JP2013045876A - Shot data creation method, charged particle beam lithography and charged particle beam lithography method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for creating shot data in a format which facilitates checking of data which do not change between instances of the same pattern layout.SOLUTION: The shot data creation method involves creating shot data necessary to draw a pattern at a desired position by means of three-step deflection. The shot data comprises: a first data region containing coordinate data deflected by a first deflector; a second data region containing coordinate data deflected by a second deflector; and a third data region containing coordinate data deflected by a third deflector, which are all defined by a plurality of words, each composed of a prescribed number of bits. In all of the first to the third regions, the shot data is created in a format which is discriminated between the words defining invariable data which does not change when layouts are the same and the words defining variable data which changes even when layouts are the same.

Description

  The present invention relates to a method for creating shot data, a charged particle beam drawing apparatus, and a charged particle beam drawing method, and for example, relates to a method for creating shot data generated in a drawing apparatus.

  Lithography technology, which is responsible for the progress of miniaturization of semiconductor devices, is an extremely important process for generating a pattern among semiconductor manufacturing processes. In recent years, with the high integration of LSI, circuit line widths required for semiconductor devices have been reduced year by year. In order to form a desired circuit pattern on these semiconductor devices, a highly accurate original pattern (also referred to as a reticle or a mask) is required. Here, the electron beam (electron beam) drawing technique has an essentially excellent resolution, and is used for producing a high-precision original pattern.

FIG. 8 is a conceptual diagram for explaining the operation of the variable shaping type electron beam drawing apparatus.
The variable shaped electron beam (EB) drawing apparatus operates as follows. In the first aperture 410, a rectangular opening for forming the electron beam 330, for example, a rectangular opening 411 is formed. Further, the second aperture 420 is formed with a variable shaping opening 421 for shaping the electron beam 330 having passed through the opening 411 of the first aperture 410 into a desired rectangular shape. The electron beam 330 irradiated from the charged particle source 430 and passed through the opening 411 of the first aperture 410 is deflected by the deflector, passes through a part of the variable shaping opening 421 of the second aperture 420, and passes through a predetermined range. The sample 340 mounted on a stage that continuously moves in one direction (for example, the X direction) is irradiated. That is, the drawing area of the sample 340 mounted on the stage in which the rectangular shape that can pass through both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is continuously moved in the X direction. Drawn on. A method of creating an arbitrary shape by passing through both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is called a variable shaping method (VSB method) (for example, refer to Patent Document 1).

  With the recent miniaturization of patterns, the amount of pattern data is increasing. In the drawing apparatus, input drawing data (layout data) is converted into data to generate shot data for each shot of the beam. As the number of patterns increases, the number of shots increases accordingly, and the amount of shot data increases. The generated shot data is transferred to each device in the drawing apparatus. For this reason, when the amount of data increases, there is a problem that the transfer time for transferring shot data increases, and as a result, the throughput of the drawing apparatus decreases. Therefore, reduction of the data amount is desired. The shot data is composed of a plurality of data areas, and each data area is composed of, for example, 4 words. It is desirable to check whether the shot data to be transferred is correct data. Conventionally, when transferring, for example, using the checksum function, the sum of the words in the same order in each data area is calculated to check whether the transfer data matches between the transfer source and the transfer destination. It was.

  Here, data such as irradiation time, pattern position information, or arbitrary parameters are mixed in the word for which the sum is calculated. The positional information of the pattern of each shot is invariant data that does not vary if the same pattern layout is used. On the other hand, arbitrary parameters, irradiation times, and the like are variable data that may vary even with the same pattern layout. For example, if variable data such as irradiation time changes, the sum calculated by the checksum function changes. Therefore, when it is desired to check only the pattern position information using data of the same pattern layout, it is not possible to check using the sum. For this reason, there has been a problem that it is not easy to check pattern position information.

JP 2008-182073 A

  Here, as described above, there is a problem that the amount of shot data increases. In addition, there is a problem that it is not easy to check data that does not change, such as pattern position information.

  FIG. 9 is a diagram illustrating an example of a shot data format. Note that the format of the shot data shown in FIG. 9 is not known. FIG. 9 shows an example of shot data when the beam of each shot is irradiated to a desired position on the sample by two-stage deflection of the main and sub stages of the shaped beam. In the two-stage deflection of the main and sub stages, the sample is virtually divided into mesh-like regions called subfields (SF), and the shaped beam is deflected to the reference position of the SF to be drawn by the main deflector. A deflector deflects the shaped beam by a relative distance from the reference position of the SF to a predetermined position in the SF. In the format shown in FIG. 9, a data area A ′ in which data for specifying an SF is defined and a data area B ′ in which data for specifying each shot in the SF are defined are shown. Each data area is composed of 4 words of 32 bits (4 bytes) per word, and each has a data amount of 16 bytes. In FIG. 9, arbitrary parameters including a main deflection data header (MH) and an SF counter are defined in the first word of the data area A ′. In the second word, the X coordinate of SF is defined. In the third word, the Y coordinate of SF is defined. An optional parameter is defined in the fourth word. In the first word of the data area B ', a sub-deflection data header (SH), a C-code indicating an SF end flag, and the X coordinate of the shot position are defined. In the second word, the graphic code (k-code) of the shot graphic and the Y coordinate of the shot position are defined. In the third word, the figure size (L1, L2) of the shot figure is defined. The irradiation time is defined in the fourth word. In such a format, the data amount of 16 bytes increases as the number of shots in the SF increases by one. In general, several hundred shaped beams are shot in one SF. It is expected to increase further in the future. For this reason, the amount of shot data increases more and more. Therefore, there is a problem that the data transfer time further increases. In addition, the first parameter of the data area A ′ includes an arbitrary parameter that becomes variable data whose contents may fluctuate even in the same pattern layout. The first pattern of the data area B ′ has the same pattern layout. The X coordinate of the shot position, which is invariant data that does not fluctuate between them, is defined. Therefore, the sum of the first words is not necessarily the same value even in the same pattern layout, and it is possible to check the pattern position information with such sum between shot data of the same pattern layout. Can not. Therefore, there is a problem that it is not easy to check data that does not change, such as pattern position information.

