JPH09274884A - Electron beam exposure apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the strain of a transfer image due to heat radiation of a mask and at the same time to form a transfer image at high resolution without Coulomb blur. SOLUTION: Electron beam 36, which is emitted out of an electron gun 12 is accelerated by an electric field formed by an acceleration high voltage electric power source 6 and at the same time illuminates a stencil mask by an illumination lens 14, is retarded at the time when passing a retarding electrode 16 and the stencil mask 18 and radiated to the stencil mask 18, so that the heating of the mask is suppressed and thermal strain of a transfer image is prevented. The retarded electron beam is accelerated again by a re- accelerating electrode 20, so that Coulomb blur can be prevented and a resist 32 can be exposed at high resolution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam exposure apparatus, and more particularly to high definition semiconductor integrated circuits,
The present invention relates to an electron beam exposure apparatus suitable for transferring a high density pattern.

[0002]

2. Description of the Related Art Conventionally, in a lithography process for manufacturing a semiconductor integrated circuit, a liquid crystal display substrate, etc., i-line, g-line etc. of an ultra-high pressure mercury lamp are used as exposure light, KrF, A
An optical exposure device using an rF excimer laser beam as an exposure light source is mainly used. In addition, an electron beam exposure apparatus and an X-ray exposure apparatus that use a charged particle beam such as an electron beam are also used.

Among these, for example, a conventionally known exposure apparatus using an electron beam is provided with an electron beam on which the electron beam is focused, a photoresist (hereinafter referred to as "resist" as appropriate), etc. on its surface. There is a spot beam exposure apparatus that performs drawing exposure by scanning on a photosensitive substrate such as a wafer coated with the photosensitive material. In this spot beam exposure apparatus, since the electron beam is exposed like a single stroke, the throughput is inevitably low and it is not suitable for practical use.

Therefore, as a high-throughput exposure apparatus, a light exposure apparatus such as a stepper is relatively often used, but with the miniaturization of a circuit pattern, the limit of the optical exposure apparatus has begun to appear and disappear, and recently. Therefore, the development of an electron beam exposure apparatus capable of obtaining a high throughput comparable to that of an optical exposure apparatus such as a stepper is urgently needed. Examples of such an electron beam exposure apparatus include an electron beam batch transfer type exposure apparatus.
This electron beam batch transfer type exposure apparatus uses an original plate called a stencil mask made of silicon (Si) or the like in which a pattern-shaped opening for each chip of a silicon wafer (hereinafter simply referred to as “wafer”) is formed. The batch exposure is sequentially performed.

In such an electron beam collective exposure apparatus, an electron beam emitted from an electron gun is accelerated by an electric field, and an electron beam formed by an aperture is applied to a stencil mask, where the electron beam selectively transmitted. Only the resist is applied to the resist applied on the wafer, and an image of the mask pattern is transferred and formed on the resist.

[0006]

As described above, the conventional electron beam exposure apparatus has become an electron beam collective exposure apparatus, and finally comes to a practical stage in terms of throughput.

However, in the electron beam collective exposure apparatus described above, the stencil mask used is 2 to 50 μm.
It is formed of a silicon (Si) thin film having a film thickness of about m, and is irradiated with an electron beam accelerated to about 10 to 50 keV. At this time, in the mask portion other than the opening portion of the stencil mask, some electrons may be transmitted while being scattered by the acceleration voltage, but most of the electrons are absorbed in the silicon thin film to heat the stencil mask. As described above, when the stencil mask is irradiated with the electron beam, the temperature of the mask is raised, and the transferred image is distorted due to thermal expansion of the mask itself.

On the other hand, as the exposure pattern becomes finer, it is necessary to increase the resolution of the electron beam exposure apparatus to reduce the image blur. To this end, it is necessary to further accelerate the electron beam. There is. That is, each electron emitted from the electron gun has a negative charge, and the beam tries to spread due to the mutual repulsive force (Coulomb force), but by accelerating the electron, the spread of the beam is suppressed and the image Bokeh (Coolong bokeh) can be reduced. However, if the electron beam is accelerated to a high degree, the temperature of the stencil mask will be further increased, and the distortion of the transferred image will be further increased.

