JPH10161126A - Method for forming oriented film and exposing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute the batch exposure of polarization in a wide area by originating light from a light source to a reflection-type diffracting grid which mainly reflects first poralization so as to permit reflection light by means of the diffracting grid and originating reflection light to a material. SOLUTION: At least one of first reflecting means 15 or the second reflecting means 21 is constituted of the reflection-type diffracting grid which mainly reflects first polarization. The first reflecting means 15 is arranged opposite to an elliptical recessed surface mirror 13 by a prescribed angle. The first reflecting means 15 is one kind of reflecting means for introducing light from the light source 11 or the elliptically recessed surface mirror 13 to an exposed object 25 and is provided with a function for reflecting light from the light source 11 to the direction of the second reflecting means 21. Since at least one reflecting means 15 within the more than one reflection means 15 and 21 is constituted by the reflection-type diffracting grid which mainly reflects first polarization, the wide area is exposed by polarization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method for forming an alignment film for aligning liquid crystal molecules, and an exposure apparatus suitable for use in the method.

[0002]

2. Description of the Related Art A typical method for forming an alignment film is a method of rubbing a substrate or a material for forming an alignment film formed on the substrate in a predetermined direction with a cloth or the like (so-called rubbing method).
However, the rubbing method requires a subsequent cleaning step,
There is a problem that it is difficult to mix minute regions having different orientations on the substrate.

As a technology that can be expected to solve these problems, for example, Reference I (Mol. Cryst. Liq. Cryst. 1994, Vol. 25)
1, pp. 191-208, especially pp. 191, 195-198). This is a technique using a material that, when irradiated with polarized light, has a portion that functions as an alignment film for liquid crystal.

[0004] In detail, certain polymers (pr.
A film of an oprietary polymer) is formed on a substrate, and the film is irradiated with a laser beam, which is a polarized laser beam (hereinafter, a polarized laser beam), while scanning the film. A liquid crystal cell is formed using the substrate processed as described above. Then, it is said that the liquid crystal exhibits the same tilt angle as that of the rubbing method (see p. 198 of Document I).
Table 3).

[0005]

However, in the case of the technique disclosed in Document I, it is necessary to scan a certain polymer with a polarized laser beam. Since the laser beam is scanned, the time for forming the alignment film becomes long.

[0006] The reason for using a polarized laser beam in the prior art is that there is currently no technique that can collectively expose polarized light over a wide area.

A new method capable of easily forming an alignment film and a novel exposure apparatus capable of collectively exposing polarized light to a wide area are desired.

[0008]

Accordingly, the inventor of the present application has made various studies. As a result, certain types of diffraction gratings, when irradiated with light, have a first polarization (S
(Polarized light or P-polarized light). Then, it was thought that the reflected light could be used as a polarized light required when a material that becomes a film that functions as an alignment film with respect to liquid crystal when irradiated with polarized light is formed into an alignment film.

Therefore, according to the method for forming an alignment film of the present invention, a material whose irradiated portion exhibits a function as an alignment film for liquid crystal when irradiated with polarized light is irradiated with the polarized light to form an alignment film. In the method, a light from a light source is applied to a reflective diffraction grating that mainly reflects the first polarized light to generate light reflected by the diffraction grating, and the reflected light is applied to the material. .

[0010] In the present invention, mainly reflecting the first polarized light means that when only the first polarized light is reflected,
The case where the second polarized light is reflected to some extent but mainly reflected the first polarized light is meant to include both cases.

According to the method for forming an alignment film of the present invention, the reflected light reflected from a predetermined diffraction grating is used as polarized light for forming an alignment film.

The reflected light from a predetermined diffraction grating is light whose exposure range is sufficiently wider than that of a laser beam. As a result, the area in which the polarized light can be collectively exposed is increased, so that the time for forming the alignment film can be reduced.

The fact that batch exposure is possible means that
It also means that selective exposure through a photomask is possible. Then, for example, when sequentially exposing a plurality of exposure regions adjacent to each other with a very small area, exposure can be performed sequentially by changing the polarization direction of the exposure light for each exposure region as needed. Therefore, a state where two or more polarization directions are mixed in a certain display region of a liquid crystal cell (so-called multi-domain).
Can be easily generated.