  In view of the above, an object of one embodiment of the present invention is to provide a method and apparatus that can create shot data in a format that can easily check data that does not vary between the same pattern layouts, such as pattern position information. Another object of the present invention is to further reduce the amount of shot data.

A method for creating shot data according to an aspect of the present invention includes:
A method of creating shot data for drawing a pattern at a desired position by deflecting a charged particle beam for a shot by three stages so that a desired position on a sample is irradiated using a three-stage deflector. ,
The shot data includes first to third data areas defined by 3 words each having a predetermined number of bits,
An arbitrary parameter is deflected to the first word in the first data area, one of the two-dimensional coordinate data indicated by the first deflector deflected to the second word, and the first deflector deflected to the third word. The other two-dimensional coordinate data is defined respectively.
An arbitrary parameter is deflected to the first word of the second data area, one of the two-dimensional coordinate data that the second deflector deflects to the second word, and the second deflector deflects to the third word The other of the coordinate data shown in two dimensions is defined in one of the second word and the third word, and a graphic code of the charged particle beam to be shot is defined respectively.
The coordinate data shown in two dimensions, in which the irradiation time is in the first word of the third data area and the third deflector is deflected in the second word, is the graphic size of the charged particle beam shot in the third word Are characterized in that shot data is created in a format defined respectively.

  With this configuration, data that does not change, such as pattern position information, and variable data that changes can be defined in different words. Therefore, even when variable data is changed, it is possible to check data that does not change, such as pattern position information.

Further, when creating shot data, a fourth data area defined by three words composed of a predetermined number of bits is created together with the first to third data areas,
The total number obtained by adding all the words of the first word data in the first to third data areas to the first word of the fourth data area is defined as a value for error detection of the first word data. The total number of all the second word data words in the first to third data areas added to the second word is defined as a value for error detection of the second word data. It is preferable that the total number of all the third word data words in the first to third data areas is defined as a value for error detection of the third word data.

A method of creating shot data according to another aspect of the present invention is as follows.
A method of creating shot data for drawing a pattern at a desired position by deflecting a charged particle beam for a shot by three stages so that a desired position on a sample is irradiated using a three-stage deflector. ,
The shot data is deflected by a second data deflector and a first data area defined by a plurality of words each having a predetermined number of bits and including coordinate data deflected by the first deflector. A second data area containing coordinate data; and a third data area containing coordinate data deflected by a third deflector;
In each of the first to third data areas, a word in which invariant data that does not change if the same layout is defined, a word that defines variable data that may vary even in the same layout, and It is characterized in that shot data is created in a format that distinguishes between the two.

A charged particle beam drawing apparatus according to one embodiment of the present invention includes:
An emission part for emitting a charged particle beam;
First to third deflectors for deflecting the charged particle beam for each shot in three stages so as to irradiate a desired position on the sample;
First to fourth data areas each defined by 3 words each having a predetermined number of bits are provided, and an arbitrary parameter is set in the first word of the first data area, and the first deflection is set in the second word. One of the two-dimensional coordinate data deflected by the device is defined, and the other of the two-dimensional coordinate data deflected by the first deflector is defined in the third word, and the first word in the second data area An optional parameter in the eye, one of the two-dimensional coordinate data deflected by the second deflector in the second word and the other of the two-dimensional coordinate data deflected by the second deflector in the third word However, a graphic code of the charged particle beam to be shot is further defined in one of the second word and the third word, and the irradiation time is set in the second word in the first word of the third data area. Secondary that the third deflector deflects to the eye And coordinate data, the shot data generation unit figure size of the charged particle beam to be shot to the third word is, to generate the shot data in each defined format indicated by,
A transfer unit for transferring shot data;
An input unit for inputting the transferred shot data;
A deflection amount calculator for calculating a deflection amount to be deflected by the first to third deflectors using the input shot data;
It is provided with.

The charged particle beam drawing method of one embodiment of the present invention includes:
First to fourth data areas each defined by 3 words each having a predetermined number of bits are provided, and an arbitrary parameter is set in the first word of the first data area, and the first deflection is set in the second word. One of the two-dimensional coordinate data deflected by the device is defined, and the other of the two-dimensional coordinate data deflected by the first deflector is defined in the third word, and the first word in the second data area An optional parameter in the eye, one of the two-dimensional coordinate data deflected by the second deflector in the second word and the other of the two-dimensional coordinate data deflected by the second deflector in the third word However, a graphic code of the charged particle beam to be shot is further defined in one of the second word and the third word, and the irradiation time is set in the second word in the first word of the third data area. Secondary that the third deflector deflects to the eye A step coordinate data, graphic size of the charged particle beam to be shot to the third word is, to generate the shot data in each defined format indicated by,
Transferring the generated shot data; and
Inputting the transferred shot data; and
Calculating a deflection amount to be deflected by the first to third deflectors using the input shot data;
Using the first to third deflectors to deflect the charged particle beam for each shot in three stages so as to irradiate a desired position on the sample with the calculated deflection amount; and
It is provided with.

  According to one aspect of the present invention, it is possible to create shot data in a format that can easily check data that does not vary, such as pattern position information. Further, according to another embodiment of the present invention, the amount of shot data can be further reduced.

