JP3481017B2 - Charged particle beam exposure apparatus and exposure data processing method of the charged particle beam exposure apparatus - Google Patents

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 exposure apparatus and an exposure data processing method for the charged particle beam exposure apparatus, and more particularly to a blanking aperture array (B).
The present invention relates to a charged particle beam exposure apparatus using an AA (Blanking Aperture Array) and an exposure data processing method for the charged particle beam exposure apparatus.

In recent years, with the progress of semiconductor technology, the degree of integration of semiconductor integrated circuits has increased. Then, a charged particle beam exposure apparatus using BAA is being researched as one for realizing higher integration of a semiconductor integrated circuit. However, the charged particle beam exposure apparatus using BAA requires a large amount of data (exposure data) and requires a long time for data development processing. Therefore, it is desired to provide a charged particle beam exposure apparatus that can reduce the exposure data and perform the data development processing in a short time, and an exposure data processing method for the charged particle beam exposure apparatus.

[0003]

2. Description of the Related Art Conventionally, the development of semiconductor technology has been remarkable,
Semiconductor integrated circuits (LSIs) have achieved four times higher integration in two to three years. Specifically, for example, a dynamic random access memory (DRAM: Dynamic)
Random Access Memory) has a storage capacity of 1
Mbyte, 4Mbyte, 16Mbyte, 64Mbyte,
It has increased to 256 Mbytes and 1 Gbyte,
High integration (large capacity) is advancing. L like this
The high integration of SI largely depends on the progress of fine processing technology in semiconductor manufacturing technology.

By the way, the charged particle beam exposure is 0.0
It is known that fine processing of 5 μm or less can be realized with alignment accuracy of 0.02 μm or less. However, conventionally, it has been considered that this charged particle beam exposure cannot be used for mass production of LSI due to its low throughput. The problem of the throughput in the charged particle beam exposure is, for example, a discussion about a single-stroke electron beam exposure in which one particle beam (electron beam) is continuously scanned and exposed.
Clarify the cause by focusing on the physical / technical neck,
It is not the result of serious consideration. That is, the fact that the charged particle beam exposure has a low throughput and cannot be used for mass production of LSIs is merely determined in view of the productivity of currently marketed devices.

On the other hand, in recent years, the present inventors have proposed
Block exposure and multi-beam blanking
By applying the aperture array exposure, for example,
1 cm ²Charged particles that enable throughput of approx./sec
Beam exposure equipment has come to be expected. Figure
10 is a charged particle proposed by the present inventors.
FIG. 2 is a block diagram schematically showing an example of a child beam exposure apparatus.
Shows an electron beam exposure system that uses an electron beam
There is.

As shown in FIG. 10, a semiconductor wafer 10 as an exposure object (sample) is placed on a moving stage 12, and the moving stage 12 is controlled to move by a stage control circuit 14. Here, the moving stage 12
The position of is detected by the laser interferometer length measuring device 16 and is fed back to the stage control circuit 14 to control the movement of the stage 12. Further, a resist film is deposited on the semiconductor wafer 10, and the electron beam exposure is performed by irradiating the resist film with the electron beam EB2 passing through the circular aperture of the aperture plate 18. It has become.

The electron beam E on the semiconductor wafer 10
The scanning of B2 is performed by moving the moving stage 12 and the moving stage 1
It is performed by an electromagnetic type main deflector (Major Defector) 20 and an electrostatic type sub-deflector (Minor Defector) 22 which are arranged above 2. Note that the movable stage 12, the main deflector 20, and the sub deflector 22 are in the descending order of the scannable range with the required accuracy, but the reverse order is in the descending order of the scanning speed. The scanning as shown in FIG. 11 is performed by utilizing such a property.

FIG. 11 is a view for explaining beam scanning in the charged particle beam exposure apparatus of FIG. That is, as shown in FIGS. 10 and 11, the main deflector 2
The electron beam EB2 is continuously deflected by 0 in the main scanning direction D1, and in parallel with this, the moving stage 12 is continuously moved in the sub-scanning direction D2 orthogonal to the main scanning direction D1. Further, the electron beam EB2 follows the movement of the moving stage 12 by the sub-deflector 22 so that the band A2, which is an area obtained by scanning the exposure area A0 by one main scan, is in the direction D1 on the semiconductor wafer 10. Is continuously deflected to. For example, the size of one band is 2mm in length and 10μ in width.
m, and one band scanning time is 100 μs. In this case, the moving speed of the moving stage 12 in the Y direction is 10 μm /
100 μs = 100 mm / s.

In FIG. 11, the chip regions C1 to C11 on the semiconductor wafer 10 are exposed with the same pattern. The movement stage 12 is controlled to move so that the frame A4 in one chip indicated by the diagonal lines is sequentially exposed in the arrow direction, and the exposure dot data of the frame A4 is repeatedly used. FIG. 12 is a diagram for explaining the relationship between the beam scanning and the stage position in the charged particle beam exposure apparatus of FIG. 10, and FIG. 12 (A) shows the electron beam EB2 on the semiconductor wafer 10 by the main deflector 20. FIG. 12B shows the change in the position X, and FIG.
2 shows the detection position Y of the moving stage 12 and the sub-deflection distance Y-Yi on the semiconductor wafer 10 by the sub-deflector 22.

In FIG. 10, the main control circuit 24 supplies a target position to the stage control circuit 14, supplies a periodic sawtooth wave signal to the amplifier circuit 26, and sets the stage detection position Y from the laser interferometer 16. The band Y coordinate Yi, which will be described later, is received from the BAA (Blanking Aperture Array) control circuit 40, and the sub-deflection distance Y-Yi is supplied to the amplification circuit 28.
Supply a signal proportional to. The drive signals that have been current-amplified and voltage-amplified by the amplifier circuits 26 and 28, respectively, are supplied to the main deflector 20 and the sub-deflector 22.

FIG. 13 is a view showing a part of the back surface of the blanking aperture array in the charged particle beam exposure apparatus of FIG. A blanking aperture array (BAA) plate 30 is arranged above the aperture plate 18. This blanking aperture array plate 30 is shown in FIG.
As shown in FIG. 3, a plurality of openings 33 are formed in a zigzag pattern in the thin substrate 31. Furthermore, each opening 3
3, a pair of electrodes 34 and 35 are formed on the substrate 31 (rear surface), respectively, and the deflection of the electron beam passing through each opening 33 is controlled.