Here, as a means for generating polarized light, there is a transmission type polarizing means. However, a transmission type polarizing means having a relatively large area is generally a polymer film having dichroism. It is considered that such a polarization means is liable to cause light degradation, for example. On the other hand, in the forming method of the present invention, polarized light is generated by the reflection type diffraction grating. Since this reflection type diffraction grating basically has a large number of grooves formed on a base so that these grooves are arranged at a predetermined pitch, it is easy to form a strong material. Therefore, in the present invention, it is considered that light deterioration of the polarizing means (reflection type diffraction grating) is unlikely to occur.

In addition, transmission type polarizing means for ultraviolet light are difficult to obtain, whereas reflection type diffraction gratings have realized a diffraction grating that gives polarized light to ultraviolet light (for example, Milton Roy (MILTON RO)
Y) A diffraction grating manufactured by the company. Details will be described later. ). On the other hand, there is a material that is sensitive to ultraviolet light when its part is irradiated with polarized light so that the portion exhibits a function as an alignment film for liquid crystal. Moreover, in constructing a new exposure apparatus for forming an alignment film (the invention of an exposure apparatus described later), considering that the technology cultivated in the exposure apparatus for a semiconductor device or a liquid crystal device is used, It is considered that a light source having a high track record in these conventional exposure apparatuses, that is, a light source mainly emitting ultraviolet light, such as an ultra-high pressure mercury lamp, is used. From these facts, it is considered preferable to use a reflection type diffraction grating.

According to the invention of the exposure apparatus of the present application, the exposure apparatus includes a light source and one or more reflecting means for guiding light emitted from the light source to an object to be exposed.
At least one reflecting means of the above reflecting means,
It is characterized by comprising a reflection type diffraction grating which mainly reflects the first polarized light.

According to the invention of the exposure apparatus (hereinafter, also referred to as a first invention of the exposure apparatus), an exposure apparatus capable of collectively exposing polarized light to a wide exposure area is realized.

Here, as means for generating polarized light, there is a transmission type polarizing means. However, a transmission type polarizing means having a relatively large area is generally a polymer film having dichroism. It is considered that such a polarization means is liable to cause light degradation, for example. On the other hand, the first invention of this exposure apparatus includes a reflection type diffraction grating as means for generating polarized light. Since this reflection type diffraction grating basically has a large number of grooves formed on a base so that these grooves are arranged at a predetermined pitch, it is easy to form a strong material. Therefore, in the first aspect of the exposure apparatus, it is considered that light deterioration of the polarizing means (reflection type diffraction grating) hardly occurs.
Therefore, it is considered that an exposure apparatus with high durability can be realized.

In addition, transmission type polarizing means for ultraviolet light are difficult to obtain, whereas a reflection type diffraction grating has realized a diffraction grating that gives polarized light to ultraviolet light (for example, Milton Roy (MILTON RO)
Y) A diffraction grating manufactured by the company. Details will be described later. ). On the other hand, there is a material that is sensitive to ultraviolet light when its part is irradiated with polarized light so that the portion exhibits a function as an alignment film for liquid crystal. In addition, in constructing a new exposure apparatus for forming an alignment film, considering that the technology cultivated in the exposure apparatus for a semiconductor device or a liquid crystal device is used, as a light source, these conventional exposure apparatuses have a high light source. It is preferable to use a light source that has a proven track record, that is, a light source that mainly emits ultraviolet light, such as a high-pressure mercury lamp. From this, it is considered preferable to realize the exposure apparatus using the reflection type diffraction grating.

A conventional typical exposure apparatus has a large number of individual lenses for guiding light from a light source to an object to be exposed, and outputs light so that the lights exiting the individual lenses overlap each other. And a light source. When the first aspect of the exposure apparatus is applied to such an exposure apparatus, the first polarized light in the light from the light source is mainly reflected between the light source and the multi-lens type lens. It is preferable to provide a reflection type diffraction grating for guiding the light to the multi-lens.

The multi-lens type lens here is a known optical component called an integrator or a fly's eye lens. Typically, it is a lens group combining a plurality of fly-eye lenses and the like. This is an optical component for uniformly irradiating light from a light source to an object to be exposed.

In this preferred embodiment, the reflection type diffraction grating which mainly reflects the first polarized light is located on the input side of the multi-lens type lens. Then, the diffraction grating does not directly affect light emitted from the multi-lens. Therefore, there is little danger of impairing the above-mentioned function of the multi-lens type lens. In general, the area of the reflection means itself can be reduced when the reflection means is provided on the light source side. This means that the area of the diffraction grating itself can be reduced. It is considered that such a diffraction grating can be easily manufactured and the price can be reduced.

