embodiment of an electron beam drawing method according to the present invention. In the figure, 1 is an electron gun, 2 is a blanking electrode, 3
Denotes a blanking slit, and 4 denotes an irradiation lens.
Reference numerals 5 and 6 denote a first forming slit and a second forming slit each having a polygonal shape, for example, a square or rectangular hole at the center, and 7 form an image of the hole of the first forming slit 5 on the second forming slit. Lens 8 for performing the first
A shaping deflector for deflecting the electron beam that has passed through the shaping slit to determine the image forming position of the first shaping slit hole image on the second shaping slit. , And the shaping deflector 8 constitute an electron beam cross-section variable mechanism. Reference numeral 9 denotes a converging lens for converging the electron beam passing through the second shaping lens 6 onto the material 10 to be drawn, and reference numeral 11 denotes a positioning deflector for determining the position of the electron beam converged on the material. . Reference numeral 12 denotes a stage on which the material to be drawn 10 is placed.

Reference numeral 13 denotes a memory in which data of a drawing pattern to be drawn on the material to be drawn is stored. Reference numeral 14 denotes a central control unit (hereinafter, referred to as a CPU).

Reference numeral 15 denotes a first figure dividing circuit,
A circuit for dividing the drawing pattern data from the data memory 13 into beam shot size data (that is, shot size pattern data) in accordance with the instruction of No. 4 by dividing the drawing pattern data, The beam shot position data is generated, and the former is used as the shaping deflector 8 and the latter is used as the positioning deflector 11 and the short time control circuit 2 described later.
Feed to 2.

Reference numeral 16 denotes a second figure dividing circuit,
In accordance with the instruction of No. 4, it is assumed that the drawing pattern data from the data memory 13 is converted into an energy map (to be described later, the entire drawing area on the material to be drawn is divided into a plurality of sections, and a predetermined pattern is drawn in all the drawing areas by electron beam shots). In this case, a circuit that divides the divided energy into a plurality of sections (calculated and mapped by the energy accumulated by the electron beam irradiation in each section) is used to form a pattern (hereinafter, referred to as a divided pattern) divided into each section. The position data and the data of the height and width of the divided pattern are generated.

Reference numeral 17 denotes an energy map creation circuit, which includes a multiplication circuit 18, a divided pattern energy distribution table creation circuit 19, and an addition circuit 20. The multiplication circuit 16
Is a circuit for calculating the area of the divided pattern divided into each section based on the height and width data of the divided pattern from the second figure dividing circuit 16. The divided pattern energy distribution table creation circuit 19 includes the multiplication circuit 1
Based on the area data of the divided pattern from No. 8, a reference energy distribution table (to be described later, the entire drawing area on the material to be drawn is divided into the same section as the section of the energy map,
Assuming that an electron beam shot is performed at one point at the center of the center section of the entire drawing area, in this case, the energy stored in each section is calculated and tabulated, and the energy value of each section is rewritten. This is a circuit for creating an energy distribution table of the divided pattern by performing the above operation. The addition circuit 20 adds the divided pattern energy distribution from the divided pattern energy distribution table creation circuit 19 to the energy distribution data read from the energy map memory 21 based on the position data of the divided pattern from the second figure division circuit 16. A circuit for adding data centering on the section where the divided pattern exists and returning (storing) the energy map memory 21 again.

Reference numeral 22 denotes a reference shot time determined by the sensitivity and thickness of the resist applied to the material to be drawn from the CPU 14 and is set based on a shot time correction coefficient from a correction table 23 described later. The blanking signal generation circuit 2 corrects the reference shot time
4 is a shot time control circuit which supplies the shot pattern data to the first figure division circuit 15 based on the shot position data.
This is a circuit for retrieving, from the energy map memory 21, a stored energy value of a section where a shot size pattern corresponding to a beam shot at that shot position exists. The correction table 23 is a table in which each stored energy value obtained in advance by an experiment or the like and a shot time correction coefficient corresponding to the stored energy value are tabulated, so that the stored energy value called from the energy map 21 is stored. Is sent to the shot time control circuit 22. The blanking signal generation circuit 24 is connected to the shot time control circuit 2
A blanking signal is created based on the shot time signal from the second deflector 2 and supplied to the blanking deflector 2.