FIG. 14 is a block diagram showing the blanking aperture array and its control circuit in the charged particle beam exposure apparatus of FIG. 10, and FIG. 15 is a schematic diagram showing the main configuration of the blanking aperture array control circuit of FIG. 16 is a block diagram schematically showing a configuration of a main part of the write / read circuit shown in FIG.

As shown in FIG. 14, in the blanking aperture array plate 30, openings 33 are formed in a zigzag pattern in a region 32 of a thin substrate 31, and the openings 33 are formed on the substrate 31. A pair of common electrodes 34 and a blanking electrode 35 are formed in the, and the common electrodes 34 are connected to the ground line. An electron beam EB0 having a substantially uniform current density is projected onto the region 32, and the electron beam passing through the aperture 33 is set to 0 V when the potential of the blanking electrode 35 is set to 0 V.
As shown by 0, although it passes through the aperture of the aperture plate 18 (EB2), a constant potential V is applied to the blanking electrode 35.
When s is applied, the electron beam is deflected and blocked by the aperture plate 18 (EB1). Therefore, if the bit is 1 /
Blanking electrode 35 corresponding to 0 exposure dot data
A desired fine pattern can be exposed on the semiconductor wafer 10 by applying a potential of 0 / Vs, for example.

Here, for example, one opening 33 is a square having a side of 25 μm, and the opening 33 exposes a substantially square area having a side of 0.08 μm on the semiconductor wafer 10. . The Y direction is referred to as the longitudinal direction of the rows of the openings 33, and the apparent two rows of the openings 33 are defined as one row. The openings 33 are shown in three rows 20 for simplification in FIG.
Although there are columns, in practice, for example, it is configured to have about 8 rows and 128 columns.

The openings 33 are arranged in m rows and n columns, and the openings 33 and blanking electrodes 35 in the i-th row and the j-th column are respectively 33.
Represented as (i, j) and 35 (i, j). However, in FIG.
The reference numeral 33 (i, j) is omitted therein (the same applies to FIG. 15). The pitch p of the openings 32 in the X direction is, for example, three times the length a of one side of the openings 32 in order to secure a region for electrodes and wiring.

FIG. 17 is a diagram schematically showing the relationship between the exposure pattern and the blanking aperture array area.
A part of the wiring pattern of the RAM is shown in association with the size of the area 32. The exposure dot data of the frame A4 is set to the lengths PX and Y in the X direction on the pattern.
The exposure dot data of the block corresponding to the rectangular area having the length PY in the direction is divided. This division is performed so that the number of repetitions increases in frame A4. However, the pitch PY is equal to or less than the length PYm of the region 32 in the Y direction, and
Try to be as long as possible. The pitch PY is
Band A2 divided by an integer, in other words band A
The length of 2 is set to be an integral multiple of the pitch PY and within a range in which scanning can be performed with required accuracy. This rectangular area is shown in FIG.
The inner cell stripe A1 is used. In FIG. 17, one frame A4 delimited by the one-dot chain line corresponds to one memory cell, and this exposure dot data is repeated.

The region 32 is divided in the Y direction into a region A0 corresponding to the cell stripe A1 and regions 37 and 38 on both sides thereof, and a potential Vs is applied to the blanking electrodes 35 in the regions 37 and 38. To supply. Next, the BAA control circuit 40 will be described with reference to FIG.
The BAA control circuit 40 is provided with a dot memory 41j corresponding to the blanking electrodes 35 in the j-th column (j = 1 to n). The dot memories 411 to 41n have the same storage capacity.

The writing / reading circuit 42 designates a common address for the dot memories 411 to 41n based on the clock and the control signal from the control circuit 43 which operates in synchronization with the clock φ0, and causes the main control circuit 24 to specify the common address. The supplied exposure dot data is written or the written exposure dot data is read. Each of the dot memories 411 to 41n is divided into a plurality of areas, for example, two areas, and the exposure dot data is written to one area by the direct memory access method, while the exposure dot data is read from the other area. Each time reading and writing of one frame A4 is completed, both areas are switched between the reading area and the writing area. The data corresponding to the areas 37 and 38 in FIG. 17 are all set to "0".

A read / write control signal for the dot memories 411 to 41n is supplied from the control circuit 43.
The exposure dot data read from the dot memory 41j is supplied to the least significant bit of the shift register 44j. The shift register 44j is shifted to the upper side by 1 bit in 1 clock from the control circuit 43. This clock cycle T is the same as the bit read cycle from the dot memory 41j.

As is apparent from FIG. 15, the blanking electrode 35 (i, j) is connected to the power supply wiring or the ground line of the potential Vs via the contactless switch element of the buffer circuit 45, and the control of this switch element is performed. The k-th bit output terminal (the lowest bit is 0) of the shift register 44j is connected to the input terminal. Here, k is the above p and a. When j is an odd number, k = 2 (p / a) (i-1). When j is an even number, k = (p / a) (2i-1). Becomes

The k-th bit of the shift register 44j is 1 /
When 0, the potential of the blanking electrode 35 (i, j) is 0 /
The electron beam that has been applied with Vs and has passed through the opening 33 (i, j) is irradiated onto the semiconductor wafer 10 only when this potential is zero. The scanning speed of the electron beam in the X direction is t = 0.
When the electron beam passing through the opening 33 (i, j) irradiates the point P on the semiconductor wafer 10 at time t = 2 (p /
a) T, 4 (p / a) T, ..., 2 (m-1) (p /
a) Open holes 33 (2, j), 33 (3, 3) at T, respectively.
The electron beams passing through j), ..., 33 (m, j) are adjusted so as to irradiate the same point P on the semiconductor wafer 10.

As a result, the same point on the semiconductor wafer 10 is exposed m times with the same data. Also, the opening 33
(I, j), j = 1, 3, 5, ..., N−1, and between the dots exposed at the time point t, the aperture 33 (i, j),
Through j = 2, 4, 6, ..., N, time point t + (p /
a) T exposure. Next, the write / read circuit 4
An example of the configuration of the read circuit 421 included in No. 2 will be described with reference to FIG.

