JP3293854B2 - Charged particle beam exposure apparatus, its deflection data creation method, and charged particle beam exposure method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Contents] Industrial application field Conventional technology (FIG. 9) Problems to be solved by the invention Means for solving the problem (FIGS. 1 to 3) Action Embodiment (FIGS. 4 to 8) Effects of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charged particle beam exposure apparatus, a method for producing deflection data therefor, and a charged particle beam exposure method. The present invention relates to an apparatus for processing, a method of creating deflection data and an exposure method.

In recent years, fine pattern exposure has been performed by using a charged particle beam instead of photolithography, for example, by an electron beam or X-ray, in accordance with higher integration and higher density of a semiconductor integrated circuit (hereinafter referred to as LSI) device. It is shifting to pattern exposure.

According to the electron beam exposure apparatus,
In order to improve the processing efficiency, a semiconductor wafer is irradiated with a rectangular electron beam through a plurality of block patterns,
A block exposure method for performing exposure processing of various circuit patterns of SI has been developed.

However, the wiring pattern of the address decoder and the exclusive logic gate circuit of the memory cell is a repetitive pattern in which the contact hole installation position changes regularly. For this reason, it is necessary to provide a plurality of block patterns, such as a linear pattern or a linear pattern in which the formation positions of the rectangular portions change regularly, on the stencil mask (beam passing mask).

Further, when determining a deflection condition for returning the rectangular electron beam passing through the stencil mask to the optical axis, a certain position of each block mask pattern is determined on the sample with the mask taken out on the optical axis. It is determined based on the condition of projection at a certain fixed position.

For this reason, since there is no reference factor between the deflector for selecting a mask and the deflector for returning an optical axis, it is necessary to determine a return condition for each block mask pattern.
It takes a lot of time to create the deflection data.

Therefore, a reference factor is provided between the deflection data of the mask selecting deflector and the optical axis returning deflector, and the deflection efficiency is determined in a short time even when a plurality of such factors are provided. An exposure apparatus, a data creation method, and an exposure method capable of controlling the other remaining deflectors based on the deflection data of one deflector and performing high-resolution block exposure processing are desired. .

[0009]

2. Description of the Related Art FIG. 9 shows a configuration of a conventional electron beam exposure apparatus. In FIG. 9, an apparatus for exposing a semiconductor wafer 7 to a block pattern of an LSI using a rectangular electron beam 1a includes an electron source 1, a deflection driving circuit 2a, a rectangular shaping aperture 2b, a mask selecting deflector 2c, and an optical axis. Return deflector 2d, stencil mask 3,
It comprises a mask moving circuit 4, other deflectors 5 and an exposure control computer 6.

Note that the stencil mask 3 has a plurality of block mask patterns 3a as shown in the dashed circle in FIG.
.. 3d are provided with basic openings such as LSI wiring patterns and contact hole patterns.

The function of the exposure apparatus is that the electron beam emitted from the electron source 1 is shaped into a rectangular shaping aperture 2b.
To form a rectangular electron beam 1a, and the rectangular electron beam 1a is deflected by a mask selecting deflector 2c via a deflection driving circuit 2a.

By this deflection process, the stencil mask 3
Is selected, for example, a rectangular block pattern 3a. The rectangular electron beam 1a passing through the block mask pattern 3a is returned to the optical axis by the optical axis return deflector 2d.
a is deflected and scanned on the semiconductor wafer 7 by another deflector 5.

Thus, the wafer 7 is exposed to a contact hole pattern or the like of an LSI. Thereafter, the stage is moved to change the exposure area of the semiconductor wafer 7.

[0014]

According to the prior art, the rectangular electron beam 1 that has passed through the stencil mask 3 is used.
When obtaining a deflection condition for returning a to the optical axis (hereinafter simply referred to as a return condition), a state in which the stencil mask 3 is incorporated in the optical axis of the electron beam (hereinafter referred to as a load state).
Thus, a certain position of each block mask pattern is determined from the condition of being projected onto a certain position on the sample.

For this reason, since there is no reference (common) factor between the mask selecting deflector 2c and the optical axis returning deflector 2d, it is necessary to determine the rewinding condition for each of the block mask patterns 3a to 3d. However, the following problem arises.

If the number of block mask patterns 3a to 3d formed on the stencil mask 3 is increased to several tens of units due to an exposure request for a feature pattern of the LSI to be designed, deflection satisfying the swing-back condition of the optical axis return deflector 2d is achieved. Data D
2 takes a lot of time to create. As a result, depending on the arrangement of the mask pattern, there is a case where the conditions for the reversion are not accurately determined in a short time.

Further, the block mask patterns 3 a to 3
In order to improve the selection accuracy of 3d, a mask selecting deflector 2c for selecting the block mask patterns 3a to 3d.
Optical axis return deflector 2 for returning a rectangular electron beam 1a to the optical axis
When the number of mounting steps of d increases, it takes a lot of time to create the individual deflection data D11 and D12 satisfying the mask selection condition and the swing-back condition of the deflectors 2c and 2d.

As a result, when another block mask pattern of the stencil mask 3 is selected, it is difficult to pass the rectangular electron beam 1a through the same path as the previous path, and the optical axis of the rectangular electron beam 1a is accurately returned to the optical axis. Hinders

Further, as the number of mounting stages of the mask selecting deflector 2c and the optical axis returning deflector 2d increases, the individual deflection data D11 and D12 satisfying the mask selecting condition and the returning condition of the rectangular electron beam 1a are generated. The burden on the managing CPU (Central Processing Unit) increases. In addition, every time the stencil mask 3 is displaced from the optical axis, correction processing of the deflection data is forced each time, and the control load on the CPU increases.

