JPH10189436A - Apparatus and method for plotting of charged particle beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To plot one pattern without any contradiction by using a multibeam- type electron-beam plotting apparatus. SOLUTION: In a multibeam-type electron-beam plotting apparatus having a plurality of electron-beam optical systems, a logic operation is performed by using arrangement data on a chip to be formed on a wafer and by using the plotting region of every electron-beam optical system (Step S1), a plotting region which is overlapped with the chip is found (Step S2), the overlapped plotting region is regarded as one chip, plotting data on every plotting region of every electron-beam optical system is created (Step S4), the created plotting data is transferred in parallel to the corresponding electron-beam optical system (Step S5), and a plotting operation is performed simultaneously by every electron-beam optical system on the basis of the transferred plotting data (Step S6). Thereby, even when the pattern of the chip is larger than the plotting region of every charged particle-beam optical system, one chip (plotting data) corresponds surely to one charged particle-beam optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charged beam writing technique, and more particularly to a multi-beam type charged beam writing apparatus and writing method.

[0002]

2. Description of the Related Art Electron beam lithography systems have the feature of being excellent in resolution and are widely used for developing advanced devices. A feature of this electron beam writing apparatus is that an electron beam is electromagnetically and electrostatically deflected and a desired figure is drawn directly on a sample without requiring a transfer mask.

In an electron beam writing apparatus, a desired writing pattern is converted into a data format (drawing data) based on the writing apparatus configuration.
, Which is called data conversion. The drawing data is usually divided and configured in units of a beam deflection area having a size of several hundred μm to several mm. When the beam deflecting region has a main / sub two-stage deflection, the drawing data is divided for each main deflecting region, and the main deflecting region is further divided in the sub deflecting region. It is recognized as a figure arrangement.

When actually drawing a pattern on a wafer, the stage is moved to a chip position based on chip layout information indicating chip arrangement information on the wafer, and then the chip data is transferred to a drawing apparatus to draw the pattern. I do. When there are a plurality of chips, similar processing is performed to sequentially draw.

In recent years, technical development of a multi-beam type electron beam lithography system having a plurality of electron beam sources aiming at high throughput has been carried out (for example, THPChang et al.).
al.; J.vac.Sci.Technol.B8 (1990), P.1698). In this multi-beam system, since writing is performed simultaneously with a plurality of beams instead of the conventional single beam, writing throughput is expected to be significantly improved.

However, the following problems occur in the multi-beam type drawing apparatus. That is, the chip size varies depending on the type of device, and is not necessarily one.
It does not mean that one chip corresponds to one electron beam. For example, as shown in FIG. 8A, a case is considered in which 3 × 3 arrays of electron beam optical systems 81 are arranged on a wafer 80. In this case, when a pattern 83 (hatched portion in the drawing) larger than the arrangement pitch 82 of the electron beam optical system 81 is drawn, the drawing is performed using a plurality of electron beam optical systems. Similarly, drawing data corresponding to each electron beam optical system 81 is required even when the chips 85 (hatched portions in the drawing) are separated as shown in FIG. 8B.

As described above, in the writing apparatus of the multi-beam system, when the chip arrangement on the wafer does not match the arrangement of the optical system, the chip data is transferred to the drawing area of each electron beam optical system according to the chip arrangement information on the wafer. Need to be divided or reconfigured to correspond to Therefore, the stage is moved based on the chip arrangement information on the conventional wafer,
After that, in the method of transferring chip data and drawing,
It cannot cope with a multi-beam type drawing apparatus that draws simultaneously using a plurality of electron beams. That is, the data conversion method and the writing method of the conventional electron beam writing apparatus are as follows.
It could not be applied to a multi-beam type electron beam writing apparatus.

[0008]

As described above, in a conventional multi-beam type electron beam writing apparatus,
When the chip arrangement on the wafer and the arrangement of the optical system do not match, it has been difficult to simultaneously draw a pattern with a plurality of electron beams. In addition, this problem is not limited to the electron beam writing apparatus, but can be similarly applied to the ion beam writing apparatus.

The present invention has been made in view of the above circumstances, and an object thereof is to use a plurality of charged beams even when the arrangement of chips on a wafer does not match the arrangement of an optical system. An object of the present invention is to provide a multi-beam type charged beam writing apparatus and a writing method which can simultaneously write patterns without contradiction.