The read circuit 421 includes an up / down counter 50, a band memory 51, an up counter 52, a cell stripe memory 53, registers 54 to 56, an arithmetic circuit 57 and an up counter 58. In the band memory 51, the Y coordinate of the band A2 shown in FIG.
The cell stripe head address AS0 is stored correspondingly. The cell stripe start address AS0 is an address on the cell stripe memory 53 corresponding to the first cell stripe A1 of the band A2. The band memory 51 is addressed by the count value AB of the up / down counter 50.

The load signal, the clock φ1 and the up / down control signal are supplied from the control circuit 43 to the load control input terminal L, the clock input terminal CK and the up / down mode input terminal U / D of the up / down counter 50, respectively. It The up-down counter 50 is loaded with an initial value when the load control input L is active. This initial value is used for the band memory 51 when the up / down mode input terminal U / D is at high level and is in the count up mode.
It is the top address AB0 of the first band above, and is the address ABE of the last band on the band memory 51 when the up / down mode input terminal U / D is at the low level and in the countdown mode. The start address AB0 and the end address ABE are respectively the frame A4 shown in FIG.
Corresponding to positions B0 and BE.

When the up / down counter 50 is loaded with the initial value, the down counter 431 in the control circuit 43 is loaded with the number of bands ABN0 = E + 1. The count value ABN of the down counter 431 is decremented by 1 each time the clock φ1 rises. When the count value ABN of the down counter 431 becomes 0, the exposure of one frame A4 is completed.

The cell stripe head address AS0 read from the band memory 51 is loaded into the up counter 52 by a load signal from the control circuit 43 as an initial value. The band Y coordinate Yi read at the same time as the cell stripe start address AS0 is supplied to the main control circuit 24 in FIG. The up counter 52 is the control circuit 4
The clock φ2 from 3 is counted, and the cell stripe memory 53 is addressed by the count value AS.

When the up counter 52 is loaded with the initial value AS0, the down counter 432 in the control circuit 43 is loaded with the number of cell stripes ASN0 in one band. The count value ASN of the down counter 432 is decremented by 1 each time the clock φ2 rises. When the count value ASN of the down counter 432 becomes 0, the exposure of one band A2 ends, the clock φ1 rises at the same time, and the next cell stripe start address AS0 is loaded into the up counter 52.

The cell stripe memory 53 stores a cell stripe number as a code for identifying the cell stripe A1. For example, when AS0 = S1,
Count value AS is cell stripe start address S1 to S2
The cell stripe numbers N10 to N13 corresponding to A10 to A13 in FIG. 11 are read from the cell stripe memory 53 by incrementing by one to −1.

The output N of the cell stripe memory 53 is held in the register 54. On the other hand, the register 55 has 1
The number of dots A in the X direction of one cell stripe A1 is held, and the base address B is held in the register 56. The arithmetic circuit 57 calculates the head address A · N + B based on these N, A and B, and the up counter 58.
Supply to. The head address A · N + B is loaded to the up counter 58 as an initial value by a load signal from the control circuit 43. The up counter 58 counts the clock φ3 from the control circuit 43, and the dot memory 411 is addressed by the count value AD.

When the initial value A · N + B is loaded into the up counter 58, the down counter 43 in the control circuit 43 is loaded.
The number ADN0 of dots in the X direction in one cell stripe is loaded in No. 3. The count value ADN of the down counter 433 is
It is decremented by 1 at each rising edge of the clock φ3. When the count value ADN of the down counter 433 becomes 0, the exposure of one cell stripe A1 is completed, and at the same time, the clock φ2 rises and the next cell stripe number A.
N + B is loaded into the up counter 58.

The data in the band memory 51 and the cell stripe memory 53 are the dot memories 411 to 41n.
Similarly to the exposure dot data in (1), it is created in advance as a part of the exposure data, stored in the external storage device, and loaded from the external storage device. According to the present embodiment, when the exposure dot data of the block corresponding to the cell stripe A1 is the same, by designating this block by the same cell stripe number N, the same exposure dot data is repeatedly used. The amount of data can be reduced.
As a result, the exposure data transfer time from the external storage device such as a hard disk to the memory is shortened, and the throughput of the exposure device is improved.

Further, since the band memory 51 is used, it is only necessary to specify the same cell stripe start address for the band A2 of the same exposure dot data.
As a result, it becomes unnecessary to repeatedly store the same cell stripe number sequence in the cell stripe memory 53, and the amount of exposure data can be further reduced. Also, for example,
Although the scanning directions of the frame A4 are opposite between the chip areas C1 and C2 of FIG. 11, the up / down counter 50 of FIG.
This can be dealt with only by changing the up / down mode and the initial value, and the amount of exposure data can be further reduced.

In the rectangular division of the frame A4 which is processed before writing to the dot memory, the pitch P is set to increase the number of repetitions and the pitch PY as much as possible.
It is sufficient to make X and PY variable. In this case, in FIG. 17, since it is necessary to make the width of one band A2 constant, the pitch PY is made variable in units of the cell A3 composed of an integral number of bands A2. Cell A3 may match frame A4. Since the number of dots (the number of bits) of one cell stripe A1 in the X direction (main scanning direction) changes depending on the pitch PX of the cell stripe A1, that is, the value of the register A changes, the address range A · N + B ~
The value of N is skipped as necessary so that A. (N + 1) + B-1 does not overlap, that is, N + 1 is used instead of N, or the base address B is changed.

[0034]

As described above, in the charged particle beam exposure apparatus as a related technique of the present invention, which is being researched and developed by the present inventors, fineness, alignment accuracy, quick turnaround, Also, in terms of reliability, etc., it is considered to be superior to other semiconductor exposure methods. However, the charged particle beam exposure apparatus of this related technique is still not sufficiently satisfactory in reality because the amount of exposure data is still large and the data expansion process requires a long time.