For example, the CPU must always manage the mask formation positions such as the block mask patterns 3a to 3d and the deflection amount for mask selection and the deflection amount for optical axis return for deflecting the rectangular electron beam 1a there.

For this reason, it is difficult to perform a desired beam adjustment, which hinders high-resolution block exposure processing. The present invention has been made in view of the problems of the conventional example described above, and the deflection data of the mask selecting deflector and the optical axis return deflector are determined without individually determining the return condition, and the data is interposed therebetween. Providing a reference factor, even when a plurality of them are provided, determining the deflection efficiency in a short time, controlling the other remaining deflectors based on the deflection data of one deflector, It is another object of the present invention to provide a charged particle beam exposure apparatus capable of performing a high-resolution block exposure process, a deflection data creation method thereof, and a charged particle beam exposure method.

[0022]

FIG. 1 is a diagram showing the principle of a charged particle beam exposure apparatus according to the present invention.
FIG. 3C is a principle view of a method for creating deflection data of the charged particle beam exposure apparatus according to the present invention, and FIGS. 3A and 3B.
1 shows a principle diagram of a charged particle beam exposure method according to the present invention.

FIG. 1 shows a charged particle beam exposure apparatus according to the present invention.
As shown in FIG. 2 and based on the charged particle source 11 for generating the charged particle beam 11A and the deflection data Da, the charged particle beam 11A is divided into a plurality of block mask patterns BPi, (i = 1, 2,... I ), A beam deflecting means 13 comprising the plurality of block mask patterns BPi and shaping the pattern of the charged particle beam 11A, and associating with the deflection data Da. Second deflection means 14A, 14B comprising two or more deflectors for returning the pattern-shaped charged particle beam 11A to the optical axis based on the obtained other deflection data Dc, Dd.
And at least the input and output of the charged particle generation source 11 and the beam shaping means 13 are controlled, and the deflection data Da and the other deflection data Dc and Dd are respectively transmitted to the first deflection means 12 and the Second deflection means 14A, 14
B, and control means 15 for supplying both the first deflecting means 12 and the second deflecting means 14A, 14B based on the deflection data Da. It is characterized by the following.

In the charged particle beam exposure apparatus, the first deflecting means 12 comprises one or more deflectors provided in a region above the beam shaping means 13.

Further, in the charged particle beam exposure apparatus, in addition to the beam shaping means 13, another shaping means 16 for shaping the charged particle beam 11A is provided.

Further, in the charged particle beam exposure apparatus, another deflecting means 17 for deflecting the charged particle beam 11A is provided in addition to the first and second deflecting means 12, 14A and 14B. And

[0027] The deflection data creating method of the charged particle beam exposure apparatus of the present invention is a method of creating beam deflection data DX and DY of the charged particle beam exposure apparatus.
As shown in FIGS. 2A and 2B, under non-use conditions where the first and second deflecting means 12, 14A and 14B are not used, and the first and second deflecting means 12, 14A and 14B. In this method, the beam deflection data DX and DY are created based on the use condition of the beam deflection data DX.

In the method for creating deflection data of the charged particle beam exposure apparatus, the beam deflection data DX,
As shown in the flow chart of FIG. 2C, the DY creation processing is performed in step P1 at the first and second deflecting means 1.
Under the non-use conditions of 2, 14A and 14B, the charged particle beam 11 shaped in the area above the first deflecting means 12
A cross-sectional image EP of A is projected on the sample surface, and thereafter, step P
Under the use conditions of the first and second deflecting means 12, 14A, 14B in 2, the first and second deflecting means 12, 14A,
An arbitrary deflection data Da is supplied to one of the deflecting means in 14B, and then, in step P3, the sectional image EP of the charged particle beam 11A projected on the sample surface based on the supply of the deflection data Da and the first , The second deflecting means 12, 14A, 14
B is superimposed with the cross-sectional image EP of the charged particle beam 11A under the non-use condition of B, and then, in Step P4, other deflectors 12B, 14A, and 14B other than the one deflecting means 12A based on the superposition. Deflection data Db, Dc, D
It is characterized in that d is determined.

Further, in the method for creating deflection data of the charged particle beam exposure apparatus, as shown in FIG. 2C, the beam shaping means 13 is removed from the optical axis C of the charged particle beam 11A. It is characterized in that the beam deflection data DX and DY are created and processed based on the state in which the beam shaping means 13 is taken into the optical axis C of the charged particle beam 11A.

Further, according to the charged particle beam exposure method of the present invention, as shown in the flowchart of FIG. 3, first, in step P1, a plurality of block mask patterns BPi, i = 1, 2 based on the beam deflection data DX, DY. .. Perform a first deflection process for deflecting the charged particle beam 11A to one of the i, and then perform a pattern shaping process for the charged particle beam 11A based on the first deflection process in step P2. In P3, a second deflection process for returning the charged particle beam 11A, which has been pattern-shaped based on the deflection data Dc and Dd based on the beam deflection data DX and DY, to the optical axis is performed.

In the charged particle beam exposure method, as shown in the flow chart of FIG. 3, after the second deflection process, in step P4, based on another deflection process of the charged particle beam 11A, the object 18 to be exposed is exposed. The above-mentioned object is achieved by performing a pattern exposure process.