Reference numeral 25 denotes a stage drive mechanism for controlling the movement of the stage in accordance with a command from the central control unit 14. 26, 27 and 28 are DA converters.

Next, an example of the electron beam writing method of the present invention will be described.

First, an energy map is created before actual pattern drawing starts, and the completed energy map is stored in the energy map memory 21. The creation of the energy map is performed as in the following (1) to (3).

(1) Create a reference energy distribution table.

First, the whole drawing area on the material to be drawn is divided into the same section as the section of the energy map. The size of this section is, for example, smaller than the extent of backscattering.

Next, assuming that an electron beam is shot at one point in the center section, the stored energy of each section in that case is calculated and tabulated. The calculation of such stored energy is performed as follows.

The energy stored at a position (x, y) at a certain depth from the resist surface when an electron beam is incident on one point is represented by EID (Energy Int) of the following equation (1).
It is calculated based on the function of the "Essence Distribution".

[0029]

(Equation 1) …… (1)

In this equation, β _f , β _b , and η are constants determined by the depth from the resist surface. Β _f is called the forward scattering diameter, β _b is called the back scattering diameter, and η is called the back scattering coefficient.
The first term on the right side of this equation is the distribution of energy accumulated when electrons entering the resist penetrate while scattered forward, and the second term is the backward distribution of the incident electrons by atomic nuclei in the resist and the substrate. Β _f and β _b are distributions of energy accumulated when receiving scattering and scattering in the direction opposite to the incident direction, wherein β _f and β _b are standard deviations of the respective Gaussian distributions.
Here, η is the ratio of the total energy stored in the resist due to forward scattering to the total energy stored in the resist due to back scattering. By such a calculation, the stored energy at a position (x, y) at a certain depth from the resist surface when the electron beam is incident on one point can be obtained, and the distribution of the total stored energy in each section is determined as a reference. The energy distribution is stored in an internal memory (not shown) of the divided pattern energy distribution table creating circuit 19. FIG. 2 is an example of a reference energy distribution table showing stored energy in each section.

(2) Pattern in each section (divided pattern)
Create an energy distribution table for

First, in response to a command from the CPU 14, the second
The figure dividing circuit 16 divides the drawing pattern data from the data memory 13 into sections of the energy map. For example, the pattern P _A in the drawing area, P _B, must be drawn significantly more drawing pattern if (actually draw P _C, for convenience of explanation, the pattern to be drawn P _A,
P _B, and a P _C), divides these drawing pattern data to the compartment and the same compartment of energy map. Figure 3 shows a state that is the divided, one section is greater than the pattern P _C is divided into _{P 1, P 2, P 3} , P 4, P 5, P 6, P 7, P 8, P 9 ing. Then, the second figure division circuit 16 calculates these division patterns P _A , P _B , P ₁ , P ₂ , P ₃ , P ₄ ,
The position data of P ₅ , P ₆ , P ₇ , P ₈ , P _{9 and} the data of height and width are generated.

Next, the height data and the width data of each of the divided patterns are sequentially sent to the multiplying circuit 18 of the energy map creating circuit 17. The multiplication circuit 18 calculates the area of the divided pattern divided into each section based on the height and width data of the divided pattern sent. For example, to calculate the area S _A from the height data and width data division pattern P _A.

Next, the reference energy is inputted according to a command from the CPU 14.
Energy distribution table is called from internal memory (not shown)
Divided pattern energy distribution table creation circuit 1
Reference numeral 9 denotes each of the divisions sequentially sent from the multiplication circuit 18.
Based on the pattern area data, the reference energy distribution
Rewrite the energy value of each section of the cable
Create an energy table for the pattern. For example, the square
Dividing pattern P from arithmetic circuit 18_AArea S_AData sent
The area S_OAnd division pattern P_AArea
S_A Is calculated and the reference distribution table is calculated according to the ratio.
Rewrite the stored energy value of each section. For example, the ratio
Is 1 / N, the stored energy of each section of the reference distribution table
-Rewrite all values to 1 / N. This rewritten version
FIG. 4 shows the energy distribution table of the division pattern.
Pattern P_A3 shows an energy distribution table.
Similarly, FIG._BDivision pattern P_BEnergy
Distribution table, FIG. 6 shows area S₁Division pattern P₁No
The respective energy distribution tables are shown. In addition, other
Division pattern P_Two, P_Three, P_Four, P_Five, P₆, P₇, P ₈, P₉
Energy distribution table is also created sequentially as above
Is done.