This application also claims the invention of the following exposure apparatus (hereinafter, also referred to as a second invention of the exposure apparatus).

That is, a multi-lens type lens having a large number of individual lenses for guiding the light of the light source toward the object to be exposed, and outputting light so that the lights exiting the individual lenses overlap each other, and the light source. In the above exposure apparatus, an exposure apparatus having a transmission type polarizing means mainly transmitting the first polarized light between the light source and the multi-lens type lens is claimed.

In the present invention, transmitting mainly the first polarized light means that when transmitting only the first polarized light,
This means that the second polarized light is transmitted to some extent but the first polarized light is mainly transmitted (the same applies hereinafter).

In the second aspect of this exposure apparatus, a transmission type polarizing means is used. However, since it is provided on the input side of the multi-lens type lens, it can be relatively small. Therefore, it is considered that a polarizing means which is relatively hard to cause light degradation even in a transmission type can be used. For example, a polarizing means using a crystal is used.

Furthermore, since the transmission type polarizing means is provided on the input side of the multi-lens type lens, the light emitted from the multi-lens type lens is not directly affected by the transmission type polarizing means. Therefore, there is little danger of impairing the function of the multi-lens.

In implementing the second aspect of the exposure apparatus, the transmission type polarizing means may be a polarizing means common to all the individual lenses included in the multi-lens type lens. It is preferable to form a polarizing element group in which the polarizing elements of the molds are configured to face each other. In this case, the individual polarizing elements need only be small. Although it is difficult to obtain a large-sized and high-performance transmission-type polarizing element, a small-sized transmission-type polarizing element with good performance is easily available. This preferred example is considered to enable the realization of an exposure apparatus using a transmission type polarizing means having good performance.

In practicing the first and second aspects of the exposure apparatus, the light source provided in the exposure apparatus may be any light source that emits light having a wavelength required by the object to be exposed. However, the light source is preferably a light source mainly emitting ultraviolet light. The reason is that: It is expected that the material that will be irradiated with polarized light, the part of which exhibits a function as an alignment film with respect to the liquid crystal, will be mainly sensitive to ultraviolet light. This is because it is preferable to use an ultraviolet light source, which has a high track record in conventional exposure apparatuses, as a light source, in view of utilizing the technology cultivated in the apparatus. Examples of the ultraviolet light source include a discharge lamp, specifically, an ultra-high pressure mercury lamp, a high pressure mercury lamp, and a Mercury xenon lamp.

[0030]

Embodiments of the present invention will be described below with reference to the drawings. However, the drawings used in the description are merely schematic representations so that the present invention can be understood. In the drawings used for the description, the same components are denoted by the same reference numerals, and the duplicate description thereof may be omitted.

1. Description of Reflection-Type Diffraction Grating and Description of Method for Forming Alignment Film First, a description will be given of a reflection-type diffraction grating used in the invention of the method for forming an alignment film and the first invention of the exposure apparatus of this application.

As a reflection type diffraction grating that can be used in these inventions, for example, Milton Roy (MI
LTON ROY). Specifically, there can be mentioned a diffraction grating called serial number 5185-1-1-1 and a diffraction grating called serial number 5188 / FZ10 described in the catalog of the company.

It is described in the catalog that the diffraction grating referred to as serial number 5185-1-1-1 is a diffraction grating having grooves at a density of 2400 lines / mm.
On the other hand, the catalog describes that a diffraction grating referred to as serial number 5188 / FZ10 is a diffraction grating having grooves at a density of 3600 lines / mm.

The reflection characteristic of the former diffraction grating is as shown in FIG. The reflection characteristics of the latter diffraction grating are as shown in FIG.

FIGS. 1 and 2 show the reflection characteristics of the diffraction grating quoted from the above catalog. FIG. 7 is a diagram showing the wavelength dependence of the reflectance of each of S-polarized light and P-polarized light, with the wavelength (μm) on the horizontal axis and the reflectance (%) on the vertical axis. However, the reflection characteristics when the light irradiation target is aluminum are also shown as a comparative example.

1 and 2, S represents the wavelength dependence of the reflectance of S-polarized light at the diffraction grating, and P represents the wavelength dependence of the reflectance of P-polarized light at the diffraction grating. AL in FIGS. 1 and 2
Is a comparative example (reflection characteristics for aluminum) described above.

