JPH11296922A - Device and method for exposure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposing device which corrects the variance of a spot system of laser beams for recording and the positional shifting of an irradiation position with high accuracy with a simple configuration and forms an accurate latent image and to provide an exposing method. SOLUTION: This exposing device 1 is provided with an acoustooptical element 3 which corrects the light intensity and irradiation position of laser beams emitted from a light source 2 and a feedback system which detects a part of the laser beams that permeate the element 3 and controls the acoustooptical element so as to make the light intensity and irradiation position of the laser beams what is desired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure method for irradiating a photoresist layer formed on a substrate with a laser beam, thereby forming a latent image on the photoresist layer in accordance with the trajectory of the laser beam. The present invention relates to an apparatus and an exposure method.

[0002]

2. Description of the Related Art As a recording medium, an optical disk having a pit or the like indicating an information signal formed on the surface of a disk substrate and an Al reflective film or a protective film formed on the disk substrate having the pit or the like has been widely used. I have.

The disk substrate of this optical disk is mainly formed by an injection molding method. The injection molding method
For example, in a cavity of a pair of molds, a stamper in which the pits and the like of the disk substrate are formed with a concavo-convex shape of a reversal pattern is disposed, and a disk material heated and melted is injected into the cavity of the mold, and the disk substrate is removed. It is a molding method.

[0004] A stamper used in this injection molding method is formed as follows.

[0005] First, for example, the main surface of a disk-shaped glass substrate having a diameter of about 200 mm and a thickness of several mm, which is precisely polished on the surface, is provided with an adhesion reinforcing agent or the like, and has a wavelength sufficient for a recording laser light source. Photoresist with high sensitivity has a thickness of 0.1
It is evenly applied with a thickness of about μm. Then, the organic solvent of the photoresist is volatilized, and a photoresist layer is formed on the glass substrate.

Next, the glass substrate on which the photoresist layer has been formed is set in an exposure apparatus. Then, the exposure apparatus focuses the recording laser beam on the photoresist on the glass substrate with a spot size of about 0.5 μm.

The exposure apparatus spirally irradiates the laser beam onto the resist layer of the glass substrate while modulating the intensity of the laser beam based on the input recording signal, so that the resist layer corresponds to predetermined pits and grooves. A latent image having an uneven pattern is formed.

Next, the resist layer on which the latent image is formed is developed with an alkaline developer to form a resist master having an uneven pattern corresponding to predetermined pits and grooves.

Next, a metal film such as silver or nickel is formed on the main surface of the resist master having an uneven pattern by a method such as sputtering, vapor deposition, or electroless plating.

Next, the resist master on which the metal coating is formed is set in an electroplating apparatus, and electroplating is performed using the metal coating as an electrode to form an electroplating layer on the main surface of the resist master. Is done.

Next, the resist master is peeled off from the metal film and the electroplating layer, and the excess metal film is removed by pressing to complete the stamper.

By the way, as an exposure apparatus used in the above-described stamper manufacturing process, an exposure apparatus 100 as shown in FIG. 4 has been conventionally used. The exposure apparatus 100 shown in FIG. 4 is provided on a light source 101 that continuously oscillates a recording laser beam, and is disposed on an optical path of the recording laser beam emitted from the light source 101, and outputs an optical output of the recording laser beam. Output control unit (APC: Auto Power Control)
An AOM (Acousto-optic modulator) 103 for modulating a recording laser beam whose optical output is controlled by the APC 102 based on a recording signal;
An objective lens 104 for condensing the recording laser light modulated by the OM 103 and irradiating the light on the resist layer is configured as a main component.

In the exposure apparatus 100,
The light source 101, the APC 102, and the AOM 103 are provided on a fixed optical surface plate (not shown), and the objective lens 104 is provided on a feed surface plate 105 that is moved in the radial direction of the glass substrate on which the resist layer is formed. Have been.

The glass substrate on which the resist layer has been formed is chucked on an air spindle that rotates with high rotational accuracy.

When a latent image having a concavo-convex pattern corresponding to predetermined pits and grooves is formed on the resist layer by the exposure apparatus 100 configured as described above, first, a recording laser beam such as a Kr ion laser is emitted from the light source 101. Is emitted.

The recording laser light emitted from the light source 101 is applied to an electro-optical element (EOM: El
ectrooptic modulator) 106 and a polarizing beam splitter (PBS) 107, a part of which is reflected by a half mirror 108, and a part of which passes through the half mirror 108 to detect the output of the recording laser light. Incident on the photodetector 109.

The electro-optical element 106 changes the plane of polarization of the transmitted recording laser beam based on the information fed back by the photodetector 109. As a result, the output of the recording laser light transmitted through the polarization beam splitter 107 is adjusted to be always constant.

The recording laser light reflected by the half mirror 108 enters the AOM 103. This AOM1
Numeral 03 modulates the intensity of the incident recording laser light based on the recording signal.

The recording laser light intensity-modulated by the AOM 103 is incident on an objective lens 104 disposed on a feed platen 105 so as to face a main surface of a glass substrate on which a resist layer is formed.

The recording laser light incident on the objective lens 104 is condensed by the objective lens 104 and is irradiated onto a resist layer formed on a glass substrate which rotates with the rotation of the air spindle.

The exposure apparatus 100 includes the objective lens 1
The resist plate 131 is spirally scanned by irradiating the resist layer with recording laser light condensed by the objective lens 104 while moving the feed platen provided with 04 in the radial direction of the glass substrate. Then, a latent image having a concavo-convex pattern corresponding to predetermined pits and grooves is formed on the resist layer.