[0010]

[Means for Solving the Problems]

(Structure) In order to solve the above problems, the present invention employs the following structure. (1) In a multi-beam charged beam drawing system with multiple charged beam optical systems, logical operations are performed on the placement data of the chips to be formed on the wafer and the drawing area of each charged beam optical system, and the chips overlap. Means for obtaining a drawing area; means for forming drawing data for each drawing area of each charged beam optical system using the overlapping drawing areas as one chip; and paralleling the created drawing data to the corresponding charged beam optical system. And a means for simultaneously drawing by each charged beam optical system based on the transferred drawing data. (2) In (1), the means for creating drawing data for each drawing area extracts a pattern included in the overlapping drawing area from chip data, and extracts pattern data for each drawing area of each charged beam optical system. It is characterized by comprising means for creating and means for converting the pattern data into a drawing data format. (3) In (1), the means for generating drawing data for each drawing area includes means for converting chip data into data in a drawing data format,
Means for reconstructing the data in the drawing data format for each deflection area for each charged beam optical system as a chip. (4) In the above (3), the charged beam optical system employs a two-stage deflection system for beam deflection, and as a means for reconstructing the data in the drawing data format in units of deflection areas, an adjacent charged beam system is used. A sub-deflection area that straddles the drawing area boundary of the beam optical system is allocated to one of the charged beam optical systems. (5) In a drawing method using a charged beam drawing apparatus of a multi-beam system having a plurality of charged beam optical systems, a logical operation is performed on the arrangement data of chips to be formed on a wafer and a drawing area of each charged beam optical system. Performing a step of obtaining a drawing area overlapping with the chip; extracting a pattern included in the overlapping drawing area from the chip data to generate drawing data for each drawing area of each charged beam optical system; Converting the converted pattern data into data in the drawing data format, and transferring the converted drawing data to the corresponding charged beam optical systems in parallel,
Simultaneously performing drawing by each charged beam optical system based on the transferred drawing data. (6) In a drawing method using a multi-beam type charged beam drawing apparatus having a plurality of charged beam optical systems, a step of converting chip data into data in a drawing data format, and a layout data of chips to be formed on a wafer. And performing a logical operation on the drawing area of each charged beam optical system to obtain an overlapping drawing area. The drawing data for each charged beam optical system using the overlapping drawing area as one chip is converted into drawing data format data. Reconstructing in units of deflection areas, transferring the converted drawing data to the corresponding charged beam optical systems in parallel, and simultaneously drawing by each charged beam optical system based on the transferred drawing data. And performing the steps. (Operation) According to the configuration of (1), by setting the drawing area overlapping with the chip as one chip and generating the drawing data for each drawing area, the chip is larger than the drawing area of each charged beam optical system. Even in the case of a pattern, one chip (drawing data) always corresponds to one charged beam optical system. Therefore, even if writing is performed simultaneously by each charged beam optical system, writing can be performed without contradiction.

The configuration (2) can be easily realized by using a logical operation function used in normal CAD data design. In this case, the conversion of the created pattern data into the data in the drawing data format can be performed by a conventional electron beam drawing apparatus. It takes some time to convert a plurality of chip data to the drawing data format, but it can be dealt with by parallelizing the processing. Therefore, even if writing is performed simultaneously by each charged beam writing optical system based on these writing data, writing can be performed without contradiction.

In the configuration of (3), the conversion of the chip data into the drawing data format in advance can be performed by a conventional electron beam drawing apparatus. The method of obtaining an area where the chip arrangement data on the wafer and the drawing area of each charged beam optical system overlap can be easily realized by using a logical operation function used in normal CAD data design. At this time, it is assumed that the division of the chip data includes not only the chip arrangement but also information on the deflection area. In this way, the deflection area that straddles the drawing area boundary of each charged beam optical system when a logical operation is performed can be reliably allocated to each charged beam optical system.

For example, as shown in FIG. 7, the drawing area boundary 7 of the charged beam optical systems 70a, 70b, 70c, 70d
It is assumed that the deflection area 73 extending over the areas 1 and 72 is included in the drawing area 70b of the charged beam optical system including the origin of the area (here, the lower left of the area).

This makes it very easy to reconstruct the drawing data of each charged beam optical system for each deflection area. Therefore, it is not necessary to convert a plurality of chip data into the drawing data format, and the processing time is reduced. Even if processing is performed simultaneously by each charged beam optical system based on these drawing data, drawing can be performed without contradiction.