From FIGS. 1 and 2, it can be understood that the above-mentioned diffraction grating can be a reflection type diffraction grating that mainly reflects the first polarized light (S-polarized light or P-polarized light) according to the wavelength of the incident light.

Specifically, in the case of the former diffraction grating, as can be seen from FIG. 1, the reflectance for P-polarized light near the wavelength of 0.3 μm is about 90%, whereas the reflectance for S-polarized light near the same wavelength is about 90%. Is only about 30%. Furthermore, while the reflectance for P-polarized light near the wavelength of 0.5 to 0.7 μm is only about 35 to 10%, the reflectance for S-polarized light near the same wavelength is 90% or more.

In the case of the latter diffraction grating, as can be seen from FIG. 2, the reflectance for P-polarized light near the wavelength of 0.25 μm is about 80%, whereas the reflectance for S-polarized light near the same wavelength is about 80%. Only a few percent. Further, the reflectivity for P-polarized light around a wavelength of 0.4 to 0.5 μm is 30.
While the reflectance is only about 10%, the reflectance for S-polarized light near the same wavelength is 90% or more.

When the diffraction grating is irradiated with light from a light source, for example, an ultraviolet light source such as an ultra-high pressure mercury lamp, and the reflected light is generated by the diffraction grating, the reflected light mainly has the first polarization. It is thought that it becomes light.

The light from the light source is preferably irradiated through a suitable filter. This is because light having a wavelength having a large reflectance ratio between the P-polarized light and the S-polarized light can be selectively applied to the diffraction grating.

On the other hand, it is considered that the alignment film may be formed as follows, for example. On a suitable substrate, for example, Reference I (Mol. Cryst. Liq. Cryst. 1994, Vol. 251, pp. 191-208)
Certain of the polymers disclosed in US Pat.
polymer). The film is irradiated with light reflected from the diffraction grating. Since the reflected light is light mainly having the first polarized light, it is considered that a portion of the film irradiated with the reflected light becomes an alignment film.

When irradiating the reflected light, it is possible to irradiate through a photomask having a predetermined portion as a light transmitting window. In this case, selective exposure can be easily performed.

According to this method for forming an alignment film, since the polarized light can be applied to a wide area at a time, the time for forming the alignment film can be shortened as compared with the case where a laser beam is used.

2. Description of First Invention of Exposure Apparatus Next, a first invention of an exposure apparatus will be described. Here, an example in which the first invention of the exposure apparatus is applied to a known exposure apparatus for manufacturing a liquid crystal display device will be described.

2-1. First Embodiment FIG. 3 is a view showing one example of a typical exposure apparatus.
Document II ("Electronic Materials", published by the Industrial Research Council, July 1995)
FIG. 95 is a drawing citing the exposure apparatus disclosed in the monthly special volume, page 95). This is an apparatus described as a proximity exposure type exposure apparatus in Document II.

This exposure apparatus comprises an extra-high pressure mercury lamp 11 as a light source, an elliptical concave mirror 13, a first reflecting means 15,
A collimator 17, an integrator (flying eye lens) 19 as a multi-lens type lens, and a second reflecting means 21
And a condenser lens 23. Note that FIG.
Reference numeral 25 indicates an object to be exposed.

The elliptical concave mirror 13 is provided near the light source 11. The elliptical concave mirror 13 has a function of collecting light from the ultra-high pressure mercury lamp 11 in the direction of the first reflecting means 15.

The first reflecting means 15 is disposed so as to face the elliptical concave mirror 13 at a predetermined angle. This first
The reflection means 15 is one of reflection means for guiding light from the light source 11 and the elliptical concave boundary 13 to the object 25 to be exposed. Here, the light from the light source 11 is directed toward the second reflection means 21. Has the function of reflecting.

Collimator 17 and multi-lens 19
Is provided between the first reflecting means 15 and the second reflecting means 21 in the order of the collimator 17 and the multi-lens 19 from the first reflecting means 15 side.

As described above, the multi-lens type lens 19 has a large number of individual lenses and has a function of outputting light so that the lights exiting the individual lenses overlap each other (see FIG. 8). When the multi-lens lens 19 is used, the light from the light source 11 can be evenly applied to the object 25 to be exposed.

The second reflecting means 21 has a function of guiding light emitted from the light source 11 and passing through the first reflecting means 15 and the like to the object 25 to be exposed.

The condenser lens 23 is connected to the second reflecting means 2
1 and the object 25 to be exposed.