Although only the main components of the exposure apparatus 100 have been described above, the exposure apparatus 100 may be, for example, a condensing lens for condensing a recording laser beam or a recording laser beam depending on the purpose of use. And various optical systems such as a polarizing optical system for changing the polarization state of the recording laser light and a folding mirror for bending the optical path of the laser light.

[0023]

By the way, in the above-mentioned optical discs and the like, in order to increase the recording density and increase the storage capacity, narrower tracks and shorter pit mark lengths have been attempted.

Accordingly, in an exposure apparatus for forming a concavo-convex pattern corresponding to pits and grooves on an optical disk, tolerances for variations in spot diameter of a recording laser beam and positional deviation of an irradiation position have become strict.

In the above-described conventional exposure apparatus 100, the light output of the recording laser beam emitted from the light source 101 by the APC 102 is kept constant, thereby suppressing the variation in the spot system of the recording laser beam. However, the recording laser light is incident on the objective lens 104 through various optical systems after the light output is set to a constant value by the APC 102. Will occur.

In the conventional exposure apparatus 100,
Although the feed width of the feed platen 105 that supports the objective lens 104 is finely adjusted to correct the positional deviation of the irradiation position, such mechanical positional correction allows the positional deviation to be corrected with high accuracy. It is difficult to correct. In addition, if a new means is provided to correct the displacement of the irradiation position, the number of components increases and the size of the apparatus increases.

Accordingly, the present invention provides an exposure apparatus capable of forming a highly accurate latent image by correcting the variation of the spot system of the recording laser beam and the displacement of the irradiation position with high accuracy by simplifying the configuration. And an exposure method.

[0028]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an exposure apparatus according to the present invention has an acousto-optic device for correcting the light intensity and irradiation position of a laser beam emitted from a light source, and an acousto-optic device. A feedback system is provided for detecting a part of the laser light transmitted through the element and controlling the acousto-optical element so that the light intensity and the irradiation position of the laser light become desired.

According to this exposure apparatus, the feedback system detects a part of the laser beam emitted from the light source and transmitted through the acousto-optic device. Then, the feedback system controls, for example, the intensity of the carrier and the frequency of the carrier of the acousto-optic device based on a part of the detected laser light. The acousto-optic device corrects the light intensity of the laser light by controlling the intensity of the carrier by the feedback system, and corrects the irradiation position of the laser light by controlling the frequency of the carrier.

The exposure apparatus can perform accurate exposure by correcting both the light intensity and the irradiation position of the laser beam as described above.

Further, in the exposure apparatus according to the present invention, it is desirable that the acousto-optic element for correcting the light intensity and the irradiation position of the laser beam modulates the intensity of the laser beam according to the recording signal.

The exposure apparatus has a function of correcting the light intensity and the irradiation position of the laser beam and a function of modulating the intensity of the laser light in the acousto-optic element in this way, thereby simplifying the configuration and forming a latent image of a desired pattern. It can be formed with high accuracy.

Further, in the exposure apparatus according to the present invention, the acousto-optic element and the feedback system are provided on a feed platen for movably supporting an objective lens for condensing a laser beam and irradiating the recording medium. It is desirable to be provided.

By providing the acousto-optic device and the feedback system on the feed platen as described above, the exposure apparatus can correct even errors in the feed operation of the feed platen and the like. Since the acousto-optic element and the feedback system are provided at a position close to the objective lens, it is possible to correct the light intensity and the irradiation position of the laser beam with higher accuracy.

According to the exposure method of the present invention, in order to solve the above-mentioned problems, an acousto-optic device and a part of the laser beam transmitted through the acousto-optic device are placed on the optical path of the laser beam emitted from the light source. Arrange feedback system to detect,
The acousto-optic device is controlled based on a part of the laser light detected by the feedback system, so as to correct the light intensity and the irradiation position of the laser light.

According to this exposure method, for example, based on a part of the laser light detected by the feedback system,
By controlling the carrier intensity and carrier frequency of the acousto-optical element, both the light intensity and the irradiation position of the laser beam are corrected, and accurate exposure can be performed.

Further, in the exposure method according to the present invention, it is desirable to modulate the intensity of the laser beam by using an acousto-optic device for correcting the light intensity and the irradiation position of the laser beam. As described above, by providing the acousto-optical element with the function of correcting the light intensity and irradiation position of the laser beam and the function of modulating the intensity, a latent image of a desired pattern with high accuracy can be easily formed. .

Further, in the exposure method according to the present invention, the acousto-optic device and the feedback system may be mounted on a feed platen for movably supporting an objective lens for condensing a laser beam and irradiating the object with a laser beam. It is preferable that the light intensity and the irradiation position of the laser beam be corrected on the feed platen.

As described above, by correcting the light intensity and the irradiation position of the laser beam on the feed platen, it is possible to correct even the error of the feed operation of the feed platen. In addition, by providing the correction means and the feedback system at a position close to the objective lens, it is possible to correct the light intensity and the irradiation position of the laser beam with higher accuracy.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An exposure apparatus according to the present invention is used for producing a stamper used for injection molding a disk substrate of a disk-shaped recording medium such as an optical disk having pits or grooves or a magneto-optical disk. This is for irradiating a laser beam onto a resist layer formed on a glass substrate to form a latent image of a predetermined pattern corresponding to pits and grooves of an optical disk on the resist layer.

Hereinafter, an embodiment of this exposure apparatus will be described with reference to the drawings.