On the other hand, it may be possible to suppress the heating of the mask by reducing the film thickness of the stencil mask to increase the electron beam transmittance. However, when a stencil mask made of, for example, a thin silicon film having a thickness of about 2 μm is irradiated with an electron beam accelerated with an acceleration voltage of 100 kV, about 2% of the mask incident power of electrons is accumulated in the mask and heat is generated. Therefore, distortion of the transferred image due to thermal expansion cannot be avoided. Further, it is very difficult to form a stencil mask having a film thickness of less than 2 μm, and there is a limit to thinning the mask.

The present invention has been made under such circumstances, and an object thereof is an electron beam exposure apparatus capable of preventing distortion of a transferred image due to heat generation of a mask and obtaining a transferred image of high resolution with little Coulomb blur. To provide.

[0011]

The invention according to claim 1 is an electron beam exposure apparatus for transferring an image of a pattern formed on a mask (18) onto a photosensitive substrate (34), wherein a predetermined voltage is applied. An electron beam source (12) that is applied to generate an electron beam;
A deceleration means (1) for decelerating the electrons generated from the electron beam source and accelerated by the applied voltage near the mask.
6, 18, 28); a projection lens (24) arranged between the mask and the photosensitive substrate; and a reaccelerating means (20, 30) for reaccelerating the electron beam after passing through the mask.

According to this, the electrons generated from the electron beam source (for example, the electron gun) and accelerated by the applied voltage are once decelerated by the deceleration means provided near the mask, so that the electrons move during irradiation of the mask. Since the energy is small and the amount of heat generated is small even when absorbed by the mask, thermal distortion of the mask is prevented. Further, the electrons that have been decelerated and transmitted through the mask are accelerated again by the re-accelerating means, so that high-resolution exposure is performed in which the influence of Coulomb blur due to the Coulomb force acting between the electrons is minimized.

According to a second aspect of the present invention, in the electron beam exposure apparatus according to the first aspect, the distortion correcting means (2) for correcting the image distortion of the electron beam re-accelerated by the re-accelerating means.
2) is further included.

According to this, since the image distortion of the electron beam re-accelerated by the re-acceleration means is corrected by the distortion correction means, a proper transferred image can be obtained.

[0015] The third aspect of the present invention is the first or second aspect.
In the electron beam exposure apparatus described in the paragraph 1, the deceleration means is a deceleration electrode (16) that forms a space region of the same potential as the mask in front of the mask.

According to this, since the deceleration electrode for forming the space area having the same potential as the mask is provided in front of the mask as the deceleration means, it is possible to sufficiently decelerate the accelerated electrons and allow the electrons to pass through the mask. Therefore, the heat generation amount of the mask can be suppressed low.

The invention described in claim 4 is the first or second invention.
In the electron beam exposure apparatus described in the paragraph 1, the deceleration means is the mask (18) to which a deceleration voltage is applied.

According to this, since the deceleration voltage is applied to the mask as the deceleration means, it becomes possible to decelerate the accelerated electrons with a simple structure to allow the electrons to pass through the mask, thereby reducing the amount of heat generated by the mask. It can be kept low.

According to a fifth aspect of the present invention, in the electron beam exposure apparatus according to any one of the first to fourth aspects, the mask (18) is a stencil mask in which openings having a predetermined pattern shape are formed. Is characterized in that.

According to this, since the stencil mask in which the openings of the predetermined pattern shape are formed is used as the mask, the life is extended as compared with, for example, a photoelectric mask made of a photoelectric film such as a photoelectric batch exposure apparatus. can do.

According to a sixth aspect of the present invention, in the electron beam exposure apparatus according to any one of the first to fifth aspects, the projection lens (24) is an electromagnetic lens having a predetermined reduction magnification. Characterize.

According to this, since the electromagnetic lens having a predetermined reduction magnification is used as the projection lens, it is possible to perform the reduced batch exposure of the mask pattern, and even when the pattern is miniaturized, as compared with the case of equal magnification transfer. The manufacturing (creating) of the mask becomes easy.

According to a seventh aspect of the present invention, in the electron beam exposure apparatus according to any one of the first to sixth aspects, the mask (18) is formed of a silicon material having a film thickness of 10 μm or less, The deceleration means controls the energy of the electron beam accelerated by the voltage of 75 kV to 200 kV applied to the electron beam source to be less than the energy absorbed by the mask when the acceleration voltage is applied, for example, 3 keV or less. It is characterized by slowing down.