In the case of this exposure apparatus, the first reflecting means 15
At least one of the second reflection means 21 and the second reflection means 21 is preferably constituted by a reflection type diffraction grating mainly reflecting the first polarized light, for example, the diffraction grating described with reference to FIG. 1 or FIG. First reflection means 15 and second reflection means 21
Which one of them is constituted by a reflection type diffraction grating (hereinafter, also referred to as a “predetermined diffraction grating”) that mainly reflects the first polarized light can be determined by design. A specific example will be described below.

The first reflecting means 15 generally has a smaller area than the second reflecting means 21. Therefore, when the first reflecting means 15 is constituted by a predetermined diffraction grating, there is obtained an advantage that the predetermined diffraction grating has a small area. In this case, since the predetermined diffraction grating is located on the input side of the multi-lens 19, it is possible to prevent the predetermined diffraction grating from affecting the output light of the multi-lens. From these facts, it is considered that the reflecting means (here, the first reflecting means 15) located closest to the light source 11 is constituted by a predetermined diffraction grating. It is an effective method.

Here, when the first reflecting means 15 is constituted by a predetermined diffraction grating, polarized light generated by the predetermined diffraction grating reaches an object to be exposed after passing through a multi-lens lens 19 and the like. Even in this case, it has been confirmed by experiments performed by the inventor of the present application that the polarized light is preserved (for details, see the examples below).

The second reflection means 21 may be constituted by a predetermined diffraction grating. Also in this case, polarized light can be supplied to a wide area. Therefore, the idea that the reflecting means (here, the second reflecting means 21) located closest to the object 25 to be exposed is constituted by a predetermined diffraction grating is one suitable way of designing the exposure apparatus of the present invention. It can be said to be a technique.

However, when the second reflecting means 21 is constituted by a predetermined diffraction grating, the predetermined diffraction grating is located on the output side of the multi-lens type lens. Therefore, if the reflectance distribution of the predetermined diffraction grating is not good, the function of the multi-lens may be impaired. The reflection means located at a position close to the exposure object 25 generally has a large area. Then, the predetermined diffraction grating also needs to have a large area. A given diffraction grating becomes more expensive as the area becomes larger. These points are limiting factors.

Of course, both the first reflecting means 15 and the second reflecting means 21 may be constituted by a predetermined diffraction grating.

In the above description, an example in which at least one of the existing reflecting means 15 and 21 is replaced with a predetermined diffraction grating has been described. However, it is a matter of course that the idea of newly providing a reflecting means constituted by a predetermined diffraction grating at a suitable position separately from the existing reflecting means is also included in the scope of the present invention. the same).

The construction of the reflection means by a predetermined diffraction grating means a case where a diffraction grating is added, such as a case where a predetermined diffraction grating is mounted on an existing reflection means. The same in the form of).

2-2. Second Embodiment FIG. 4 is a view showing another example of a typical exposure apparatus. FIG. 2 is a drawing citing an exposure apparatus disclosed in Document II (“Electronic Materials”, published by the Industrial Research Institute, July 1995, separate volume, page 96). This is an apparatus described in Document II as an exposure apparatus using a lens stepper split exposure system.

This exposure apparatus has substantially the same configuration as that of FIG. Specifically, the ultra-high pressure mercury lamp 1
1, an elliptic concave mirror 13, a first reflecting means 15, an integrator 19 as a multi-lens lens, a second reflecting means 21, and a condenser lens 23. Further, since this device is a stepper type device, it is provided with a reticle setting table 27 and a projection lens 29.

In the case of the exposure apparatus described with reference to FIG. 4, at least one of the first and second reflecting means 15 and 21 is constituted by a predetermined diffraction grating, or a predetermined diffraction grating is used. A new reflecting means is provided at any suitable position. By doing so, the exposure apparatus of the present invention can be configured.

Which of the first and second reflecting means 15 and 21 is to be a predetermined diffraction grating may be determined based on the same concept as described for the exposure apparatus described with reference to FIG.

2-3. Third Embodiment FIG. 5 is a view showing still another example of a typical exposure apparatus. Document II ("Electronic Materials", published by the Industrial Research Institute, 1995
FIG. 97 is a drawing citing an exposure apparatus disclosed in a separate volume of July, 1997, page 97). This is an apparatus described as a mirror projection exposure apparatus in Document II.

This device includes first and second reflecting surfaces 31.
This is a device including a trapezoidal mirror 31 having a and 31b, a concave mirror 33, and a convex mirror 35. In FIG. 5, reference numeral 37 denotes a photomask setting table.