(First Embodiment) As shown in FIG. 1, an exposure apparatus 1 according to a first embodiment has, as a basic configuration, a light source 2 for emitting a recording laser beam, and a light source 2 for emitting a recording laser beam. Acousto-optical element 3 arranged on the optical path of the recording laser light
A half mirror 4 disposed on the optical path of the recording laser light transmitted through the acousto-optic element 3, and a photodetector 5 disposed on the optical path of the recording laser light transmitted through the half mirror 4
And an objective lens 6 disposed on the optical path of the recording laser light reflected by the half mirror 4, supporting the objective lens 6, and moving the objective lens 6 in the radial direction of the glass substrate on which the resist layer is formed. And a feed platen 7 to be moved.

A controller 8 is connected between the photodetector 5 and the acousto-optic device 3. In the exposure apparatus 1, the photodetector 5 and the controller 8 constitute one feedback system.

A folding mirror 9 is provided on the optical path of the recording laser light emitted from the light source 2.

The glass substrate on which the resist layer has been formed is chucked on an air spindle that rotates with high rotational accuracy.

As the light source 2, a gas laser which emits a laser beam having a photosensitive wavelength of a resist material constituting the resist layer is used. Specifically, for example, when the resist material constituting the resist layer is a positive type, an Ar laser having a wavelength of 458 nm, a He-Cd laser having a wavelength of 442 nm,
An ion laser type gas laser that emits a Kr laser or the like having a wavelength of 413 nm is used. The recording laser beam emitted from the light source 2 is incident on the acousto-optic device 3 after the optical path is bent by the folding mirror 9.

The acousto-optic element 3 is composed of, for example, an acousto-optic modulator (AOM: Acousto Optic Modulator) or an acousto-optic deflector (AOD: Acousto Optic Deflector). These optical elements are made of, for example, a TeO ₂ crystal, and use a phase diffraction grating based on a change in a refractive index generated in the crystal by supplying an ultrasonic wave to generate a first-order diffracted light in Bragg diffraction or Debye-Cias effect. Is utilized in that the diffraction angle is substantially proportional to the frequency of the supplied ultrasonic wave, and the intensity of the first-order diffracted light in the Bragg diffraction or the Debye-Cias effect is substantially proportional to the intensity of the supplied ultrasonic wave. That is, the acousto-optic device 3
Changes the emission angle of the first-order diffracted light of the incident recording laser light in accordance with the frequency of the ultrasonic wave (carrier) supplied from an ultrasonic wave generation circuit (not shown), and further supplies the supplied ultrasonic wave (carrier). The intensity of the first-order diffracted light of the incident recording laser light is changed in accordance with the intensity of the recording laser light.

The exposure apparatus 1 uses the first-order diffracted light emitted from the acousto-optic element 3 as recording laser light.

The acousto-optic device 3 also functions as a modulator for modulating the intensity of the recording laser beam based on the recording signal. That is, the ultrasonic wave modulated according to the recording signal is supplied to the acousto-optic
Performs intensity modulation of the recording laser light based on the ultrasonic waves.

In the exposure apparatus 1, the intensity of the recording laser beam is modulated by the acousto-optic device 3 and the light output and emission angle of the recording laser beam are adjusted. It is possible to form a latent image with high accuracy according to a recording signal on the resist layer while simplifying the configuration.

The half mirror 4 transmits a part of the recording laser light transmitted through the acousto-optic element 3 and guides it to the photodetector 5, and reflects a part of the recording laser light transmitted through the acousto-optic element 3. To the objective lens 6.

The photodetector 5 is composed of, for example, a two-part photodetector, receives the recording laser light transmitted through the half mirror 4, converts the received laser light into an electric signal (light receiving signal), and supplies it to the controller 8.

The controller 8 controls the acousto-optic device 3 based on the light receiving signal supplied from the photodetector 5.
Specifically, the controller 8 monitors the light intensity of the recording laser light transmitted through the acousto-optic element 3 from the sum signal of the light receiving signals supplied from the photodetector 5 composed of a two-part photodetector, and Then, the intensity of the carrier supplied to the acousto-optic element 3 is adjusted so that the light intensity of the recording laser beam transmitted through the acousto-optic element 3 has a predetermined value. Further, the controller 8 monitors the emission angle of the recording laser beam passing through the acousto-optic element 3 from the difference signal of the light receiving signal supplied from the photodetector 5, and based on this, transmits the acousto-optic element 3. The frequency of the carrier supplied to the acousto-optic device 3 is adjusted so that the emission angle of the recording laser light to be obtained has a predetermined value.

That is, in the exposure apparatus 1, when the light intensity of the recording laser beam transmitted through the acousto-optic device 3 deviates from a predetermined value, the controller 8 controls the carrier supplied to the acousto-optic device 3. The intensity is adjusted,
The light intensity of the recording laser light is corrected so as to be a predetermined value. Further, when the emission angle of the recording laser light transmitted through the acousto-optic element 3 is deviated from a predetermined value, the frequency of the carrier supplied to the acousto-optic element 3 is adjusted by the controller 8, and the recording laser light is adjusted. Is corrected so that the emission angle of the light beam becomes a predetermined value. The exposure position is corrected by correcting the emission angle of the recording laser light emitted from the acousto-optic element 3.

The objective lens 6 condenses the recording laser light reflected by the half mirror 4 and chucks the condensed recording laser light on an air spindle that rotates with high rotational accuracy. Irradiate the upper resist layer.

The objective lens 6 is supported on a feed platen 7 movably provided in the radial direction of the glass substrate, and moves in the radial direction of the glass substrate with the movement of the feed platen 7. . As a result, the recording laser light condensed by the objective lens 6 irradiates the resist layer on the rotating glass substrate in a spiral manner.