[0032]

[Operation] According to the charged particle beam exposure apparatus of the present invention,
As shown in FIG. 1, a charged particle generation source 11, a first deflecting unit 12, a beam shaping unit 13, a second deflecting unit 14, and a control unit 15 are provided. The other deflecting means 14 are deflected and output controlled based on the beam deflection data DX and DY.

For example, when the charged particle beam 11A is generated by the charged particle generation source 11, the charged particle beam 11A is shaped into a rectangular shape by other shaping means 16. In addition, the charged particle beam 11A shaped into a rectangular shape receives a plurality of block mask patterns BPi, [i
= 1,... I] via the first deflecting means 12. At this time, the charged particle beam 11A is deflected by one or more first deflecting means 12 provided in an area above the beam shaping means 13.

As a result, when the charged particle beam 11A passes through the beam shaping means 13 and is patterned, the charged particle beam 11A is controlled by the control means 15.
Is returned to the optical axis by the second deflecting means 14 via

At this time, the charged particle beam 11A is deflected by one or more second deflecting means 14 provided below the beam shaping means 13. Here, the control unit 15 controls the deflection output of the second deflection unit 14 based on, for example, one beam deflection data Da based on the first deflection unit 12.

The charged particle beam 11A returned to the optical axis
Is deflected by the other deflecting means 17 and the exposure target 1 is
At 8 a block exposure process is performed. For this reason, even when the number of mounting steps of the first deflecting means 12 for selecting the block mask patterns BP1 to BPi and the second deflecting means 14 for returning the charged particle beam 11A to the optical axis C is increased, the control means 15 It is possible to perform deflection output control in a hardware manner without imposing a burden on the user.

Thus, the first and second deflecting means 12,
Since the number of mounting steps 14 can be increased, the selection accuracy of the block mask patterns BP1 to BPi can be improved. In addition, when a displacement between the beam shaping means 13 and the optical axis occurs, the beam deflection data DX, D
Correction processing of the deflection data Da to Dd can be performed based on Y, and the control load on the control unit 15 is reduced.

For example, the control means 15 does not need to always manage the mask formation positions such as the block mask patterns BP1 to BPi, the mask selection deflection amount for deflecting the charged particle beam 11A there, and the optical axis return deflection amount. .

According to the method for creating deflection data of the charged particle beam exposure apparatus of the present invention, as shown in FIGS. 2A and 2B, the first and second deflecting means 12 and 14 are not used. Under non-use conditions and the first and second deflecting means 12, 14
Beam deflection data D based on use conditions using
X and DY are created.

For example, as shown in the flowchart of FIG. 2C, in step P1, under these non-use conditions, and the beam shaping means 13 controls the optical axis C of the charged particle beam 11A.
In a state where the charged particle beam 11A is detached from the sample, a cross-sectional image EP of the charged particle beam 11A is projected onto the sample surface. Is supplied. Then, in step P3, the sectional image EP of the charged particle beam 11A projected on the sample surface based on the supply of the deflection data Da and the non-use of the first and second deflecting means 12 and 14. The cross-sectional image EP of the charged particle beam 11A under the conditions is superimposed.

Therefore, in step P4, the deflection data Db, Dc, and Dd of the deflectors 12B, 14A, and 14B other than the one deflecting means 12A are calculated based on the superposition of the two cross-sectional images EP, thereby obtaining the beam. In a state where the shaping means 13 is taken in the optical axis C of the charged particle beam 11A, the deflection based on the mask deflection conditions and the swingback conditions of the respective block mask patterns BP1 to BPi are set using the beam deflection data DX and DY as reference factors. Data Da to Dd and the like can be created.

Thus, even if another block mask pattern of the beam shaping means 13 is selected, the charged particle beam 11A is determined based on the beam deflection data DX and DY.
Is deflected, it is easy to pass the charged particle beam 11A through the same path as the previous path, and it is possible to accurately return it to the optical axis.

Even when the number of mounting steps of the first deflecting means 12 and the second deflecting means 14 is increased, individual deflecting which satisfies the mask selection condition and the rewinding condition of the deflecting means 12 and 14 is performed. The efficiency can be determined in a short time, and the deflection data Da to Dd can be created in a short time.

Further, according to the charged particle beam exposure method of the present invention, as shown in the flowchart of FIG.
Step P2 is performed based on the first deflection processing in step P1.
Performs the pattern shaping process of the charged particle beam 11A, and then returns the charged particle beam 11A, which has been pattern-shaped based on the other deflection data Dc and Dd associated with the beam deflection data Da, to the optical axis C in step P3. The second deflection process is performed.

For this reason, in step P4 of the flowchart of FIG. 3B, it is possible to perform a high-resolution pattern exposure process on the object 18 based on another deflection process of the charged particle beam 11A. With this, 64 mega DRAM
It becomes possible to perform a block exposure process for an ultrafine pattern or the like.

Thus, it is possible to provide a highly reliable and high performance block pattern selective transfer type electron beam exposure apparatus.

[0047]

Next, an embodiment of the present invention will be described with reference to the drawings. 4 to 8 are diagrams illustrating a charged particle beam exposure apparatus according to an embodiment of the present invention, a method for creating deflection data thereof, and a charged particle beam exposure method. FIG.
1 shows a configuration diagram of an electron beam exposure apparatus according to an embodiment of the present invention.