The trapezoidal mirror 31 has a first reflecting surface 31a.
Faces a light source (not shown) at a predetermined angle, and
The second reflection surface 31a is disposed so as to face the object 25 at a predetermined angle.

The concave mirror 33 is disposed so as to face the first and second reflecting surfaces 31a and 31b of the trapezoidal mirror 31.

The convex mirror 35 is connected to the trapezoidal mirror 31 and the concave boundary 3.
3 is provided. In addition, the trapezoidal mirror 31 and the concave boundary 33 are smaller lenses. Moreover, the first reflecting surface 31a, the concave boundary 33, the convex mirror 35,
The convex boundary 35 is arranged so that light travels again along the path of the concave mirror 33 and the second reflecting surface 31b.

In the case of the exposure apparatus described with reference to FIG. 5, the first reflection surface 31a of the trapezoidal mirror 31, the second reflection surface 31b of the trapezoidal mirror 31, the concave boundary 33 and the convex boundary 3
At least one of the reflecting means 5 is constituted by a predetermined diffraction grating, or a new reflecting means using a predetermined diffraction grating is provided at any suitable position. By doing so, the exposure apparatus of the present invention can be configured.

However, it is preferable that the first
Either one of the reflection surface 31a and the second reflection surface 31b is preferably formed of a predetermined diffraction grating. Although it is considered that a predetermined diffraction grating having a concave surface or a convex surface can be manufactured, a predetermined diffraction grating having a flat surface is considered to be easier and cheaper to manufacture. More preferably, it is considered that the second reflection surface 31b of the trapezoidal mirror, that is, the reflection means closest to the object to be exposed, is preferably formed of a predetermined diffraction grating. This is because it is considered that polarization in a better state is obtained.

2-4. Fourth Embodiment FIG. 6 is a view showing still another example of a typical exposure apparatus. The exposure apparatus includes a light source 11, an elliptical concave mirror 13,
It comprises a first reflecting means 15, an integrator 19 as a multi-lens type lens, and a second reflecting means 21a having a curvature. In FIG. 6, reference numeral 39 denotes a photomask. As is well known, the structure has the second reflecting means 21a having a curvature, so that the condenser lens can be omitted.

In the case of the exposure apparatus described with reference to FIG. 6, at least one of the first and second reflecting means 15 and 21a is constituted by a predetermined diffraction grating, or a predetermined diffraction grating is used. A new reflecting means is provided at any suitable position. By doing so, the exposure apparatus of the present invention can be configured.

Which of the first and second reflecting means 15 and 21a is to be a predetermined diffraction grating may be determined based on the same concept as described for the exposure apparatus described with reference to FIG.

However, in this case, for the following other reasons,
Preferably, the first reflecting means 15 is constituted by a predetermined diffraction grating. The second reflecting means 21a has a curvature. It is considered that a predetermined diffraction grating having a curvature can also be manufactured, but a predetermined flat diffraction grating is considered to be easier and cheaper to manufacture.

3. Description of Second Invention of Exposure Apparatus Next, a second invention of the exposure apparatus will be described. According to a second aspect of the present invention, there is provided an exposure apparatus including a light source and a multi-lens lens, wherein the exposure apparatus includes a transmission-type polarization unit that mainly transmits the first polarized light between the light source and the multi-lens lens. The invention is characterized by the following.

FIG. 7 shows an embodiment of the second invention of the exposure apparatus.
This will be described with reference to FIG. FIG. 7 is a diagram in which the second invention is applied to a proximity exposure type exposure apparatus disclosed in Document II ("Electronic Materials", published by the Industrial Research Institute, July 1995, separate volume, page 95). .

The exposure apparatus according to the second invention comprises an extra-high pressure mercury lamp 11 as a light source, an elliptic concave mirror 13, a first reflecting means 41, a collimator 17, an integrator 19 as a multi-lens lens, 2 reflecting means 43 and the condenser lens 23. Further, the exposure apparatus of the second aspect of the present invention
A transmission type polarization means 45 mainly transmitting the first polarized light is provided.

In the example shown in FIG. 7, the polarizing means 45 is provided between the multi-lens 19 and the collimator 17 so that the multi-lens 1
9 is provided.

Here, the ultra-high pressure mercury lamp 11, the elliptical concave mirror 1
3. First reflecting means 41, collimator 17, multi-lens 19, second reflecting means 43, and condenser lens 2
The arrangement of each of the three components is the same as the components described with reference to FIG.

