JP3149791B2 - Film quality reformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film quality reforming apparatus used to improve the properties of a thin film, and more particularly, to a thin film such as an alignment film on a substrate of a liquid crystal panel through a mask. The present invention relates to a film quality reforming device used to irradiate light and improve its characteristics.

[0002]

2. Description of the Related Art There are two types of liquid crystal screens: a transmission type and a reflection type.
The transmissive liquid crystal screen is composed of a liquid crystal panel, a driver for controlling the liquid crystal panel, and a backlight for illuminating the liquid crystal panel from the back. The liquid crystal panel encloses liquid crystal and controls a voltage applied thereto to transmit or block light from a backlight to display a screen. In this case, the liquid crystal panel is composed of two glass substrates.

On the other hand, a reflection type liquid crystal screen utilizes room light without using a backlight, and one substrate is constituted by a semiconductor substrate having a mirror surface for reflecting light.
The room light incident on the liquid crystal panel passes through the glass substrate and the liquid crystal layer, is reflected by the reflecting mirror surface, and again passes through the liquid crystal layer and the glass substrate to display a screen. The reflective liquid crystal screen does not use a backlight, and thus has the advantage of low power consumption. Recently, a resin substrate has been used instead of a glass substrate for cost reduction. Usually, one of two substrates (a glass substrate, a resin substrate, or a semiconductor substrate) constituting a liquid crystal panel is provided with a driving element for driving liquid crystal, for example, a thin film transistor (TF).
T), a liquid crystal driving electrode formed of a transparent conductive film, an alignment film for aligning liquid crystal in a specific direction, and the like. On the other substrate (glass substrate, resin substrate), a light-shielding film called a black matrix, and in the case of a color liquid crystal panel, a color filter and the above-described alignment film are formed.

The alignment film is formed by applying a process called rubbing to the surface of a thin film of a polyimide resin or the like to form fine grooves (scratches) in a specific direction, and to specify liquid crystal molecules along the fine grooves. It works to orient in the direction of. For the rubbing treatment, a method in which a substrate is rubbed with a cloth wound around a rotating roller is widely used. In this case, rubbing is performed in the same direction over the entire surface of the substrate. It is known that a liquid crystal panel changes the contrast of an image depending on a viewing angle. The range of angles at which a good contrast is obtained is called the viewing angle of the liquid crystal panel. The larger the viewing angle, the better the visibility and the better the liquid crystal panel. Therefore, how to obtain a large viewing angle is an important technical problem.

As techniques for manufacturing a liquid crystal panel having a good viewing angle, Japanese Patent Application Laid-Open Nos. Hei 6-222366 and Hei 6
Japanese Patent Application Publication No. -281937 discloses a technique for controlling a pretilt angle of liquid crystal molecules. The pretilt angle refers to an angle at which a liquid crystal molecule rises at a certain angle with respect to the alignment film surface when it comes into contact with the alignment film. In the above publication, the alignment film is irradiated with ultraviolet light or the like through a mask to modify the characteristics of the alignment film. A liquid crystal panel having a wide viewing angle is manufactured by mixing regions having different pretilt angles in the same substrate by utilizing a phenomenon in which the pretilt angle of the alignment film in a portion irradiated with ultraviolet light is reduced.

It is considered that the phenomenon that the pretilt angle changes due to the irradiation of ultraviolet light occurs because the surface of the alignment film is oxidized by the ultraviolet light and the polarity of the alignment film changes.
For the modification of the alignment film, it is necessary to place the alignment film in a gas atmosphere containing oxygen at the time of irradiation with ultraviolet light. That is, when irradiating the alignment film with ultraviolet light through the mask, the mask and the alignment film surface (substrate surface) are kept at a distance, and a gas layer (air) containing oxygen is formed between the mask and the alignment film.

FIG. 13 is a schematic explanatory view of a conventional technique for modifying the characteristics of an alignment film by irradiating ultraviolet light as described above. In the figure, M is a mask, and the mask M has a mask pattern MP for partially blocking ultraviolet light as shown in FIG.
Are formed. Reference numeral 101 denotes a substrate (a glass substrate or a resin substrate; hereinafter, referred to as a work). The work 101 has the above-described thin film transistor (TFT), a liquid crystal driving electrode, etc. (not shown) formed thereon, and an alignment film 102 formed thereon. Have been.

In order to improve the characteristics of the alignment film 102, as shown in FIG. 1A, a mask M on which a mask pattern MP is formed is arranged so as to be separated from a work 101 on which the alignment film 102 is formed. (Distance enough to ensure the distance from the work 101 even if the mask M is bent by its own weight: for example, 10
UV light is irradiated from above the mask M. As a result, as shown in FIG.
The property of No. 2 is modified, and the pretilt angle of the portion irradiated with ultraviolet light changes. Ultraviolet light having a wavelength of 300 nm or less (especially 200 nm to 300 nm) is known to be particularly useful for modifying the properties of the above-described alignment film. Further, as a light source that emits light in this wavelength range, Low and high pressure long arc mercury lamps are known.

[0009]

[Problems to be solved by the invention]

(1) As described above, low-pressure and high-pressure long arc mercury lamps are known as lamps used for modifying characteristics of an alignment film and the like formed on a substrate (hereinafter referred to as a work). In these lamps, the distance between the discharge electrodes is as long as several tens cm to several hundred cm, and the area of the light emitting portion is large, so that strong ultraviolet light can be easily obtained. However, the ultraviolet light from these lamps is divergent. Therefore, as described above,
When divergent light is irradiated with the mask and the work surface separated to form a gas (air) layer containing oxygen between the mask and the work surface, light components obliquely incident on the mask are blocked by the mask. Wrap around inside. Therefore, ultraviolet light is irradiated to a part which is not originally desired to be modified, and an undesired part is modified. For example, when the divergent light is used in FIG. 13 described above, the ultraviolet light wraps around to the portion where the ultraviolet light is not desired to be irradiated, and changes to the pretilt angle of the portion where the pretilt angle is not originally desired to be changed.

On the other hand, when the distance between the mask and the work surface is reduced or brought into contact with each other in order to avoid the light
There is a problem that the amount of oxygen required for the reforming reaction is insufficient and sufficient reforming cannot be performed. Therefore, in order to avoid the modification of the undesired portions as described above, it is necessary to irradiate the mask and the work with parallel light using an optical system. By the way, when light is irradiated from the lamp to the work via the collimator lens, the light is incident on the work as shown in FIG.

FIG. 1 is a conceptual diagram when light is radiated from a lamp to a work through a collimator lens, and FIG. 2A is a lamp having a large light-emitting portion like the long arc discharge lamp described above. (B) shows a case where a lamp having a small light emitting portion area such as a short arc discharge lamp is used (hereinafter, the size of the light emitting portion is set to 5% or more of the maximum light emission luminance). Is represented by the arc length indicating the arc region of the above). The experiments by the inventors have revealed that the arc length and the distance between the electrodes when the lamp is not lit have the following relationship. When the lamp is turned on, the pair of electrodes (a cathode and an anode in the case of a DC discharge lamp) and the metal rod supporting these expand thermally. As a result, the distance between the electrodes decreased, but the amount of the decrease was about 0.5 mm regardless of the value of the distance between the electrodes.