By the way, in the charged particle beam exposure apparatus, data for changing the shape by shifting the proximity effect correction to the pattern itself or changing the exposure amount of the pattern is created and the pattern is exposed. By doing so, proximity effect correction is performed. Even in the BAA type exposure apparatus, it is possible to perform exposure using conventional pattern data. However, in this conventional data, the proximity effect correction is different for each pattern and has a one-to-one correspondence. As the size of the storage device increases, a large-capacity storage device is required. Further, when expanding to a bitmap, there is a problem to be solved that the expansion process requires a long time because of the large amount of data and the process of converting the exposure amount correction into bit data also takes time. is there.

Regarding the verification of the data (exposure data), the data subjected to the proximity effect correction often has a different shape from the design data, which makes the verification of the data very difficult. There is. In view of the problems of the charged particle beam exposure apparatus machine translation apparatus as the related art described above, the present invention further reduces the exposure data,
An object of the present invention is to provide a charged particle beam exposure apparatus and an exposure data processing method for the charged particle beam exposure apparatus, which can reduce the time required for data development processing. Another object of the present invention is to provide a charged particle beam exposure apparatus which can easily perform proximity effect correction and can perform data verification, and an exposure data processing method for the charged particle beam exposure apparatus.

[0037]

According to a first aspect of the present invention, there is provided a charged particle beam exposure apparatus for forming a predetermined exposure pattern on a sample 10 using a charged particle beam EB. For generating charged particle beam 100, an aperture 33 arranged in the optical path of the charged particle beam from the charged particle beam generator, for shaping the cross-sectional shape of the charged particle beam, and passed through the aperture. The proximity effect is applied to the blanking aperture array 30 in which a plurality of aperture passing beam deflecting means 34 and 35 for deflecting the aperture passing beam are arranged in a zigzag pattern, and the exposure pattern data previously bit-developed. Data expansion means 200 for performing calculation using proximity effect correction data for correction and creating bit expanded data including proximity effect correction.
The pattern data for the proximity effect correction,
Pre-register as fruit correction bitmap data, and
Provided is a charged particle beam exposure apparatus characterized by being adapted to a pattern region . The second of the present invention
According to the morphology, the charged particle beam EB is used to
Charged particle beam exposure device that forms a predetermined exposure pattern on the
And a charged particle beam for generating a charged particle beam
Generating means 100 and a load from the charged particle beam generating means
The charged particle beam is arranged in the optical path of the charged particle beam.
An opening 33 for forming a cross-sectional shape and an opening passing through the opening
Aperture passing beam deflection means 34 for deflecting the aperture passing beam,
Blanking appa in which 35 are arranged in a zigzag pattern
-Charger array 30 and exposure pattern that has been bit-developed in advance
Proximity to correct proximity effects for data
Proximity effect correction is performed by performing calculations using effect correction data.
Data expansion means 200 for creating bit expansion data including
And to perform the proximity effect correction of the exposure pattern.
Specified pattern data for
Data addition, subtraction, or multiplication
Addition, subtraction, or multiplication of
To have as the calculation information in the data of the exposure pattern,
At the time of exposure, bit expansion is performed according to the calculation information.
There is provided a charged particle beam exposure apparatus characterized by
It

According to the third aspect of the present invention, a plurality of units each having a zigzag pattern are formed, each unit including an opening for shaping the cross-sectional shape of the beam and a means for deflecting the beam associated with the opening. A particle beam is irradiated to the ranking aperture array to form a beam bundle, and whether or not it passes through the aperture of the round aperture further inside the beam barrel is applied to the beam deflecting means attached to the aperture. The charged particle beam exposure apparatus that scans and exposes the exposure target while controlling whether the beam formed by each aperture reaches the sample by controlling the voltage A method for processing exposure data of a charged particle beam exposure apparatus, which decomposes bit development data on the apparatus side before exposure, stores it in a storage device, and sequentially discharges and exposes it. The proximity correction pattern has a correction component as the pattern data, and performs a predetermined operation on the pattern data of the area to be corrected so as to obtain a final bit expanded data, performs the proximity effect correction Pas
Turn data as bitmap data for proximity effect correction
And register in advance so that it corresponds to multiple pattern areas
Exposure data processing method of a charged particle beam exposure apparatus being characterized in that the is provided. According to the fourth aspect of the present invention
If so, an opening for forming the cross-sectional shape of the beam and the opening
Houndstooth unit consisting of means for incidentally deflecting the beam
Blanking aperture array
The particle beam is irradiated to form a beam bundle, and the beam
Inside the lens barrel, open the round aperture opening further ahead.
Beam deflecting means associated with the aperture whether to pass or not
The shape of each aperture is controlled by controlling the voltage applied to
Control whether the formed beam reaches the sample or not
Meanwhile, the charged particle beam that scans and exposes the exposure target
The exposure pattern data before exposure
Is decomposed on the device side as bit expanded data and stored in a storage device.
Charged particle beam exposure apparatus that stores and sequentially discharges and exposes
Exposure data processing method of
Result correction is performed by using the correction component as pattern data
Perform predetermined calculation on the pattern data of the area
To obtain the final bit expanded data,
Set the pattern data for effect correction to the proximity effect correction bit.
Pre-registered as map data, multiple pattern areas
The charged particle beads are characterized in that
An exposure data processing method for a system exposure apparatus is provided.

[0039]

According to the charged particle beam exposure apparatus of the present invention, a charged particle beam generating means 100 generates a charged particle beam, and blanking is performed in the optical path of the charged particle beam from the charged particle beam generating means. An aperture array 30 is arranged. The blanking aperture array 30 has openings 33 for shaping the cross-sectional shape of the charged particle beam.
Further, a plurality of aperture passing beam deflecting means 34, 35 for deflecting the aperture passing beam passing through the apertures are arranged in a zigzag pattern. Then, the data developing means 200 in the charged particle beam exposure apparatus of the present invention performs an operation using the proximity effect correction data to correct the proximity effect on the exposure pattern data which has been bit expanded in advance. ing.

As a result, according to the charged particle beam exposure apparatus of the present invention, it is possible to reduce the exposure data and perform the data expansion processing within a short time. Further, according to the exposure data processing method of the charged particle beam exposure apparatus of the present invention, the exposure pattern data is decomposed on the apparatus side as bit development data before exposure and stored in the storage device, and then from the storage device. The particles are sequentially discharged and the charged particle beam exposure is performed. Then, the proximity effect correction of the exposure pattern has a correction component as pattern data, and by performing a predetermined calculation on the pattern data of the area to be corrected, final bit expansion data can be obtained. .