When exposure is performed by the exposure apparatus 1 having the above-described configuration, first, the glass substrate on which the resist layer is formed is chucked by an air spindle (not shown) and formed on the glass substrate by the light source 2. The recording laser light having the photosensitive wavelength of the resist layer thus emitted is emitted.

The recording laser light emitted from the light source 2 is
The optical path is bent by the folding mirror 9 and enters the acousto-optic element 3. The recording laser light incident on the acousto-optic device 3 is intensity-modulated by the acousto-optic device 3 in accordance with a recording signal.

The recording laser light intensity-modulated by the acousto-optic device 3 is partially transmitted through the half mirror 4 and partially reflected by the half mirror 4.

The recording laser light transmitted through the half mirror 4 is received by the photodetector 5. And the photodetector 5
The recording laser light received by the optical detector 5 is converted into an electric signal by the photodetector 5 and supplied to the controller 8.

The controller 8 detects the light intensity and the amount of deviation of the diffraction angle of the first-order diffracted light emitted from the acousto-optic element 3 based on the light receiving signal supplied from the photodetector 5.
Then, the controller 8 changes the intensity and frequency of the carrier supplied to the acousto-optic element 3 so that the light intensity and the diffraction angle of the first-order diffracted light emitted from the acousto-optic element 3 have predetermined values.

As described above, in the exposure apparatus 1 according to the present invention, by performing feedback control on the acousto-optic element 3 by the photodetector 5 and the controller 8, the first-order diffraction emitted from the acousto-optic element 3 is performed. The light, that is, the light intensity and emission angle of the recording laser light are corrected. Therefore, according to the exposure apparatus 1, variation in the diameter of the exposure pattern and displacement of the exposure position are suppressed, and a precise latent image can be formed on the resist layer.

The recording laser light reflected by the half mirror 4 is supported by the feed platen 7 and enters the objective lens 6 which moves in the radial direction of the rotating glass substrate as the feed platen 7 moves. . Then, the recording laser light is condensed by the objective lens 6 and is applied to a resist layer formed on the glass substrate.

As a result, a desired latent image corresponding to the recording signal is formed with high accuracy on the resist layer.

As described above, according to the exposure apparatus 1 of the present invention, the acousto-optic element 3 is arranged on the optical path of the recording laser beam emitted from the light source 2 and A feedback system including a photodetector 5 and a controller 8 is provided on the optical path of the transmitted recording laser light, and the light intensity and the irradiation position of the recording laser light transmitted through the acousto-optic element 3 are corrected by controlling the feedback system. Therefore, a latent image with high accuracy corresponding to the pits and grooves of the optical disk can be formed on the resist layer.

The exposure apparatus 1 includes an acousto-optic device 3
However, since it has a function of correcting the light intensity and irradiation position of the recording laser beam and a function of modulating the intensity in accordance with the recording signal, it is possible to simplify the configuration and to provide an accurate latent image on the resist layer. It is possible to form an image.

Although the basic configuration of the exposure apparatus 1 has been described above, the exposure apparatus 1 may be configured, for example, to collect a recording laser beam or a recording laser beam in parallel according to the purpose of use. Various optical systems such as a collimator lens for converting light, a polarization optical system for changing the polarization state of the recording laser light, and a folding mirror for bending the optical path of the laser light may be appropriately provided.

In the above, an example in which only the objective lens 6 is provided on the feed platen 7 has been described. However, the exposure apparatus according to the present invention is not limited to this example. An acousto-optic element 3, a half mirror 4, a photodetector 5, and a controller 8 may be provided in the scanner to correct the light intensity and irradiation position of the recording laser light on the feed platen 7. As described above, when the light intensity and the irradiation position of the recording laser beam are corrected on the feed base 7, it is possible to correct even the error of the feed operation of the feed base 7. At the same time, feedback control can be performed at a position close to the objective lens 6, and the light intensity and irradiation position of the recording laser light can be corrected with higher accuracy.

In the above, an example in which the acousto-optic device 3 has a function of correcting the light intensity and irradiation position of the recording laser light and a function of modulating the intensity of the recording laser light has been described. The exposure apparatus according to the present invention is not limited to this example. In addition to the acousto-optic device 3 that corrects the light intensity and irradiation position of the recording laser light, other optical devices that perform intensity modulation of the recording laser light are used. An element may be provided.

(Second Embodiment) Next, a description will be given of a second embodiment of the exposure apparatus according to the present invention.

The exposure apparatus of the second embodiment separates the optical path of the recording laser light emitted from the light source into two,
An acousto-optic device and a feedback system are provided on each optical path.

That is, as shown in FIG. 2, the exposure apparatus 10 of the second embodiment includes a light source 11 for emitting a recording laser beam, and the recording laser beam emitted from the light source 11 The light is separated by a first half mirror 12 disposed on the optical path. On the first optical path of the recording laser light reflected by the first half mirror 12, a first acousto-optic element 13 and on the optical path of the recording laser light transmitted through the first acousto-optic element 13 A second half mirror 14 disposed in the
And a first photodetector 15 disposed on the optical path of the recording laser light transmitted through the first photodetector 15. Further, a first controller 16 is connected between the first photodetector 15 and the first acousto-optic element 13, and the first photodetector 15 is connected to the first controller 16.
A first feedback system is configured by the first controller 16 and the first controller 16.

On the second optical path of the recording laser light transmitted through the first half mirror 12, there is provided a first folding mirror 17, and the recording laser beam whose optical path is bent by the first folding mirror 17. A second light source disposed on the optical path of the laser light
Acousto-optic element 18, a third half mirror 19 disposed on the optical path of the recording laser light transmitted through the second acousto-optic element 18, and the recording laser light transmitted through the third half mirror 19 And a second photodetector 20 disposed on the optical path of the second photodetector. Then, the second photodetector 20 and the second
Between the acousto-optic element 18 and the second controller 21
Are connected, and the second photodetector 20 and the second controller 21 constitute a second feedback system.