According to this, since the mask is formed of the silicon-based material having a film thickness of 10 μm or less, the heat generation amount of the mask can be suppressed to a certain amount or less. In addition to this, when the electron beam accelerated by the voltage applied to the electron beam source is directly irradiated on the mask, the energy of the electron beam is decelerated so that the energy is equal to or less than the energy absorbed by the mask. It employs a deceleration means that The deceleration means decelerates the electron beam so as not to heat the mask above a predetermined temperature because the temperature rise of the mask due to electron beam irradiation depends on the acceleration voltage of the electron beam and the film thickness of the mask.

For example, when an accelerating voltage is 100 kV and a mask made of a silicon-based material having a film thickness of 2 μm is used, 2 kV of energy is absorbed in the mask (in the case of a scattering mask), and the energy of the electron beam is also 2 keV.
It may be decelerated so as to be below (here, 1/50 or less) (becomes an absorption mask). Further, when a mask having a film thickness of 10 μm is used at the same accelerating voltage, 11 kV of energy is absorbed in the mask (in the case of a scattering mask), so that the electron beam energy is also 11 kV.
The speed may be reduced so as to be equal to or lower than eV (becomes an absorption mask). In this way, by temporarily decelerating the electron beam and irradiating the mask, the thermal strain of the mask due to the electron beam irradiation can be suppressed within a range that does not affect the exposure.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION

<< 1st Embodiment >> Hereinafter, 1st Embodiment of this invention is described based on FIG.

FIG. 1 schematically shows the structure of an electron beam exposure apparatus 10 according to the first embodiment. This electron beam exposure apparatus 10 accelerates electrons emitted from an electron gun to a required energy in an electric field, decelerates them in front of a mask, and re-accelerates the electrons to an energy required to obtain a transferred image after passing through the mask. And an electron beam collective exposure apparatus for exposing a resist applied on the surface of a silicon wafer (hereinafter referred to as “wafer”) as a photosensitive substrate.

This electron beam exposure apparatus 10 includes an electron gun 12 as an electron beam source, an illuminating lens 14 for converting an electron beam emitted from the electron gun 12 into a substantially parallel beam, a deceleration electrode 16 for decelerating the electron beam, and a mask. As a stencil mask 1
8, re-acceleration electrode 20 for re-accelerating the electron beam that has been decelerated and transmitted through the opening of the mask, distortion corrector 22 as a distortion correction means for correcting the distortion of the re-accelerated electron beam, projection lens for reducing projection exposure A reduction projection lens 24, an acceleration high-voltage power supply 26 for applying an acceleration voltage for accelerating the electrons emitted from the electron gun 12, and a deceleration power supply for applying a deceleration voltage for decelerating the electrons to the deceleration electrode 16 and the stencil mask 18. 28, a high-voltage power supply 30 for re-acceleration for applying a re-acceleration voltage for re-accelerating the electrons transmitted through the stencil mask 18 to the re-acceleration electrode 20, and the like. In this electron beam exposure apparatus 10, a resist 3 is used as a photosensitive material on its surface as a photosensitive substrate.
The wafer 34 coated with 2 is used, and the resist 3
2 forms an image forming surface.

The electron gun 12 generates an electron beam, and the electron beam is emitted radially from the electron gun 12. Further, the electron gun 12 is applied with an accelerating voltage (for example, 50 kV) from the accelerating high-voltage power supply 26, and accelerates the electron beam to the energy required to suppress the spread due to the Coulomb effect.

The illuminating lens 14 is an electromagnetic lens that changes the direction of the electron beam radially emitted from the electron gun 12. The illuminating lens 14 causes the stencil mask 18 to irradiate the stencil mask 18 with a required area of the mask. A beam is formed to illuminate.