(3) Create an energy map.

The adder circuit 20 includes the second figure dividing circuit 1
6 is added to the energy distribution data read from the energy map memory 21 based on the position data of each divided pattern sequentially transmitted from 6 to the divided pattern energy distribution data sequentially transmitted from the divided pattern energy distribution table creation circuit 19. The operation of adding the segment based on the position data of each of the divided patterns, that is, the segment where the divided pattern exists, and returning (storing) the energy map memory 21 again is repeated.

For example, the divided pattern P_ALocation data
(X_A, Y_A) From the energy map memory 21
The energy distribution data is output to the adding circuit 20. The addition
Calculation circuit 20 creates divided pattern energy distribution table
Divided pattern P sent from circuit 19_ASplit pattern
Energy energy distribution data to the divided pattern P_ARank
Data (X_A, Y_A), The divided pattern exists
From the energy map memory 21 focusing on the section to be
Add to the read energy distribution data and add
It is returned (stored) to the energy map memory 21. Sequentially
And the division pattern P _BPosition data (X_B, Y_BBy)
Energy read from energy map memory 21
-Energy distribution table creation circuit 19 for distribution data
Pattern P sent from_BDivided pattern energy
The distribution pattern of the split pattern P_BPosition data
(X_B, Y_B) Based on the division pattern
Read from the energy map memory 21
The energy map is added to the energy distribution data
To the memory 21 (store). After that, the same operation
Repeatedly, each divided pattern P_A, P_B, P₁, P_Two, P
_Three, P_Four, P_Five, P₆, P₇, P₈, P₉Energy distribution
Data based on the position data of each of the divided patterns.
The error added around the section where the division pattern exists
The energy map is completed and the energy map memory 21
Is stored. The energy map completed in this way
Electronically prints all drawing patterns at predetermined positions in the drawing area.
Forward scattering of each section when drawn by beam shot
Energy considering the energy stored by backscattering
Corresponding to the expression of the energy.

Next, the actual pattern drawing will be described.

[0039] For example, the case of drawing a division pattern P _A shown in FIG. 2 on the drawing material.

The data memory 13 contains, for example, a file.
Field (within the range of allowable deflection error only by electron beam scanning)
Drawing pattern divided into units)
Data is stored. For convenience of explanation,
Turn P_AIs a pattern drawn in the field F1.
Then, the position data of the field F1 and the field F
Drawing pattern P based on position 1_APosition and size
Data is stored in advance. The CPU 14 controls the
From the memory 13 to the position data and the drawing pattern of the field F1
P_ACall the position and size data. And
The position signal of the field F1 is scanned via the DA converter 28.
It is sent to the stage driving mechanism 25. Drawing pattern P_ARank
(X_A, Y_A) And size data (H_A, W_AFigure 1)
It is input to the shape dividing circuit 15. The first figure division circuit includes:
Drawing pattern P_AData of the maximum shot beam size
In consideration of the above, for example, as shown in FIG.
I do. The shot size divided into these shot sizes
Is the pattern of P_A1, P _A2, P_A3, P_A4, P_A5, P_A6
And The first figure division circuit is configured to generate each figure generated by the division.
Shot size pattern size data and its position data
The shot time control circuit 22 and the former
The latter is supplied to the shaping deflector 8 and the latter to the positioning deflector 11.
Pay. For example, a shot size pattern P_A1Position of
When the data is sent to the shot time control circuit 22,
The control circuit determines the energy based on the shot position data.
Shot from the gimmap memory 21 to that shot position
Shot size corresponding to the shot size beam
Pattern P_A1 Of the section where section exists (section KA in FIG. 3)
Call the energy value. The called energy value is
The correction table is sent to the correction table 23, and the
The shot time correction coefficient corresponding to the
The time is transmitted to the time control circuit 22. The shot time control times
The road 22 is based on the reference sent from the CPU 14.
The shot time is compensated based on the shot time correction coefficient.
The corrected shot time signal is converted to a blanking signal generation circuit 2
4 The blanking signal generating circuit 24
Create a blanking signal based on the
It is supplied to the blanking deflector 2.