A polarizing beam splitter 22 is provided on the first optical path of the recording laser light reflected by the second half mirror 14. The polarizing beam splitter 22 includes a third half mirror 19 and the third half mirror 19.
The recording laser light of the second optical path reflected by the second folding mirror 23 disposed on the optical path of the recording laser light reflected by the half mirror 19 is also incident. Then, the recording laser light of the first optical path reflected by the second half mirror 14 passes through the polarization beam splitter 22, and is recorded by the second folding mirror 23 on the second optical path. Is reflected by the polarization beam splitter 22, so that the recording laser light on the first optical path and the recording laser light on the second optical path draw parallel trajectories.

The first optical path of the recording laser beam transmitted through the polarization beam splitter 22 and the polarization beam splitter 22
On the second optical path of the recording laser light reflected by
An objective lens 24 is provided. This objective lens 24
Is supported by a feed platen 25 which is movable in the radial direction of the glass substrate on which the resist layer is formed.

The glass substrate on which the resist layer has been formed is chucked on an air spindle that rotates with high rotational accuracy.

The respective optical elements constituting the exposure apparatus 10 of the second embodiment are the same as those of the exposure apparatus 1 of the first embodiment.
Since these are the same as the respective optical elements constituting, detailed description is omitted. Further, the exposure apparatus 10 according to the second embodiment
Also, the first acousto-optic element 13 and the second acousto-optic element 18 have both a function of correcting the light intensity and exposure intensity of the recording laser light and a function of modulating the intensity of the recording laser light. Like that.

When performing exposure by the exposure apparatus 10 having the above-described configuration, first, the glass substrate on which the resist layer is formed is chucked by an air spindle (not shown), and the light source 11 forms the glass substrate on the glass substrate. The recording laser light having the photosensitive wavelength of the resist layer thus emitted is emitted.

The optical path of the recording laser light emitted from the light source 11 is separated by the first half mirror 12.
The recording laser light reflected by the first half mirror 12 enters the first acousto-optic element 13. Then, the recording laser light incident on the first acousto-optic element 13 is intensity-modulated by the first acousto-optic element 13 according to the recording signal.

The recording laser light intensity-modulated by the first acousto-optic device 13 is partially transmitted through the second half mirror 14 and partially reflected by the second half mirror 14.

The recording laser light transmitted through the second half mirror 14 is received by the first photodetector 15. The recording laser light received by the first photodetector 15 is converted into an electric signal by the first photodetector 15 and supplied to the first controller 16.

The first controller 16 controls the light intensity of the first-order diffracted light emitted from the first acousto-optical element 13 and the shift amount of the diffraction angle based on the light receiving signal supplied from the first photodetector 15. Is detected. Then, the first controller 16 controls the first controller so that the light intensity and the diffraction angle of the first-order diffracted light emitted from the first acousto-optic element 13 have predetermined values.
The intensity and frequency of the carrier supplied to the acousto-optic element 13 are changed.

On the other hand, the recording laser light transmitted through the first half mirror 12 is reflected by the first folding mirror 17 and enters the second acousto-optic element 18. Then, the recording laser light incident on the second acousto-optic element 18 is intensity-modulated by the second acousto-optic element 18 according to the recording signal.

The recording laser light intensity-modulated by the second acousto-optic device 13 is partially transmitted through the third half mirror 19 and partially reflected by the third half mirror 19.

The recording laser light transmitted through the third half mirror 19 is received by the second photodetector 20. The recording laser light received by the second photodetector 20 is converted into an electric signal by the second photodetector 20 and supplied to the second controller 21.

The second controller 21 controls the light intensity and the deviation of the diffraction angle of the first-order diffracted light emitted from the second acousto-optic element 18 based on the light receiving signal supplied from the second photodetector 20. Is detected. Then, the second controller 21 controls the second order so that the light intensity and the diffraction angle of the first-order diffracted light emitted from the second acousto-optic element 18 have predetermined values.
The intensity and frequency of the carrier supplied to the acousto-optic element 18 are changed.

As described above, in the exposure apparatus 10, the first photodetector 15 and the first controller 16
Feedback control is performed on the first acousto-optical element 13, and the second photodetector 20 and the second controller 21
By performing feedback control on the second acousto-optic element 18, the first-order diffracted light emitted from the first and second acousto-optic elements 13, 18, ie, the light intensity and emission angle of the recording laser light Is corrected. Therefore, according to the exposure apparatus 10, variation in the diameter of the exposure pattern and displacement of the exposure position are suppressed, and a precise latent image can be formed on the resist layer.

The recording laser light of the first optical path reflected by the second half mirror 14 passes through the polarization beam splitter 22 and passes through the objective lens 2 supported by the feed platen 7.
4 is incident. In addition, the recording laser light in the second optical path reflected by the third half mirror 19 is reflected by the second folding mirror 23, and is reflected by the polarization beam splitter 2.
The light is reflected by 2 and is incident on the objective lens 24 supported on the feed platen 7.

The recording laser light incident on the objective lens 24 and condensed by the objective lens 24 on the first optical path and the second optical path is rotated by the objective lens 24 as the platen 7 moves. By moving in the radial direction of the glass substrate, the resist layer formed on the glass substrate is irradiated spirally.

As a result, two types of latent images having different patterns are simultaneously and accurately formed on the resist layer.