For example, an electron beam exposure apparatus for performing a block exposure process on a semiconductor wafer 28 includes an electron gun 21, first and second mask selecting deflectors 22A and 22B in FIG.
Signal amplifiers (hereinafter referred to as AMP / DAC) 221, 222, stencil mask 23, mask stage controller 23A,
First and second optical axis return deflectors 24A, 24B, AMP / DAC
241, 242, aperture 26A, first and second electronic lenses
26B, 26C, an electromagnetic deflector 27A, an electrostatic deflector 27B, a blanker 27C, and an exposure controller 25.

That is, the electron gun 21 is connected to the charged particle source 1
1 is an embodiment for generating an electron beam as an example of the charged particle beam 11A. The first and second mask selecting deflectors 22A and 22B, and the AMP / DACs 221 and 222
The first mask selecting deflector 22A roughly deflects the rectangular electron beam 21A based on the first deflection signal S1. Also, the second
The mask selecting deflector 22B is a rectangular electron beam deflected by the preceding deflector 22A based on the second deflection signal S2.
21A is a plurality of block mask patterns BPi, [i = 1, 2] on the stencil mask as shown in the dashed ellipse in FIG.
2 ... i].

The AMP / DAC 221 converts the first deflection data Da from digital to analog and converts the first deflection signal Da into a first deflection signal S.
1 to the deflector 22A.
Numeral 2 is for converting the second deflection data Db from digital to analog and outputting a second deflection signal S2 to the deflector 22B.

The stencil mask 23 and the mask stage controller 23A are one embodiment of the beam shaping means 13, and the stencil mask 23 is composed of a plurality of block mask patterns BPi (see the broken line ellipse in FIG. 1). Also,
The mask 23 shapes the pattern of the rectangular electron beam 21A.

Note that the first and second mask selecting deflectors 22A, 22A,
22B is provided, and first and second optical axis return deflectors 24A and 24B are provided below the area.

The first and second optical axis return deflectors 24A, 24A
B, AMP / DAC 241 and 242 are an embodiment of the second deflecting means 14, and the first optical axis return deflector 24A is a rectangular electron beam pattern-shaped based on the third deflection signal S3.
21A is roughly returned to the optical axis. The second optical axis return deflector 24B slightly returns the rectangular electron beam 21A deflected by the previous deflector 24A to the optical axis based on the fourth deflection signal S4.

The AMP / DAC 241 performs digital / analog conversion of the third deflection data Dc to convert the third deflection data Dc into a third deflection signal Sc.
3 to the deflector 24A.
Numeral 2 is for converting the fourth deflection data Dd from digital to analog and outputting a fourth deflection signal S4 to the deflector 24B.

The aperture 26A and the first and second electron lenses 26B and 26C are another embodiment of the shaping means 16. The aperture 26A converts the electron beam 11A generated from the electron gun 21 into a rectangular section. Shape and its rectangular electron beam
21A is emitted in the direction of the first mask selecting deflector 22A.

The first electron lens 26B is for positioning the focal point of the rectangular electron beam 21A deflected by the second mask selecting deflector 22B, and the second mask selecting deflector 22B and the stencil mask 23 are used. And provided between them.
The second electron lens 26C passes through the block mask pattern BPi and is shaped into a rectangular electron beam 21A.
And is provided between the stencil mask 23 and the first optical axis return deflector 24A.

Further, the electromagnetic deflector 27A, the electrostatic deflector 27
B, the blanker 27C is an embodiment of the other deflecting means 17, and the electromagnetic deflector 27A deflects the pattern-shaped rectangular electron beam 21A largely (main deflection). Also,
The electrostatic deflector 27B deflects the light slightly (sub-deflection). The blanker 27C controls the irradiation of the rectangular electron beam 21A.

The exposure control device 25 is an embodiment of the control means 15 and includes a blanking control unit 51 and a pattern control unit 5.
2, a deflection drive control unit 53, a sequence control unit 54, an interface unit 55, a memory unit 56, and a CPU 57. The function of the exposure control device 25 is as follows.
It controls the input / output of AMP / DACs 221 and 222, AMP / DACs 241 and 242, mask stage controller 23A, electromagnetic deflector 27A, electrostatic deflector 27B and blanker 27C.

For example, the pattern controller 52 controls the beam deflection data D based on the first mask selecting deflector 22A.
The deflection output of the second mask selecting deflector 22B and the first and second optical axis returning deflectors 24A and 24B is controlled based on X and DY. The method of creating the first to fourth deflection data Da to Dd will be described in detail with reference to FIGS.

As described above, according to the electron beam exposure apparatus according to the embodiment of the present invention, as shown in FIG.
1, first and second mask selecting deflectors 22A, 22B, AMP
/ DAC 221, 222, stencil mask 23, mask stage controller 23A, first and second optical axis return deflectors
24A, 24B, AMP / DAC241, 242, aperture 26A,
First and second electronic lenses 26B and 26C, electromagnetic deflector 27A,
Electrostatic deflector 27B, blanker 27C and exposure controller 25
The second mask selecting deflector 22B, the first and second optical axis return based on the beam deflection data DX and DY based on the first mask selecting deflector 22A by the controller 25. The deflectors 24A and 24B are subjected to deflection output control.

For example, when the electron beam 11A is generated by the electron gun 21, the electron beam 11A is shaped into a rectangular shape by the aperture 26A. Further, the rectangular electron beam 21A shaped into a rectangular shape is supplied to the plurality of block mask patterns BPi, [i
= 1,... I] by the first and second mask selecting deflectors 22A and 22B (see FIG. 8).

At this time, two first and second mask selecting deflectors provided in an area above the stencil mask 23 are used.
The rectangular electron beam 21A is deflected by 22A and 22B based on the first and second deflection data Da and Db.