On the other hand, since the arc is formed so as to cover the tip of the electrode (in the case of a DC discharge lamp, the cathode side), the length of the arc portion is larger than the distance between the electrodes at the time of lighting by 0.5.
mm long. That is, it became clear that the arc length and the inter-electrode distance during non-lighting were substantially equal, and it was found that the arc length could be obtained by measuring the inter-electrode distance during non-lighting. When a lamp having a long arc length, such as a low-pressure or high-pressure long-arc mercury lamp, is used, if a lens having good central ray parallelism (also called telecentricity) is used, as shown in FIG. The parallelism of the light emitted from the center of the lamp can be increased, but the light emitted from the end of the lamp is obliquely incident on the work (this angle is referred to as a viewing angle α. Is an optical term that has different meanings and definitions and represents the properties of light.) For this reason,
Good parallel light cannot be obtained and light wraps around.

A lamp having a long arc length has a large discharge area, and when an optical system including an integrator lens or the like is used, the area of light incident on the integrator lens increases. Therefore, it is necessary to increase the size of the integrator lens in accordance with the spread, and there is a problem that the price of the integrator lens increases. On the other hand, when a lamp having a short arc length such as an ultra-high pressure mercury lamp, an ultra-high pressure xenon mercury lamp, or an ultra-high pressure metal halide lamp is used, as shown in FIG.
And the parallelism of light can be increased. From this, it is better to use the above-mentioned short arc discharge lamp having a short arc length and to reduce the viewing angle α in order to prevent the light from wrapping around. However, if the viewing angle α is too small, the amount of light wraparound increases. It is considered that this is because light diffraction becomes large.

Therefore, when irradiating light to a work through a mask using a short arc discharge lamp,
Conventionally, the viewing angle α had to be increased to some extent by using a concave lens or the like. The short arc discharge lamp described above is designed to efficiently emit light of so-called i-line (365 nm), h-line (405 nm), and g-line (436 nm).
The irradiance of ultraviolet light of 00 nm or less is low. Further, in the above short arc discharge lamp, when the power applied to the lamp is increased in order to increase the emitted light,
The lamp current becomes considerably large, and the lamp power supply foil is easily damaged.

For this reason, in the short arc discharge lamp described above, sufficient irradiance cannot be obtained in a wavelength range necessary for modifying the film quality of the alignment film and the like, and when used as a lamp for modifying the film quality, There is a problem that the irradiation time becomes longer and the throughput is reduced.

(2) As described above, in order to modify a thin film such as an alignment film of a liquid crystal panel, a gas layer containing oxygen must be formed between a mask and a work. If the distance between the mask and the workpiece is too small, the mask may partially contact the workpiece due to the deflection of the mask, and the reforming may not be performed sufficiently. On the other hand, if the gap between the mask and the work is increased, it becomes necessary to increase the degree of parallelism of the light irradiated on the mask and the work, and a lamp, an integrator lens,
The design restrictions of the optical system including the collimator lens and the like increase. Further, even when the parallelism between the mask and the work is low, the gap between the mask and the work is partially widened, causing the same problem as described above. Therefore, it is necessary that the mask and the work are arranged in parallel with a sufficient gap to form a gas layer containing oxygen therebetween.

The present invention has been made in consideration of the above-described problems of the prior art, and a first object of the present invention is to provide a method using a mask arranged at a distance from an irradiated surface on a work. Provided is a film quality reforming apparatus that can prevent light from wrapping around when irradiating light to a work surface to modify the film quality on the work, and does not modify an undesired portion. That is. A second object of the present invention is to improve the film quality by irradiating the work with ultraviolet light having the irradiance and wavelength necessary for performing the film quality modification in a short time, thereby improving the throughput. It is to provide a device.
A third object of the present invention is to make a mask and a work parallel, and
An object of the present invention is to provide a film quality reforming apparatus capable of accurately positioning a gap in such a degree that oxygen required for reforming can be sufficiently secured.

[0018]

According to a first aspect of the present invention, there is provided an ultraviolet light irradiating section for irradiating a mask and a work with a parallel ultraviolet light substantially perpendicularly to the mask and a work. A work stage comprising a mask stage for holding, a work stage for holding the work and a moving mechanism for rotating and moving the work stage in the horizontal and vertical directions, and holding the work and the mask in close proximity to each other; A film quality reforming apparatus comprising a gap setting mechanism for forming a gas layer containing oxygen between the mask and a control unit for controlling each of the mechanisms, wherein the ultraviolet light irradiation unit emits at least ultraviolet light. Lamp, an elliptical condensing mirror, an integrator lens, a collimator lens or a collimator mirror, and the ultraviolet light irradiating unit sets the visual angle of ultraviolet light to α, When the thickness of the body layer is d and the minimum unit width of the region to be modified on the work is W, the conditions of α> 1.5 ° and d × tan α ≦ 0.1 W (d ≠ 0) are satisfied. The work is configured to irradiate the work with ultraviolet light through the mask.

According to a second aspect of the present invention, in the first aspect of the present invention, the lamp emitting the ultraviolet light is provided by bringing a pair of electrodes close to an arc tube made of quartz glass and at least mercury and a rare gas inside the arc tube. Wherein the arc length of the light source is 7.5 mm or more and 29 mm or less.

According to a third aspect of the present invention, in the first aspect of the present invention, the lamp emitting the ultraviolet light is provided by bringing a pair of electrodes close to a quartz glass arc tube and at least cadmium and a rare gas inside the arc tube. Wherein the arc length of the light source is 4.0 mm or more and 29 mm or less.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the lamp for emitting ultraviolet light and the elliptical converging mirror are provided with a spherical electrodeless arc tube having an inner diameter of 7.5 mm or more and 29 mm or less. A microwave cavity in which the electrodeless arc tube is housed and combined with microwaves, and which also serves as an elliptical condensing mirror, a magnetron for generating microwaves, and a microwave generated from the magnetron. A waveguide for guiding a wave to the microwave cavity, coupling means for coupling the microwave guided from the waveguide to the microwave cavity, and cooling means for cooling the electrodeless arc tube. is there.

[0022]

In order to avoid the wraparound of light and to modify only a desired portion of a work in a short time, an ultraviolet light having a predetermined range of viewing angle α, high central ray parallelism, and high irradiance is required. It is important to irradiate the mask and the work substantially perpendicularly, and to arrange the mask and the substrate in parallel with an interval enough to secure a sufficient amount of oxygen necessary for the reforming reaction.
In order to realize the above, while using a lamp having an appropriate arc length, an optical system composed of an integrator lens, a collimator lens, etc. is appropriately designed, has a viewing angle α in a predetermined range, and has a central ray parallel. It is necessary to obtain a high degree of ultraviolet light.

Here, as described above, if the viewing angle α is too small, the diffraction of light increases, and conversely, the amount of light wraparound increases. The magnitude of the viewing angle α at which light wraparound occurs due to the light diffraction is considered to be 1.5 ° or less. On the other hand, even if the viewing angle α is too large, light is obliquely incident on the mask as described above, and an undesired portion is modified.

The maximum value of the viewing angle α can be obtained as follows. That is, if the width of the light wraparound is equal to or less than 1/10 of the width W of the minimum part of the region to be modified, the image on the liquid crystal panel is not substantially adversely affected and can be tolerated. Further, the width of the light wraparound is a function of the thickness d of the gas layer (the distance between the mask and the work) and the viewing angle α of the light. Therefore,
The maximum value αmax of the viewing angle α can be expressed by the following equation. d × tan αmax ≦ 0.1 W Here, as described above, the thickness d of the gas layer is set to 100 μm,
The width W of the portion of the alignment film to be modified is also 100 μm.
Then, the maximum value αmax of the viewing angle α is about 5.7 °.

That is, when the work is irradiated with light through a mask arranged at an interval from the work to modify the film quality, it is desirable that the viewing angle α be within the following range. 1.5 ° <α ≦ αmax (approximately 5.7 °) On the other hand, as described above, the viewing angle α depends on the arc length of the lamp, and the longer the arc length of the lamp, the larger the viewing angle α. Is shorter, the viewing angle α becomes smaller.

That is, in order to keep the viewing angle α within a certain range, it is necessary to appropriately select the arc length of the lamp accordingly. Therefore, as described later, an arc length in which the viewing angle α falls within the above range was determined in consideration of design restrictions in realizing the optical system.
It was found that the arc length for obtaining the angle ° was about 7.5 mm, and the arc length for obtaining the viewing angle of 5.7 ° was preferably about 29 mm. Therefore, a lamp for irradiating a film on a work with light through a mask arranged at a distance from the work to modify the film quality, such as a modification of an alignment film of a liquid crystal panel, has an arc length of 7 mm. 0.5mm-29
mm is desirable. Similarly, when a spherical electrodeless arc tube is used, its inner diameter is 7.5 mm.
It is desirable to be within the range of 〜29 mm.

On the other hand, as described above, it is known that ultraviolet light having a wavelength of 200 nm to 300 nm is useful for modifying the film quality. In the modification of the film quality of the alignment film or the like of the liquid crystal substrate, ultraviolet light having a wavelength of 200 to 230 nm is more effective than ultraviolet light having a wavelength of 230 to 300 nm among the ultraviolet light (wavelength of 200 to 230 nm). UV light has a wavelength of 23
The effect is at least twice or more than 0 to 300 nm). As a lamp capable of emitting light including ultraviolet light having the above-mentioned wavelength, a mercury discharge lamp containing mercury in the range of 2 ≦ M ≦ 15 (mg / cc) described later, or 0.06 ≦
A cadmium discharge lamp in which metal cadmium is sealed within a range of C ≦ 3 (mg / cc) can be used.

Depending on the lamp input, if a mercury discharge lamp is further filled with Hg I ₂ or the like, and a cadmium discharge lamp is further filled with a halide or halogen such as Cd I ₂ , the electrode life and the illuminance deterioration life are extended. Therefore, they may be enclosed as needed (for example, Japanese Patent Application Laid-Open No. 7-57693). By the way, the intensity of the light emitted from the discharge lamp increases as the power applied to the arc (power contributing to light emission) increases.
That is, assuming that the electric power applied to the arc is W and the amount of enclosed mercury is constant, the irradiance E of the lamp is approximately E = a ×
W (a is a proportional constant), and the power W can be approximately represented by the relationship of W = b × A × I (b is a proportional constant, A is an arc length, and I is a current). The irradiance E can be approximately expressed by E = c × A × I (c is a proportional constant). Here, the upper limit of the current I depends on the electrode structure of the lamp, the cooling efficiency of the lamp, and the like. If the current is too large, the possibility of damage to the electrode increases, and the efficiency decreases due to a voltage drop at the electrode. Therefore, the upper limit cannot be inevitably fixed and cannot be increased unnecessarily.

That is, in order to increase the irradiance E of the lamp, it is necessary to increase the arc length A. In the case of a mercury discharge lamp, the emission of short-wavelength light having high energy is less than that of a cadmium discharge lamp. Therefore, in order to obtain sufficient irradiance for modifying the film quality, the arc length A needs to be 7.5 mm or more. is there. In contrast, cadmium discharge lamps emit a lot of short-wavelength light with high energy,
In particular, light around 215 mm where the absorption peak of the polyimide resin forming the alignment film is present is also emitted.

For this reason, when a cadmium discharge lamp is used, the same film quality modification effect can be obtained with an input power smaller than that of the mercury lamp. That is, it is sufficient that the input power can be reduced, the distance between the electrodes can be reduced, and the arc length A is 4.0 mm or more. Here, when the arc length is shortened as described above, the viewing angle of 1.5 ° cannot be secured as described above, and optical correction is required. As the optical correction, in FIG. 2 described later, (a) a concave lens 8 is provided between the lamp 1 and the integrator lens 3, (b) a convex mirror is provided in front of the integrator lens 3, (c) a lamp 1 is provided. Or the method of (d) offsetting the position of the lamp 1 from the focal position of the condenser mirror 2 can be used. As described above, if the diameter D of the light incident on the integrator lens 3 (the arc image on the incident surface of the integrator lens 3) is adjusted, even if the distance between the electrodes is shortened, it is possible to perform good film quality modification. A viewing angle of 1.5 ° can be secured. In the case of securing a viewing angle of 1.5 ° by the method (d), it is necessary to change the quality of light so as not to affect the optical performance.

As described above, in the lamp for modifying the film quality, the diameter of the light incident on the integrator lens is set so that the viewing angle falls within the range of 1.5 ° <α ≦ αmax (about 5.7 °). By adjusting D, it is possible to prevent the wraparound of light, and it is possible to perform good film quality modification. In particular, in a mercury discharge lamp, the arc length is 7.5 mm or more,
When the thickness is 29 mm or less, the configuration of the optical system can be simplified, and the irradiation energy required for film quality modification can be obtained. In a cadmium discharge lamp, if the arc length is 4.0 mm or more and 29 mm or less, optical correction is required when the arc length is 4.0 to 7.5 mm, but relatively small lamp power is required. Irradiation energy required for film quality modification can be obtained.

The same can be considered for the electrodeless arc tube. If the inner diameter of the spherical electrodeless arc tube can be set within the above range, the irradiance required for film quality modification can be obtained even in the electrodeless arc tube. Can be. In an electrodeless arc tube, the arc spreads almost entirely in the inner space of the spherical portion, and the inner diameter of the spherical portion of the arc tube is substantially equal to the arc length (diameter). The electrodeless arc tube is 300 nm or less (200 nm or less).
irradiance (nm to 300 nm) is larger than that of the above-described electrodeed discharge lamp, and is suitable for use in modifying the film quality. Further, since no electrode is provided, the lamp life is long. On the other hand, in order to realize the above, a mechanism for accurately positioning the mask and the work in parallel at a desired interval is required.

Therefore, in the present invention, the mask is supported by using the gap setting mechanism proposed earlier (see Japanese Patent Application Laid-Open No. 7-74096), and the workpiece is brought into contact with the mask so that both are parallel to each other. While keeping the mask and the work parallel, the work is separated from the mask by a desired amount, and the mask and the work are held parallel to a desired gap. As a result, the gap between the mask and the work can be accurately set to a desired value. For this reason, the value of the thickness d of the gas layer can be set to the minimum value, and the upper limit of the value of the viewing angle α can be increased.

The present invention has been made based on the above principle. According to the first aspect of the present invention, the film quality modifying apparatus includes a lamp, an elliptical condensing mirror, an integrator lens, a collimator lens or a collimator mirror. An ultraviolet light irradiator that irradiates parallel ultraviolet light, a mask and a mask stage, a work and a work stage, and a work and a mask are held close to each other to form a gas layer containing oxygen between the work and the mask. A gap setting mechanism to be configured, and a control unit that controls each of the above mechanisms, the visual angle of the ultraviolet light irradiated by the ultraviolet light irradiation unit is α, the thickness of the gas layer is d, and the property on the work is modified. When the minimum unit width of the area is W, α
Since the workpiece is irradiated with ultraviolet light that satisfies the conditions of> 1.5 ° and d × tan α ≦ 0.1 W (d ≠ 0) through the mask, light is prevented from sneaking around and undesired on the workpiece. Partial reforming can be prevented.

Further, the gap setting mechanism allows the mask and the work to be arranged in parallel with a distance necessary for forming a gas layer containing oxygen therebetween, and the value of the thickness d of the gas layer to be a minimum value. Can be set to Further, since the viewing angle α is in the above range, the arc length of the lamp that emits ultraviolet light can be increased, and the irradiation energy required for film quality modification can be secured.

According to the invention of claim 2 of the present invention, the lamp that emits ultraviolet light is constituted by a discharge lamp in which a pair of electrodes are brought close to a quartz glass arc tube and at least mercury and a rare gas are sealed in the arc tube. Since the arc length of the light source is not less than 7.5 mm and not more than 29 mm, a necessary viewing angle α can be secured without using an optical component such as a concave lens. Further, since the arc length is long, it is possible to easily secure irradiation energy required for film quality modification.

In the invention according to claim 3 of the present invention, the lamp that emits ultraviolet light is constituted by a discharge lamp in which a pair of electrodes are brought close to each other in a quartz glass arc tube and at least cadmium and a rare gas are sealed in the arc tube. Since the arc length of the light source is 4.0 mm or more and 29 mm or less, it is possible to sufficiently secure irradiation energy required for film quality modification with a small lamp power.

In the invention according to claim 4 of the present invention, the lamp which emits ultraviolet light has an inner diameter of 7.5 mm or more and 29 mm or less.
Since it is composed of the following spherical electrodeless arc tube, the lamp life can be made longer than that of a discharge lamp having electrodes.
Further, the wavelength is 300 nm or less (200 nm to 300 n
m) The irradiance of the ultraviolet light can be made larger than that of the above electroded discharge lamp. Further, similarly to the second aspect of the present invention, a necessary viewing angle α can be secured without using an optical component such as a concave lens.

[0039]

FIG. 1 is a diagram showing the overall configuration of a film quality reforming apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an ultraviolet lamp (hereinafter, abbreviated as a lamp). Electrodeless arc tube)
Consists of In addition, as the lamp 1, an AC discharge lamp having the same configuration as the DC discharge lamp can be used. Reference numeral 2 denotes a condensing mirror, and 3 denotes an integrator lens. A circular diaphragm (not shown) is provided immediately before or immediately after the integrator lens 3. This is for avoiding that the visual angle α of the light applied to the work is different depending on the direction on the work surface because the shape of the arc spot of the lamp 1 is not a perfect circle (true sphere). The shape of light can be shaped by providing a circular stop at the bottom.

4 is a shutter, 5 and 5 'are mirrors, and 6 is a collimator. A collimator lens (convex lens) or a collimator mirror (concave mirror) can be used as the collimator. In the figure, a collimator mirror (concave mirror) is used as a collimator. In addition, by using a collimator mirror (concave mirror) as the collimator 6, an irradiation device that irradiates a large area can be configured at a lower cost than when a collimator lens is used. Conversely, when irradiating a relatively small area, it is preferable to use a collimator lens because the optical axis adjustment and the like are easy. The above-mentioned 1 to 6 constitute an ultraviolet light irradiation section 7, and the ultraviolet irradiation section 7 shown in the figure shows a configuration in the case where a mercury or cadmium discharge lamp having an arc length of 7.5 mm to 29 mm is used. . When a cadmium discharge lamp having an arc length of 4.0 mm to 7.5 mm is used, it is necessary to perform optical correction to adjust the diameter of light incident on the integrator lens 3 as described above.

FIG. 2 shows a lamp 1 having an arc length of 4.0.
2 shows a configuration of the ultraviolet irradiation unit 7 when a cadmium discharge lamp having a diameter of 7 mm to 7.5 mm is used, and FIG. 4 shows a case where a concave lens 8 is used to adjust the diameter of light incident on the integrator lens 3. However, the above optical correction is performed by using a mirror as a convex mirror, changing the curvature of the condenser mirror 2, and further, changing the position of the lamp 1 as described above, in addition to using the concave lens. A method of offsetting from the focal position can be used. As shown in FIG. 2, by providing the concave lens 8 between the lamp 1 and the integrator lens 3, the arc image projected on the incident surface of the integrator lens 3 can be enlarged, and the arc length of the lamp 1 is set to 7. Even if shorter than 5 mm, a viewing angle of 1.5 ° can be secured.

In the ultraviolet irradiating section 7 shown in FIGS. 1 and 2, ultraviolet light emitted from the lamp 1 is condensed by the condenser mirror 2, and is directly used in the case of FIG. 1 or a concave lens in the case of FIG. The light enters the integrator lens 3 through 8. After the incident ultraviolet light is made uniform in intensity distribution by the integrator lens 3, it is made parallel by the collimator 6,
Incident on. The mask M shown in FIG. 1 is obtained by depositing and etching a metal such as chromium on a transparent substrate such as glass, for example, to form a pattern. W is a work such as a liquid crystal substrate on which the above-described alignment film is formed, and the mask M and the work W are arranged at a distance of about 100 μm as described above,
In the meantime, a gas layer containing oxygen is formed. The work W is placed on the work stage 15 so that the alignment film is on the upper surface, and is fixed to the work stage 15 by means such as a vacuum chuck.

The work W is usually formed from four or six liquid crystal substrates and has a maximum of 600 mm × 700 m.
m, usually a size of about 365 mm × 460 mm,
The work W is collectively irradiated with ultraviolet light to modify the alignment film of each substrate. In addition, while the work W is sequentially moved, each irradiation area of the work W can be sequentially exposed to modify the alignment film of each substrate. However, the case of the collective irradiation will be described below.

FIG. 3 is a view showing an example of a work in the present embodiment, and FIG. 3 shows a case where four liquid crystal panels are manufactured from one work. Referring back to FIG. 1, reference numeral 11 denotes a base for supporting the mask stage, reference numeral 12 denotes a mask stage for holding the mask M, and a mask stage 12 includes a positioning mechanism for setting the mask M at a predetermined position, and vacuum suction of the mask. And a vacuum chuck to be held. Reference numeral 13 denotes a gap setting mechanism. As the gap setting mechanism 13, the one disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 7-74096 can be used.
3 is at least 3 between the base 11 and the mask stage 12
And a mask M and a work W
Are set in parallel and the gap is constant.

Reference numeral 14 denotes a mask stage moving mechanism for moving the mask stage 12 to a predetermined position. The work stage 15 described above is operated by a work stage moving mechanism 16 in XYZθ (left and right, front and rear, up and down directions, and a stage surface). In the same manner as the mask stage 12, a positioning mechanism for setting the work W at a predetermined position and a vacuum for holding the work by vacuum suction are provided. And a chuck. As the work stage moving mechanism 16, Japanese Patent Application No. 6-201941, previously proposed by the present applicant,
Those described in Japanese Patent Application No. 6-201942 can be used.

Reference numeral 17 denotes an alignment microscope for matching the alignment mark marked on the mask M with the alignment mark marked on the work W. The alignment microscope 17 uses alignment light (usually visible light is used). Light source 17a that emits light, and the CCD sensor 1
7b, the light from the light source 17a is irradiated onto the mask / work, the reflected light is received by the CCD sensor 17b, and the alignment marks of the mask M and the work W are matched. Reference numeral 18 denotes a control unit. The control unit 18 includes a processor or the like, controls the positions of the mask M and the work W by the mask stage moving mechanism 14 and the work stage moving mechanism 16, controls the gap setting mechanism 13, and , The ultraviolet light irradiation unit 7 is controlled.

In the same figure, the modification processing of the work W on which the thin film is formed is performed as follows. First, the mask M is set at a predetermined position on the mask stage 12, and is held by vacuum suction. Next, the work stage 15 is lowered by the work stage moving mechanism 16, the work W is placed on the work stage 15, and is held by vacuum suction. Next, the work stage 15 is moved in the XYθ directions, and the work W is positioned below the mask M. Next, the control unit 1
Numeral 8 raises the work stage 15 by the work stage moving mechanism 16 to bring the work W into contact with the mask M, and then further raises the work W.

Here, the mask stage 12 and the base 11
A gap setting mechanism 13 is provided between the gaps, and the gap setting mechanisms 13 provided at at least three locations have a built-in compression coil, as described later, and are independently displaced. Therefore, even when the work W is inclined with respect to the mask M and the gap is not constant, the work W
Is further brought up by contact with the mask M, the compression coils of the gap setting mechanism 13 are displaced by different amounts, and the entire surface of the mask M comes into contact with the work W, and the inclinations of the mask M and the work W match. . At this point, the control device 18 holds the displacement state of each gap setting mechanism 13 and lowers the work stage 15 by a predetermined amount. As a result, the mask M and the work W are arranged in parallel with a gap such that a gas layer containing oxygen is formed therebetween.

By providing the gap setting mechanism 13 as described above, even if the work W is not in a state parallel to the mask M when the work W is mounted on the work stage 15, the work W and the mask M can be separated. The gaps can be set parallel and constant. When the distance between the work W and the mask M is set to a fixed value, the work stage moving mechanism 16 moves the work stage 15 in the XYθ directions,
The alignment mark marked on the top and the alignment mark marked on the work W are matched.

That is, the focus of the alignment microscope 17 is adjusted, the alignment mark of the mask M and the work W is received by the CCD sensor 17b, and the position of the work stage 15 is adjusted so that the two marks match.
This adjustment can be automatically performed by the control unit 18, but can also be manually performed while a person looks at the alignment microscope 17. When the alignment of the work W and the mask M is completed, the alignment microscope 17 retreats from above the mask M as shown by an arrow in the figure (note that the alignment microscope 17 is located at a non-irradiated portion on the mask). Need not retreat).

When the alignment marks of the mask M and the work W match, the shutter 4 of the ultraviolet light irradiation unit 7 opens,
The collimator 6 irradiates the parallel light onto the mask M, and the film quality is modified. When the irradiation is completed, the work stage 15 is lowered, the supply of vacuum to the work stage 15 is stopped, and the irradiated work W is taken out of the work stage. As described above, in the present embodiment, the mask M on which the pattern is formed is prepared, the mask M and the work W are arranged close to and parallel to each other, and only the portion where the characteristic of the work W is to be changed through the mask M is parallel. Since the light is irradiated with ultraviolet light, the work W can be modified without causing an undesired change in characteristics. In the above description, the case where the gap is set by moving the work stage 15 in the Z direction has been described. However, a means for moving the base 11 in the Z direction may be provided, and the gap may be set by moving the base 11. it can. Further, a gap setting mechanism can be provided between the work stage 15 and the work W.

Next, the ultraviolet light irradiation section 7 and the gap setting are set.
The mechanism 13 will be described. (1) Ultraviolet light irradiation section (a) Lamp The lamp 1 in the ultraviolet light irradiation section 7 is as described above.
DC or AC discharge lamp or electrodeless
A light tube can be used, and will be used hereinafter in the present invention.
The lamp to be used will be described. FIG.
Structure of DC discharge lamp used as membrane reforming lamp
It is a figure which shows an example of composition, In this figure, L1 is for DC
A discharge lamp, L2, is an arc tube of a DC discharge lamp,
The arc tube L2 is made of quartz glass and has
Is sealed with mercury and rare gas or metallic cadmium and rare gas.
Has been entered. Then, fill in mercury as described below.
In this case, the enclosed mercury amount M (mg / cc) is 2 ≦ M ≦ 15
And the sealed pressure P1 (Pa) of the rare gas is 0.1
× 10 ^Five≦ P1 ≦ 5 × 10^FiveWithin the range of
You.

When metal cadmium is encapsulated, the amount C (mg / cc) of encapsulated metal cadmium is 0.06.
≦ C ≦ 3, and the rare gas charging pressure P2 (Pa)
Is selected in the range of 0.1 × 10 ⁵ ≦ P2 ≦ 3 × 10 ⁶ . L3 is an electrode, and the electrode L3 is composed of an anode L3a and a cathode L3b. And the electrodes L3a, L
In the case of a mercury discharge lamp, the distance of 3b is approximately 7.5 mm to 29 mm so that the arc length is 7.5 mm to 29 mm.
mm, and in the case of a cadmium discharge lamp, the arc length is set to approximately 4.0 mm to 29 mm so that the arc length becomes 4.0 mm to 29 mm. Also,
L4 is a base. Although a discharge lamp for direct current is shown in FIG. 4, a discharge lamp for alternating current can be formed in the same manner. In the case of an alternating current, the electrode configuration is changed, but other configurations are basically the same. Configuration.

The amounts of mercury, cadmium and rare gas charged in the above-mentioned mercury discharge lamp and cadmium discharge lamp were selected as follows. As mentioned above, the wavelength of 2
It is known that ultraviolet light of 00 nm to 300 nm is useful. In the modification of the film quality of the alignment film or the like of the liquid crystal substrate, ultraviolet light having a wavelength of 200 to 230 nm is more effective than ultraviolet light having a wavelength of 230 to 300 nm among the ultraviolet light (wavelength of 200 to 230 nm). UV light has a wavelength of 230 to
It is at least twice as effective as 300 nm). Then, when the relative spectral irradiance of the mercury discharge lamp according to the difference in the amount of enclosed mercury was examined, the graph of FIG. 5 was obtained.

When the relationship between the irradiance of light in the above wavelength range and the amount of mercury sealed in the lamp was examined, the relationship shown in FIG. 6 was obtained. FIG. 6 shows a case where the power input to the lamp arc (power obtained by removing a loss such as voltage drop of the electrode from the lamp input) is constant.
Relative irradiance of the standard sphere (OPTRONIC LABORATORIE
The spectral irradiance in the horizontal direction of the lamp was measured from a distance of 1 m using a spectrometer calibrated using MODEL UV-40 manufactured by S, INC, and multiplied by 4π to obtain the total radiant light amount. From this result, the lamp for reforming the thin film has a mercury amount M (m
g / cc) within the range of 2 ≦ M ≦ 15.

Further, as shown in FIG. 6, the rare gas filling pressure P1 is desirably 0.1 × 10 ^{5 to} 5 × 10 ⁵ (Pa) when used as a lamp for reforming a thin film. . The irradiance is improved when the pressure of the rare gas is small, but when the pressure is 0.05 × 10 ⁵ (pa) or less, an arc is not formed from the tip of the cathode during lighting, resulting in an abnormal arc.
Therefore, in order to stabilize the lighting property, 0.1 × 10
⁵ (Pa) or more is required.

On the other hand, the relative spectral irradiance of the cadmium discharge lamp according to the difference in the amount of cadmium encapsulated metal was examined, and the graph shown in FIG. 7 was obtained. Further, when the relationship between the irradiance of light in the above wavelength range and the amount of metal cadmium enclosed in the lamp was examined, the relationship shown in FIG. 8 was obtained. FIG.
6 shows a case where the electric power input to the arc of the lamp is constant, as in FIG. From these results, it was found that the lamp for reforming the thin film had an enclosed metal cadmium amount C (mg /
It has been found that cc) is preferably in the range of 0.06 ≦ C ≦ 3. Further, as for the rare gas charging pressure P2 of the cadmium discharge lamp, when it is used as a lamp for reforming a thin film, the rare gas charging pressure is 0.1 × 10 ^{5 to} 3 × 10 ^{5 as} is clear from FIG. ⁶ (Pa) is desirable. The irradiance is improved as the sealing pressure of the rare gas is increased, but when the sealing pressure P2 is 3.8 × 10 ⁶ (Pa) or more, the pressure resistance is improved. It is necessary to increase the thickness of
It is desirable that the pressure be equal to or less than × 10 ⁶ (Pa).

As can be seen from FIG. 7, the radiated light of the cadmium discharge lamp has a wavelength of 200 to 200, which is particularly effective for modifying the film quality.
It contains much more ultraviolet light of 230 nm and is considered to be more suitable for film quality modification than a mercury discharge lamp. FIG. 9 is a diagram showing an example of the configuration of the electrodeless arc tube unit used in the present invention. When an electrodeless arc tube is used as a lamp, a unit shown in FIG. 9 is used instead of the lamp 1 and the condenser mirror 2 in FIG.

In FIG. 9, M1 is a spherical electrodeless arc tube, M2 is an elliptical condenser mirror and microwave cavity (cavity), M3 is a magnetron connected to a power supply (not shown), M4 is a waveguide, M5 Is a microwave introduction window, M6 is a motor for rotating the arc tube M1, and M7 is an arc tube cooling air pipe, through which the arc tube M1 cooling air is supplied. M8 is a metal mesh for preventing microwave leakage. In the figure, magnetron M3
Is generated by the waveguide M4 and guided into the elliptical condensing mirror / microwave cavity M2 from the microwave introduction window M5. Thereby, the arc tube M1
The mixed gas enclosed therein is excited to generate ultraviolet light. The arc tube M1 is rotated by a motor M6 and is cooled by cooling air blown from an arc tube cooling air pipe M7.

As the electrodeless arc tube M1, for example, a tube in which the following mixed gas is sealed can be used. Ball inner diameter φ: 7.5 mm to 29 mm (optimum value 18.5 m
m: volume 3.3 cm ³ ) Hg sealed amount: 8.65 mg / cc HgCl ₂ sealed amount: 0.03 mg / cc Ar sealed amount: 90 Torr (room temperature) Further, Hg and NaX, X (X is halogen), rare gas Can be used.

(B) Conditions of Ultraviolet Light Irradiation Apparatus for Setting Viewing Angle α to 1.5 ° <α ≦ 5.7 ° In the ultraviolet light irradiating section shown in FIG.
The condition for realizing (1.5 ° <α ≦ 5.7 °) was determined as follows. FIG. 10 is a simplified view of the ultraviolet light irradiation section shown in FIG. 1 and will be described with reference to FIG. It should be noted that the collimator mirror of the collimator 6 is replaced with a collimator lens (convex lens) for easy understanding. A collimator mirror (concave mirror) and a collimator lens (convex lens) are equivalent as a function of a collimator, and only an optical path differs in reflection or transmission.

(I) Relationship between viewing angle α and arc length Assuming that the arc length is A, the magnification of the elliptical converging mirror 2 is M, and the reduction coefficient of the integrator lens 3 by the stop is K, the diameter of light incident on the integrator lens 3 D is represented by the following equation (1). D = A · M · K (1) Next, the diameter of light incident on the integrator lens 3 is D, and the distance between the integrator lens 3 and the collimator 6 is L.
Then, the viewing angle α is expressed by the following equation (2). tan α = D / 2L (2) Therefore, the following expression (3) is obtained from the relationship of the above expressions (1) and (2). A = 2L · tan α / (M · K) (3)

(Ii) Calculation of arc length The magnification M of the elliptical converging mirror 2 is usually 10 to 60 times.
The smaller the magnification, the smaller the size of the integrator lens 3. However, since the angle of incidence of light incident on the integrator lens 3 becomes large, it is difficult to design the integrator lens and it is difficult to obtain uniformity. Conversely, if the magnification is increased, a large integrator lens is required according to the size of the enlarged arc spot.
The viewing angle worsens. For this reason, it is necessary to select an optimum magnification M of the elliptical condenser mirror 2 according to the application. In the following calculations, a factor of 18 was used. Further, the reduction coefficient K by the aperture is usually around 0.65 (in the case of an electrodeed discharge lamp).

The distance L between the integrator lens 3 and the collimator 6 is determined by the required irradiation area and the divergence angle β of the light emitted from the integrator lens 3. FIG. 10 shows the divergence angle β.
Indicates the half angle of the spread of the light emitted from the integrator lens 3 as shown in FIG. In other words, the larger the divergence angle β, the light expands at a shorter distance L, so that a large area can be irradiated with a compact optical system. However, when the divergence angle β is too large, the curvature of the collimator 6 becomes large, making the production difficult. Aberration becomes large.

Therefore, the divergence angle β is usually 5 to 15 °
Is used. In an application for manufacturing a liquid crystal panel, a large irradiation area is required because the substrate is large as described above. In the following calculation, 10.7 ° was used as the divergence angle β. For example, when the distance L between the integrator lens 3 and the collimator 6 required to irradiate a substrate of 400 × 500 mm with the divergence angle β is obtained as follows. L = (√ (400 · 400 + 500 · 500) / 2) /tan10.7°=1700mm When the arc length for obtaining the viewing angle of 1.5 ° and the viewing angle of 5.7 ° based on the above premise is obtained, the following is obtained. become that way.

Arc length A for obtaining a viewing angle of 1.5 °
1.5 M = 18, K = 0.65, L = 1700 mm, α = 1.
By substituting 5 ° into the above equation (3), A1.5 = 2L · tan α / (M · K) = (2 · 1700 · tan 1.5 °) / (18 · 0.65) = 7.6 mm ≒ 7.5 mm

Arc length A for obtaining a viewing angle of 5.7 °
5.7 M = 18, K = 0.65, L = 1700 mm, α = 5.
By substituting 7 ° into the above equation (3), A5.7 = 2L · tan α / (M · K) = (2 · 1700 · tan 5.7 °) / (18 · 0.65) = 29 mm By using a lamp having a length A of 7.5 mm to 29 mm, a viewing angle α of light incident on the mask M using an optical system that can be realized is 1.5 ° <α ≦ 5.
7 °. For this reason, it is possible to avoid the modification of an undesired portion due to the light wraparound. When a cadmium discharge lamp having an arc length shorter than the arc length A is used, the arc image projected on the incident surface of the integrator lens 13 is adjusted using an optical system such as a concave lens as described above. , The viewing angle α can be secured.

(2) Gap Setting Mechanism FIG. 11 is a view showing an example of a mode of attaching the gap setting mechanism to the mask stage 12 shown in FIG.
11 is a base, 12 is a mask stage, M is a mask, 1
3 is a gap setting mechanism, W is a work, and a gap setting mechanism 1
As shown in FIG. 3, three reference numerals 3 are vertically provided on the base 11. In order to determine the position on the mask stage 12, at least three gap setting mechanisms are required as shown in FIG. 3, for example, when the shape of the mask M is rectangular, the gap setting mechanisms are provided at four corners. You can also. In this case, a gap setting mechanism may be provided at each of the three corners, and the other may be a stretchable support having a built-in spring or the like.

FIG. 12 is an exploded perspective view showing an example of the structure of the gap adjusting mechanism, and the structure and operation of the gap setting mechanism of the present embodiment will be described with reference to FIG. Please refer to JP-A-7-74096 described above). In the figure, reference numeral 12 denotes a mask stage, 21 denotes a V-shaped receiver, and the V-shaped receiver 21 is embedded on the upper surface of the mask stage 12 and is connected to a ball receiver 41 via a hard sphere 22. At the center of the ball receiver 41, a conical recess 24 corresponding to the hard sphere 22 is provided. Therefore, when the mask stage 12 is pushed up from below, the mask stage 12 can freely move only in the direction of the V-shaped groove.

The mask stage 12 and the ball receiver 4
Numerals 1 are mutually attracted by a tension spring 23 and support the mask stage 12 in the direction of the base 11. A shaft 43 is connected above the ball receiver 41. The shaft 43 reaches a casing 46 via a spline 42 as a guide member. After penetrating the casing 46, the shaft 43 is connected to a leaf spring 45 as a plate-like elastic body. ing.
The shaft 43 slides in the spline 42, and the movement of the shaft 43 is restricted only in the vertical direction by the spline 42. Around the shaft 43 inside the casing 46,
A compression coil spring 44 that exerts a force on the shaft 43 is provided.

The leaf spring 45 is sandwiched between suction blocks 47 serving as holding means, and a projection 49 is provided on a part thereof. The suction block 47 is provided with a sensor 48 for detecting the position of the projection 49. Sensor 4
An optical sensor 8 includes, for example, a light emitting unit and a light receiving unit, and detects an interruption of light by the projection 49 to generate an output. Further, the suction block 47 is provided with a vacuum suction mechanism for sucking and holding the leaf spring 45 as described later. This vacuum suction mechanism can be operated by, for example, a rotary vacuum pump.

The gap setting mechanism of the present embodiment has the above-described structure. As described above, after the work W is raised and brought into contact with the mask M, the work W is further raised, and the work W and the mask M are separated from each other. When it reaches a position where it cannot move substantially any more, the compression coil spring 44 starts compressing so as to absorb the driving force. Due to this compression, the relative position of the leaf spring 45 with respect to the suction block 47 changes,
The protrusion 49 provided on the leaf spring 45 also moves, and the sensor 48
Detects this movement. That is, the amount of displacement of the mask stage 12 connected to the leaf spring 45 can be set based on the positional relationship between the protrusion 49 and the sensor 48.

As described above, each gap adjusting mechanism 1 provided on the mask stage 12 by raising the mask M
When 3 is displaced, the sensor 48 generates an output, which is sent to the control unit 18 described above. When the sensors 48 of all the gap setting mechanisms generate outputs, the control unit 18
Stops the movement of the work stage 15 in the Z direction, activates a vacuum suction mechanism (described later) provided in the suction block of each gap setting mechanism 13, and holds the compression state of the compression coil 44 of the gap setting mechanism 13. . As a result, the mask M and the work W are set in a parallel state. When the work stage 15 is lowered in this state, the mask M and the work W can be made parallel and the gap therebetween can be made constant.

[0074]

As described above, in the present invention, the following effects can be obtained. (1) The film quality reforming apparatus includes a lamp, an elliptical condensing mirror, an integrator lens, a collimator lens or a collimator mirror, an ultraviolet light irradiation unit for irradiating parallel ultraviolet light, a mask, a mask stage unit, a work, and a work stage unit. And a gap setting mechanism for holding the work and the mask close to each other and forming a gas layer containing oxygen between the work and the mask, and a control unit for controlling each of the mechanisms, and the ultraviolet light irradiation unit Α> 1.5 ° and d × tan α ≦ 0, where α is the viewing angle of the ultraviolet light to be irradiated, d is the thickness of the gas layer, and W is the minimum unit width of the region to be modified on the work. .
Since the work is irradiated with ultraviolet light that satisfies the condition of 1 W (d ≠ 0) through the mask, it is possible to prevent light from sneaking in and prevent modification of an undesired portion on the work.

(2) Since the gap setting mechanism is provided, the mask and the work can be arranged in parallel at a required distance, and the value of the thickness d of the gas layer can be set to the minimum value. (3) Since the viewing angle α is in the above range, the arc length of the lamp that emits ultraviolet light can be increased, and even when a mercury discharge lamp is used, the irradiation energy required for film quality modification is secured. can do.

(4) The lamp that emits ultraviolet light is constituted by a discharge lamp in which at least a mercury and a rare gas are sealed in an arc tube by bringing a pair of electrodes close to the arc tube of quartz glass.
Since the arc length of the light source is not less than 7.5 mm and not more than 29 mm, a necessary viewing angle can be secured without using an optical component such as a concave lens. Further, since the arc length is long, it is possible to easily secure irradiation energy required for film quality modification. (5) The lamp that emits ultraviolet light is constituted by a discharge lamp in which at least cadmium and a rare gas are sealed in an arc tube by bringing a pair of electrodes close to the arc tube of quartz glass, and the arc length of the light source is 4.0 mm or more. When the arc length is 4.0 mm to 7.5 mm, the necessary visual angle can be secured by performing optical correction using a concave lens or the like, and the film quality can be improved with a small lamp power. Required irradiation energy can be easily secured.

(6) Since the lamp that emits ultraviolet light is formed of a spherical electrodeless arc tube having an inner diameter of 7.5 mm or more and 29 mm or less, the lamp life can be made longer than that of a discharge lamp having electrodes. Further, the radiation intensity of ultraviolet light having a wavelength of 300 nm or less (200 nm to 300 nm) can be made larger than that of the above-described electrodeed discharge lamp. Further, similarly to the second aspect of the invention, a necessary viewing angle can be ensured without using an optical component such as a concave lens.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a film quality reforming apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a configuration of an ultraviolet irradiation unit when a cadmium discharge lamp having an arc length of 4.0 to 7.5 mm is used.

FIG. 3 is a diagram showing an example of an arrangement of a liquid crystal panel on a work.

FIG. 4 is a diagram illustrating an example of a configuration of a DC discharge lamp according to an embodiment of the present invention.

FIG. 5 is a diagram showing the spectral irradiance of a mercury discharge lamp.

FIG. 6 is a diagram showing the relationship between the amount of enclosed mercury and the integrated illuminance of ultraviolet light.

FIG. 7 is a diagram showing the spectral irradiance of a cadmium discharge lamp.

FIG. 8 is a diagram showing the relationship between the enclosed cadmium and the integrated illuminance of ultraviolet light.

FIG. 9 is a diagram showing a configuration of an electrodeless arc tube unit.

FIG. 10 is a simplified view of the ultraviolet light irradiation unit shown in FIG.

FIG. 11 is a diagram showing a mounting mode of a gap setting mechanism in the embodiment of the present invention.

FIG. 12 is a diagram illustrating an example of a structure of a gap setting mechanism according to the embodiment of the present invention.

FIG. 13 is a schematic explanatory view of modifying the characteristics of an alignment film by irradiating ultraviolet light.

FIG. 14 is a diagram showing a relationship between an arc length and a viewing angle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ultraviolet lamp 2 Condensing mirror 3 Integrator lens 4 Shutter 5 Mirror 6 Collimator 7 Ultraviolet light irradiation part 8 Concave lens 11 Base 12 Mask stage 13 Gap setting mechanism 14 Mask stage moving mechanism 15 Work stage 16 Work stage moving mechanism 17 Alignment microscope 17a Light source 17b CCD sensor 18 Control unit 21 V-shaped receiver 22 Hard ball 23 Tension spring 41 Ball receiver 42 Spline 43 Shaft 44 Compression coil spring 45 Leaf spring 46 Casing 47 Suction block 48 Sensor M Mask W Work L1 DC discharge lamp L2 Light emitting tube L3 Electrode L3a anode L3b cathode L4 base M1 electrodeless arc tube M2 elliptical condenser mirror and microwave cavity (cavity) M3 magnetron M4 waveguide M5 microwave introduction window M Motor M7 luminous tube cooling air pipe M8 metal mesh

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02F 1/1337 G02F 1/13 101

Claims (4)

(57) [Claims] 1. An ultraviolet light irradiator for irradiating a mask and a work with parallel ultraviolet light substantially vertically, a mask stage for holding the mask, a work stage for holding the work, and rotating and rotating the work stage. A work stage section comprising a moving mechanism for moving horizontally and vertically, a gap setting mechanism for holding the work and the mask close to each other and forming a gas layer containing oxygen between the work and the mask, and each of the above mechanisms And a control unit for controlling the ultraviolet light irradiation unit, wherein the ultraviolet light irradiation unit includes at least a lamp that emits ultraviolet light, an elliptical condensing mirror, an integrator lens, and a collimator lens or a collimator mirror. The ultraviolet light irradiating unit sets the visual angle of ultraviolet light to α, the thickness of the gas layer to d, and the minimum unit width of the region to be modified on the work to W. When, α> 1.5 ° and quality reformer and then irradiating ultraviolet light to satisfy the condition of d × tanα ≦ 0.1W (d ≠ 0) in the work through a mask. 2. A discharge lamp in which the ultraviolet light is radiated is a discharge lamp in which a pair of electrodes are brought close to an arc tube made of quartz glass and at least mercury and a rare gas are sealed in the arc tube. The film quality reforming apparatus according to claim 1, wherein the thickness is not less than 7.5 mm and not more than 29 mm. 3. The discharge lamp in which the ultraviolet light is emitted is a discharge lamp in which a pair of electrodes are brought close to an arc tube made of quartz glass and at least cadmium and a rare gas are sealed in the arc tube. 4.0mm or more 29
2. The film quality reforming device according to claim 1, wherein the thickness is not more than mm. 4. A lamp for emitting ultraviolet light, an elliptical converging mirror, a spherical electrodeless arc tube having an inner diameter of 7.5 mm or more and 29 mm or less, and the electrodeless arc tube housed and coupled to a microwave. A microwave cavity that forms a microwave cavity and also serves as an elliptical condensing mirror; a magnetron that generates microwaves; a waveguide that guides microwaves generated by the magnetron to the microwave cavity; 2. The film quality reforming apparatus according to claim 1, further comprising: coupling means for coupling the microwave guided from the waveguide to the microwave cavity; and cooling means for cooling the electrodeless arc tube.