1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to Embodiment 1. FIG. FIG. 3 is a conceptual diagram for explaining beam shaping in the first embodiment. FIG. 3 is a conceptual diagram for explaining each region in the first embodiment. 6 is a diagram illustrating an example of a format of shot data in Embodiment 1. FIG. 6 is a conceptual diagram for explaining an example of a deflection time in Embodiment 1. FIG. It is a conceptual diagram of the comparative example for demonstrating the deflection | deviation time at the time of defining each figure code for each shot. 6 is a conceptual diagram for explaining a deflection time when only one graphic code is defined in one under-subfield data in Embodiment 1. FIG. It is a conceptual diagram for demonstrating operation | movement of a variable shaping type | mold electron beam drawing apparatus. It is a figure which shows an example of a shot data format.

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

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to the first embodiment. In FIG. 1, the drawing apparatus 100 includes a drawing unit 150 and a control unit 160. The drawing apparatus 100 is an example of a charged particle beam drawing apparatus. In particular, it is an example of a variable shaping type drawing apparatus. The drawing unit 150 includes an electron column 102 and a drawing chamber 103. In the electron column 102, there are an electron gun 201, an illumination lens 202, a blanker 212, a blanking aperture 214, a first shaping aperture 203, a projection lens 204, a first shaping deflector 220, and a second shaping deflector 222. The second shaping aperture 206, the objective lens 207, the first objective deflector 232, the second objective deflector 230, and the third objective deflector 234 are disposed. An XY stage 105 is disposed in the drawing chamber 103. On the XY stage 105, a sample 101 such as a mask to be a drawing target substrate at the time of drawing is arranged. The sample 101 includes an exposure mask for manufacturing a semiconductor device. Further, the sample 101 includes mask blanks to which a resist is applied and nothing is drawn yet.

  The control unit 160 includes a control computer unit 110, a deflection control circuit unit 120, digital / analog conversion (DAC) units 130, 132, 134, 136, 137, 138, and a storage device 140 such as a magnetic disk device. . The control computer unit 110, the deflection control circuit unit 120, and the storage device 140 such as a magnetic disk device are connected to each other via a bus (not shown).

  In the control computer unit 110, a shot data generation unit 112, storage devices 114 and 118 such as a memory, and a transfer processing unit 116 are arranged. Each function such as the shot data generation unit 112 and the transfer processing unit 116 may be configured by hardware such as an electric circuit, or may be configured by software such as a program that executes these functions. Alternatively, it may be configured by a combination of hardware and software. Information input / output to / from the shot data generation unit 112 and the transfer processing unit 116 and information being calculated are stored in the storage device 118 each time.

  In the deflection control circuit unit 120, an input unit 122, storage devices 124 and 129 such as a memory, a checksum processing unit 126, and a deflection amount calculation unit 128 are arranged. Each function such as the input unit 122, the checksum processing unit 126, and the deflection amount calculation unit 128 may be configured by hardware such as an electric circuit, or may be configured by software such as a program that executes these functions. Good. Alternatively, it may be configured by a combination of hardware and software. Information input / output to / from the input unit 122, checksum processing unit 126, and deflection amount calculation unit 128 and information being calculated are stored in the storage device 129 each time.

  The DAC unit 130 receives a blanking signal as a digital signal from the deflection control circuit unit 120, converts it into an analog signal, amplifies it, and applies an output voltage as a deflection voltage to the blanker 212.

  The DAC unit 132 receives the first shaping deflection signal (graphic type signal), which is a digital signal, from the deflection control circuit unit 120, converts it into an analog signal, amplifies it, and outputs the output voltage as the deflection voltage to the first shaping signal. Applied to the deflector 220.

  The DAC unit 134 receives the second shaping deflection signal (size signal) which is a digital signal from the deflection control circuit unit 120, converts it into an analog signal, amplifies it, and outputs the output voltage as the deflection voltage to the second shaping deflection signal. Applied to the device 222.

  The DAC unit 136 receives the sub-deflection data signal that is a digital signal from the deflection control circuit unit 120, converts it into an analog signal, amplifies it, and applies the output voltage as a deflection voltage to the second objective deflector 230.

  The DAC unit 137 receives the main deflection data signal, which is a digital signal, from the deflection control circuit unit 120, converts it to an analog signal, amplifies it, and applies the output voltage as a deflection voltage to the first objective deflector 232.

  The DAC unit 138 receives the third deflection data signal, which is a digital signal, from the deflection control circuit unit 120, converts it into an analog signal, amplifies it, and applies an output voltage as a deflection voltage to the third objective deflector 234. To do.

  Here, FIG. 1 shows a configuration necessary for explaining the first embodiment. The drawing apparatus 100 may normally have other necessary configurations. In the example of FIG. 1, the beam is irradiated to a desired position on the sample 101 by performing three-stage deflection using a three-stage objective deflector.

  The storage device 140 (storage unit) stores drawing data (layout data) composed of a plurality of graphic patterns from the outside.

  When the electron beam 200 emitted from the electron gun 201 (emission unit) passes through the blanker 212 (blanking deflector), it is controlled by the blanker 212 so as to pass through the blanking aperture 214 in the beam-on state. In the beam OFF state, the entire beam is deflected so as to be shielded by the blanking aperture 214. The electron beam 200 that has passed through the blanking aperture 214 until the beam is turned off after the beam is turned off becomes one shot of the electron beam. The blanker 212 controls the direction of the passing electron beam 200 to alternately generate a beam ON state and a beam OFF state. For example, a voltage may be applied to the blanker 212 when the beam is OFF, without applying a voltage when the beam is ON. The irradiation amount per shot of the electron beam 200 irradiated on the sample 101 is adjusted in the irradiation time of each shot.