The deceleration electrode 16 is arranged above the stencil mask 18 (on the side of the electron gun 12), and by applying a deceleration voltage from the deceleration power supply 28, a spatial region having the same potential as that of the stencil mask 18 described later is formed. This reduces the speed of the electrons. The principle of deceleration is that the electrons emitted from the electron gun 12 are accelerated by the acceleration voltage (for example, 50 kV) from the high voltage power source 26 for acceleration, and the deceleration electrode 1
6 and the stencil mask 18 are applied with a deceleration voltage lower than this (for example, 5 kV) to decelerate the electrons. That is, the energy of electrons when the deceleration voltage is applied is (deceleration voltage / acceleration voltage) = 5 kV / 50
kV = 1/10, and the electron energy is reduced to 1/10 in the first embodiment.

The stencil mask 18 is an original plate on which openings having a desired pattern shape are formed. For example, Si, Si
It is made of a thin film material such as C, SiO ₂ , SiN (Si ₃ O ₄ ). Therefore, the electron beam 36 is applied to the stencil mask 18
By irradiating the substrate, the electron beam 36 selectively passes through the opening, and it becomes possible to perform collective exposure with a bundle of electron beams having the same sectional shape as the shape (pattern shape) of the opening. The thickness of the stencil mask 18 is determined depending on the amount of deceleration of electrons by the deceleration electrode 16, and here, the number of electrons is 1
Since the speed is reduced to / 10 5 keV, a stencil mask made of Si is formed to a thickness of about 50 μm. In the first embodiment, the stencil mask 18
A deceleration power supply 28 is also connected to the deceleration electrode 16 to form a deceleration region including a space to which a deceleration voltage is applied.

The re-acceleration electrode 20 has a stencil mask 18
Is arranged below (on the side opposite to the electron gun 12) and a re-accelerating voltage is applied from the high-voltage power source 30 for re-acceleration to re-accelerate the decelerated electron beam after passing through the stencil mask 18. . This reacceleration voltage is a voltage for reaccelerating the electrons that have passed through the stencil mask 18 to the energy required to expose the resist 32. Here, re-acceleration is performed at 50 kV, which is the same as the acceleration voltage when emitted from the electron gun 12.

Here, the distortion corrector 22 is arranged below the reacceleration electrode 20 (on the side opposite to the electron gun 12) and appropriately changes the course of the electron beam by changing the distribution of the magnetic flux density of the magnetic field. It is composed of an electromagnetic lens capable of. The distortion corrector 22 corrects the distortion generated when the electron beam is re-accelerated by the re-acceleration electrode 20. The installation position of the distortion corrector 22 is not limited to the above example.

The reduction projection lens 24 is an electromagnetic lens for performing reduction projection exposure, and passes through the stencil mask 18, is re-accelerated, and has its distortion corrected electron beam 38.
Pattern transfer image of a predetermined reduction ratio (here, 1/4
0) and the reduced image of the mask pattern is projected on the resist 32.

Next, the overall operation of the electron beam exposure apparatus 10 configured as described above will be described with reference to FIG.

An electron beam 36 is radially emitted from the electron gun 12, and the electron beam illuminates a necessary area of the mask by the action of the magnetic field formed by the illumination lens 14 arranged around the electron beam 36. . Then, the electron beam 36 is first accelerated by the acceleration voltage of 50 kV by the electric field formed by the high voltage power source 26 for acceleration applied to the electron gun 12.

The accelerated electron beam 36 is once decelerated in the deceleration region composed of the deceleration electrode 16 and the stencil mask 18 which are connected to the deceleration power source 28 and to which the deceleration voltage of 5 kV is applied, and then the stencil mask 18 is decelerated. It selectively passes through 18 apertures. In this way, the electron beam 36 is decelerated in front of the stencil mask 18 because the electron beam energy absorbed by the stencil mask 18 is made as small as possible to reduce the temperature rise of the mask, which results from the thermal expansion of the mask. This is to prevent distortion of the transferred image.

Next, the electron beam immediately after passing through the opening of the stencil mask 18 is re-accelerated by the re-acceleration electrode 20 to which the re-acceleration voltage (50 kV) from the high-voltage power source 30 for re-acceleration is applied, and the electron beam is emitted from the electromagnetic lens. The pattern formed on the stencil mask 18 by the reduction projection lens 24 becomes a wafer 34 at a predetermined reduction ratio (here, 1/40).
The image is projected onto the surface of the resist 32 (image forming surface). As a result, a 1/40 reduced image of the pattern having the same shape as the pattern formed on the stencil mask 18 is transferred onto the surface of the resist 32. Here, it is the resist 3 that re-accelerates the electron beam that has passed through the opening of the stencil mask 18.
This is because the energy required to expose 2 is accelerated and the influence of the Coulomb effect of the decelerated electron beam is reduced. That is, in the decelerated electron beam, the so-called Coulomb effect, which repels each other due to the negative charge of each electron and spreads, becomes remarkable,
By accelerating again, the spread of the beam is suppressed,
Coulomb blur can be reduced.