Thus, when the rectangular electron beam 21A passes through one block mask pattern BPi of the stencil mask 23 and is shaped,
The pattern-shaped rectangular electron beam 21A is transmitted via the control device 25 to the first and second optical axis return deflectors 24A and 24A.
B returns to the optical axis.

At this time, the rectangular electron beam 21A is formed by two first and second optical axis return deflectors 24A and 24B provided below the stencil mask 23 and provided with the blanker 27C interposed therebetween. Be deflected. Here, the pattern control unit 52 of the exposure control device 25 uses, for example, the second mask selecting deflector 22B, the first mask deflector 22B based on the beam deflection data Da based on the first mask selecting deflector 22A.
The second optical axis return deflectors 24A and 24B are subjected to deflection output control.

The rectangular electron beam 21A returned to the optical axis
Is deflected by an electromagnetic deflector 27A or an electrostatic deflector 27B, and a block exposure process is performed on a semiconductor wafer 28 which is an example of the subject 18 to be exposed.

For this reason, the block mask patterns BP1 to
First and second mask selecting deflectors 22A for selecting BPi,
Even when the number of mounting stages of the first and second optical axis return deflectors 24A and 24B for returning the charged particle beam 11A to the optical axis is increased, the pattern control unit 52 and the CPU 56 of the exposure control device 25 are not required. Deflection output control can be performed by hardware without imposing a burden.

Thus, the first and second mask selecting deflectors 22A and 22B and the first and second optical axis returning deflectors 24A and 24A are provided.
Since the number of mounting steps of the 24B can be increased as required, it is possible to improve the selection accuracy of the block mask patterns BP1 to BPi. Further, when a positional shift between the stencil mask 23 and the optical axis occurs, correction processing of the deflection data Da to Dd can be performed based on the beam deflection data DX and DY. Decrease.

For example, the pattern control unit 52 and the CPU 56 of the exposure control unit 25 operate as the block mask patterns BP1 to BP
It is not necessary to always manage the mask formation position such as Pi and the deflection amount for mask selection and the deflection amount for optical axis return for deflecting the rectangular electron beam 21A there.

Next, a description will be given of a deflection data creation method according to an embodiment of the present invention. FIG. 5 is a flowchart illustrating the creation of deflection data according to the embodiment of the present invention.
(A), (b) has shown the supplementary explanatory drawing.

For example, when the deflection data Da to Dd of the electron beam exposure apparatus according to the embodiment of the present invention is created, the first and second mask selecting deflectors 22A and 22B and the first and second mask selecting deflectors 22A and 22B are used. As the reference factors for the beam deflection data DX and DY of the optical axis return deflectors 24A and 24B, let X and Y be the deflection amounts of the electron beam 21A deflected to a certain block mask pattern BPi.

In FIG. 5, first, in step P1, the stencil mask 23 is removed from the optical axis C of the electron beam 11A (see FIG. 6A). At this time, the stencil mask 2 is controlled by the mask stage controller 23A.
3 is moved from the optical axis C of the electron beam 11A.

Next, in step P2, under the condition that the first and second mask deflectors 22A and 22B and the first and second optical axis return deflectors 24A and 24B are not used, the aperture 26A is used.
The cross-sectional image EP of the rectangular electron beam 21A shaped by the above is projected onto the sample surface.

Thereafter, in step P3, under the conditions of use of the first and second mask selecting deflectors 22A and 22B and the first and second optical axis returning deflectors 24A and 24B, for example, the first mask A process of supplying arbitrary deflection data Da to the selection deflector 22A is performed.

Next, in step P4, the rectangular electron beam projected on the sample surface based on the supply processing of the deflection data Da
21A cross-sectional image EP and first and second mask selecting deflectors 22
A, 22B and the cross-sectional image EP of the rectangular electron beam 21A under the non-use conditions of the first and second optical axis return deflectors 24A, 24B.
Is superimposed.

Further, in step P5, the deflection data D of the second mask selecting deflector 22B and the first and second optical axis returning deflectors 24A and 24B are obtained based on the superposition processing of the two sectional images.
b, Dc, and Dd are calculated.

At this time, for example, the first and second
When the deflection data Da to Dd of the mask selecting deflectors 22A and 22B and the first and second optical axis return deflectors 24A and 24B are replaced with X and Y components, respectively, the correction calculation formula is as follows. Become.

First, the deflection data Da of the first mask selecting deflector 22A is converted to first mask differential deflection data BSX1, BSX.
Assuming that SY1, BSX1 = G1 × XCOS θ1 + G1 × YSIN θ1 BSY1 = −G1 × XSIN θ1 + G1 × YCOS θ1

Further, the deflection data Db of the second mask selecting deflector 22B is converted to the second mask differential deflection data BSX2, BSX.
Assuming that SX2, BSX2 = -G2 * XCOS [theta] 2-G2 * YSIN [theta] 2 BSX2 = G2 * XSIN [theta] 2-G2 * YCOS [theta] 2.

Further, the deflection data Dc of the first optical axis return deflector 24A is converted to third mask differential deflection data BSX3, BSX.
Assuming that SY3, BSX3 = -G3.times.XCOS .theta.3 + G3.times.YSIN .theta.3 BSY3 = -G3.times.XSIN .theta.3-G3.times.YCOS .theta.3.