  As described above, the electron beam 200 of each shot generated by passing through the blanker 212 and the blanking aperture 214 illuminates the entire first shaping aperture 203 having a rectangular shape, for example, a rectangular hole, by the illumination lens 202. Here, the electron beam 200 is first formed into a rectangle, for example, a rectangle. Then, the electron beam 200 of the first aperture image that has passed through the first shaping aperture 203 is projected onto the second shaping aperture 206 by the projection lens 204. At that time, the first shaping deflector 220 and the second shaping deflector 222 control the deflection of the first aperture image on the second shaping aperture 206 and change the beam shape and dimensions (variable). Molding). Such variable forming is performed for each shot. Such variable shaping is generally shaped into different beam shapes and dimensions for each shot. In the first embodiment, as will be described later, between shots in which shot data is generated for the same third deflection region (TF), each shot is formed into the same figure type, and the size is set for each shot. May be different. Then, the electron beam 200 of the second aperture image that has passed through the second shaping aperture 206 is focused by the objective lens 207, and the first objective deflector 232, the second objective deflector 230, and the third Three-stage deflection is performed by the objective deflector 234 and the desired position of the sample 101 placed on the XY stage 105 that moves continuously is irradiated.

  FIG. 2 is a conceptual diagram for explaining beam shaping in the first embodiment. The first shaping aperture 203 is formed with a rectangular, for example, rectangular or square opening 32 for shaping the electron beam 200. Further, the second shaping aperture 206 is formed with a variable shaping opening 34 for shaping the electron beam 200 that has passed through the opening 32 of the first shaping aperture 203 into a desired rectangular shape. The variable shaped opening 34 is formed by combining a side parallel and orthogonal to the side of the opening 32 and a side rotated n times (n is 1 to 4) 45 degrees with respect to the side of the opening 32. The In other words, the variable shaped opening 34 has a shape in which one side of the hexagon is deleted and opened, one side of the rectangle is deleted and opened, and the deleted side portions are connected to each other. The electron beam 200 irradiated from the electron gun 201 and passed through the opening 32 of the first shaping aperture 203 is deflected by the first shaping deflector 220 and the second shaping deflector 222, and the second shaping aperture 206 The sample 101 mounted on the XY stage 105 that passes through a part of the variable shaping opening 34 and continuously moves in a predetermined direction (for example, the X direction) is irradiated. That is, the sample 101 mounted on the XY stage 105 that has a shape that can pass through both the opening 32 of the first shaping aperture 203 and the variable shaping opening 34 of the second shaping aperture 206 continuously moves in the X direction. It is drawn in the drawing area. In the example of FIG. 2, the rectangular shape is first formed by passing through the opening 32 of the first shaping aperture 203. Next, the shaped beam shaped at the opening 32 is deflected so as to straddle the 135 degree side of the variable shaped opening 34 of the second shaping aperture 206, for example. As a result, a part of the beam surrounded by the two sides including one corner of the rectangle formed by the opening 32 and the 135-degree side of the variable shaping opening 34 is not blocked by the second shaping aperture 206 and is variable shaped. Pass through opening 34. As a result, the electron beam 200 is variably shaped into a right isosceles triangle, and the sample 101 is irradiated with a shot beam 36 having a right isosceles triangle.

  FIG. 3 is a conceptual diagram for explaining each region in the first embodiment. In FIG. 3, the drawing area 10 of the sample 101 is virtually divided into a plurality of stripe areas 20 (first small areas) in a strip shape in the y direction, for example, with a deflectable width of the first objective deflector 232. The Each stripe region 20 is virtually divided into a plurality of subfields (SF) 30 (second small regions) in a mesh shape with a deflectable size of the second objective deflector 230. Each SF 30 is virtually divided into a third field (TF: Tertiary Field) 40 (third small area) which is a plurality of under subfields in a mesh shape with a deflectable size of the third objective deflector 234. The Then, shot figures 52, 54, and 56 are drawn at each shot position in each TF 40. The number of TF divisions in each SF is preferably 10 or less in the vertical and horizontal directions, for example. More preferably, 5 or less in length and width are desirable.

  When drawing the shaped electron beam 200 on the sample 101, first, the shaped electron beam 200 is deflected to the reference position of the SF 30 where the first objective deflector 232 is shot. For example, the center position of the SF 30 is suitable as the reference position of the SF 30. Alternatively, other positions may be used as the reference position. Since the XY stage 105 is moving, the first objective deflector 232 deflects the electron beam 200 so as to follow the movement of the XY stage 105. Then, the second objective deflector 230 deflects the electron beam 200 shaped from the reference position of the SF 30 to the reference position of the TF 40 shot in the SF 30. As a reference position of TF40, for example, the center position of TF40 is suitable. Alternatively, other positions may be used as the reference position. Then, each position in the TF 40 is irradiated by the third objective deflector 234. In the first embodiment, three-stage deflection is performed as described above. In order to perform the drawing operation as described above, first, shot data is generated.

  As the shot data generation process, the shot data generation unit 112 deflects the electron beam for shots by three stages so that the desired position on the sample 101 is irradiated using the above-described three-stage deflector. Shot data for drawing a pattern is generated. Specifically, the shot data generation unit 112 reads drawing data from the storage device 140, performs a plurality of stages of data conversion processing, and generates apparatus-specific shot data. In order to draw a graphic pattern by the drawing apparatus 100, it is necessary to divide each graphic pattern defined in the drawing data into a size that can be irradiated with one beam shot. Therefore, the shot data generation unit 112 generates shot figures by dividing each figure pattern into a size that can be irradiated with a single shot of a beam in order to actually draw. Then, data for shots is generated for each shot figure. In the first embodiment, shot data is generated in the following format in order to reduce an increase in the amount of shot data due to an increase in the number of shots.