In the exposure apparatus described with reference to FIG. 3, at least one of the first reflecting means 15 and the second reflecting means 21 is constituted by a predetermined diffraction grating. The first reflecting means 41 and the second reflecting means 43 are constituted by reflecting means used in a conventional exposure apparatus.

As the polarizing means 45, any suitable polarizing means can be used as long as it mainly transmits the first polarized light of the light from the light source 11. For example, a transmissive polarizing plate having an area equal to or larger than that of the multi-eye lens 19 can be used.

According to the second aspect of the exposure apparatus, the light emitted from the light source 11 is changed to linearly polarized light by the polarizing means 45. Then, the polarized light reaches the exposure object 25. Therefore, an exposure apparatus capable of performing exposure using polarized light is realized.

The polarizing means 45 may be disposed between the collimator 17 and the multi-lens 19 and on the collimator 17 side. Alternatively, it may be arranged between the first reflecting means 41 and the collimator.

The concept of the second invention of the exposure apparatus is shown in FIG.
The present invention can be applied to the exposure apparatus described with reference to FIG. In either case, the transmission type polarizing means 45 is provided at a suitable position between the multi-lens 19 and the light source 11, for example, at a position near the multi-lens 19.

In the above description, the polarizing means 45 is described as being constituted by a polarizing plate having the same area as or larger than that of the multi-lens lens 19, but the present invention is not limited to this example. FIG. 8 is a diagram for explaining another configuration example of the polarization unit 45.

As is well known, the multi-view lens 19 called an integrator or the like is a lens having a large number of individual lenses 19a and outputting light so that the lights exiting the individual lenses 19a overlap each other. . Therefore, the polarizing elements 45a are arranged to face each other directly or with a gap between the input-side end faces of the individual lenses 19a. And
The group of these polarizing elements 45a constitutes a polarizing means 45.

It is difficult to obtain a transmission type polarizing means having a large size and good characteristics. On the other hand, if it is small, it is considered that a transmission type polarizing element having good characteristics is easily available. When the polarizing means 45 is constituted by a group of the polarizing elements 45a, it is considered that a transmission type polarizing element having a small size and good characteristics can be adopted.

[0090]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following is a description of experimental results suggesting that an exposure apparatus capable of performing exposure with polarized light can be realized by using a diffraction grating that mainly reflects the first polarized light. FIG. 9 is a diagram illustrating an exposure apparatus and a measurement system used in this experiment.

The light source 11, the elliptical concave mirror 13, the first reflecting means 15, the multi-lens 19, and the second reflecting means 2
1 and an exposure apparatus having a condenser lens 23 were prepared.

However, a part of the first reflecting means 15 is made of 5185-MILTON ROY.
A diffraction grating referred to as 1-1-1 and having a size of 50 mm × 50
mm diffraction grating (having the reflection characteristics shown in Fig. 1)
Was installed. The diffraction grating was mounted such that the longitudinal direction of the groove was the P direction in FIG.

Further, a region (indicated by Q in FIG. 9) of the first reflection means 15 which was not covered by the diffraction grating was covered with aluminum (not shown). This is to prevent the reflected light from being generated from the region Q of the first reflecting means 15 that was not covered by the diffraction grating.

A light receiving element 51 was installed at a place where an object to be exposed was to be placed, and an analyzer 53 was installed slightly above the light receiving element 51. In FIG. 9, reference numeral 55 denotes a shutter mechanism for blocking light from the light source as necessary.

An ultra-high pressure mercury lamp having an output of 250 W was used as the light source 11. Further, since there was no ultraviolet light here as the light receiving element 51 and the analyzer 53, a light receiving element having a main sensitivity at a wavelength of 436 nm and an analyzer capable of mainly examining polarized light near the wavelength of 436 nm were used. .

The light intensity detected by the light receiving element when the polarization direction of the polarization generated by the first reflection means 15 (predetermined diffraction grating) is parallel to the analyzer 53 (first state). Was considered 100. Then, when the analyzer 53 was rotated 90 degrees with respect to the first state, the light intensity detected by the light receiving element 51 was reduced to 15.

A similar experiment was performed by moving the light receiving element 51 and the analyzer 53 to a plurality of different positions in the exposure area, respectively, and the same result as described above was obtained.