As a result, according to the exposure data processing method of the charged particle beam exposure apparatus of the present invention, it is possible to reduce the exposure data and perform the data expansion processing within a short time.

[0042]

Embodiments of a charged particle beam exposure apparatus and an exposure data processing method for the charged particle beam exposure apparatus according to the present invention will be described below with reference to the drawings. 1 and 2 are block diagrams showing a configuration example of a charged particle beam exposure apparatus (BAA type electron beam exposure apparatus) according to the present invention. 1 and 2, reference numeral 100 is a charged particle beam generating means (electron gun), 200 is a data expansion unit, 2
10 is a first storage device, 220 is a second storage device, 23
0 is memory (dot memory) and 240 is BAA
The voltage application control circuit is shown. Also, reference numeral 301
Is a data management CPU, 302 is an exposure control CPU, 3
Reference numeral 03 is an exposure management unit, 304 is a time keeper, 305 is a refocus control unit, 306 is a stage management unit for managing the moving stage 12, and 307 is a loader management unit. Here, the refocus control unit 305
The refocusing coil 331 is controlled to control the electron beam EB2.
(EB) refocusing is controlled, and
The loader management unit 307 is for controlling the loader 321 for exchanging semiconductor wafers mounted on the moving stage 12.

The electron beam E output from the electron gun 100
The semiconductor wafer 10 mounted on the moving stage 12 is irradiated with B through the blanking aperture array 30 and the aperture plate 18. Where the electron beam E
B (EB2) is a blanking control coil 334, a refocusing coil 331, a stigma coil 332,
And with the focus coil 333 and the optical control by the main deflector 20 and the sub-deflector 22, etc.,
The exposure pattern is controlled by the blanking aperture array 30 and the like described with reference to FIGS. 11 to 17. Here, the blanking control coil 334 is for controlling whether or not the entire electron beam having a predetermined pattern by the blanking aperture array 30 passes through the circular aperture of the aperture plate 18 as it is. The stigma coil 332 is for correcting astigmatism of the optical system.

The blanking aperture array 30 in the charged particle beam exposure apparatus of FIGS.
The structures of the aperture plate 18, the main deflector 20, the sub deflector 22, and the moving stage 12 on which the semiconductor wafer 10 is mounted are the same as those described with reference to FIG. Is omitted. In this embodiment,
The data expanding unit 200 performs an operation using the proximity effect correction data for correcting the proximity effect on the exposure pattern data that has been bit expanded in advance, and creates bit expanded data including the proximity effect correction. Has become.

In the charged particle beam exposure apparatus shown in FIGS. 1 and 2, the exposure pattern data is created in a predetermined data format and stored in the first storage device 210 on the exposure apparatus side. The data to be exposed is 0, 1 (beam O
The data expansion circuit 200 sequentially expands the bit expansion data represented by (N / OFF). Here, in the data expansion circuit 200, addition, subtraction, multiplication, etc. of the pattern (including the proximity effect correction pattern) held as the bitmap data are also executed by the information to become expanded data.

Further, the expanded data is stored in the second storage device 220. The second storage device 220 is
It is defined corresponding to the opening of BAA. Where the first
The storage device 210 and the second storage unit 220 are configured as, for example, a large-capacity hard disk device. Then, at the time of exposure, BA is read from the second storage device 220.
Data is sequentially transferred in parallel to the memory 230 corresponding to each aperture of A. Further, the transferred data is sequentially supplied from the memory 230 to the BAA voltage application control circuit 240 which controls whether or not a predetermined voltage is applied between the electrodes provided in each opening of the BAA, and the BAA is used. The beam (beam passing through the aperture) is turned on / off to form a predetermined exposure pattern on the sample (sample to be irradiated: semiconductor wafer, for example).

FIG. 3 is a diagram showing an example of a data structure to which the exposure data processing method of the charged particle beam exposure apparatus according to the present invention is applied. FIG. 3A shows pattern data of a figure, and FIG. b) shows the pattern data of the bitmap, and FIG. 6C shows the proximity effect correction data of the bitmap. As shown in FIGS. 3A to 3C, as the pattern data, graphic data of a real pattern showing a relatively simple shape such as a triangle and a rectangle, and a real data which is repeatedly used a plurality of times. There are bitmap data for patterns and bitmap data for proximity effect correction. The data discriminating unit discriminates these data. Here, each of the pattern data is stored in the first storage device 210. Further, as the data for the proximity effect correction, not only bitmap data but also graphic data as shown in FIG. 3A can be used.

The graphic data shown in FIG. 3A is, for example, a triangle, a rectangle, or an arbitrary angular graphic, and has a normal starting point position (starting point X, starting point Y) and size (size X). , Size Y), which defines a predetermined shape. The actual pattern (bitmap) shown in FIG. 3B corresponds to, for example, a predetermined unit area cut out when a similar pattern of a memory or the like is repeated, and corresponds to a data start point position (start point X , Starting point Y), and the number of the data, the local cutout information is obtained. Then, as shown in FIG. 3C, the proximity effect correction pattern (bitmap data) also has the same starting point position (starting point X, starting point Y) of the data and the same as the actual pattern of the bitmap. It is represented by a number so that the local cutout information can be obtained. Here, the proximity effect correction pattern is
Calculation information is included in the data discrimination.

The pattern data shown in FIGS. 3 (a) to 3 (c) is formed by data processing for each deflection area, and in the data processing, it is cut out into a pattern figure. . 4A and 4B are diagrams showing an example of an exposure pattern and an example of a bitmap corresponding to the exposure pattern. FIG. 4A shows an example of a unit area pattern and FIG. 4B shows a unit area pattern. FIG. 3C shows bitmap data obtained by expanding a pattern into a bitmap, FIG. 7C shows a repetitive pattern cutout process, and FIG. 6D shows a local selection process in a unit area pattern. Here, as shown in FIGS. 4A and 4B, the area where the exposure pattern exists is replaced with data “1”, and the area where the exposure pattern does not exist is replaced with data “0”. Then, the bitmap data is created. The data “1” indicates the area where the electron beam is irradiated by controlling each electrode of the blanking aperture array 30, and the data “0” indicates that the electron beam is irradiated by controlling each electrode of the blanking aperture array 30. The area not irradiated is shown.