As a result, the electron beam from the electron gun 1
The cross section size is reduced by the
Division pattern P_A1Molded to correspond to the dimensional data of
The shaped beam is moved by the deflector 11 for positioning.
The time based on the blanking signal, the shot division
Turn P_A1To the position of the drawing material corresponding to the position data of
Shot, shot division pattern P_A1Is drawn
You. Thereafter, the drawing pattern P _AShot size putter
P_A2, P_A3, P_A4, P_A5, P_A6 Are all sections KA
Because the pattern is inside_A1Same energy as in
When a value is called and a shot based on the same correction factor
During a short time, and as a result, the drawing pattern
P_AWill be drawn. Thereafter, in the same manner,
P_B, P₁, P_Two, P_Three, P_Four, P_Five, P₆, P₇, P₈,
P₉Is drawn.

In the above embodiment, the case where one division pattern exists in each section has been described. However, when a plurality of division patterns exist in a section, the stored energy distribution for each division pattern is determined. Tables are created at different times.

Actually, the memory 13 stores drawing pattern data covering a large number of fields.
When the drawing of the graphic pattern of one field is completed, the position data of the next field is sent from the central control unit 14 to the stage driving mechanism 25 via the DA converter 28, and each drawing pattern data of the field is transmitted as described above. Drawing is performed in the same manner as described above.

In the above-described embodiment, before starting pattern drawing, an energy map is created for all the drawing patterns drawn in the drawing area on the drawing area, and the energy map is used at the time of actual pattern drawing. However, a plurality of energy map memories (for example, two) are prepared, and the energy map is created and stored in the memory and the pattern drawing is performed in parallel for each small drawing area. You may do it. That is, only in the first time, the energy map of the first small drawing area is created and stored in the first energy map.
The pattern drawing of the first small drawing area using the first energy map is performed while the energy map of the small drawing area is created and stored in the second energy map. While creating the energy map of the drawing area and storing it in the first energy map,
The pattern drawing of the second small drawing area is performed using the energy map of the second step. In the fourth time, the energy map of the fourth small drawing area is created and stored in the second energy map. , The pattern drawing of the third small drawing area using the first energy map is performed. By doing so, the time required to create the energy map for the entire drawing area is apparently the time required to create the energy map for the first small drawing area, and the throughput of pattern drawing is greatly improved. The small drawing region may be, for example, a field (a region where pattern drawing can be performed only by electron beam deflection within an allowable deflection error without moving the stage), but is not limited to this.

In the above embodiment, two figure division circuits for shot size division and energy map section division are provided. However, the figure division circuit is made into one, and the drawing pattern is divided into energy map sections. One (common) figure dividing circuit may be used alternately when creating an energy map or when dividing a drawing pattern into shot sizes and performing pattern drawing.
In this case, only one relatively large figure dividing circuit is required, which is advantageous in terms of space and cost.

In the above embodiment, the shot size is smaller than the section of the energy map. However, if the shot size is larger than the section of the energy map, and the shot size extends over a plurality of sections, Of these, the stored energy value of the central section is used for the proximity effect correction. In this case, an average value of the stored energy values of a plurality of sections may be used.

Although the above embodiment has been described by taking an electron beam drawing apparatus as an example, it goes without saying that the present invention is also applicable to an ion beam drawing apparatus.

According to the present invention, a drawing area on a material to be drawn is divided into a plurality of sections, and the stored energy in each section when an electron beam is shot at one point on the drawing area is calculated to obtain a reference stored energy distribution table. Is created, and the drawing pattern is divided into a plurality of sections in the same manner as the division,
For each of one or more divided patterns in each section generated by the division, a ratio between the area of the divided pattern and the section area is obtained, and further, each of the reference stored energy distribution tables in the reference stored energy distribution table is determined based on the ratio. The stored energy of the section is rewritten, and the stored energy rewritten for each of the divided patterns is sequentially added for each of the same sections to form an energy map and stored in the memory. When the divided pattern is drawn, the divided pattern is read from the memory. Is called, and the shot time is corrected based on the stored energy value, and the divided pattern is drawn on the material to be drawn by the shot of the charged particle beam. Shot time correction amount based on the size of the shot and shot time based on the distance between adjacent patterns A positive value is calculated and provided as proximity effect correction data of each pattern to be drawn, and at the time of drawing each pattern, the effect of the proximity effect is reduced using the proximity effect correction data to perform pattern drawing. . Therefore, even if the degree of pattern integration becomes extremely high,
Since it is not necessary to calculate proximity effect correction data for each pattern and to provide the data as data, the throughput of pattern drawing is significantly improved.