In this case, when the transferred image is distorted due to the re-acceleration of the electron beam, the distortion correction device 22 arranged after the re-acceleration electrode 20 corrects the distortion to obtain a proper transferred image. be able to.

As is clear from the above description, in the electron beam exposure apparatus 10 according to the first embodiment, the deceleration power supply 2 is used.
8, a voltage having the same potential as that of the stencil mask 18 is applied, a deceleration electrode 16 that forms a spatial region having the same potential as the stencil mask 18 constitutes deceleration means, and a high-voltage power supply 30 for re-acceleration applies an acceleration voltage. The reacceleration electrode 20 constitutes reacceleration means.

As described above, according to the electron beam exposure apparatus 10 of the first embodiment, the electron beam emitted from the electron gun 12 is once accelerated by the electric field and then the deceleration electrode 16 and the stencil to which the deceleration voltage is applied. Since the speed is reduced in the space area (deceleration area) formed by the mask 18,
The deceleration effect of the electron beam becomes great, and the stencil mask 1
The electron beam energy absorbed by 8 can be reduced to 1/10. As a result, the temperature rise of the mask due to the electron beam is reduced, and the distortion due to the thermal expansion of the mask can be suppressed. Further, the decelerated electron beam is re-accelerated by the re-acceleration electrode 20, so that the energy required for exposing the resist 32 is applied. Further, the re-acceleration of the electron beam can prevent Coulomb blurring due to the Coulomb effect, and even if the electron beam is distorted during the re-acceleration, the distortion corrector 22 can correct the distortion. It is possible to obtain a transferred image with a high resolution. Further, in the first embodiment, since the reduction projection lens 24 is used to perform the reduction projection exposure, the mask can be easily produced (manufactured) even if the pattern is miniaturized.

<< Second Embodiment >> Next, a second embodiment of the present invention will be described with reference to FIG. Here, the same components as those of the apparatus according to the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted or simplified.

FIG. 2 schematically shows the structure of an electron beam exposure apparatus 40 according to the second embodiment. In this electron beam exposure apparatus 40, intermediate deceleration of the electron beam is performed only by the stencil mask 18, and if there is an electron beam 62 scattered by the stencil mask 18, the electron beam 62 is removed by a filter, and the electron beam transmitted through the opening of the mask is removed. Re-acceleration is performed to perform batch exposure.

The electron beam exposure apparatus 40 differs from the electron beam exposure apparatus 10 according to the first embodiment shown in FIG. 1 in that only the stencil mask 18 to which a deceleration voltage is applied is decelerated without using the deceleration electrode 16. It is used as a means to decelerate the electron beam. Then, depending on the deceleration voltage value applied to the stencil mask 18, it is used as a scattering mask in which the electrons irradiated to the mask portion other than the opening are scattered and transmitted, or an absorption mask in which the electrons are not transmitted and not scattered. be able to. For example, the thickness of the stencil mask is 2 μm, the acceleration voltage of the acceleration high-voltage power supply 52 is 100 kV, and the deceleration voltage of the deceleration power supply 54 is 1 kV.
When V is set, the electron beam energy is 100-1.
= 99 (kV), the electron beam is decelerated to 1 kV. Since the electron beam cannot pass through the stencil mask, it becomes an absorption mask, and energy of 1 kV is absorbed in the mask. On the other hand, when the accelerating voltage of the accelerating high-voltage power supply 52 is not set to 100 kV for deceleration, a scattering mask is formed, but about 2 kV of energy is absorbed. Thus, the acceleration voltage is 100
In the case of kV, the heat generation of the mask can be reduced more than that of the scattering mask by reducing the speed to 2 kV or less.