As shown in FIGS. 4A to 4D, for example, in the case where a pattern of a certain unit such as a memory pattern is repeated, the pattern of the same unit is cut out in the unit area. I'm supposed to find it. The unit cut out in this unit area is managed by a number, the same unit area is given the same number, and one data is registered in one number. Furthermore, if the unit is represented by 1,0 as bitmap data, and if there is a local shape that is the same as the pattern shape in the unit area, the pattern is also assigned the same number and the local cutout information is It is supposed to be added.

FIG. 5 is a diagram for explaining the proximity effect correction by the exposure data processing method of the charged particle beam exposure apparatus of the present invention. FIG. 5A shows the bitmap data of the exposure pattern (before proximity effect correction). Data), and FIG.
Indicates the bitmap data of the proximity effect correction pattern,
Then, FIG. 7C shows bitmap data of the exposure pattern after the proximity effect correction (data after the proximity effect correction).

As shown in FIGS. 5A to 5C, when the proximity effect correction is performed, the bitmap data for the proximity effect correction is set to the bitmap data for the exposure pattern (actual pattern). In addition, the expanded data after the proximity effect correction is obtained. Here, the data of the area to be exposed by the proximity effect correction is set to "1", but when the area of the data "1" by the proximity effect correction overlaps the area of the data "1" in the exposure data, In the corrected expanded data that has been expanded into bits (see FIG. 5C),
The area becomes data “2 (for example, decimal display)”.
However, like the other data "1" areas, the data "2" areas are exposed as the data "1" by electron beam irradiation under the control of each electrode of the blanking aperture array 30. become. Here, FIG. 5 shows the case where the bitmap data of the proximity effect correction is added to the exposure pattern (bitmap data), but the calculation of the proximity effect correction for this actual pattern is not limited to the addition. Of course, it may be performed by subtraction, multiplication, or the like.

FIG. 6 is a diagram for explaining the flow of processing to which the exposure data processing method of the charged particle beam exposure apparatus of the present invention is applied. FIG. 6A shows a concrete example of the data format, The figure (b) shows the state of management of the bitmap data, and the figure (c) shows the bitmap data after expansion. FIG. 6A shows the above-mentioned FIG. 3A.
-The graphic data described with reference to FIG.
(A)), bitmap data (see FIG. 3 (b)), and proximity effect correction patterns (see FIG. 3 (c)) are shown as an example of a data format (pattern data).
In addition, FIG. 6B is a diagram of FIG. 3A to FIG. 3C described above.
The concept of the management of the bitmap data by the data number, the starting point, and the number of data (local cutout information) described with reference to FIG. 3 is shown, and the graphic data (see FIG. 3A) and the bitmap data (see FIG. FIG. 3B), and an example of pattern data having a proximity effect correction pattern (see FIG. 3C). Then, FIG. 6C is the same as FIG.
An example of bitmap data showing a state where the proximity effect correction pattern is applied to the actual pattern (bitmap) shown in (b), that is, local correction is performed is shown.

FIG. 7 is a diagram for explaining a state in which a plurality of correction patterns are superimposed on a predetermined pattern in the present invention, and is a diagram showing an enlarged part of a cell stripe. Further, FIG. 8 is a diagram showing a state in which the correction data used in FIG. 7 is cut out from the memory registration correction data. The correction of the actual data (exposure pattern data) by the proximity effect correction pattern (bitmap data) described above can be performed using, for example, a plurality of correction data (proximity effect correction patterns) as shown in FIG. 7. it can. That is, as shown in FIG. 8, three proximity effect correction patterns (bitmap patterns) having different correction data 1 from the address a, correction data 2 from the address b, and correction data 3 from the address c are implemented. Proximity effect correction is performed by applying it to data (bitmap pattern).

Here, in the proximity effect correction, for example, correction data 1 to correction are made so as to correspond to a plurality of pattern areas from the proximity effect correction bitmap data registered in advance in the first storage device 210 in FIG. The data 3 is cut out so as to correspond to the actual pattern. Further, the proximity effect correction bitmap data is configured to read and use an arbitrary area in the bitmap data registered in advance. In other words, as this proximity effect correction bitmap data, necessary dot patterns are read from the areas having various dot patterns and used as proximity effect correction bitmap data so that various proximity effects can be corrected. It is supposed to do. The proximity effect correction can also be performed by shift-correcting the correction data 3 (rectangular shape) shown in FIG. 8 and using the corrected correction data 3 (diamond shape: see FIG. 7). Further, the correction data is, for example,
It is also possible to apply a plurality of patterns partially overlapping. Further, the proximity effect correction for the exposure pattern (actual data) may be performed not only by addition of the proximity effect correction pattern but also by subtraction or multiplication. Further, the addition, subtraction, multiplication, etc. of the bitmap data can be configured to be carried by the proximity effect correction pattern itself as calculation information in the exposure pattern data.

FIG. 9 is a block diagram showing an example of the configuration of the data expansion section 200 in the charged particle beam exposure apparatus of the present invention. In the figure, reference numeral 201 is an expansion control unit, 202 is a block data memory, 203 is a data generation unit, 204 is a selection unit, 205 is a shift unit, 206
Is a calculation unit, 207 is a canvas memory, and 208
Indicates a transfer unit.

The expansion control unit 201 includes a CPU 30 for managing data and data from the first storage device 210.
Command is received, pattern data is analyzed and discriminated, and data expansion is controlled. Block data memory 20
Reference numeral 2 is adapted to load and hold data (bitmap data) from the first storage device 210, and the data generator 203 generates graphic data such as triangles and rectangles. , Is composed of a hardware circuit.

The selection unit 204 is configured to use the block data memory 2
02 or one output of the data generating section 203 is selected and supplied to the shift section 205. The shift unit 205 shifts the output data of the selection unit 204 in, for example, the X direction, shift-converts the correction data 3 (rectangular dot pattern) shown in FIG. The correction data 3 (diamond-shaped dot pattern) after shift conversion as shown corresponds to the actual pattern. Here, the actual pattern is stored in the canvas memory 207, and the correction data (for example, the correction data 1 to 3 illustrated in FIG. 7) used for the proximity effect correction is the actual pattern (proximity effect) in the canvas memory 207. The exposure pattern data before correction) is overwritten.