Further, according to the configurations of (5) and (6), even if the chip has a pattern larger than the drawing area of each charged beam optical system, one charged beam optical system must be used.
Since one chip (drawing data) corresponds, even if drawing is performed simultaneously by each of the charged beam optical systems based on these drawing data, drawing can be performed without contradiction.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. (First Embodiment) FIG. 1 is a schematic configuration diagram showing a multi-beam type electron beam writing apparatus according to a first embodiment of the present invention. In the figure, 10 is an electron optical column, 11 is an electron gun, 12 is an electron beam, 13 is a deflector, 14 is a sample chamber,
15 is a sample, 16 is a sample stage, 17 is a deflection control circuit, 18 is a stage control circuit, 20 is a control computer, 21
Denotes a drawing circuit, 22 denotes a drawing data processing unit, and 25 denotes a data input unit.

The accelerating voltage of the drawing apparatus is 1 kV. The drawable range is 150 mm square, and 15 × 15 pieces of 225 electron beam optical systems are arranged at a pitch of 10 mm. The beam deflection system has a main-sub two-stage configuration using electrostatic deflection, and the size of each deflection area is 5
00 μm and the sub deflection is 100 μm. The drawing area of each electron beam optical system is ± 5 mm around the electron gun,
This drawing area is drawn with 400 main deflection areas.

A description will be given of a drawing method in the present apparatus configured as described above.

First, chip arrangement data and chip data on a wafer are input from the data input unit 25 to the drawing data processing unit 22 of the control computer 20.

The drawing data processing unit 22 determines, by using a logical operation, an overlapping area between the drawing area of each electron beam optical system and the chip arrangement data on the wafer, and sets the overlapping area as one chip to write each electron beam optical system. Create data.

The created 225 pieces of drawing data are transferred to the drawing circuit 21 corresponding to each drawing area. Drawing circuit 2
1 corresponds to each electron optical system, and each drawing circuit 21
To transfer the drawing data in parallel to the corresponding electron beam optical system.

Thus, the drawing circuit 21 is connected to the stage system 1
6, 18 and the beam deflection systems 13 and 17 are driven to independently scan 225 electron beams to draw a pattern on the sample 15. If there is a drawing pattern in the corresponding main deflection area, a drawing scan is performed. At this time, when there is no drawing pattern in the corresponding drawing area or when there is no drawing pattern in the corresponding main deflection area, the beam is turned off. Since the drawing area is composed of 1 to 400 main deflection areas,
The stage was moved 400 times for convenience and drawing was performed.

Here, the above operation will be described in more detail with reference to FIG. Note that FIG. 2 shows a case in which the electron beams are arranged in an array of nine (3 × 3) systems for the sake of simplicity.

FIG. 5A shows the relationship between the drawing area of each electron beam optical system and the chip layout in this case. In the present embodiment, first, as shown in (b), a logical operation is performed on the chip layout information and the drawing area of each electron beam optical system. That is, the drawing area 211 is selected, and 221 to 22 are selected.
A logical operation with the chip layout information of No. 4 is performed. Here, areas that overlap each other are determined. By doing so, as shown in (c), portions overlapping each other are recognized as data. This is designated as design data 231.

Next, logical operations are sequentially performed on the drawing areas 212 to 219. By doing so, as shown in (d), the design data 231 to 2 corresponding to the drawing area
39 can be created.

The design data 231 to 239 are converted into drawing data 241 to 249 as one chip as shown in FIG. The data conversion at this time is
What is necessary is just to perform simultaneously with the conventional drawing data, making each drawing area one chip. That is, drawing is performed after performing preprocessing such as removing overlapping of figures permitted by CAD data, dividing a polygonal figure into rectangles and trapezoids, and performing black and white reversal of data if necessary. Main deflection matching the device configuration
It is divided into sub deflection areas. This makes it possible to create drawing data corresponding to each electron beam optical system. At this time, the coordinate system is converted into a system corresponding to the drawing area of each electron beam optical system. The drawing data 245 in the figure has a configuration in which different portions of four chips are combined into one chip. For example, it is reconstructed into a coordinate system having the lower left of each drawing area as the origin.

At the time of drawing, the created drawing data 24
1 to 249 are transferred to the corresponding electron beam optical system to perform drawing. In this case, the movement of the stage in the region beyond the main deflection is the same in the multi-beam type drawing apparatus as in the conventional drawing apparatus. Here, it is assumed that drawing is performed from the lower left as shown in (e). The drawing of the drawing area of each electron beam optical system is performed. First, the drawing data of the main deflection areas 251 to 259 is transferred to the drawing apparatus. When the drawing is completed, the drawing data of the main deflection region is transferred to the drawing device to draw the next main deflection region, and the drawing is performed.