The deflection data Dd of the second optical axis return deflector 24B is converted into fourth mask differential deflection data BSX4 and BSY.
Assuming that 4, BSX4 = G4.times.XCOS .theta.4-G4.times.YSIN .theta.4 BSY4 = G4.times.XSIN .theta.4 + G4.times.YCOS .theta.4. Here, (X, Y) corresponds to the deflection amount of the rectangular electron beam 21A on the block mask pattern surface, and
G4 indicates a gain, and θ1 to θ4 indicate phase differences.

The first and second mask selecting deflectors 22
A, 22B and first and second optical axis return deflectors 24A, 24B are symmetrically arranged with respect to the stencil mask 23 via first and second electron lenses 26B, 26C. For example, in determining the mask selection deflection condition and the return deflection condition of the electron beam 21A, the gains G1 to G4 and the phase difference θ are determined.
1 to θ4 can be approximately assumed to be G1 ≒ G4, G2 ≒ G3, θ1 ≒ θ4, θ2 ≒ θ3, and the condition search can be simplified.

For example, the condition search is performed as follows. First, with respect to the gain G1, the phase difference θ2, and the deflection amount X, the values of G1 (= G4), θ2 (= θ3), and X (= Y) are set as parameters (fix). (= G3), θ1 (= θ4),
Find the maximum condition of the deflection current value.

Further, for the gain G1 and the phase difference θ1, the value of X (= Y) is determined based on the values obtained above for G1 (= G4) and θ1 (= θ4), and the gain G2 and the phase difference θ2 are determined. , G2 (= G3) and θ2 (= θ3). This is the maximum condition of the deflection current value. As a result, an approximate value of the coefficient of the correction calculation formula is obtained from.

Thereafter, in step P6, beam deflection data DX and DY are created based on the state in which the stencil mask 23 is taken in the optical axis C of the electron beam 11A (see FIG. 6B). Individual coefficients (gains G1 to G4
, Etc.) to select the block mask pattern BPi with the maximum current value. Thus, no matter what block mask pattern BPi is selected, the block mask pattern BPi is returned to the same position on the sample surface.

As described above, according to the deflection data creating method of the electron beam exposure apparatus according to the embodiment of the present invention, FIG.
As shown in (a) and (b), the first and second mask selecting deflectors 22A and 22B and the first and second optical axis returning deflectors 24 are provided.
The beam deflection data DX and DY are created based on the non-use condition in which A and 24B are not used and the use condition in which the four deflectors 22A and 22B and 24A and 24B are used.

For example, as shown in the flow chart of FIG. 4, the cross section of the rectangular electron beam 21A under the non-use condition and the stencil mask 23 removed from the optical axis C of the electron beam 11A in Step P2. The image EP is projected onto the sample surface, and then, in step P3, under these conditions of use, any deflection data Da is supplied to the first mask selecting deflector 22A, and then step P4
A cross-sectional image EP of the rectangular electron beam 21A projected on the sample surface based on the supply of the deflection data Da and the four deflectors 22
A cross-sectional image EP of the rectangular electron beam 21A under non-use conditions of A, 22B and 24A, 24B is superimposed.

For this reason, in step P5, the four deflectors 22A, 22B and 24 based on the superposition of the two sectional images EP.
A, 24B, first through fourth mask differential deflection data BSX
1, BSY1, BSX2, BSY2, BSX3, BSY3 and BSX
4 and BSY4, the deflection amounts (maximum conditions of the deflection current value) X and Y of the rectangular electron beam 21A are set as reference factors in a state where the stencil mask 23 is taken in the optical axis C of the electron beam 11A in step P6. As a result, it is possible to create the mask deflection conditions relating to the respective mask patterns BP1 to BPi, the deflection data Da to Dd relating to the reversion conditions thereof, and the like.

Thus, when another block mask pattern of the stencil mask 23 is selected, the rectangular electron beam 21A is deflected based on the beam deflection data DX and DY, so that the rectangular electron beam 21A follows the same path as the previous path. It is easy to pass the beam 21A, and it is possible to accurately return it to the optical axis.

The first and second mask selecting deflectors 22
Even if the number of mounting stages of the deflectors A, 22B and the first and second optical axis return deflectors 24A, 24B is increased, the mask selection conditions and the rewinding of the four deflectors 22A, 22B, 24A, 24B are required. The individual deflection efficiencies satisfying the conditions can be determined in a short time, and the deflection data Da to Dd can be created in a short time.

Next, an electron beam exposure method according to an embodiment of the present invention will be described while supplementing the operation of the exposure apparatus. FIG. 7 is a processing flowchart of electron beam exposure according to the embodiment of the present invention, and FIG. 8 is a supplementary explanatory diagram thereof.

For example, as shown in FIG.
7, when the block pattern exposure process is performed, first in FIG.
A plurality of block mask patterns BPi, [i
= 1, 2,... I] (first deflection process).

At this time, the electron beam 11A generated from the electron gun 21 is changed by the aperture 26A into the rectangular electron beam 21A.
The rectangular electron beam 21A is emitted to the first mask selecting deflector 22A. Also, the exposure control device 25
The first and second deflection data Da and Db are output to the AMP / DACs 221 and 222 via the pattern controller 52 (see FIG. 4).

For example, the pattern controller 52 controls the beam deflection data D based on the first mask selecting deflector 22A.
The deflection output of the second mask selecting deflector 22B and the first and second optical axis returning deflectors 24A and 24B is controlled based on X and DY.