  FIG. 4 is a diagram showing an example of a format of shot data in the first embodiment. FIG. 4 shows an example of shot data for a shot beam irradiated in one TF 40 in one SF 30. Shot data includes a data area A (first data area), a data area B (second data area), and a data area C (third data area) defined by three words each having a predetermined number of bits. ) And a data area D (fourth data area). Here, each word consists of 32 bits. When 8 bits are 1 byte, the data amount is 4 bytes per word. Therefore, each data area is configured with a data amount of 12 bytes.

  A main deflection data header (MH) and optional parameters are defined in the first word of the data area A. In the second word of the data area A, one of the coordinate data of the SF 30 shown in two dimensions that is deflected by the first objective deflector 232 is defined. In the third word of the data area A, the other of the coordinate data of the SF 30 shown in two dimensions that is deflected by the first objective deflector 232 is defined. Thus, the data area A includes coordinate data deflected by the first objective deflector 232. In the example of FIG. 4, the X coordinate of the SF 30 is defined in the second word, and the Y coordinate of the SF 30 is defined in the third word. Note that the (X, Y) coordinates of the SF 30 are invariant data that does not vary between the same pattern layouts. On the other hand, the optional parameter of the first word is variable data that may vary between the same pattern layouts.

  A sub deflection data header (SH) and optional parameters are defined in the first word of the data area B. C-code such as SF end flag in the second word of data area B, K-code which is a figure code of the electron beam to be shot, and coordinates of TF 40 which is shown in two dimensions by the second objective deflector 230 to be deflected One of the data is defined. In the third word of the data area B, the other of the TD information indicating the data information of the TF 40 and the coordinate data indicated by the TF 40 in two dimensions deflected by the second objective deflector 230 is defined. Thus, the data area B includes coordinate data deflected by the second objective deflector 230. In the example of FIG. 4, C-code and K-code are defined in the second word of the data area B, and TD information is defined in the third word of the data area B. However, the present invention is not limited to this. The C-code, K-code, and TD information may be defined in the second word or the third word of the data area B, respectively. In the example of FIG. 4, the X coordinate of the TF 40 is defined in the second word, and the Y coordinate of the TF 40 is defined in the third word. The (X, Y) coordinates of the TF 40 are invariant data that does not vary between the same pattern layouts. Further, the C-code, K-code, and TD information are all invariant data that does not vary between the same pattern layouts. On the other hand, the optional parameter of the first word is variable data that may vary between the same pattern layouts.

  In the first word of the data area C, the third deflection data header (TH), the settling time of the DAC unit 138 for the third objective deflector 234, and the shot beam irradiation time are defined. Coordinate data indicating the (X, Y) coordinates of the irradiation position (shot position) in the two-dimensional TF 40 that is deflected by the third objective deflector 234 is defined in the second word of the data area C. In the third word of the data area C, the TC-code that is the first and last flags of the shot into the TF 40 and the figure size (L1, L2) of the shot electron beam are defined. Thus, the data area C includes coordinate data deflected by the third objective deflector 234. The (X, Y) coordinates of the shot position and the figure size (L1, L2) of the shot electron beam are invariant data that does not vary between the same pattern layouts. The TC-code is also invariant data that does not vary between the same pattern layouts. On the other hand, the settling time and irradiation time of the first word are variable data that may vary between the same pattern layouts. Since a plurality of electron beams are shot in one TF 40, the data for each shot beam irradiated in the TF 40 is defined in order in the same format as the data area C. Then, after the data for all shots in the TF 40 continues, the next data area D is defined at the end for the TF 40.

  A checksum 1 (a checksum value of the first word) indicating the total number of all the data words of the first words of the data areas A to C added to the first word of the data area D is the first word. Defined as a value for data error detection. A checksum 2 (checksum value of the second word) indicating the total number of all the data words of the second words of the data areas A to C added to the second word of the data area D is the second word. Defined as a value for data error detection. A checksum 3 (a checksum value of the third word) indicating the total number of all the third word data of the data areas A to C added to the third word of the data area D is the third word. Defined as a value for data error detection. Subsequently, the data for the next TF 40 in the SF 30 is defined in the format of the data areas B to D. Then, after all the data for the TF 40 in the SF 30 is defined, the next data for the SF 30 is defined in the format of the data areas A to D. Similarly, data for the SF 30 in each stripe region 20 is defined in order.

  In the first embodiment, shot data is created in the above format. In such a format, each data area A to D is composed of 3 words of 32 bits (4 bytes) per word, and each has a data amount of 12 bytes. Therefore, the data amount of each data area can be reduced compared to the format shown in FIG. Even when shot data is generated in the format of FIG. 9, the SF size needs to be reduced with the recent increase in the number of shots. If the SF size of the format of FIG. 9 and the TF size of FIG. 4 are divided into the same size, for example, if the number of shots per TF 40 is 3 shots or more, shot data is compared with the format shown in FIG. The total amount of data can be reduced. Usually, since there are several hundred shots per SF, even when the TF size of FIG. 4 is smaller than the SF size of the format of FIG. 9, the data amount of the entire shot data can be greatly reduced. In the first embodiment, the checksum value indicated by the data area D is defined when shot data is generated. Conventionally, the checksum value is not defined at the time of shot data generation. However, if it is defined at the time of shot data generation, if the SF size of the format of FIG. 9 and the TF size of FIG. If the number of shots is 2 shots or more, the data amount of the entire shot data can be reduced as compared with the format shown in FIG. As described above, since the data amount of the entire shot data can be greatly reduced, the transfer time of shot data after generation can be greatly reduced.