After the reference stored energy distribution table is created as in the above embodiment, the drawing pattern is divided into sections corresponding to the sections of the energy map, and the stored energy distribution table for each divided pattern is created sequentially. Instead of creating an energy map by adding the accumulated energy distributions of the sequentially created divided patterns, the drawing pattern is divided into sections corresponding to the sections of the energy map, and each of the sections is present in each section. The areas of the divided patterns are summed up, the pattern area ratio of each section is calculated, a pattern area ratio distribution table is created once, the pattern area ratio distribution table is extended, and then the reference stored energy table There is also a method of creating an energy map by knocking the extended pattern area ratio distribution table and the extended pattern area ratio distribution table. That's method, to be drawn pattern is pattern area ratio distribution table beginning to Desoro' all be ready, as compared to the former embodiment, takes more time until the energy map is completed. That is, in the above-described embodiment, it is not necessary for all the patterns to be drawn to come out, and the stored energy distribution tables for the sequentially divided patterns are created and sequentially added, so that the energy map is created very quickly.

[Brief description of the drawings]

FIG. 1 shows an example of an electronic drawing apparatus for realizing an embodiment of an electron beam drawing method according to the present invention.

FIG. 2 shows an example of a reference stored energy distribution table according to the present invention.

FIG. 3 shows an example in which a drawing pattern is divided into the same sections as the sections of the energy map.

FIG. 4 shows an example of a stored energy distribution table of a divided pattern.

FIG. 5 shows an example of a stored energy distribution table of a divided pattern.

FIG. 6 shows an example of a stored energy distribution table of a divided pattern.

FIG. 7 shows an example in which a division pattern is divided into shots.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electron gun, 2 ... Blanking electrode, 3 ... Blanking slit, 4 ... Irradiation lens, 5 ... 1st shaping slit, 6 ... 2nd shaping slit, 7 ... Shaping lens, 8 ... Shaping deflector, 9: Focusing lens, 10: Material to be drawn, 11 ...
Positioning deflector, 12 stage, 13 data memory, 14 central control unit, 15 first figure division circuit, 1
6: 2nd figure division circuit, 17: energy map creation circuit, 18: multiplication circuit, 19: division pattern energy distribution table creation circuit, 20: addition circuit, 21: energy map memory, 22: shot time control circuit, 23 ...
Correction table, 24 ... Blanking signal generation circuit, 25
... Stage drive mechanism, 26,27,28 ... DA converter

Claims (9)