As a result, the AMP / DACs 221 and 222 convert the first and second deflection data Da and Db from digital to analog, and convert the first and second deflection signals S1 and S2 into the two deflectors 22A and 22B. Is output to

Further, based on the first deflection signal S1, the rectangular electron beam 21 is deflected by the first mask selecting deflector 22A.
A is coarsely deflected. Further, the rectangular electron beam 21A deflected by the deflector 22A by the second mask selecting deflector 22B based on the second deflection signal S2 is converted into a plurality of block mask patterns BPi,
[I = 1, 2,... I] (see FIG. 8).

Next, in step P2, a pattern shaping process of the rectangular electron beam 21A is performed based on the first deflection process.
At this time, a rectangular electron beam is formed by the first electron lens 26B.
The 21A focus is aligned. The rectangular electron beam 21A passes through one block mask pattern BPi of the stencil mask 23 to be shaped. A rectangular electron beam that has been shaped by passing through the block mask pattern BPi by the second electron lens 26C.
21A is imaged.

Further, in step P3, the rectangular electron beam 21A, which has been pattern-shaped based on the deflection data Dc and Dd based on the beam deflection data DX and DY, is returned to the optical axis C (second deflection processing). .

At this time, the third and fourth deflection data Dc and Dd are transmitted via the pattern control section 52 of the exposure control device 25.
Is output to the AMP / DACs 241 and 242, the AMP / DAC
The 241 and 242 convert the third and fourth deflection data Dc and Dd from digital to analog, and output the third and fourth deflection signals S3 and S4 to the deflectors 24A and 24B.

Thus, the rectangular electron beam 21A whose pattern is shaped by the first optical axis return deflector 24A based on the third deflection signal S3 is roughly returned to the optical axis. Further, the rectangular electron beam 21A deflected by the previous deflector 24A by the second optical axis return deflector 24B based on the fourth deflection signal S4 is finely returned to the optical axis.

Thereafter, in step P4, the rectangular electron beam 21
A block pattern exposure process is performed on the semiconductor wafer 28 based on the electromagnetic deflection process or the electrostatic deflection process A. At this time, the electromagnetic deflector 27A and the electrostatic deflector 27B are controlled via the deflection drive control unit 53 and the sequence control unit 54 of the exposure control device 25.

For example, the pattern-shaped rectangular electron beam 21A is largely deflected (mainly deflected) by the electromagnetic deflector 27A. Further, it is slightly deflected (sub-deflected) by the electrostatic deflector 27B. The irradiation of the rectangular electron beam 21A is controlled by the blanker 27C via the blanking controller 51 of the exposure controller 25.

Therefore, by connecting the basic pattern drawn by irradiating the semiconductor wafer 28 with one shot of the rectangular electron beam 21A, a repetitive continuous pattern such as a memory cell of a DRAM can be exposed.

Thereafter, in step P5, it is determined whether the exposure processing is completed. At this time, if the exposure processing is not completed (N
O) returns to step P1 and returns to steps P1 to P4.
To continue. Exposure control is terminated by the end of the exposure processing (YES).

As described above, according to the electron beam exposure method according to the embodiment of the present invention, as shown in the flowchart of FIG. 7, based on the first deflection processing in step P1, the rectangular electron beam 21A is used in step P2. , And then, in step P3, the beam deflection data DX, D
A second method for returning the rectangular electron beam 21A, which has been pattern-shaped based on the deflection data Dc and Dd based on Y, to the optical axis.
Deflecting process.

For this reason, at step P4 in the flowchart of FIG. 7, an ultrafine pattern such as a 64 mega DRAM is formed on the semiconductor wafer 28 based on the electromagnetic deflection process or the electrostatic deflection process of the rectangular electron beam 21A with a constant throughput and Exposure processing can be performed with high resolution.

As a result, it is possible to provide a highly reliable and high performance block pattern selective transfer type electron beam exposure apparatus.

[0107]

As described above, according to the charged particle beam exposure apparatus of the present invention, the charged particle generation source, the first and second charged particle sources,
Deflection means, beam shaping means and control means,
The control means controls the deflection output of the other deflection means based on the beam deflection data based on the one deflection means.

Therefore, even when the number of mounting steps of the first deflecting means for selecting the block mask pattern provided in the beam shaping means and the second deflecting means for returning the charged particle beam to the optical axis is increased, Deflection output control can be performed by hardware without imposing a burden on the control means. This makes it possible to improve the selection accuracy of the block mask pattern.

Further, according to the deflection data creating method of the charged particle beam exposure apparatus of the present invention, based on the non-use condition in which the first and second deflecting means are not used and the use condition in which the deflecting means is used. The beam deflection data is created.

For this reason, the deflection data of the deflecting means is determined based on the superposition processing of the cross-sectional image of the charged particle beam under the non-use condition and the cross-sectional image of the charged particle beam under the use condition. This makes it possible to determine the mask deflection conditions for the respective block mask patterns and the deflection efficiencies for the return conditions thereof in a short time, using the beam deflection data as a reference factor.

Even when another block mask pattern of the beam shaping means is selected, the charged particle beam is deflected on the basis of the beam deflection data, so that the charged particle beam travels on the same path as the previous path. It is easy to pass the beam, and the charged particle beam can be accurately returned to the optical axis.

Further, according to the charged particle beam exposure method of the present invention, the charged particle beam is shaped into a pattern based on a deflection process for deflecting the charged particle beam into one of the block mask patterns. Deflection processing is performed to return the charged particle beam, which has been pattern-shaped based on the deflection data based on the data, to the optical axis.

Therefore, by subjecting the patterned particle beam to deflection processing by another deflector, it becomes possible to perform high-resolution pattern exposure processing on the object to be exposed. This makes it possible to perform a block exposure process for an ultra-fine pattern or the like of a 64 mega DRAM or the like.