  Furthermore, in the format shown in FIG. 4, in any of the data areas A to C, variable data is aggregated in the first word, and invariant data is aggregated in the second and third words. Thus, in the data areas A to C, a word in which invariant data is defined that does not vary if the same pattern layout is used, and a word in which variable data that may vary even in the same layout are defined. Shot data is created in a format that distinguishes between Therefore, the checksum values of the second and third words can be kept the same after the shot data is generated. Therefore, after the shot data is generated, the contents of the shot data can be checked if the same pattern layout is used. For example, by arranging only the position data in a specific area, it is possible to check the pattern position information even if there is a variation in irradiation time or the like. In the example of FIG. 4, variable data is aggregated in the first word, but the present invention is not limited to this. A format in which variable data is aggregated in the second or third word may be used. Furthermore, variable data and invariant data need not be mixed in the same word. In one of the data areas A to C, for example, variable data is aggregated in the nth word, and in other data areas, The variable data may be aggregated in words other than the nth word. In such a case, when calculating the checksum value, the sum may be calculated between words in which variable data is defined, and the sum may be calculated between words in which invariant data is defined.

  As described above, according to the first embodiment, it is possible to create shot data in a format that can easily check data that does not vary, such as pattern position information. Furthermore, the amount of shot data can be reduced.

  Next, the generated shot data is stored (stored) in a storage device 114 such as a memory. Then, the transfer processing unit 116 reads the shot data from the storage device 114, and first calculates the total number of all the words of the first word data in the data areas A to C in the shot data. Similarly, the total number of all the data words of the second words in the data areas A to C is calculated. Similarly, the total number obtained by adding all the third data words in the data areas A to C is calculated. Then, the transfer processing unit 116 checks whether or not the calculated total number of the first word in the data areas A to C matches the value of the checksum 1 defined in the first word of the data area D. Similarly, the transfer processing unit 116 checks whether or not the calculated total number of the second word in the data areas A to C matches the value of the checksum 2 defined in the second word of the data area D. . Similarly, it is checked whether the calculated total number of the third word in the data areas A to C matches the value of the checksum 3 defined in the third word of the data area D. With this processing operation, it is possible to verify whether or not there is an error in the shot data stored in the storage device 114. As a result of the verification, shot data having no error is transferred to the deflection control circuit unit 120. As described above, since the checksum value is defined when the shot data is generated, it is possible to verify whether or not there is an error in the shot data stored in the storage device 114 before the transfer, and also verify whether there is an error in the shot data at the time of transfer. it can. Further, as described above, since the data amount of the entire shot data is reduced as compared with the format shown in FIG. 9, the storage speed and the transfer speed can be increased. If there is an error as a result of the verification, the transfer may be stopped and the result may be output to a monitor (not shown).

  In the deflection control circuit unit 120, the input unit 122 inputs the transferred shot data. Then, the input unit 122 calculates the total number obtained by adding all the words of the first word data in the data areas A to C in the input shot data. Similarly, the total number of all the data words of the second words in the data areas A to C is calculated. Similarly, the total number obtained by adding all the third data words in the data areas A to C is calculated. Then, the input unit 122 checks whether the calculated total number of the first word in the data areas A to C matches the value of the checksum 1 defined in the first word of the data area D. Similarly, the input unit 122 checks whether the calculated total number of the second word in the data areas A to C matches the value of the checksum 2 defined in the second word of the data area D. Similarly, the input unit 122 checks whether the calculated total number of the third word in the data areas A to C matches the value of the checksum 3 defined in the third word of the data area D. With this processing operation, it is possible to verify whether or not there is an error in the transferred shot data. As a result of the verification, shot data having no error is stored (stored) in the storage device 124. As described above, it is possible to verify whether or not there is an error in the transferred shot data. If there is an error as a result of the verification, the subsequent processing is temporarily stopped and the result may be output to a monitor (not shown).

  Next, the checksum processing unit 126 reads the shot data from the storage device 124, and first calculates the total number obtained by adding all the words of the first word data in the data areas A to C in the shot data. Similarly, the total number of all the data words of the second words in the data areas A to C is calculated. Similarly, the total number obtained by adding all the third data words in the data areas A to C is calculated. Then, the checksum processing unit 126 checks whether the calculated total number of the first word in the data areas A to C matches the value of the checksum 1 defined in the first word of the data area D. . Similarly, the checksum processing unit 126 checks whether the calculated total number of the second word in the data areas A to C matches the value of the checksum 2 defined in the second word of the data area D. To do. Similarly, the checksum processing unit 126 checks whether the calculated total number of the third word in the data areas A to C matches the value of the checksum 3 defined in the third word of the data area D. To do. With this processing operation, it is possible to verify whether or not the shot data stored in the storage device 124 has an error. Then, as a result of verification, shot data having no error is transmitted (output) to the deflection amount calculation unit 128. With the above processing, it is possible to verify whether or not there is an error in the shot data stored in the storage device 124, and it is possible to verify whether or not there is an error in the shot data immediately before the deflection amount calculation. In addition, as described above, since the data amount of the entire shot data is reduced as compared with the format shown in FIG. 9, the storage speed and the transmission speed can be increased. If there is an error as a result of the verification, the transfer may be stopped and the result may be output to a monitor (not shown).

  Next, the deflection amount calculation unit 128 uses the input shot data to determine the deflection amounts to be deflected by the first objective deflector 232, the second objective deflector 230, and the third objective deflector 234, respectively. Calculate. Similarly, the deflection amount calculation unit 128 generates a timing signal for causing the blanker 212 to have a predetermined irradiation time using the input shot data. Similarly, the deflection amount calculation unit 128 calculates the deflection amounts deflected by the first shaping deflector 220 and the second shaping deflector 222 using the input shot data.