As is clear from this experiment, if the first reflection means 15 is constituted by a predetermined diffraction grating, polarized light can be obtained, and this polarized light is preserved even if a multi-lens lens or the like is present in the middle. You can see that Further, it can be seen that uniform polarization can be obtained over the entire exposure region.

[0099]

As is clear from the above description, according to the method for forming an alignment film of the present application, light from a light source is applied to a reflection type diffraction grating that mainly reflects the first polarized light. And irradiates the material with the polarized light, the portion of which exhibits a function as an alignment film for the liquid crystal. Therefore, compared with the case where the polarized laser beam is scanned on the material, the polarized light can be collectively applied to a wider area. Therefore, it is considered that the alignment film can be formed more efficiently.

According to a first aspect of the exposure apparatus of the present invention, there is provided an exposure apparatus comprising a light source and one or more reflecting means for guiding light emitted from the light source to an object to be exposed. At least one of the reflection means is constituted by a reflection type diffraction grating that mainly reflects the first polarized light. Therefore, an exposure apparatus capable of exposing a wide area with polarized light can be realized.

According to the second aspect of the exposure apparatus of the present invention, in an exposure apparatus including a light source and a multi-lens lens such as a fly-eye lens, a light source and a multi-lens lens are interposed between the light source and the multi-lens. A transmission type polarizing means mainly transmitting one polarized light is provided. Therefore, an exposure apparatus capable of exposing a wide area with polarized light can be realized.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram (part 1) of a reflection type diffraction grating that mainly reflects a first polarized light, and is a diagram illustrating reflection characteristics.

FIG. 2 is an explanatory diagram (part 2) of a reflection type diffraction grating that mainly reflects a second polarized light, and is a diagram illustrating reflection characteristics.

FIG. 3 is an explanatory diagram of a first embodiment of the first invention of the exposure apparatus.

FIG. 4 is an explanatory diagram of a second embodiment of the first invention of the exposure apparatus.

FIG. 5 is an explanatory view of a third embodiment of the first invention of the exposure apparatus.

FIG. 6 is an explanatory view of a fourth embodiment of the first invention of the exposure apparatus.

FIG. 7 is an explanatory view of an exposure apparatus according to a second embodiment of the present invention.

FIG. 8 is an explanatory view of a main part of another embodiment of the exposure apparatus of the second invention.

FIG. 9 is an explanatory diagram of the embodiment, and is a diagram illustrating an exposure apparatus and a measurement system used in an experiment.

[Explanation of symbols]

11: light source (for example, ultra-high pressure mercury lamp) 13: elliptical concave mirror 15: first reflecting means (diffraction grating mainly reflecting first polarized light) 17: collimator 19: multi-lens 19a: individual lens 21: second Reflecting means 23: Condenser lens 25: Object to be exposed 45: Polarizing means mainly transmitting first polarized light 45a: Polarizing element

Claims (6)

[Claims] 1. A method for forming an alignment film by irradiating a polarized light to a material whose portion shows a function as an alignment film with respect to liquid crystal when irradiated with polarized light, wherein the first polarized light is mainly reflected. A method for forming an alignment film, comprising: irradiating light from a light source to a reflection type diffraction grating to generate light reflected by the diffraction grating; and irradiating the material with the reflected light. 2. An exposure apparatus comprising: a light source; and one or more reflecting means for guiding light emitted from the light source to an object to be exposed, wherein at least one of the one or more reflecting means is a An exposure apparatus comprising a reflection type diffraction grating that mainly reflects one polarized light. 3. A multi-lens type lens having a large number of individual lenses for guiding light from a light source toward an object to be exposed, and outputting light so that light emitted from each individual lens overlaps each other, and the light source. An exposure apparatus, further comprising: a reflective diffraction grating between the light source and the multi-lens lens, which mainly reflects the first polarized light in the light from the light source and guides the first polarized light to the multi-lens lens. An exposure apparatus characterized in that: 4. A multi-lens type lens having a large number of individual lenses for guiding light from a light source to an object to be exposed, and outputting light so that the lights emitted from the individual lenses overlap each other, and the light source. An exposure apparatus, comprising: a transmission-type polarization unit that mainly transmits first polarized light between the light source and the multi-lens type lens. 5. An exposure apparatus according to claim 4, wherein said polarizing means is a polarizing element group in which a transmission type polarizing element is opposed to each of said individual lenses. 6. The exposure apparatus according to claim 2, wherein the light source is a light source mainly emitting ultraviolet light.