[Claims] In a charged particle beam drawing method for drawing a drawing pattern on a material to be drawn by a shot of a charged particle beam, a drawing area on the material to be drawn is divided into a plurality of sections, and an electron is assigned to one point on the drawing area. Calculate the stored energy in each section when the beam is shot, create a reference stored energy distribution table, divide the drawing pattern into a plurality of sections in the same manner as the division, and generate For each of the one or more divided patterns, an area ratio occupied by the divided pattern in the section is determined, and further, the stored energy of each section of the reference stored energy distribution table is rewritten based on the ratio, and The stored energy rewritten for each pattern is sequentially added for each section to create an energy map and store it in the memory. At the time of drawing the divided pattern, the stored energy value of the section where the divided pattern exists is called from the memory, the shot time is corrected based on the stored energy value, and the divided pattern is drawn on the material to be drawn by the shot of the charged particle beam. Charged particle beam drawing method. 2. A drawing area comprising a plurality of small drawing areas,
A pattern is drawn for each of the small regions. In this case, a plurality of memories for storing energy maps are prepared, an energy map for one small drawing region is created, and the map is stored in any one of the memories. After that, a step of creating an energy map for each of the other small drawing areas and storing the map in any memory other than the memory stored immediately before, and a step of forming a pattern of the small drawing area for which the energy map has been created. 2. The charged particle beam writing method according to claim 1, wherein the step of writing is performed in parallel. 3. The charged particle beam drawing method according to claim 2, wherein the small drawing region is a region where a pattern can be drawn only by deflection of the charged particle beam within an allowable deflection error. 4. A charged particle beam drawing apparatus configured to draw a drawing pattern on a material to be drawn by a shot of a charged particle beam, wherein a drawing area on the material to be drawn is divided into a plurality of sections, Means for calculating the stored energy in each section when an electron beam is shot at one point, creating a reference stored energy distribution table, a first memory storing the reference stored energy distribution table, and dividing the drawing pattern into the same as the division Dividing circuit for dividing into a plurality of sections as described above, an area calculating circuit for calculating an area of each of one or more divided patterns in each section generated by the division, an area of the calculated divided pattern and the section A division pattern for determining a ratio to the area and rewriting the stored energy of each section of the reference stored energy distribution table based on the ratio. A stored energy distribution table creating circuit, an adding circuit for sequentially adding the stored energy rewritten for each of the divided patterns sequentially to the same section, and a total storing energy distribution based on the output of the adding circuit as an energy map. A second memory, a stored energy value of a section where a divided pattern to be drawn exists from the second memory, a shot time control circuit for correcting a shot time based on the stored energy value, and a charged particle beam shot. Equipped with charged particle beam optical means for drawing a division pattern on the drawing material,
A charged particle beam drawing apparatus configured to draw a divided pattern on a material to be drawn by making a charged particle beam short for a shot time based on the shot time corrected by the shot time control circuit. 5. A charged particle beam generating means having a plurality of slits and a deflector for shaping a beam cross section between the slits, and a beam formed by the charged particle beam changing means is provided on a material to be drawn. A positioning deflector for causing a shot at a predetermined position, a data memory storing drawing pattern data, and a first figure dividing circuit for dividing a drawing pattern from the data memory into a beam shot pattern; The positioning deflector is controlled based on shot position data constituting shot divided pattern data divided by the one figure dividing circuit, and the forming deflector is controlled based on pattern dimension data constituting the shot divided pattern data. This makes it possible to draw a pattern on the material to be drawn with a charged particle beam. A charged particle beam writing apparatus, wherein a drawing area on a material to be drawn is divided into a plurality of sections, and the energy stored in each section when an electron beam is shot at one point on the drawing area is calculated. Means for creating an energy distribution table, a first memory for storing the reference accumulated energy distribution table, a second figure division circuit for dividing the drawing pattern into a plurality of sections in the same manner as the division, and each section generated by the division An area calculation circuit for obtaining an area for each of one or more of the divided patterns, a ratio between the calculated area of the divided pattern and the divided area, and the ratio of the reference stored energy distribution table based on the ratio. A divided pattern stored energy distribution table creating circuit for rewriting the stored energy of each section, which is sequentially rewritten for each divided pattern. Adder circuit for adding the stored energy for each sequential same partition, and a second memory for storing a total accumulated energy distribution based on the output of said adder circuit as an energy map, the second
Calling the stored energy value of the section where the shot division pattern exists from the memory, a shot time based on the shot time corrected by the shot time control circuit,
A charged particle beam drawing apparatus configured to draw a divided pattern on a material to be drawn by using a charged particle beam as a shot. 6. A method according to claim 6, further comprising preparing a plurality of second memories, creating an energy map for one small drawing area forming the drawing area, storing the map in any one of the memories, and then executing the other drawing. Creating an energy map for each of the small drawing areas forming the area, storing the map in any memory other than the memory stored immediately before, and drawing the pattern of each of the small drawing areas for which the energy map has been created. The charged particle beam drawing apparatus according to claim 4 or 5, wherein the step of performing is performed in parallel. 7. A common graphic dividing circuit is provided, and the common graphic dividing circuit can alternately perform division of a drawing pattern and division of a shot size pattern of the drawing pattern, and create an energy map in the former case. 6. The charged particle beam drawing apparatus according to claim 5, wherein pattern drawing is performed in the latter case. 8. When the size of the shot size pattern is larger than the section size of the energy map, the shot time is corrected based on the stored energy value of the center section of the plurality of sections related to the shot size pattern. 6. The charged particle beam drawing apparatus according to claim 5, wherein: 9. The method according to claim 1, wherein when the size of the shot size pattern is larger than the section size of the energy map, the shot time is corrected based on an average value of stored energy values of a plurality of sections related to the shot size pattern. Item 6. A charged particle beam drawing apparatus according to Item 5.