The reduction projection lenses 42 and 46 are arranged by dividing the reduction projection lens into upper and lower parts corresponding to the projected image. Then, as shown in FIG.
In this embodiment, since the stencil mask 18 may be used as the scattering mask as described above, the spatial filter 44 that captures the scattered electrons 62 that are transmitted through the stencil mask 18 while being scattered to prevent the exposure by the scattered electrons.
Are arranged between the reduction projection lenses 42 and 46.

Next, the operation of the electron beam exposure apparatus 40 of the second embodiment shown in FIG. 2 configured as described above will be described. Electron beam 58 emitted from the electron gun 12
Is first accelerated by an accelerating voltage of 100 kV by the electric field generated by the accelerating high-voltage power supply 52. Although the electron beam 58 radiates radially, it illuminates the area required for the mask by the action of the magnetic field formed by the illumination lens 14 arranged around the electron beam 58.

The accelerated electron beam 58 is once decelerated by the stencil mask 18 connected to the deceleration power source 54 and applied with a deceleration voltage of 1 kV. In this way, the electron beam 58 is decelerated before the stencil mask 18 by reducing the electron beam energy absorbed by the mask to reduce the temperature rise of the mask and the distortion of the transferred image due to the thermal expansion of the mask. This is to minimize as much as possible.

Next, the electron beam immediately after passing through the opening of the stencil mask 18 has a reacceleration electrode 20 to which a reacceleration voltage (100 kV) from a reacceleration high-voltage power source 56 is applied.
Is accelerated again by the reduction projection lenses 42 and 46, which are electromagnetic lenses, to a predetermined reduction magnification (here, 1 /
In 4), the pattern formed on the stencil mask 18 is projected, and a transfer image (reduced image) of the mask pattern is formed on the surface of the resist 32 (image forming surface) on the surface of the wafer 34. Here, to re-accelerate the electron beam that has passed through the opening of the stencil mask 18 is to use the resist 32
This is for accelerating to the energy necessary for exposing to reduce the image blur (coulomb blur) due to the Coulomb effect, and for transferring the transfer image of the high resolution mask pattern to the resist 32 on the wafer 34.

Further, in the electron beam exposure apparatus 40 of the present embodiment, if distortion occurs in the transferred image when the electron beam is re-accelerated by the re-acceleration electrode 20, the distortion corrector 22 corrects the distortion. Therefore, a proper transferred image can be obtained.

In the electron beam exposure apparatus 40 of the present embodiment, the acceleration voltage of 100 kV and 30 μA is applied to the electron gun 12 by the high voltage power source 52 for acceleration, and the deceleration voltage of the power source 54 for deceleration is set to 1 kV. 56 reacceleration voltage 1
1 m of the stencil mask 18 under the exposure condition when the stencil mask 18 is made of silicon (Si) having a thickness of 2 μm (the case where the stencil mask 18 is used as the scattering mask under this exposure condition).
When the irradiation was performed with an irradiation time of 100 μsec with respect to the m-square, the temperature rise of the mask could be suppressed to about 2 ° C., and the pattern shift amount could be set to about 3 nm. Thus, the stencil mask is set to 10 μm or less (here, 2 μm), and the energy of the electron beam is equal to or less than the energy absorbed by the mask (here, 1 keV).
As a result, the amount of distortion due to thermal expansion of the mask can be suppressed to a range that does not hinder pattern exposure.

The exposure conditions when the stencil mask 18 is used as a scattering mask are such that when the deceleration power supply 54 is not used, the temperature of the mask rises to about 5 ° C. and the pattern shift amount is also about. It will be expanded to about 10 nm. As described above, in the second embodiment, it can be understood that the thermal strain hardly poses a problem if the exposure conditions satisfy the above conditions. When the stencil mask 18 is used as a scattering mask, the scattered electron beam 62 is generated, but it is captured by the spatial filter 44 shown in FIG.

As described above, according to the electron beam exposure apparatus 40 of this embodiment, the electron beam 58 to which the acceleration voltage is applied by the acceleration high-voltage power supply 52 is decelerated by the stencil mask 18 to which the deceleration voltage is applied. be able to. For this reason, the electron beam energy absorbed by the stencil mask 18 becomes small, so that the temperature rise of the mask is suppressed and the distortion due to the thermal expansion of the mask is suppressed. Further, the decelerated electron beam is re-accelerated by the re-acceleration electrode 20 to give energy required for exposing the resist 32, and Coulomb blur due to the Coulomb effect is prevented. Further, even if the electron beam is distorted at the time of reacceleration, the distortion is corrected by the distortion corrector 22,
A transferred image with high resolution can be obtained.