  The timing signal for the blanker 212 is output to the DAC unit 130. A digital signal indicating the deflection amount for the first shaping deflector 220 is output to the DAC unit 132. A digital signal indicating the deflection amount for the second shaping deflector 222 is output to the DAC unit 134. A digital signal indicating the deflection amount for the second objective deflector 230 is output to the DAC unit 136. A digital signal indicating the deflection amount for the first objective deflector 232 is output to the DAC unit 137. A digital signal indicating the deflection amount for the third objective deflector 234 is output to the DAC unit 138. Then, the drawing unit 150 uses the first objective deflector 232, the second objective deflector 230, and the third objective deflector 234 to each position on the sample 101 with the calculated deflection amount. The electron beam for each shot is deflected in three stages so as to be irradiated.

  Here, in the shot data format shown in FIG. 4, a graphic code (K-code) is defined in the data area B defining the position data of the TF 40, and the position data and size of each shot in the TF 40 are defined. It is not defined in data area C. In other words, the shot beam in the data for one TF 40 is formed into the same figure type.

  FIG. 5 is a conceptual diagram for explaining an example of the deflection time in the first embodiment. FIG. 5A illustrates the time required for deflection during beam shaping. The deflection amount to be deflected by the first shaping deflector 220 is determined by the graphic code in the data area B. For example, time t2 is required to move (deflect) the beam from a position where the beam is shaped into a rectangle such as a square or a rectangle to a position where the beam is shaped into a right isosceles triangle. On the other hand, the deflection amount to be deflected by the second shaping deflector 222 is determined by the figure size (L1, L2) of the data area C. For example, time t1 is required to move (deflect) the beam so as to change only the dimensions within a rectangle such as the same square or rectangle. Similarly, time t1 is required to move (deflect) the beam so as to change only the dimensions within the same right isosceles triangle. The larger the deflection amount, the longer the settling time required for the corresponding DAC unit. Therefore, as is clear from FIG. 5A, the time t2 in which the amount of movement (deflection) is large is longer than the time t1. As described above, in the example of FIG. 1, the graphic shape is determined by the first shaping deflector 220 and the graphic size is determined by the second shaping deflector 222.

  FIG. 5B illustrates a time for moving (deflecting) the beam by the second objective deflector 230 from one TF 40 to the next TF 40. If movement (deflection) between shot positions in the same TF 40 takes time t1 '(not shown), it takes time t2' to move (deflection) the beam from one TF 40-1 to the next TF 40-2. As described above, the larger the deflection amount, the longer the settling time required for the corresponding DAC unit. Therefore, as is clear from FIG. 5B, the time t2 'having the larger movement (deflection) amount is longer than the time t1'.

  Here, for beam shaping and objective deflection, when the DAC units of the deflectors with a small deflection amount are set to the same resolution, the time t1 and the time t1 'can be made the same. Similarly, when the DAC units of the deflectors having a large deflection amount are set to the same resolution, the time t2 and the time t2 'can be set to the same level.

  Hereinafter, when a graphic code is defined for each shot as in the shot data format shown in FIG. 9, and in one TF 40 data as in the shot data format of the first embodiment shown in FIG. The difference in deflection speed between the case where only one graphic code is defined will be described.

  FIG. 6 is a conceptual diagram for explaining a deflection time when a graphic code is defined for each shot. A case where a triangular pattern 50 is drawn in one TF 40 as shown in FIG. Here, a case is shown in which the triangular pattern 50 is shot and divided into three rectangular and three triangular shot figures. In FIG. 6A, the shot order of shot figures is indicated by numbers. Usually, the shot order is repeated by drawing each shot figure in the x direction and then proceeding one step in the y direction, and similarly drawing each shot figure in the x direction. Therefore, when a graphic code is defined for each shot shown in FIG. 6A, the shot operation proceeds in the order of rectangle, rectangle, triangle, rectangle, triangle, and triangle as shown in FIG. 6B. In this case, it takes t1 to move from the first rectangle to the second rectangle. The time required to move from the second rectangle to the third triangle takes t2 because the figure type is different. The time required to move from the third triangle to the fourth rectangle is t2 because the figure type is different. The time required to move from the fourth rectangle to the fifth triangle is t2 because the figure type is different. It takes time t1 to move from the fifth triangle to the sixth triangle. Therefore, when the triangular pattern 50 is drawn, time is required for t2 three times and t1 once.

  FIG. 7 is a conceptual diagram for explaining the deflection time when only one graphic code is defined in one TF data in the first embodiment. As shown in FIG. 7A, when the triangular pattern 50 is drawn in one TF 40, the shot is divided into three rectangular and three triangular shot figures, as in FIG. 6A. In the first embodiment, since only one graphic code is defined in one TF40 data, when the shot is divided into two types of graphics, the TF40 data is divided by the number of graphic types. In the example of FIG. 7A, since there are two types of graphics, a rectangle and a triangle, the data is divided into TF 40-1 and TF 40-2 and generated. In TF40-1, data when three triangles 51 are shot is generated, and in TF40-2, data when three rectangles 53 are shot is generated. When drawing such TF40-1 and TF40-2 in order, it takes the following time. As shown in FIG. 7B, after drawing TF40-1 as a triangle, a triangle, and a triangle, it moves to TF40-2, and the shot operation proceeds in the order of rectangle, rectangle, and rectangle. In this case, it takes t1 to move from the first triangle to the second triangle. Similarly, it takes t1 to move from the second triangle to the third triangle. After that, TF movement takes t2 '. Then, it takes time t1 to move from the fourth rectangle to the fifth rectangle. Similarly, it takes t1 to move from the fifth rectangle to the sixth rectangle. If t2 '= t2, when the triangular pattern 50 is drawn, it takes time t1 once and t1 four times. Therefore, when only one graphic code is defined in one TF data in the first embodiment, the deflection time can be shortened compared to the case where a graphic code is defined for each shot. As described above, by generating shot data in the format shown in FIG. 4, it is possible to further improve the drawing throughput by utilizing the characteristics of the DAC unit for deflection (deflection amplifier).