As described above, according to the exposure apparatus 10, the first acousto-optic element 13 is disposed on the first optical path of the recording laser beam, and the first acousto-optic element 13 is A first feedback system including a first photodetector 15 and a first controller 16 is provided on an optical path of the transmitted recording laser light, and a first acousto-optical element is controlled by controlling the first feedback system. The light intensity and the irradiation position of the recording laser beam passing through the recording laser beam 13 are corrected, and a second acousto-optic device 18 is disposed on the second optical path of the recording laser beam. A second feedback system comprising a second photodetector 20 and a second controller 21 on the optical path of the recording laser light transmitted through
Since the control of the second feedback system corrects the light intensity and the irradiation position of the recording laser light transmitted through the second acousto-optic element 18, the resist layer corresponds to the pits and grooves of the optical disk. Two types of latent images having different patterns can be simultaneously formed with high accuracy.

The exposure apparatus 10 includes first and second exposure apparatuses.
The acousto-optic devices 13 and 18 have a function of correcting the light intensity and irradiation position of the recording laser light and a function of performing intensity modulation in accordance with the recording signal. It is possible to form an accurate latent image on the resist layer.

Although the basic configuration of the exposure apparatus 10 has been described above, the exposure apparatus 10 may be configured, for example, to collect a recording laser beam or to collimate a recording laser beam according to the purpose of use. Various optical systems such as a collimator lens for converting light, a polarization optical system for changing the polarization state of the recording laser light, and a folding mirror for bending the optical path of the laser light may be appropriately provided.

In the above, the first and second acousto-optical elements 13 and 18 have both the function of correcting the light intensity and the irradiation position of the recording laser light and the function of modulating the intensity of the recording laser light. Although the example provided is described, the exposure apparatus according to the present invention is not limited to this example, and the first and second exposure apparatuses correct the light intensity and irradiation position of the recording laser light.
In addition to the acousto-optical elements 13 and 18 described above, other optical elements that perform intensity modulation of the recording laser light may be provided.

(Third Embodiment) Next, a description will be given of a third embodiment of the exposure apparatus according to the present invention.

The exposure apparatus according to the third embodiment is characterized in that an acousto-optic element and a feedback system on two separated optical paths are provided on a feed platen, respectively.

That is, in the exposure apparatus 30 of the third embodiment, as shown in FIG. 3, the first and second recording laser beams emitted from the light source 31 and separated by the first half mirror 32 are used. Each optical element disposed on the second optical path is supported by the feed platen 45.

More specifically, on the first optical path of the recording laser light reflected by the first half mirror 32, a first acousto-optical element 33 is provided.
A second acousto-optic element 35 is disposed on a second optical path of the recording laser light transmitted through the first reflecting mirror 34 and reflected by the first folding mirror 34.

A first polarizing beam splitter 36 is provided on a first optical path of the recording laser beam transmitted through the first acousto-optic element 33. The first polarization beam splitter 36 also receives the recording laser beam of the second optical path that has passed through the second acousto-optic device 35 and has been reflected by the second folding mirror 37. Then, the recording laser light of the first optical path transmitted through the first acousto-optical element 33 transmits the first polarization beam splitter 36 and is recorded on the second optical path reflected by the second folding mirror 37. Is reflected by the first polarizing beam splitter 36, so that the recording laser light in the first optical path and the recording laser light in the second optical path draw close trajectories parallel to each other. Become.

A second half mirror 38 is provided on the optical path of the recording laser beam transmitted through the first polarizing beam splitter 36 or reflected by the first polarizing beam splitter 36. A second beam splitter 39 is disposed on the optical path of the recording laser light reflected by the second half mirror 38.
The second beam splitter 39 transmits the recording laser light in the first optical path and reflects the recording laser light in the second optical path.

The first photodetector 40 is provided on the first optical path of the recording laser light transmitted through the second beam splitter 39.
Are arranged. Then, a first controller 41 is connected between the first photodetector 40 and the first acousto-optical element 33, and the first photodetector 40 and the first controller 41 A first feedback system is configured.

A second photodetector 42 is provided on the second optical path of the recording laser light reflected by the second beam splitter 39. A second controller 43 is connected between the second photodetector 42 and the second acousto-optical element 35, and the second photodetector 4
2 and the second controller 43 form a second feedback system.

On the other hand, an objective lens 44 is provided on the first optical path and the second optical path of the recording laser beam transmitted through the second half mirror 38.

Then, in the exposure apparatus 30 of the third embodiment, the first and second acousto-optical elements 33, 3
5. First and second feedback systems, first and second polarizing beam splitters 36 and 39, second folding mirror 37, second half mirror 38, and objective lens 44
Is provided on a feed platen 45 which is movable in the radial direction of the glass substrate on which the resist layer is formed.

The glass substrate on which the resist layer has been formed is chucked on an air spindle that rotates with high rotational accuracy.

The optical elements constituting the exposure apparatus 30 of the third embodiment are the same as those of the exposure apparatus 1 of the first embodiment.
Further, since these are the same as the respective optical elements constituting the exposure apparatus 10 of the second embodiment, detailed description will be omitted. Also,
In the exposure apparatus 30 of the third embodiment, the first
The acousto-optic element 33 and the second acousto-optic element 35 have both a function of correcting the light intensity and exposure intensity of the recording laser light and a function of modulating the intensity of the recording laser light.

When the exposure is performed by the exposure apparatus 30 configured as described above, first, the glass substrate on which the resist layer is formed is chucked by an air spindle (not shown), and the light source 31 forms the glass substrate on the glass substrate. The recording laser light having the photosensitive wavelength of the resist layer thus emitted is emitted.