The calculation unit 206 has a canvas memory 207.
After the data stored in (drawn) is once read, for example, calculations such as addition and subtraction of correction data for proximity effect correction are performed. Will be overwritten. The thus rewritten data in the canvas memory 207 (exposure pattern data after proximity effect correction) is transferred to the second storage device 220 via the transfer unit 208.

As described above, in the present embodiment, the proximity effect correction processing divides the deflection area into several small areas, obtains the correction pattern of the area, and holds it as bitmap data, which is expanded at the time of exposure. In the circuit, bit expansion data is obtained by combining with the pattern data based on the operation information. Further, according to the charged particle beam exposure apparatus and the exposure data processing method of the charged particle beam exposure apparatus of the present embodiment, the proximity effect correction has the correction component registered in advance as pattern data and has the bitmap data. Therefore, there is no need to deploy,
Since there is calculation information such as addition, correction is performed by calculating with a pattern that requires correction. Since the pattern data is not changed, the verification is easy. As described above, normal pattern data can also be held as bitmap data, and the amount of data can be reduced. Also,
Since the bitmap data has a structure that can be referred to from a plurality of pattern areas and can be partially referred to, the data amount can be reduced.

[0061]

As described above in detail, according to the charged particle beam exposure apparatus and the exposure data processing method of the charged particle beam exposure apparatus of the present invention, the exposure data is reduced and the data expansion processing is shortened. Can be done within.

[Brief description of drawings]

FIG. 1 is a block diagram (No. 1) showing a configuration example of a charged particle beam exposure apparatus according to the present invention.

FIG. 2 is a block diagram (No. 2) showing one configuration example of the charged particle beam exposure apparatus according to the present invention.

FIG. 3 is a diagram showing an example of a data structure to which the exposure data processing method of the charged particle beam exposure apparatus according to the present invention is applied.

FIG. 4 is a diagram showing an example of an exposure pattern and an example of a bitmap corresponding to the exposure pattern.

FIG. 5 is a diagram for explaining proximity effect correction by the exposure data processing method of the charged particle beam exposure apparatus of the present invention.

FIG. 6 is a diagram for explaining the flow of processing to which the exposure data processing method of the charged particle beam exposure apparatus of the present invention is applied.

FIG. 7 is a diagram for explaining how a plurality of correction patterns are superimposed on a predetermined pattern in the present invention.

FIG. 8 is a diagram showing how the correction data used in FIG. 7 is cut out from the memory registration correction data.

FIG. 9 is a block diagram showing a configuration example of a data expansion unit in the charged particle beam exposure apparatus of the present invention.

FIG. 10 is a block diagram schematically showing an example of a charged particle beam exposure apparatus.

FIG. 11 is a diagram for explaining beam scanning in the charged particle beam exposure apparatus of FIG.

12 is a diagram for explaining the relationship between beam scanning and stage position in the charged particle beam exposure apparatus of FIG.

13 is a diagram showing a part of the back surface of the blanking aperture array in the charged particle beam exposure apparatus of FIG.

14 is a block diagram showing a blanking aperture array and its control circuit in the charged particle beam exposure apparatus of FIG.

15 is a block diagram schematically showing a main part configuration of a blanking aperture array control circuit in FIG.

16 is a block diagram schematically showing a main part configuration of a write / read circuit in FIG.

FIG. 17 is a diagram schematically showing a relationship between an exposure pattern and a blanking aperture array region.

[Explanation of symbols]

10 ... Semiconductor wafer 12 ... Movement stage 18 ... Aperture plate 30 ... Blanking aperture array (BAA) 200 ... Data development unit 210 ... First storage device 220 ... Second storage device 230 ... Memory (dot memory) 240 ... BAA voltage application control circuit 301 ... CPU for data management 302 ... Exposure control CPU 303 ... Exposure management unit 304 ... Time Keeper

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichi Kai, Kanagawa Prefecture, Kawasaki City, Nakahara-ku, 1015 Kamiodanaka, Fujitsu Limited (72) Inventor Hiroshi Yasuda, Kanagawa Prefecture, Kawasaki City, Nakahara-ku, 1015, Kamikodanaka, Fujitsu Limited ( 56) References JP-A-5-267135 (JP, A) JP-A-60-262420 (JP, A) JP-A-6-163373 (JP, A) JP-A-7-78737 (JP, A) (58) ) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/027

Claims (21)