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

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

  In addition, all shot data formats, shot data creation methods, charged particle beam drawing apparatuses and methods that include elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

10 Drawing area 20 Stripe area 30 SF
32 Aperture 34 Variable shaping aperture 36 Shot beam 40 TF
50 Triangular pattern 52, 54, 56 Shot figure 53 Rectangle 100 Drawing device 101, 340 Sample 102 Electronic column 103 Drawing chamber 105 XY stage 110 Control computer unit 112 Shot data generation unit 114, 118 Storage device 116 Transfer processing unit 120 Deflection control Circuit unit 122 Input unit 124, 129 Storage device 126 Checksum processing unit 128 Deflection amount calculation unit 130, 132, 134, 136, 137, 138 DAC unit 140 Storage device 150 Drawing unit 160 Control unit 200 Electron beam 201 Electron gun 202 Illumination Lens 203 First shaping aperture 204 Projection lens 206 Second shaping aperture 207 Objective lens 212 Blanker 214 Blanking aperture 220 First shaping deflector 222 Second shaping deflector 230 Second Objective deflector 232 first objective deflector 234 the third objective deflector 330 electron beam 410 first aperture 411 opening 420 second aperture 421 variable-shaped opening 430 a charged particle source

Claims (5)

This is a shot data creation method for drawing a pattern at a desired position by deflecting a shot charged particle beam by three stages so that the desired position on the sample is irradiated using a three-stage deflector. And
The shot data includes first to third data areas defined by three words each having a predetermined number of bits,
An arbitrary parameter is deflected to the first word in the first data area, one of the two-dimensional coordinate data indicated by the first deflector deflected to the second word, and the first deflector deflected to the third word. The other two-dimensional coordinate data is defined respectively.
An arbitrary parameter is deflected to the first word of the second data area, one of the two-dimensional coordinate data that the second deflector deflects to the second word, and the second deflector deflects to the third word The other of the coordinate data shown in two dimensions is defined in one of the second word and the third word, and a graphic code of the charged particle beam to be shot is defined respectively.
The coordinate data shown in two dimensions, in which the irradiation time is in the first word of the third data area and the third deflector is deflected in the second word, is the graphic size of the charged particle beam shot in the third word Is a method of creating shot data, characterized in that shot data is created in a format defined respectively. When creating the shot data, a fourth data area defined by 3 words composed of the predetermined number of bits is created together with the first to third data areas,
The total number obtained by adding all the first word data words in the first to third data areas to the first word of the fourth data area is a value for error detection of the first word data. The total number of all the second word data words in the first to third data areas added to the second word is defined as a value for error detection of the second word data. The total number of all the third word data in the first to third data areas added to the third word is defined as a value for error detection of the third word data. The shot data creation method according to claim 1, wherein: This is a shot data creation method for drawing a pattern at a desired position by deflecting a shot charged particle beam by three stages so that the desired position on the sample is irradiated using a three-stage deflector. And
The shot data is deflected by a first data area including coordinate data deflected by a first deflector, which is defined by a plurality of words composed of a predetermined number of bits, and a second deflector. A second data area including coordinate data, and a third data area including coordinate data deflected by the third deflector,
In each of the first to third data areas, a word in which invariant data that does not change if the same layout is defined, and a word in which variable data that may vary even in the same layout are defined A method of creating shot data, characterized in that shot data is created in a format that distinguishes between and. An emission part for emitting a charged particle beam;
First to third deflectors for deflecting the charged particle beam for each shot in three stages so as to irradiate a desired position on the sample;
First to fourth data areas each defined by 3 words each having a predetermined number of bits are provided, and an arbitrary parameter is set in the first word of the first data area, and the first deflection is set in the second word. One of the two-dimensional coordinate data deflected by the device is defined, and the other of the two-dimensional coordinate data deflected by the first deflector is defined in the third word, and the first word in the second data area An optional parameter in the eye, one of the two-dimensional coordinate data deflected by the second deflector in the second word and the other of the two-dimensional coordinate data deflected by the second deflector in the third word However, a graphic code of the charged particle beam to be shot is further defined in one of the second word and the third word, and the irradiation time is defined in the first word of the third data region. The third deflector deflects in the second word Coordinate data indicating a two-dimensional, figure size of the charged particle beam to be shot to the third word is the shot data generation unit which generates a shot data in each defined format that,
A transfer unit for transferring the shot data;
An input unit for inputting the transferred shot data;
A deflection amount calculator for calculating a deflection amount to be deflected by the first to third deflectors using the input shot data;
A charged particle beam drawing apparatus comprising: First to fourth data areas each defined by 3 words each having a predetermined number of bits are provided, and an arbitrary parameter is set in the first word of the first data area, and the first deflection is set in the second word. One of the two-dimensional coordinate data deflected by the device is defined, and the other of the two-dimensional coordinate data deflected by the first deflector is defined in the third word, and the first word in the second data area An optional parameter in the eye, one of the two-dimensional coordinate data deflected by the second deflector in the second word and the other of the two-dimensional coordinate data deflected by the second deflector in the third word However, a graphic code of the charged particle beam to be shot is further defined in one of the second word and the third word, and the irradiation time is defined in the first word of the third data region. The third deflector deflects in the second word A step coordinate data indicating a two-dimensional, figure size of the charged particle beam to be shot to the third word is, to generate the shot data in each defined format that,
Transferring the generated shot data;
Inputting the transferred shot data; and
Calculating a deflection amount to be deflected by the first to third deflectors using the input shot data;
Using the first to third deflectors to deflect the charged particle beam for each shot in three stages so that a desired position on the sample is irradiated with the calculated deflection amount;
A charged particle beam drawing method comprising:

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