The optical path of the recording laser light emitted from the light source 31 is separated by the first half mirror 32.
The recording laser light reflected by the first half mirror 32 enters the first acousto-optic element 33. Then, the recording laser light incident on the first acousto-optic element 33 is intensity-modulated by the first acousto-optic element 33 in accordance with a recording signal.

On the other hand, the recording laser light transmitted through the first half mirror 32 is reflected by the first folding mirror 34 and enters the second acousto-optical element 35. And
The recording laser light incident on the second acousto-optic element 35 is intensity-modulated by the second acousto-optic element 35 according to a recording signal.

The recording laser light of the first optical path, the intensity of which has been modulated by the first acousto-optic element 33, passes through the first polarizing beam splitter 36, enters the second half mirror 38, and The recording laser light of the second optical path, the intensity of which is modulated by the second acousto-optic element 35, is reflected by the second folding mirror 37, further reflected by the first polarization beam splitter 36, and is reflected by the second half mirror 38.
Incident on.

The recording laser beam on the first optical path reflected by the second half mirror 38 passes through the second polarizing beam splitter 39 and is received by the first photodetector 40. Then, the recording laser light of the first optical path received by the first photodetector 40 is applied to the first photodetector 40.
Is converted into an electric signal by the first controller 41
Supplied to

The first controller 41 determines the light intensity and the deviation of the diffraction angle of the first-order diffracted light emitted from the first acousto-optic element 33 based on the light receiving signal supplied from the first photodetector 40. Is detected. Then, the first controller 41 controls the first order so that the light intensity and the diffraction angle of the first-order diffracted light emitted from the first acousto-optic element 33 become predetermined values.
The intensity and frequency of the carrier supplied to the acousto-optic device 33 are changed.

On the other hand, the recording laser light of the second optical path reflected by the second half mirror 38 is reflected by the second polarizing beam splitter 39 and is reflected by the second photodetector 42.
Received from two. Then, the recording laser light in the second optical path received by the second photodetector 42 is converted into an electric signal by the second photodetector 42 and supplied to the second controller 43.

The second controller 43 controls the light intensity and the deviation of the diffraction angle of the first-order diffracted light emitted from the second acousto-optic device 35 based on the light receiving signal supplied from the second photodetector 42. Is detected. Then, the second controller 43 sets the second intensity so that the light intensity and the diffraction angle of the first-order diffracted light emitted from the second acousto-optic element 35 become predetermined values.
The intensity and frequency of the carrier supplied to the acousto-optic device 35 are changed.

As described above, in the exposure apparatus 30, the first photodetector 40 and the second controller 41 use
Feedback control is performed on the first acousto-optical element 33, and the second photodetector 42 and the second controller 43 are controlled.
By performing feedback control on the second acousto-optic element 35, the first-order diffracted light emitted from the first and second acousto-optic elements 33, 35, ie, the light intensity and emission angle of the recording laser light Is corrected. Therefore, according to the exposure apparatus 30, variation in the diameter of the exposure pattern and displacement of the exposure position are suppressed, and a precise latent image can be formed on the resist layer.

The recording laser beams of the first and second optical paths transmitted through the second half mirror 38 are both
And is condensed by the objective lens 44, and is simultaneously irradiated on the resist layer formed on the glass substrate.

As a result, latent images of two different patterns are formed on the resist layer with high accuracy.

As described above, according to the exposure apparatus 30, the first acousto-optical element 33 is provided on the first optical path of the recording laser light, and the first acousto-optical element 33 is A first feedback system including a first photodetector 40 and a first controller 41 is disposed on an optical path of the transmitted recording laser light, and a first acousto-optical element is controlled by controlling the first feedback system. The light intensity and the irradiation position of the recording laser light transmitted through the recording laser beam 33 are corrected, and the second acousto-optic element 35 is disposed on the second optical path of the recording laser light. A second feedback system comprising a second photodetector 42 and a second controller 43 on the optical path of the recording laser light transmitted through
The control of the second feedback system corrects the light intensity and the irradiation position of the recording laser beam transmitted through the second acousto-optic element 43, so that the resist layer corresponds to the pits and grooves of the optical disc. Two types of latent images having different patterns can be simultaneously formed with high accuracy.

The exposure apparatus 10 includes first and second exposure apparatuses.
The acousto-optic devices 33 and 35 have a function of correcting the light intensity and irradiation position of the recording laser light, and a function of performing intensity modulation in accordance with the recording signal. It is possible to form an accurate latent image on the resist layer.

The exposure apparatus 10 includes a first and second acousto-optical elements 33 and 35 on a feed platen 45 which is moved in the radial direction of a glass substrate on which a resist layer is formed.
First and second feedback systems, first and second polarization beam splitters 36 and 39, second folding mirror 3
7. Since the second half mirror 38 and the objective lens 44 are provided to correct the light intensity and the irradiation position of the recording laser light on the feed platen 45, the feed plate 45 is fed. Correction can be performed for an operation error and the like, and feedback control can be performed at a position close to the objective lens 44, so that the light intensity and irradiation position of the recording laser light can be corrected with higher accuracy. be able to.

Although the basic configuration of the exposure apparatus 30 has been described above, the exposure apparatus 30 may be, for example, a condensing lens for condensing the recording laser light or a collimating laser beam depending on the purpose of use. Various optical systems such as a collimator lens for converting light, a polarization optical system for changing the polarization state of the recording laser light, and a folding mirror for bending the optical path of the laser light may be appropriately provided.