(57) [Claims] 1. A charged particle beam exposure apparatus for forming a predetermined exposure pattern to specimen using a charged particle beam, the charged particle beam generator means to generate a charged particle beam, the charged particle beam disposed in the optical path of the charged particle beam from the generating means, the opening passes the beam deflection means to deflect the apertures passing beam passed through the aperture you and the open hole for forming the cross-sectional shape of the charged particle beam a blanking aperture array over which a plurality arranged in a checkerboard pattern, to the data of the exposure pattern that is pre-bit expansion,
Performs a calculation using the proximity effect correction data for correcting the proximity effect, it comprises a data expansion means to create a bit expansion data including the proximity correction, the pattern data for performing the proximity correction, the proximity effect Supplement
Registered in advance as regular use bitmap data, and
The charged particle beam exposure apparatus is characterized in that it is adapted to the region of the beam. 2. A sample is preselected using a charged particle beam.
It is a charged particle beam exposure system that forms an exposure pattern.
And a charged particle beam generating means for generating a charged particle beam, and an optical path of the charged particle beam from the charged particle beam generating means.
Is disposed inside and shapes the cross-sectional shape of the charged particle beam.
Deflection an aperture and a beam passing through the aperture
A plurality of aperture-deflecting beam deflection means are arranged in a staggered pattern.
Blanking aperture array and exposure pattern data that has been bit expanded in advance,
Using proximity correction data to correct proximity effects
The calculated data and bit expansion data including proximity effect correction
A pattern for compensating the proximity effect of the exposure pattern , which comprises a data developing means for creating
Performs predetermined operations on data by adding bitmap data.
The bitmap data is calculated by subtraction or multiplication.
Data, addition, subtraction, or multiplication of the exposure pattern
Data as calculation information in the
The feature is that bit expansion is performed according to the calculation information.
A charged particle beam exposure apparatus. 3. The open beam deflecting means comprises the blur.
The first aperture provided for each aperture in the aperture array
A first electrode and a second electrode, and between the first and second electrodes
Aperture that passes through the corresponding aperture depending on the signal applied to
To control the arrival of the passing beam at the sample.
The charged particle beam exposure apparatus according to claim 1 or 2 . 4. The exposure pattern data is set in advance.
Cut out as a pattern area with a size smaller than
Bitmap data for exposure pattern cutout expressed in units
2. The device according to claim 1, characterized in that
Or the charged particle beam exposure apparatus of 2. 5. The exposure pattern cutout bitmap data is made to correspond to a plurality of pattern areas.
The charged particle beam exposure apparatus according to claim 4, wherein 6. A bit map for cutting out the exposure pattern
The bitmap data should be in the bitmap data registered in advance.
Read out and use any area.
5. The charged particle beam exposure apparatus according to claim 4 , wherein 7. Pattern data for performing the proximity effect correction
In advance as proximity effect correction bitmap data
The charged particle beam exposure apparatus according to claim 2 , wherein 8. The proximity effect correction bitmap data
Is made to correspond to multiple pattern areas.
The charged particle beam exposure apparatus according to claim 7 , which is characterized in that . 9. The proximity effect correction bitmap data
Is an arbitrary value in the bitmap data registered in advance.
Characterized by reading the area and using it
The charged particle beam exposure apparatus according to claim 1 or 7 . 10. Proximity effect correction of the exposure pattern is performed.
To perform a predetermined operation on the pattern data for
2. The charged particle beam exposure apparatus according to claim 1, wherein the addition, subtraction, or multiplication of the map data is performed. 11. Addition and subtraction of the bitmap data
Addition or multiplication to the data of the exposure pattern
As the calculation information, and according to the calculation information at the time of exposure.
2. A bit expansion is performed.
0 charged particle beam exposure apparatus. 12. An aperture for shaping the cross-sectional shape of a beam and
And a unit consisting of means for deflecting the beam associated with the aperture
Blanking apertures with multiple zigzag arrangements
-Beam beam is formed by irradiating array with particle beam
The round aperture further ahead inside the beam barrel
Whether or not it passes through the opening of the
Each opening is controlled by controlling the voltage applied to the deflection means.
Whether the beam formed by the hole reaches the sample or not
The exposure target is exposed by scanning while controlling
In the charged particle beam exposure system, the exposure pattern data
Data is decomposed on the device side as bit expansion data before exposure,
Charged particle beads that are stored in a storage device and are sequentially discharged and exposed
A method for processing exposure data of a system exposure apparatus, wherein the proximity component is corrected for the exposure pattern, and
Data for the pattern data of the area to be corrected.
And perform the predetermined operation to obtain the final bit expanded data.
The pattern data for the proximity effect correction,
Registered in advance as regular use bitmap data, and
A method for processing exposure data of a charged particle beam exposure apparatus, which is characterized in that the exposure data is made to correspond to a region . 13. An aperture for shaping the cross-sectional shape of the beam and
And a unit consisting of means for deflecting the beam associated with the aperture
Blanking apertures with multiple zigzag arrangements
-Beam beam is formed by irradiating array with particle beam
The round aperture further ahead inside the beam barrel
Whether or not it passes through the opening of the
Each opening is controlled by controlling the voltage applied to the deflection means.
Whether the beam formed by the hole reaches the sample or not
The exposure target is exposed by scanning while controlling
In the charged particle beam exposure system, the exposure pattern data
Data is decomposed on the device side as bit expansion data before exposure,
Charged particle beads that are stored in a storage device and are sequentially discharged and exposed
A method for processing exposure data of a system exposure apparatus, wherein the proximity component is corrected for the exposure pattern, and
Data for the pattern data of the area to be corrected.
And perform the predetermined operation to obtain the final bit expanded data.
In order to correct the proximity effect of the exposure pattern.
A predetermined operation on because of pattern data, bitmaps
Data addition, subtraction, or multiplication
Addition, subtraction, or multiplication of
To have as the calculation information in the data of the exposure pattern,
At the time of exposure, bit expansion is performed according to the calculation information.
An exposure data processing method for a charged particle beam exposure apparatus , characterized in that 14. The exposure pattern data is set in advance.
Cut out as a pattern area with a size smaller than
Bit map data for cutting out the exposure pattern
Claim to have as a data
12 or 13 is an exposure data processing method for a charged particle beam exposure apparatus. 15. A bitma for cutting out the exposure pattern
Data to correspond to multiple pattern areas
The exposure data processing method of the charged particle beam exposure apparatus according to claim 14 , wherein 16. A bitma for cutting out the exposure pattern
The bitmap data is the bitmap data registered in advance.
It is designed to read and use any area
15. The exposure data processing method for a charged particle beam exposure apparatus according to claim 14 , wherein. 17. A pattern data for performing the proximity effect correction.
In advance as bitmap data for proximity effect correction.
14. The exposure data processing method for a charged particle beam exposure apparatus according to claim 13 , wherein the exposure data is recorded . 18. The proximity effect correction bitmap data
Data to correspond to multiple pattern areas
18. The exposure data processing method of the charged particle beam exposure apparatus according to claim 17 . 19. The proximity effect correction bitmap data
Data is arbitrary in the bitmap data registered in advance
It is special that it is designed to read and use the area
18. The exposure data processing method for a charged particle beam exposure apparatus according to claim 12 or 17 . 20. Proximity effect correction of the exposure pattern is performed.
To perform a predetermined operation on the pattern data for
Map data can be added, subtracted, or multiplied
13. The charged particle beam according to claim 12, wherein
EXPOSURE data processing method for an exposure apparatus. 21. Addition and subtraction of the bitmap data
Addition or multiplication to the data of the exposure pattern
As the calculation information, and according to the calculation information at the time of exposure.
3. A bit expansion is performed.
An exposure data processing method for a charged particle beam exposure apparatus of 0.