In the description of each of the above-mentioned embodiments, the batch transfer method by reduction exposure has been described, but an electron beam exposure apparatus for performing equal-magnification or enlargement exposure may be used. Further, the voltage values of the acceleration high-voltage power supply, the deceleration power supply, and the re-acceleration high-voltage power supply in each of the above-described embodiments are not limited to those in the above-described embodiments, and are within the ranges of the suitable exposure conditions described above. , Can take any value.

Further, in the present embodiment, it is considered that the temperature rise of the mask is suppressed by reducing the energy absorbed in the mask by decelerating the accelerated electron beam. For example, the energy of 100 keV is applied. Reverse the electron beam that you have with a mask or the like located in the middle.
It is also possible to accelerate to 0 keV and reduce the energy absorbed by using a scattering type mask to suppress the temperature rise of the mask.

[0056]

As described above, according to the present invention, it is possible to suppress the occurrence of image distortion due to thermal expansion of the mask as much as possible and to form a high-resolution transferred image without Coulomb blur. It has an excellent effect not found in.

In particular, according to the invention described in claim 6, since the projection lens is configured as an electromagnetic lens having a predetermined reduction ratio, the mask pattern can be projected on the photosensitive substrate at the reduction ratio. Since the mask can be easily manufactured, it is possible to sufficiently cope with the miniaturization of the pattern.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration of an electron beam exposure apparatus according to a first embodiment.

FIG. 2 is a diagram schematically showing a configuration of an electron beam exposure apparatus according to a second embodiment.

[Explanation of symbols]

10 Electron Beam Exposure Device 12 Electron Gun (Electron Beam Source) 14 Illumination Lens 16 Deceleration Electrode (Part of Deceleration Means) 18 Stencil Mask (Mask, Part of Deceleration Means) 20 Reacceleration Electrode (Part of Reacceleration Means) ) 22 distortion corrector (distortion correction means) 24 reduction projection lens (projection lens) 26 high-voltage power supply for acceleration 28 deceleration power supply (part of reduction means) 30 high-voltage power supply for re-acceleration (part of re-acceleration means) 34 wafer (Photosensitive substrate) 36 Electron beam (electron beam) 44 Spatial filter 52 High voltage power source for acceleration 54 Power source for deceleration (part of deceleration means) 56 High voltage power source for reacceleration (part of reacceleration means)

Claims (7)

[Claims] 1. An electron beam exposure apparatus for transferring an image of a pattern formed on a mask onto a photosensitive substrate, comprising: an electron beam source for generating an electron beam when a predetermined voltage is applied thereto; A decelerating means for decelerating the electrons accelerated by the applied voltage in the vicinity of the mask; a projection lens arranged between the mask and a photosensitive substrate; a reaccelerating means for reaccelerating the electron beam after passing through the mask. An electron beam exposure apparatus having: 2. The electron beam exposure apparatus according to claim 1, further comprising distortion correction means for correcting image distortion of the electron beam re-accelerated by the re-acceleration means. 3. The electron beam exposure apparatus according to claim 1, wherein the deceleration means is a deceleration electrode that forms a space region having the same potential as the mask in front of the mask. 4. The electron beam exposure apparatus according to claim 1, wherein the deceleration means is the mask to which a deceleration voltage is applied. 5. The electron beam exposure apparatus according to claim 1, wherein the mask is a stencil mask in which openings having a predetermined pattern shape are formed. 6. The electron beam exposure apparatus according to claim 1, wherein the projection lens is an electromagnetic lens having a predetermined reduction magnification. 7. The mask is formed of a silicon-based material having a film thickness of 10 μm or less, and the deceleration means accelerates the energy of an electron beam accelerated by a voltage of 75 kV to 200 kV applied to the electron beam source. 7. The electron beam exposure apparatus according to claim 1, wherein the electrons are decelerated so that the energy becomes equal to or less than the energy absorbed by the mask when a voltage is applied.