In the above description, the first and second acousto-optical elements 33 and 35 have both the function of correcting the light intensity and irradiation position of the recording laser light and the function of modulating the intensity of the recording laser light. Although the example provided is described, the exposure apparatus according to the present invention is not limited to this example, and the first and second exposure apparatuses correct the light intensity and irradiation position of the recording laser light.
In addition to the acousto-optic elements 33 and 35 described above, other optical elements that perform intensity modulation of the recording laser beam may be provided.

[0123]

The exposure apparatus according to the present invention detects an acousto-optic element for correcting the light intensity and irradiation position of a laser beam emitted from a light source, and detects a part of the laser beam transmitted through the acousto-optic element. A feedback system for controlling the acousto-optic element so that the light intensity and the irradiation position of the laser light become desired; and correcting both the light intensity and the irradiation position of the laser light emitted from the light source. Therefore, accurate exposure can be performed.

Further, in this exposure apparatus, if the intensity of the laser beam is modulated in accordance with the recording signal by the acousto-optic device for correcting the light intensity and the irradiation position of the laser beam,
A latent image of a desired pattern can be formed with high accuracy while simplifying the configuration.

Further, in this exposure apparatus, the acousto-optic element and the feedback system are excreted on a feed platen that movably supports an objective lens that collects laser light and irradiates the recording medium with the laser light. In addition, it is possible to correct errors in the feeding operation of the feed platen and the like, and the acousto-optic element and the feedback system are provided at a position close to the objective lens, so that the laser light can be more precisely emitted. The intensity and the irradiation position can be corrected.

Further, in the exposure method according to the present invention, an acousto-optic device and a feedback system for detecting a part of the laser beam transmitted through the acousto-optic device are provided on the optical path of the laser beam emitted from the light source. The acousto-optic device is controlled based on a part of the laser light detected by the feedback system to correct the light intensity and the irradiation position of the laser light. Corrected exposure can be performed with high accuracy.

In this exposure method, a laser beam intensity modulation is performed by using an acousto-optic device that corrects the light intensity and irradiation position of the laser beam, thereby easily forming a latent image of a desired pattern with high accuracy. can do.

In this exposure method, the acousto-optic element and the feedback system are provided on a feed platen that movably supports an objective lens that collects laser light and irradiates the object with a laser beam. By correcting the light intensity and the irradiation position of the laser beam on the board, it is possible to correct errors in the feed operation of the feed platen, etc. Is provided at a position close to the objective lens, the light intensity and the irradiation position of the laser beam can be corrected with higher accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a schematic configuration of an exposure apparatus according to the present invention.

FIG. 2 is a configuration diagram showing a schematic configuration of another exposure apparatus according to the present invention.

FIG. 3 is a configuration diagram showing a schematic configuration of still another exposure apparatus according to the present invention.

FIG. 4 is a configuration diagram showing a schematic configuration of a conventional exposure apparatus.

[Explanation of symbols]

1,10,30 exposure apparatus, 2,11,31 light source,
3,13,18,33,35 Acousto-optic element, 5,1
5, 20, 40, 42 photodetector, 8, 16, 21, 4
1,43 controller

Claims (10)

[Claims] 1. An exposure apparatus for irradiating a laser beam emitted from a light source to a photosensitive material layer to form a latent image having a predetermined pattern on the photosensitive material layer, wherein the light intensity and the irradiation position of the laser light are corrected. An acousto-optic element, detecting a part of the laser light transmitted through the acousto-optic element,
An exposure apparatus comprising: a feedback system that controls the acousto-optic element so that the light intensity and irradiation position of the laser light become desired. 2. The feedback system controls the intensity of the carrier of the acousto-optic element and the frequency of the carrier of the acousto-optic element based on a part of the detected laser light. 2. An irradiation position of the laser light is corrected by controlling the intensity of the carrier by controlling the carrier intensity by controlling the frequency of the carrier by the feedback system. Exposure apparatus according to the above. 3. The exposure apparatus according to claim 1, wherein the acousto-optic element performs intensity modulation of the laser light according to a recording signal. 4. An objective lens for condensing the laser beam and irradiating the recording medium, and a feed platen for movably supporting the objective lens, wherein the acousto-optic element and the feedback system are: 2. An exposure apparatus according to claim 1, wherein said exposure apparatus is provided on said feed platen. 5. The exposure apparatus according to claim 1, further comprising an optical path separating unit that separates an optical path of the laser light emitted from the light source into a plurality of optical paths. 6. An exposure method for irradiating a laser beam emitted from a light source to a photosensitive material layer to form a latent image having a predetermined pattern on the photosensitive material layer. A feedback system for detecting a part of the laser light transmitted through the acousto-optic element; controlling the acousto-optic element based on a part of the laser light detected by the feedback system; And an irradiation position. 7. The intensity of the carrier of the acousto-optic element and the frequency of the carrier of the acousto-optic element are controlled based on a part of the laser beam detected by the feedback system, and the intensity of the carrier of the acousto-optic element is controlled. 7. The exposure method according to claim 6, wherein the light intensity of the laser light is corrected by controlling, and the irradiation position of the laser light is corrected by controlling a frequency of a carrier of the acousto-optic element. 8. An exposure method according to claim 6, wherein said laser light is intensity-modulated according to a recording signal using said acousto-optic element. 9. An acousto-optic device and the feedback system are provided on a feed plate that movably supports an objective lens that collects the laser beam and irradiates the object with the laser beam, and the feed plate. 7. The exposure method according to claim 6, wherein the light intensity of the laser light and the exposure position are corrected. 10. The exposure method according to claim 6, wherein an optical path of the laser light emitted from the light source is divided into a plurality of paths, and exposure is performed by each of the separated laser lights.