As described above, according to the present embodiment, a logical operation is performed on the layout data of the chips to be formed on the wafer and the drawing areas of the respective electron beam optical systems, and the drawing areas overlapping with the chips are defined as one chip. By creating drawing data for each drawing area of each electron beam optical system, even if the chip size and the chip arrangement on the wafer are various and do not match the arrangement of the electron beam optical system, the necessary pattern can be Can be drawn simultaneously without inconsistency. For this reason, it is possible to significantly improve the drawing throughput. (Second Embodiment) The basic configuration of a multi-beam type electron beam writing apparatus according to this embodiment is the same as that shown in FIG. 1, but the writing data processing section 22 is configured as shown in FIG. I have. FIG. 4 shows a flowchart of the drawing process in this embodiment.

The following processing is performed by the drawing data processing unit in this embodiment. (1) The data 32 in which the chip data 30 is arranged based on the arrangement data 31 of the chip on the wafer is set in a CAD data format. (2) Create data 33 of drawing areas 1 to 225 of each electron beam optical system set in the CAD data format. (3) Data 33 of the drawing area from drawing area 1 to 225
And the logical operation of the chip and chip arrangement data 32
The operation was sequentially performed by the logical operation unit 34 (steps S1 to S3).
Here, a logical operation function used in normal CAD data design was used. (4) 255 data 35 recognized as drawing data
Is converted by the data conversion unit 36 into drawing data 37 in the data format of the drawing device (step S4). This technique was performed similarly to the conventional data conversion.

Thereafter, as in the first embodiment, the drawing data is transferred in parallel to each electron beam optical system (step S5), and drawing is performed simultaneously by each electron beam optical system (step S6). Become.

In this way, in a multi-beam type electron beam writing apparatus having a plurality of electron beam optical systems, the chip size and the arrangement of the chips on the wafer vary, and do not match the arrangement of the electron beam optical system. Even in such a case, it is possible to create drawing data corresponding to each electron beam optical system. Then, by using the drawing data created by the above-described method, it has become possible to draw simultaneously without contradiction in each electron beam optical system. (Third Embodiment) The basic configuration of a multi-beam type electron beam writing apparatus according to the present embodiment is the same as that shown in FIG. 1, but the writing data processing unit 22 is configured as shown in FIG. I have. FIG. 6 shows a flowchart of the drawing process in this embodiment.

The following processing is performed by the drawing data processing unit in this embodiment. (1) The chip data 51 is converted by the data converter 52 into data 53 which is a drawing data format of the drawing device (step S1). This is the same as the data conversion of the conventional electron beam writing apparatus. (2) The logical operation unit 54 checks the overlap between the arrangement data 55 of the chip on the wafer and the data 56 of the drawing area of each beam (step S2). At this time, the pattern was divided in the same unit of 100 μm as the sub-deflection region. As shown in FIG. 7, the sub-deflection region extending over the drawing region boundary of each electron beam optical system is included in the electron beam optical system including the origin of the region (here, the lower left of the region). And (3) Using the chip data 53 in the drawing data format and the 225 data 57 recognized as the drawing data as one chip, the data processing unit 58 reconfigures the drawing data 59 (steps S3 and S4). The data of the corresponding sub-deflection area may be selected from the chip data 53 already converted into the drawing data format and arranged in the drawing area of each electron beam optical system. At this time, the drawing area is divided into main deflection areas in the coordinate system of each electron beam optical system, and data of each sub deflection area is arranged in each main deflection area.

Thereafter, similarly to the first embodiment, the drawing data is transferred in parallel to each electron beam optical system (step S5), and is simultaneously drawn by each electron beam optical system (step S6). Become.

In this way, in a multi-beam type electron beam drawing apparatus having a plurality of electron beam optical systems, the chip size and the arrangement of the chips on the wafer are different and do not match the arrangement of the electron beam optical system. Even in such a case, it is possible to create drawing data corresponding to each electron beam optical system. Moreover, there is no need to perform data conversion for each drawing area of each electron beam optical system, and the time required for data conversion can be reduced. In addition, by using the drawing data created by the above-described method, it is possible to draw simultaneously without contradiction in each electron beam optical system.

The present invention is not limited to the above embodiments. In addition to the embodiments described above, the present invention is also applicable to a drawing apparatus of a type in which one beam is divided into a plurality of beams by an aperture. In the embodiment, the electron beam writing apparatus has been described. However, the present invention is not limited to this, and may be applied to an ion beam writing apparatus. In addition, various modifications can be made without departing from the scope of the present invention.

[0036]

As described above in detail, according to the present invention, a logical operation is performed on the arrangement data of the chip to be formed on the wafer and the drawing area of each charged beam optical system, and the drawing area overlapping with the chip is determined. By creating drawing data for each drawing area of each charged beam optical system as one chip, even if the chip size or the arrangement of chips on a wafer varies and does not match the arrangement of the electron beam optical system, a plurality of The pattern can be simultaneously drawn without contradiction by the charged beam. Further, the time required for data conversion can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a multi-beam type electron beam writing apparatus according to a first embodiment.

FIG. 2 is a schematic diagram for explaining the operation of the first embodiment.

FIG. 3 is a block diagram illustrating a configuration of a drawing data processing unit according to a second embodiment.

FIG. 4 is a flowchart for explaining the operation of the second embodiment.

FIG. 5 is a block diagram illustrating a configuration of a drawing data processing unit according to a third embodiment.

FIG. 6 is a flowchart for explaining the operation of the third embodiment.

FIG. 7 is a schematic diagram for explaining the operation of the present invention.

FIG. 8 is a schematic diagram for explaining a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electron optical column 11 ... Electron gun 12 ... Electron beam 13 ... Deflector 14 ... Sample chamber 15 ... Sample 16 ... Sample stage 17 ... Deflection control circuit 18 ... Stage control circuit 20 ... Control computer 21 ... Drawing circuit 22 ... Drawing Data processing unit 25 Data input unit 30, 51 Chip data 31, 55 Chip arrangement data 32 Chip and chip arrangement data 33, 56 Drawing area data 34, 54 Logical operation unit 35, 57 Drawing data Data recognized as 36, 52 Data conversion units 37, 59 Drawing data 53 Chip data in drawing data format 55 Arrangement data 58 Data processing unit

Claims (6)

[Claims] 1. A multi-beam type charged beam drawing apparatus having a plurality of charged beam optical systems, wherein a logical operation is performed on the arrangement data of a chip to be formed on a wafer and a drawing area of each charged beam optical system. Means for obtaining a drawing area that overlaps with, means for creating drawing data for each drawing area of each charged beam optical system using the overlapping drawing area as one chip, and a charged beam optical system corresponding to the created drawing data. A charged beam lithography system, comprising: means for transferring data in parallel to each other; and means for simultaneously drawing by each charged beam optical system based on the transferred drawing data. 2. A means for creating drawing data for each drawing area, extracting patterns included in the overlapping drawing areas from chip data, and creating pattern data for each drawing area of each charged beam optical system. 2. The charged beam lithography apparatus according to claim 1, further comprising: means for converting the pattern data into a writing data format. 3. The means for creating drawing data for each drawing area includes means for converting chip data into a drawing data format, and means for writing each of the charged beam optical systems each having the overlapping drawing area as one chip. 2. A charged beam drawing apparatus according to claim 1, further comprising means for reconstructing data in a data format in units of deflection areas. 4. The charged beam optical system according to claim 1, wherein beam deflection is performed in two stages of main and sub-deflection. As means for reconstructing the data in the drawing data format in units of deflection areas, an adjacent charged beam optical system is used. 4. The charged beam drawing apparatus according to claim 3, wherein the sub-deflection area spanning the drawing area boundary is assigned to one of the charged beam optical systems. 5. A drawing method using a multi-beam type charged beam drawing apparatus having a plurality of charged beam optical systems, wherein a logical arrangement is established between chip placement data to be formed on a wafer and a drawing area of each charged beam optical system. Performing a calculation, obtaining a drawing area overlapping with the chip, extracting patterns included in the overlapping drawing area from the chip data, and creating drawing data for each drawing area of each charged beam optical system, Converting the created pattern data into data in a drawing data format, transferring the converted drawing data to the corresponding charged beam optical systems in parallel, and, based on the transferred drawing data, Simultaneously writing with a charged beam optical system. 6. A drawing method using a multi-beam type charged beam drawing apparatus having a plurality of charged beam optical systems, comprising: converting chip data into data in a drawing data format; Performing a logical operation on the placement data and the drawing area of each charged beam optical system to obtain an overlapping drawing area, and drawing data for each charged beam optical system using the overlapping drawing areas as one chip,
A step of reconstructing the drawing data format data in units of deflection areas; a step of transferring the converted drawing data to the corresponding charged beam optical systems in parallel; and a step of transferring each charged beam optical system based on the transferred drawing data. Simultaneously writing in a system.