This greatly contributes to providing a highly reliable and high performance block pattern selective transfer type electron beam exposure apparatus.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a charged particle beam exposure apparatus according to the present invention.

FIG. 2 is a principle diagram of a method for creating beam deflection data of the charged particle beam exposure apparatus according to the present invention.

FIG. 3 is a principle diagram of a charged particle beam exposure method according to the present invention.

FIG. 4 is a configuration diagram of an electron beam exposure apparatus according to an embodiment of the present invention.

FIG. 5 is a flowchart of creating beam deflection data according to the embodiment of the present invention.

FIG. 6 is a supplementary explanatory diagram of a data creation flowchart according to the embodiment of the present invention.

FIG. 7 is a processing flowchart of electron beam exposure according to the embodiment of the present invention.

FIG. 8 is a supplementary explanatory diagram of the exposure processing flowchart according to the embodiment of the present invention.

FIG. 9 is a configuration diagram of an electron beam exposure apparatus according to a conventional example.

[Explanation of symbols]

11: charged particle generation source, 12, 12A, 12B or 14, 14A, 14B: first or second deflecting means, 13: beam shaping means, 15: control means, 16: other shaping means, 17: other Deflection means, 11A: charged particle beam, Da to Dd: deflection data, DX, DY: beam deflection data, C: optical axis, BPi [i = 1, 2, i]: block mask pattern, EP: cross-sectional image.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/027 G03F 7/20

Claims (9)

(57) [Claims] 1. A charged particle source (11) for generating a charged particle beam (11A) and a plurality of block mask patterns (BPi, [i) based on deflection data (Da).
= 1, 2,... I)).
2) and the plurality of block mask patterns (BPi),
The beam shaping means (13) for shaping the pattern of the charged particle beam (11A), and the pattern shaping based on another deflection data (Dc, Dd) associated with the deflection data (Da). Second deflecting means (14A, 14B) comprising two or more deflectors for returning the charged particle beam (11A) to the optical axis; at least the charged particle generation source (11) and the beam shaping means (13) And the deflection data (Da) and the other deflection data (Dc, Dd).
(15) supplying the first and second deflecting means (12) and (14A, 14B) respectively to the first deflecting means (12) and the second deflecting means (14A, 14B).
Wherein the control means (15) controls both the first deflecting means (12) and the second deflecting means (14A, 14B) based on the deflection data (Da). A charged particle beam exposure apparatus characterized in that: 2. A charged particle beam exposure apparatus according to claim 1, wherein said first deflecting means comprises at least one deflector provided in an area above the beam shaping means. Charged particle beam exposure apparatus. 3. A charged particle beam exposure apparatus according to claim 1, wherein said beam shaping means further includes a shaping means for shaping said charged particle beam.
6) A charged particle beam exposure apparatus provided with: 4. A charged particle beam exposure apparatus according to claim 1, wherein said first and second deflection means (12, 14A, 14A).
A charged particle beam exposure apparatus characterized in that, in addition to B), another deflecting means (17) for deflecting the charged particle beam (11A) is provided. 5. A method for creating beam deflection data (DX, DY) of a charged particle beam exposure apparatus according to claim 1, wherein said first and second deflection means (12, 14A, 14B).
The beam deflection data (DX, DY) is created based on non-use conditions in which the first and second deflecting means (12, 14A, 14B) are not used and use conditions in which the first and second deflecting means (12, 14A, 14B) are used. Method for creating deflection data of a charged particle beam exposure apparatus. 6. A method for producing deflection data of a charged particle beam exposure apparatus according to claim 5, wherein said beam deflection data (DX, DY) is produced by said first and second deflecting means (12, Under the non-use conditions of 14A and 14B), a cross-sectional image (EP) of the charged particle beam (11A) shaped in the region above the first deflecting means (12) is projected on the sample surface, and thereafter, 1. Second deflecting means (12, 14A,
Under the use condition of 14B), arbitrary deflection data (Da) is supplied to one of the first and second deflection means (12, 14A, 14B), and the deflection data (Da) is The charged particle beam (11
(A) and the first and second deflecting means (1).
2, 14A, 14B) are superimposed on the cross-sectional image (EP) of the charged particle beam (11A) under non-use conditions, and based on the superposition, deflection of other deflection means other than the one deflection means is performed. A method for generating deflection data for a charged particle beam exposure apparatus, comprising calculating data (Db, Dc, Dd). 7. A method for producing deflection data of a charged particle beam exposure apparatus according to claim 5, wherein said beam shaping means (13) is detached from an optical axis (C) of the charged particle beam (11A). A charged particle beam exposure apparatus for producing the beam deflection data (DX, DY) based on a state in which the beam shaping means (13) is taken into the optical axis (C) of the charged particle beam (11A). How to create deflection data. 8. A plurality of block mask patterns (BPi, [i = 1, 2,...) Based on the beam deflection data (Da).
i)) to deflect the charged particle beam (11A) into one
And a pattern shaping process of the charged particle beam (11A) based on the first deflecting process is performed to obtain another deflecting data (Dc, Dd) associated with the beam deflecting data (Da). A charged particle beam exposure method, comprising: performing a second deflection process of returning a charged particle beam (11A), which has been pattern-shaped based on it, to an optical axis (C). 9. The charged particle beam exposure method according to claim 8, wherein after the second deflection processing, the object to be exposed is based on another deflection processing of the charged particle beam.
A charged particle beam exposure method, comprising: