JPH09325365A - Production of liquid crystal display element and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to execute developing of a resist film, peeling of the residual resist and processing of metallic thin films and semiconductor films, etc., with a completely dry process by irradiating the resist film with an excimer laser beam and removing the resist film of the irradiated parts. SOLUTION: A glass substrate 100 coated with the resist film 300 is irradiated with the excimer laser beam via an exposure mask 400 consisting of dielectric multilayered films as opaque films and having required opening patterns. Consequently, the resist patterns from which the resist of the parts corresponding to the opening patterns of the exposure mask 400 is removed are worked by the application phenomenon of the excimer laser beam and the multilayered films 200 are exposed at the required patterns. The glass substrate is then subjected to wet etching or dry etching and, thereafter, the remaining resist films are removed by full-surface application processing to irradiate the entire surface of the pattern forming surface with the excimer laser beam. The glass substrate 100 formed with the multilayered films 200 patterned to the required patterns is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal display element in which various thin films constituting a liquid crystal display element are formed on a glass substrate and a predetermined thin film pattern is formed on the thin film by lithography using a resist film. The present invention relates to a method and a liquid crystal display device.

[0002]

2. Description of the Related Art A liquid crystal display device is frequently used as an image display device used for a monitor of a television receiver or a personal computer. This type of liquid crystal display device includes a simple matrix type in which a liquid crystal layer is sandwiched between two sets of electrodes arranged in a matrix and one pixel is formed at the intersection of the electrodes, and a switching element such as a thin film transistor (TFT) for each pixel. Are roughly divided into active types.

In particular, active type liquid crystal display devices (TF
T-LCDs) have become the mainstream of liquid crystal display devices because of their high operating speed and contrast and high resolution.
In a thin film transistor type liquid crystal display device, a liquid crystal layer is sandwiched and bonded between one glass substrate on which a thin film transistor as a selection element is formed and the other glass substrate on which a color filter is formed, and a driving IC is mounted around the liquid crystal layer. At the same time, a backlight, which is an illumination light source, is installed on the lower surface.

A thin film pattern of a semiconductor or the like is formed on one of the above substrates by forming a thin film by sputtering, CVD, or the like, applying a resist on the thin film, and performing a series of photolithography such as exposure, development, etching, and resist stripping. A lithographic process is used. Similarly, the color filter film on the other substrate is also formed by a series of photolithography processes.

Conventionally, in this type of color filter, a black matrix is first formed on a transparent substrate such as a glass plate, and then red, green and blue filters are sequentially formed. These forming methods are so-called photolithography in which each material is made to have photosensitivity, these thin layers are formed, irradiated with ultraviolet rays through an exposure mask having openings of a predetermined pattern, and subjected to development processing. Is generally adopted.

Resist materials or photosensitive color filter materials used in this type of photolithography process are classified into a positive type in which solubility in a developing solution is generated by exposure and a negative type in which solubility is lost in contrast to this. However, pattern formation is performed by liquid development which is a wet process for each of the resist film or the color filter films applied to cover the thin film to be processed.

In the TFT thin film processing, a desired thin film pattern is obtained by a wet or dry etching process using the resist film formed by development as a mask. Then, after the etching process is completed, the remaining resist film is removed by a stripping solution or dry etching. As a disclosure of the prior art relating to this type of liquid crystal display device, for example, JP-A-63-309921 is disclosed.
Gazette and "12.5-inch active matrix color liquid crystal display with redundant configuration" (December 15, 1986)
Published by Nigmaglow Hill, Inc. Nikkei Electronics 1986
Dec. 15, pp. 193-210).

[0008]

The above-described conventional patterning of a resist film or a color filter film is formed by two processes of exposure and development. In the development process, a developer and a developing device are required, but the increase in the size of the substrate of the liquid crystal display device and a large increase in the production amount are accompanied by the use amount of the developing solution, the enlargement of the developing device, and the expansion of the clean space. This has led to an increase in the size of air conditioning equipment.

Along with this, the cost of waste liquid treatment of the developer,
Problems such as environmental impact also occur. The same occurs for the resist stripping process. In contrast,
Recently, a method has been proposed in which an excimer laser, which is an ultraviolet pulse laser, is used to process the resist for patterning the metal film, the dielectric insulating film, the thin film of the semiconductor film, and the black matrix and each filter material without wet development treatment. ing.

This processing method utilizes the ablation phenomenon of excimer laser light and has been used mainly in the field of micromachining in the past. on the other hand,
When an ablation phenomenon of an excimer laser is applied to pattern processing of a thin film having accuracy of a thin film transistor type liquid crystal display device, many problems occur in various points such as device configuration, accuracy, processing area and processing time.

That is, in the processing for making a hole in the circuit board, the processing pattern is circular at most about 30 μmφ, and the center-to-center positional accuracy of each is required to be ± 2 μm, but the circular shape accuracy is ± 5. About 10 μm is acceptable. Further, the thickness of the insulating layer of the circuit board is 20 to 50 μm, and processing using ablation of a conventional excimer laser is a technique belonging to a category of a processing region different from processing at the accuracy of an LSI level.

Further, in the above-mentioned processing utilizing the ablation phenomenon of the excimer laser, the ratio of the area or volume of the processed portion to the entire structure of the circuit board to be processed is very small, so that the utilization rate of the exposure light quantity is not determined. It is an important matter to improve the image quality, a unique illumination optical system is adopted according to the shape and thickness of the object to be processed, and the image formation is usually of the reduction type.

On the other hand, since a TFT-LCD panel (glass substrate) needs to form a fine repetitive pattern over a large area, the above-mentioned processing method utilizing the ablation phenomenon of the excimer laser is applied as it is. It is not possible. Further, when the excimer laser is simply used as the exposure light source of the exposure machine as in the case of VLSI, the light energy density of the excimer laser used is low, so that the optical system of the conventional exposure machine using the high pressure mercury lamp is used. No major changes required. However, when trying to use the ablation phenomenon, a much higher energy density is required compared with resist exposure of LSIs and the like, so the basic idea of the existing exposure machine can be used as an imaging system, but optical components can be used. It is necessary to have an optical system that takes into account the damage countermeasures.

That is, the ablation processing technique which requires TFT-LCD level accuracy cannot be applied as it is to the optical system employed in the conventional exposure machine from the viewpoint of processing accuracy and energy density. There is a problem. Further, the processing utilizing the ablation phenomenon of excimer laser light is, in principle, a thin film processing having a higher accuracy than the micromachining processing, for example, processing of a high-definition pattern forming level such as a TFT substrate of a TFT liquid crystal display element or a color filter substrate. Is fully possible.

There are several elemental technologies for realizing the processing of the above-mentioned high-definition pattern, and one of them is improvement of the processing resistance of the exposure mask exposed to the excimer laser beam. For example, when considering application to manufacture of a TFT substrate of a TFT liquid crystal display element, the pattern accuracy of the exposure mask needs to be at least 2 μm or less.

In consideration of resist ablation, an incident energy density of at least 100 mJ / cm ² or more is required. This depends on the imaging optical system, but the incident energy on the mask is at least 200 mJ / cm ^2.
This means that the exposure mask must have processing resistance to such high input energy in order to maintain processing accuracy.

Recently, the output of the excimer laser has been increasing more and more, and it is necessary to consider the incident energy to the exposure mask up to about 500 mJ / cm ² in view of improving the throughput. The output area of excimer laser light is smaller than that of a lamp for a normal exposure machine. If this is used as slit-shaped illumination light that covers the entire width of the substrate, there is a problem that the aperture of the imaging lens becomes large, which is not practical.

However, since this excimer laser is so-called invisible light, an alignment mark is formed in advance on the exposure mask, and the projected image of the alignment mark on the processed substrate is used as a guide for the photomask on the processed substrate. There is a problem that the conventional method of performing the alignment cannot be applied. Therefore, it is common to provide an optical system that projects the alignment mark of the photomask (exposure mask) with visible light, separately from the optical system that projects the photomask pattern with the excimer laser.

However, such a structure cannot avoid the complication caused by providing a separate optical system. Such a problem is also the same in a laser processing apparatus that performs processing by selectively irradiating an excimer laser through an exposure mask. As a countermeasure for the above, an exposure mask in which a dielectric film and a metal film are superposed may be used. However, the metal film is easily damaged by an intense ultraviolet laser beam, and how to superpose the dielectric film and the metal film There is a structural problem.

When a dielectric film for reflecting ultraviolet light is formed, since this dielectric film is often transparent to visible light, a normal optical system is used for alignment between the exposure mask and the substrate to be processed. Is difficult to use. Furthermore, debris, which is a processed product generated by ablation, should be cleaned after processing, or processed in an inert atmosphere such as helium, or processed in an oxygen atmosphere, depending on the processing material. Has been reduced by.

However, in the above-mentioned conventional technique, it is difficult to completely remove the debris generated by ablation. In particular, it is difficult to remove debris that has re-adhered to the workpiece. Further, the debris forms are distributed in a wide range from a gaseous state to particles with a size of several μm, depending on the type of material and the intensity of incident energy, and debris that has been washed after processing has also occurred. Various methods must be considered depending on the form.

Further, in processing in a helium atmosphere, debris is dispersed far away because the ejection speed of the ablation plume (explosion cloud) is faster than that in air, and apparently debris is reduced. appear. This is considered to be a result of the generated debris being oxidized and turned into a gas in an oxygen atmosphere. The above-described processing in an atmosphere of helium or oxygen is effective only in processing relatively limited materials, and is not effective in processing all materials.

Furthermore, the essential point to be considered is that when the oscillation frequency of the excimer laser is increased in order to perform high-speed processing, the plume generated by the preceding excimer laser pulse is still in the optical path of the excimer laser. Since the ablation by the subsequent excimer laser is performed in the state where the excimer laser exists, there is a problem that the excimer laser for the subsequent ablation causes energy loss.

For these reasons, removing the plume generated by ablation at high speed has become a more important issue than simply removing debris. In order to solve the above-mentioned problems of the prior art, the first object of the present invention is to develop a resist film, remove residual resist, and process a metal thin film, a semiconductor thin film, or a dielectric thin film using a complete dry method. It is an object of the present invention to provide a method for manufacturing a liquid crystal display device, which reduces manufacturing cost and solves environmental problems by performing the process.

A second object of the present invention is to provide a liquid crystal display device manufactured by developing a resist film and removing residual resist by a complete dry process using a new principle. A third object of the present invention is to provide a method of manufacturing a liquid crystal display device with high accuracy and avoiding damage to an optical system due to excimer laser light.

A fourth object of the present invention is to provide a method of forming a resist pattern for manufacturing a large size liquid crystal display element substrate using an exposure mask having a small area, and an apparatus therefor. A fifth object of the present invention is to provide an apparatus for manufacturing a liquid crystal display device having an excimer laser processing exposure mask formed of a high-precision dielectric multilayer film having increased processing resistance to excimer laser light. is there.

A sixth object of the present invention is to provide an apparatus for manufacturing a liquid crystal display element, which is equipped with an alignment device for aligning an exposure mask and a glass substrate with high accuracy with a simple structure. A seventh object of the present invention is to provide an apparatus for manufacturing a liquid crystal display device equipped with a device for removing debris generated by ablation processing using excimer laser light.

In the following description, an ablation processing device using an excimer laser is also referred to as a developing machine or an exposing machine.

[0029]

[Means for Solving the Problems]

[Structure for Achieving the First Object] In order to achieve the first object, the first invention according to claim 1 is a metal film for forming a liquid crystal display element, a dielectric insulating film. A thin film of a semiconductor film, or a multi-layered film in which a part of the thin film is formed in a pattern, is coated with a resist film made of a polymer material through a mask having a predetermined opening pattern. By excimer laser light irradiation to remove the resist film at the irradiated portion by an ablation phenomenon to form a resist film pattern exposing the thin film corresponding to the opening pattern of the mask, and exposed by the resist film pattern. After removing the thin film by etching, the residual resist film is removed by an ablation phenomenon by irradiating an excimer laser beam.

The second invention described in claim 2 is the absorption coefficient of the resist film in the first invention,
5 × 10 ⁴ cm for 48 nm excimer laser light
^-1 or more materials are used. Furthermore, a third invention according to claim 3 is characterized in that the polymer compound in the first invention is a thermosetting type which forms a cyclic or network crosslinked structure by either heating or drying. And

Further, the fourth invention according to claim 4 is as follows.
The resist film according to the first invention has a wavelength of 248n.
m, a material having an ablation speed of 0.04 μm / shot or more with respect to pulse light of an excimer laser having an energy density of 100 mJ / cm ² . [Structure for Achieving Second Object] In order to achieve the second object, a fifth invention according to claim 5 is a thin film of a metal film, a dielectric insulating film, a semiconductor film, or the above. One glass substrate obtained by processing a multi-layered film composed of one or a plurality of thin films by an ablation phenomenon of excimer laser light using a resist film made of a polymer material, and the other formed with a black matrix and a plurality of color filters. The liquid crystal device is configured by sandwiching a liquid crystal layer between the glass substrates.

In order to achieve the second object,
According to a sixth aspect of the present invention, the black matrix and / or the plurality of color filters of the glass substrate according to the fifth aspect of the invention have a predetermined opening pattern of the black matrix film and / or the plurality of color filter films. Irradiation with an excimer laser through a mask is characterized in that the black matrix film and / or a plurality of color filter films in the irradiated portion are processed by an ablation phenomenon. [Operation of the structure for achieving the first object] Ablation phenomenon of excimer laser light (Photo Deconposition Ablation)
The processing of polymeric materials by means of utilizing the phenomenon (cleavage) in which the bonds of the polymers are non-thermally broken by a short-pulse ultraviolet laser, and is capable of high-precision thin film processing. With.

By utilizing this ablation phenomenon, the resist film pattern can be formed only by the exposure process by the exposure machine using the excimer laser light, and the conventional development process can be completely omitted. Furthermore, the resist remaining after the pattern processing can be removed only by simple irradiation with excimer laser light, and a large-area resist stripping device and stripping solution, which are indispensable in the prior art, are unnecessary.

A resist material suitable for processing utilizing the above-mentioned ablation phenomenon must naturally have properties different from those of conventional resist materials. In other words, it is important that the excimer laser light is efficiently absorbed and the bonds between atoms are efficiently cleaved by the absorbed energy.
At present, there are four main oscillation frequency wavelengths of the excimer laser, but 248 nm or 308 nm is practical, and excimer laser light having a wavelength of 248 nm is particularly advantageous for breaking the bond.

As a result of studying the cleavage of various polymer materials with excimer laser light having a wavelength of 248 nm, the absorption coefficient of the resist film must be 5 × 10 ⁴ cm ^-1 or more in order to perform ablation processing at a high rate. It turned out that In order to exhibit such strong absorption, it is necessary for the resist material to have a substituent having an aromatic ring (Ar: aromatic). The difference in the absorption intensity due to the difference in the bonding mode of the substituent is almost uniquely determined by the direct bonding mode to the aromatic ring. In this regard, for example, "Absorpti
on Spectra in the Ultraviolet and visible region ''
(Edited by L. Lang, Akademimi Kiado, Budapest 196
It is clear by comparing the data in 6).

The bond in which the energy absorbed in the aromatic ring is efficiently converted into the cleavage is based on the results of the studies so far.
Examples thereof include imide resin, urethane resin, melamine resin, and epoxy resin. Among them, a polymer material having at least one type is a resist material most suitable for excimer laser light ablation processing. By using such a material, the absorption efficiency for excimer laser light having a wavelength of 248 nm or in the vicinity thereof can be improved.

It is non-thermal ablation that the polymer compound of the resist material for ablation processing of excimer laser light is a thermosetting type which forms a ring-shaped or net-like cross-linked structure by either heating or drying means. And it is necessary to realize a highly accurate machined end face. These are, of course, spin-coated, roll-coated, and rod-coated on thin films such as metal films, dielectric insulating films, and conductive films formed on glass substrates as resist materials or multilayer films in which a part of them are patterned. It is necessary that a uniform coating film of 3 μm or less can be formed by a coating means such as that described above. For this purpose, it is necessary to adjust a molecular weight, a mixing amount of a solvent, a surfactant, a filler, and the like to satisfy required coating characteristics. is important.

Further, as a resist material, after heat polymerization,
It is important that the underlying thin films have sufficient resistance to an etching atmosphere in wet etching or dry etching. 1 and 2 are process charts for explaining a method of manufacturing a liquid crystal display device according to the present invention using a resist material for ablation processing of excimer laser light having the above characteristics.

First, as shown in FIG. 1A, a glass film on which a metal film, a dielectric insulating film, a thin film of a semiconductor film, or a multilayer film 200 in which a part of the thin film is formed in a pattern is formed. On the substrate 100, a uniform coating film of 3 μm or less is formed on the resist film 300 by coating means such as spin coating, roll coating, and rod coating (b).

Glass substrate 1 coated with resist film 300
00 is irradiated with an excimer laser beam having a wavelength of, for example, 248 nm through an exposure mask 400 having a required opening pattern using a dielectric multilayer film as an opaque film (c). At this time, the excimer laser light is imaged on the resist film 300 by the imaging lens of the laser light from the excimer laser. The irradiation energy density is 50 mJ / cm ² or more and 300 mJ / cm ² or less.

As a result, as shown in (d), the resist pattern in which the resist in the portion corresponding to the opening pattern of the exposure mask 400 has been removed is processed by the ablation phenomenon of the excimer laser light, and the metal film and the dielectric insulation. film,
The thin film of the semiconductor film or the multilayer film 200 in which a part of the thin film is formed in a pattern is exposed in a required pattern.

Then, as shown in FIG.
(D) The glass substrate is subjected to wet etching or dry etching to remove the exposed portions of the metal film, the dielectric insulating film, the thin film of the semiconductor film, or the multilayer film 200 in which a part of the thin film is formed in a pattern. Thus, a required pattern is formed. Then, a wavelength of 248 nm or a wavelength of 308 nm having an energy density of 150 mJ / cm ² or less.
The remaining resist film is removed by the entire ablation process of irradiating the entire surface of the pattern formation surface with the excimer laser light of (f), and the metal film, the dielectric insulating film, the thin film of the semiconductor film, or the above-described thin film patterned into a desired pattern is formed. A glass substrate 100 having a multilayer film 200 in which a part of the thin film is formed in a pattern is obtained (g).

As described above, except for the etching process, only two excimer laser light irradiation devices for exposure and stripping are required as a lithographic apparatus, and since a mask is not used particularly for the resist stripping apparatus, An excimer laser light irradiation device, which has an extremely simple structure and is inexpensive, can be used, and the cost of the manufacturing device can be significantly reduced. [Operation of Configuration for Achieving Second Objective] For example, T
A thin film of a metal film, a dielectric insulating film, and a semiconductor film for forming a thin film transistor on a TFT substrate (switching element side substrate) which is one glass substrate in the case of FT-LCD,
Alternatively, the multi-layered film composed of one or a plurality of the thin films is processed by an ablation phenomenon of an excimer laser using a resist film made of a polymer material.

By sandwiching a liquid crystal layer between this glass substrate and the other glass substrate on which a black matrix and a plurality of color filters are formed, a high quality liquid crystal display device which is low in cost and does not affect the environment Is obtained. Further, the black matrix and / or the plurality of color filters of the other glass substrate process the black mask film and / or the plurality of color filter films by an ablation phenomenon of an excimer laser using a resist film made of a polymer material. By using such a liquid crystal display device, it is possible to obtain a liquid crystal display device of high quality which is lower in cost and does not affect the environment. [Structure for Achieving Third Object] In order to achieve the third object, the present invention has a structure shown in FIG. 3 and described below.

FIG. 3 is a schematic diagram for explaining an example of the structure of an exposure machine utilizing the ablation phenomenon of excimer laser light used for manufacturing the liquid crystal display element according to the present invention, in which 1 is an excimer laser, 3 and 5 are lenses, 4 is a split lens, 6
Is a condenser lens, 7 is an exposure mask, 8 is an imaging lens, 9 is an entrance pupil, 10 is a resist-coated glass substrate which is a workpiece, 11 is an XY table (11a is an XY mask table, 11b is X -Y substrate table).

In the figure, (1) an ultraviolet light pulse laser is used as the excimer laser 1, and the output light beam (excimer laser light) from this excimer laser 1 is exposed mask 7 having a predetermined aperture pattern and imaging lens 8. A workpiece (resist-coated glass substrate, hereinafter also simply referred to as a workpiece) 10 placed on the imaging surface is irradiated with the light to form a pattern by a pattern ablation phenomenon corresponding to the opening pattern of the exposure mask 7 (development). To do.

The output light beam of the excimer laser 1 is divided into a large number of light beams having a small area, each light beam is focused, and each focusing point is used as an illumination light source to uniformly illuminate the surface of the exposure mask 7. Further, an image of the illumination light source is formed on the entrance pupil 9 of the imaging lens 8, and the aperture pattern of the exposure mask 7 is formed on the limited area of the workpiece 10 placed on the imaging surface of the imaging lens 8. By forming a one-to-one image and scanning the limited area over the entire area of the workpiece 10, a pattern corresponding to the aperture pattern of the exposure mask 7 due to the ablation phenomenon is developed and formed on the entire area of the workpiece 10.

(2) The output light beam of the excimer laser 1 passes through the exposure mask 7 having a predetermined aperture pattern and the image forming lens 8 and is placed on the image forming surface of the object 10 to be processed.
A liquid crystal display device using an ablation phenomenon of an excimer laser beam for developing and forming a pattern corresponding to an opening pattern of the exposure mask 7 on the workpiece 10 by an ablation phenomenon. A lens array 4 for dividing the output light beam into light beams having a small area and condensing the light beams; an illumination optical system 6 for uniformly irradiating the surface of the exposure mask 7 using the converging point of the lens array 4 as an illumination light source; An imaging lens 8 having an entrance pupil 9 for forming an image of the exposure mask 7 illuminated by the illumination optical system 6 on a limited area of the workpiece 10 in a one-to-one manner; XY tables 11a and 11b for moving the exposure mask 7 and the workpiece 10 in two directions parallel to the plane of the exposure mask 7 so as to scan the limited area. By scanning the entire object 10, characterized in that a configuration ablating development to form developing a pattern corresponding to the opening pattern of the exposure mask 7 by ablation phenomenon over the entire workpiece 10.

The XY tables 11a and 11b are used.
Can be used to move one table 11a for exposing mask movement and the other table 11b for moving workpieces, and relatively move both directions in one direction (eg, X direction) and the other direction (eg, X direction) orthogonal to the one direction. (Y direction). Further, (3) the illumination optical system in (2) above,
The lens array 4 is provided with a lens 3 for collimating the output light beam of the excimer laser 1 into a parallel beam along the optical axis before splitting it into a light beam of a small area by the lens array 4, and the lens array 4 comprises an even number of lenses. Each of the two sets constitutes an array of a first lens and a second lens for splitting and condensing the output light beam of the ultraviolet light pulse laser incident in parallel, The focal point created by one lens is located in the middle of the second lens, and is arranged so that the luminous flux diverging from the focal point is completely contained within the corresponding lens area of the second lens. A third lens 5 for condensing each light flux emitted from the second lens in the same area is installed in the vicinity of the surface of the exposure mask 7 in the subsequent stage of the lens, and the third lens 5 is installed in the vicinity of the surface of the exposure mask 7 Exposure of the light collecting surface by Characterized in that a fourth lens 6 for forming an image of the focal array by dividing lenses on the entrance pupil 9 of simultaneously imaging lens 8 when fully match the surface of the disk 7.

(4) In the illumination optical system in the above (3), when the cross section of the output light beam of the ultraviolet light pulse laser 1 is taken as the XY coordinate plane, it is independent of each other parallel to the X axis and the Y axis. It is characterized in that it is configured by an optical system, and each optical system is configured by a cylindrical lens having a coordinate axis formed by the X axis and the Y axis as a cylindrical axis. (5) The fourth lens 6 constituting each of the X-axis and Y-axis optical systems in (4) above is a single aspherical lens.

(6) The image forming lens 8 in (2) above is a telecentric symmetrical lens constructed such that the portion of the lens where the light beam is most narrowed is hollow. (7) The exposure mask 7 in (2) above is formed by patterning a dielectric multi-layered film serving as a reflective film for the wavelength of the output light beam of the excimer laser 1, and the workpiece 10 placed on the image plane is formed. Both the workpiece 10 and the exposure mask 7 are moved so as to be point-symmetric with respect to a point on the optical axis of the imaging lens 8.

Further, (8) the illumination area to the exposure mask 7 in (7) above is a rectangle, and the length of its long side is a range that satisfies the predetermined resolution and image distortion of the symmetrical lens in (6) above. When the exposure mask 7 and the workpiece 10 are continuously moved in the short side direction to reach the ends of the workpiece 10 and the exposure mask 7, the exposure mask 7 and the workpiece 10 are arranged in the longitudinal direction of the illumination area. Is moved and then continuously moved in the direction of the short side to repeat scanning to perform ablation processing on the entire region of the workpiece 10.

Furthermore, (9) the rising of the energy density distribution at the end of the long side of the rectangular illumination area on the exposure mask 7 in the above (8) is set to 50 μm or less from the end of the short side. The exposure mask 7 has an illumination area adjusted by a rectangular opening pattern by a knife edge or a rectangular opening pattern of a dielectric multilayer film on the upper part of the exposure mask 7, and the short side of the rectangular opening pattern is located in the middle between the opening patterns. It is characterized by doing.

(10) XY which makes the output light beam of the excimer laser 1 in (2) above horizontal and holds the exposure mask 7 and the workpiece 10
With the tables 11a and 11b in the horizontal direction, the illumination light is made incident on the surface of the exposure mask 7 by only one 45-degree reflection, and the above-described (6)
Is arranged.

(11) In (10), the fourth lens of the illumination optical system of (2) and (3) is replaced by 4
It is characterized in that it is arranged at the subsequent stage of the 5-degree reflection mirror and immediately before the exposure mask 7. Further, (12) above (10)
In the above, the light source section consisting of the ultraviolet light pulse laser 1 and the ablation developing section consisting of the components excluding this light source are installed in separate rooms with different cleanliness, and are composed of the ultraviolet light pulse laser. It is characterized in that the laser light beam (excimer laser light) emitted from the light source section is introduced into the ablation developing section through a transmission window plate provided on the separation wall.

Further, (13) each of the ablation developing section consisting of a light source section consisting of the excimer laser 1 in (12) above and a constituent section excluding the light source is installed on a vibration-isolated floor. Further, (14) above (12)
The deviation of the laser light beam emitted from the light source unit including the excimer laser 1 with respect to the optical system forming the ablation developing unit is corrected by converting it into the inclination of the transmission window plate.

As described above, in the method and apparatus having the above-described configurations, in particular, the light absorption film (BM, so-called black matrix) of the color filter substrate or the color filters of the three colors that constitutes the color liquid crystal display panel such as the TFT is used. It is suitable for patterning a color filter thin film when forming and patterning with various resists and resist patterns of various thin films constituting a TFT substrate. [Operation of Configuration for Achieving Third Object] This configuration utilizes the ablation phenomenon of excimer laser light, and in particular, the light of a TFT component film or a color filter substrate that configures a color liquid crystal display panel such as a TFT. Absorption film (MB,
High-definition pattern processing such as patterning of a resist thin film when forming a so-called black matrix) or a color filter of three colors and patterning of a resist of each TFT layer is performed.

As described above, the ablation phenomenon is
When ultraviolet excimer laser light (excimer laser light) having a high energy density is applied to a material, the material that is exposed to light is photolyzed (cleaved) and scattered. Therefore, when the excimer laser light is irradiated so as to form an image on the substance through the exposure mask having the opening pattern, the substance has a pattern according to the opening pattern of the exposure mask.

Decomposition of a substance when irradiated with laser light having a wavelength longer than that of visible light is mainly caused by a thermal process, but in the case of excimer laser light, chemical bonds are directly cut particularly for many organic substances. Decomposes due to a non-thermal process. The development of a resist film utilizing the ablation phenomenon (ablation development) is to form a pattern on a resist or the like by utilizing such non-thermal photolysis, and exposure by conventional photolithography,
This is a processing method in which the two development steps are completed only by the exposure step.

As is clear from the above description, the apparatus for performing ablation development is essentially an exposure machine, and the principle of the optical system is that the pattern of the exposure mask is imaged on the resist film with a required accuracy. The same is true for machines. The basic conditions of the optical system of the exposure machine are that the light intensity distribution on the image forming surface is uniform and that the required accuracy of the image forming pattern is satisfied. Under this condition, the optical system of the exposure apparatus is divided into two parts, an illumination optical system and an imaging lens system. The former mainly determines uniform illumination, and the latter determines imaging performance. [Structure for Achieving Fourth Object] A method for forming a resist pattern for manufacturing a large-sized liquid crystal display element substrate (glass substrate) using a small-area exposure mask, which is the fourth object of the present invention, and a method therefor. The device is achieved by having the following configuration.

(1) Using an excimer laser having a wavelength of 248 nm or 308 nm as a light source, an illumination optical system for illuminating an exposure mask having a predetermined opening pattern made of a dielectric multilayer film in a slit shape, and X and holding the exposure mask. An X-Y table (X-Y mask table) that can be moved in the Y direction, a refraction-type symmetrical imaging optical lens that projects the aperture pattern of the exposure mask onto the substrate that constitutes the liquid crystal display device in a 1: 1 ratio, and the above glass. Using an exposure machine whose main component is an XY table (XY substrate table) that holds the substrate and can move in the X and Y directions independently of the XY mask stage. -Move the Y substrate stage one-dimensionally in the same direction or in the opposite direction to change the opening pattern of the exposure mask by the ablation action of the excimer laser light. A resist layer coated on the glass substrate 1: to form a 1.

(2) As the dielectric exposure mask for a liquid crystal display element in the above (1), the pattern of each layer of the pixel portion is divided into integers, and the patterns other than the pixels are appropriately divided.
A mask pattern is formed by enclosing each unit in a non-transmissive portion in parallel with the scanning direction, and the XY mask table and the XY substrate table are set at the scan start position corresponding to each mask pattern. Then, the corresponding exposure mask area is scanned, and then the exposure mask is returned to the original position, and the substrate is moved to the next repetition position to perform a similar scan (step-scan), and thereafter, the same process is repeated. Thereby, the entire pattern of the liquid crystal display element is formed.

(3) A resist pattern forming method for forming a required thin film pattern on an insulating substrate which constitutes a liquid crystal display element is such that a predetermined opening pattern is formed in an area smaller than the area of the thin film pattern forming region of the liquid crystal display element. The exposure mask has a relative movement within a plane parallel to the thin film pattern forming region, and the substrate is subjected to an ablation phenomenon by irradiating the exposure mask with slit-shaped excimer laser light in a direction orthogonal to the relative movement direction. It is characterized in that the resist applied thereon is patterned according to the opening pattern of the exposure mask.

(4) Further, the exposure mask has an opening pattern obtained by dividing the resist pattern in the pixel region of the insulating substrate into unit areas of an integer and an opening obtained by dividing the resist pattern other than the pixel area into appropriate unit areas. A pattern and a region surrounding each unit region with an opaque portion parallel to the scan direction, and X corresponding to each opening pattern.
A step of step-moving the Y mask table and the XY substrate table in a direction orthogonal to the length direction of the slit of the slit-shaped illumination light of the excimer laser light;
The whole surface of the resist on the substrate is patterned by scanning.

(5) Then, a resist pattern forming apparatus for forming a plurality of thin films constituting a liquid crystal display element on a glass substrate and forming a resist pattern for patterning the thin film is an excimer laser having a wavelength of 248 nm or 308 nm. A light source that emits light, an exposure mask made of a dielectric multilayer film having a predetermined opening pattern, an illumination optical system that illuminates the exposure mask in a slit shape with excimer laser light, and an excimer laser light that holds the exposure mask. In the plane perpendicular to the optical axis of and the Y orthogonal to the X direction
XY mask table movable in the direction, a refraction-type symmetric imaging optical lens for projecting the opening pattern of the exposure mask 1: 1 onto the insulating substrate, and XY holding the insulating substrate.
At least an XY substrate table that is movable independently of the mask table in the X direction in a plane parallel to the XY mask stage and in the Y direction orthogonal to the X direction,
By scanning the XY mask table and the XY substrate table one-dimensionally in the same or opposite directions,
The opening pattern of the exposure mask is patterned 1: 1 on the resist layer applied on the glass substrate by the ablation action of the excimer laser light passing through the opening pattern of the exposure mask. [Operation of Configuration for Achieving Fourth Object] With the above configuration, by utilizing the step-scan exposure means and the ablation phenomenon of excimer laser light, pattern exposure and development of a resist on a large-sized glass substrate can be performed. Is integrated, and a high-speed and low-cost resist patterning process is realized. [Structure for Achieving Fifth Object] The fifth object of the present invention is to include a high-precision dielectric multilayer film with increased process resistance to excimer laser light provided in a liquid crystal display device manufacturing apparatus. The exposure mask for excimer laser processing forms a dielectric multilayer film or the like satisfying the following requirements (1) to (5) on the surface of the glass substrate, which is transparent to ultraviolet light, opposite to the light incident surface. To be achieved. (1) On a glass substrate, a first layer having an optical path length of ¼ wavelength used, and a second layer having an optical path length of ¼ wavelength are stacked on the first layer. The refractive index of the first layer is higher than the refractive index of the second layer, and a quarter-wavelength optical path length having a refractive index higher than the refractive index of the substrate glass is formed on the dielectric multilayer film having the above configuration. It has a multilayer structure in which a third dielectric layer is formed.

When forming the dielectric pattern, a resist is used.
After forming the pattern, the pattern is formed by ion milling.
Forming a turn or depositing a metal film on the top layer,
Etching only this metal film to obtain the desired metal film pattern
Is formed, and this is used as an exposure mask for dry etching.
The dielectric layer is patterned more. (2) Transmits through the dielectric layer for the wavelength used in the above structure
Ablation of the work film on the substrate
The dielectric layer is formed so as to be below the threshold value. (3) The dielectric patterning mass in (1) above
Structure in which the metal film is left as it is as a constituent material of the exposure mask
And At this time, the dielectric layer for the excimer laser light
Permeation energy density is less than the damage threshold of the metal film
The film thickness is set so that (4) Particularly Cr is used as the metal film in the above structure.
You. (5) L as a low refractive index material that constitutes the above-mentioned dielectric layer
iF, MgF_Two, SiO _Two, YF_Three, LaF_Three, ThF
_FourUsing Al as the high refractive index material_TwoO_Three, MgO, T
hO_Two, Sc_TwoO_Three, Y_TwoO_Three, HfO_TwoOne of
Is used.

More specifically, the structure will be described in more detail. The exposure mask has a glass substrate transparent to ultraviolet light and a dielectric multilayer film pattern for selectively reflecting the wavelength of ultraviolet light formed on the glass substrate. The dielectric mask is formed. Further, the exposure mask has a glass substrate which is transparent to ultraviolet light and a film whose optical path length is ¼ wavelength of the used ultraviolet light on the surface of the glass substrate opposite to the ultraviolet light incident side. A first dielectric layer and a second dielectric layer having an optical path length of ¼ wavelength and smaller than the refractive index of the first dielectric layer are overlaid on the first dielectric layer. And a dielectric multilayer film formed by repeatedly forming a combination of two-layer films, and the uppermost layer of the dielectric multilayer film has a refractive index larger than that of the glass substrate, and its optical path length is 1/4 of the ultraviolet light used. It is characterized by having a third dielectric layer having a wavelength.

Further, the liquid crystal display device manufacturing apparatus uses an excimer laser beam of 248 nm and 308 n as ultraviolet light.
m, 351 nm, and the transmission energy density of the dielectric layer formed on the glass substrate at each of the above wavelengths is set to be equal to or less than the ablation threshold of the film to be processed. Furthermore, a metal film is formed on the third dielectric layer, and the transmission energy density of the dielectric layer at each wavelength of the excimer laser light is set to be equal to or less than the damage threshold of the metal film. And

The material of the metal film is Cr. In addition, the first layer forming the dielectric layer
The dielectric material is Al ₂ O ₃ , MgO, ThO ₂ , Sc ₂
Any one of O ₃ , Y ₂ O ₃ , and HfO ₂ or a combination of two or more thereof, wherein the second dielectric material is LiF, MgF.
It is characterized by being any one of ₂ , ₂ , SiO ₂ , YF ₃ , LaF ₃ , and ThF ₄ or a combination of two or more.

Then, the exposure mask is formed by forming a first dielectric layer having a film thickness of ¼ wavelength of the used ultraviolet light on the glass substrate which is transparent to the ultraviolet light, First
The optical path length is also 1/4 wavelength and the first
After forming a dielectric multilayer film formed by forming a second dielectric layer smaller than the refractive index of the dielectric layer, the uppermost layer of the dielectric multilayer film has a refractive index larger than that of the glass substrate and A dielectric multilayer film forming step of forming a third dielectric layer whose optical path length is １ ／ wavelength of the used ultraviolet light, a metal film forming step of forming a metal film on the dielectric multilayer film, A metal film patterning step of forming an opening pattern as an exposure mask by photolithography, and a dielectric multilayer film patterning step of forming an opening pattern as an exposure mask on the dielectric multilayer film by etching using the opening pattern of the metal film as a mask It is characterized by including. [Function of Configuration for Achieving Fifth Objective] The function of selective reflection and the like of the dielectric multilayer film is applied to a filter, a mirror, an antireflection film, etc.
M. Born & E. Wolf, "Primciples
of Optics "4th Edition 19
70 pp51-70.

According to the above-mentioned document, the reflecting mirror is constructed by alternately superposing a high-refractive-index quarter-wave film and a low-refractive-index quarter-wave film so that a given reflectivity can be obtained depending on the refractive index and the number of layers. Can be obtained. In the present invention, the application to the case where an exposure mask is irradiated with excimer laser light to form an opening pattern image of the exposure mask on the film substrate to be processed is defined as the first meaning, and the incident light is perpendicular to the mask surface. In most cases, only the vertical incidence will be discussed below. In this case, as shown in the equation 96 on page 69 of the above-mentioned document, the reflectance R (2
N) is given by the following equation (1).

[0072] R (2N) = _{{[1- (n e / n 1)} × (n 2 / n 3) 2N ] / _{[1 + n e / n 1)} × (n 2 / n 3) 2N ]} ² (1) where n ₁ is the refractive index of the incident medium forming the mask, n _1
e is the refractive index of the refractive _index, n 2, n ₃ are respectively the refractive index of the high refractive index side dielectric constituting the multilayer dielectric layer and the low refractive index side dielectric of the exit medium.

As is clear from the above equation (1), the larger the number of dielectric layers and the larger the ratio of n ₂ / n ₃ , the larger the reflectance. On the other hand, it is necessary to reduce the number of dielectric layers as much as possible in order to form a pattern with high definition.
For that purpose, a large combination of n ₂ / n ₃ is selected, but the value of the refractive index of the usable dielectric material is 1.
It is almost limited to the range of 3 to 2.3, and an arbitrary combination cannot be obtained.

Further, when applying Max to ablation, it is necessary to consider resistance to excimer laser light, but some literatures such as F. Rainer et al.
As shown in Applied Optics Vol. 24, No. 4 (1985), p. 496 to p. 500, materials having high resistance tend to have a small refractive index. According to the literature, LiF as a strong resistant low refractive index _{material, MgF 2, SiO 2, YF} 3, L
aF ₃ and ThF ₄ are Al ₂ O as high refractive index materials.
₃ , MgO, ThO ₂ , Sc ₂ O ₃ , Y ₂ O ₃ , HfO
_2, etc., but the high-refractive-index materials have lower resistance than the low-refractive-index materials without exception.

Therefore, since the combination of materials is further limited, it is necessary to study the structure of the multilayer film which improves the reflectance as much as possible. FIG. 4 is a schematic sectional view for explaining one example of the basic structure of the dielectric multilayer film mask, FIG. 5 is a schematic sectional view for explaining another example of the basic structure of the dielectric multilayer film mask, and 71 is quartz. Glass substrate, 72 has a high refractive index dielectric layer,
73 is a low refractive index dielectric layer.

In FIG. 4, the incident medium is quartz glass and the emitting medium is air. The incident medium has a refractive index n ₁ of 1.0, the outgoing medium has a refractive index n _e of 1.5, and the refractive index ratio n. _e /
n ₁ is 1.0 / 15 = 0.66. In addition, the incident medium in FIG. 5 is air and the emitting medium is quartz glass, the incident medium has a refractive index n ₂ of 1, and the outgoing medium has a refractive index n _e of 1.
A 5, the refractive index ratio n _e / n ₂ is 1.5 / 1.0 =
It is 1.5.

By comparing the dielectric multilayer film masks shown in FIGS. 4 and 5 above, which structure of the mask is advantageous is determined.
It is clear from the equation (1) that the difference is the value of the refractive index ratio n _e / n ₁ . FIG. 6 is an explanatory diagram showing the relationship between the refractive index ratio n _e / n ₁ and the reflectance corresponding to FIG. 4 with the number of layers as a parameter.

FIG. 7 is an explanatory view showing the relationship between the refractive index ratio n _e / n ₁ and the reflectance corresponding to FIG. 5 with the number of layers as a parameter. The number of layers varies from 1 to 10 layers from bottom to top. Here, the substrate constituting the mask is quartz glass, and the refractive index at a wavelength of 248 nm is 1.5.

In the case of FIG. 7 in which light is incident from the air side, the refractive index ratio n _e / n ₁ is 1.5, while in the case of FIG. It is clear from the figure that the difference can be practically neglected as is increased. However, when the value of n ₂ / n ₃ is not so large and there are 10 layers or less, this difference is remarkable. FIG. 8 is a schematic cross-sectional view for explaining the basic structure of the excimer laser processing mask (exposure mask) according to the present invention. The refractive index n constitutes the mask on the uppermost layer of the multilayer dielectric layer shown in FIG. When _one quarter wavelength film (additional high refractive index layer 4) with n> n ₁ which is larger than the refractive index n ₁ of the incident medium is added, the formula (1) is changed to the following formula (2). The problem of is solved.

R (2N + 1) = {[1- (n ₁ n _e / n ² ) ・ (n ₂ / n ₃ ) ^2N ] / [1+ (n ₁ n _e / n ² ) ・ (n ₂ / n ₃ ) ^2N ]} ² ... (2) Since the additional high refractive index layer 74 is in the final stage of transmitted light, it does not necessarily have strong laser resistance.
A material with a high refractive index can be selected.

FIG. 9 shows the relationship between the refractive index ratio n ₂ / n ₃ and the reflectance of the multilayer dielectric layer when Al ₂ O ₃ is used as an additional high refractive index layer except for the metal film 75 layer of FIG. It is a characteristic explanatory view of. From the figure, it can be seen that the characteristics are improved by adding the high refractive index layer compared to FIG. 6 as well as FIG. 7.

When the dielectric layer mask is actually used, it is difficult to use the conventional alignment optical system or the like because it is almost transparent to ordinary visible light. As a countermeasure, a metal film may be stacked, but the excimer laser resistance of the metal film is low.
0 mJ / cm ² or less of what is most to life of the mask, it is desirable to use at 10 mJ / cm ² following irradiation.

Therefore, in order to use the metal film on the dielectric layer, only the arrangement shown in FIG. 8 is possible. When a metal film is actually superimposed on a dielectric layer, there are many advantages not only in ease of use as a mask but also in manufacturing the mask. As a method for manufacturing a multilayer dielectric multilayer mask, ion milling,
Dry etching and the like are generally used, but the point to be considered is to inspect and modify the resist pattern before milling or etching.

In particular, since it is difficult to repair the multi-layer dielectric layer itself, it is necessary to completely inspect and repair the resist pattern. Currently, C is established in this aspect.
r-mask technology, which can be applied to multi-layer dielectric layer masks. That is, a metal film is formed on a multilayer dielectric layer uniformly formed on a substrate, and after confirming no defect, a pattern is formed by a normal photolithography process.

After the pattern is inspected and corrected for defects to obtain a complete metal film pattern, the pattern of the dielectric layer may be formed by the above etching using this as a resist pattern. By setting the transmission energy density of the dielectric layer lower than the damage threshold of the metal film and leaving the metal film pattern, it is possible to treat the same as a normal exposure or etching mask.

Needless to say, a mask having metal films stacked thereon is suitable for ablation with a low energy density. [Structure for Achieving Sixth Object] An apparatus for manufacturing a liquid crystal display device equipped with an alignment device for aligning an exposure mask and a glass substrate with high accuracy with a simple structure which is the sixth object of the present invention. The configuration is as follows.

(1) In a liquid crystal device in which a predetermined pattern is formed by irradiating an excimer laser beam through an exposure mask on a surface of a resist film formed on a workpiece such as a glass substrate which constitutes a liquid crystal display element through the exposure mask. Alignment marks are formed on a part of the exposure mask, and the substrate is equipped with a substrate that can be positioned and compatible with the workpiece and emits fluorescence at the projection portion of the alignment marks of the exposure mask. It is characterized in that the exposure mask and the object to be processed are aligned based on the location.

(2) In an exposure apparatus that uses excimer laser light through a photomask on the resist film formation surface of a work piece, an alignment mark is formed on the exposure mask and the alignment mark of the exposure mask is formed. A holder that holds the processed substrate while emitting fluorescence in the projection unit,
Means for positioning the substrate to be processed with respect to the holder based on the fluorescent portion of the holder. [Operation of Configuration for Achieving Sixth Purpose] Above (1)
The substrate compatible with the workpiece in the above configuration projects the alignment mark of the exposure mask by the excimer laser light, and emits fluorescence at the projection location.

On the basis of this fluorescence, the alignment mark which is projected and visible on the substrate arranged in positional correspondence with the object to be processed becomes visible, and the alignment effect is exactly the same as the conventional projection of visible light. Can be obtained. Therefore, the alignment of the exposure mask with respect to the workpiece can be achieved with a simple configuration.

Further, according to the above configuration (2), the alignment mark of the exposure mask is projected on the holder for holding the workpiece, and fluorescence is emitted at the projected portion. And
The workpiece held by the holder onto which this alignment mark is projected can be aligned with the holder and the exposure mask on the basis of the fluorescent light emission location of the projection light. [Structure for Achieving the Seventh Objective] (1) Debris generated by ablation processing by excimer laser light forms a laminar flow at the excimer laser irradiation portion (processing portion), or (2) nozzles are arranged. (3) A tubular nozzle or a plurality of tubular nozzles is arranged at the irradiation site, or an annular suction nozzle that surrounds the excimer laser light irradiation area (processing area) is used as an explosion cloud (bloom). Is set and used at a position on the workpiece where the speed of becomes slower than the flow rate of suction, thereby removing by suction.

The debris removing device by suction of the above (3) is a bottom plate having an entrance window made of a quartz material or the like that transmits excimer laser light and an opening facing the entrance window and close to the processing region of the workpiece. And an exhaust port connected to an exhaust system, and a nozzle structure formed between the exhaust port and a space between the entrance window and the bottom plate. The debris removing device according to the above (3) is characterized by including a vacuum suction device at a position facing the ablation processing portion that irradiates the excimer laser light, and sucking and removing the debris generated by the ablation.

Further, the vacuum suction device is provided with at least one tubular nozzle, and the tubular nozzle is installed at a position on the workpiece where the velocity of the plume due to ablation becomes slower than the flow velocity of the vacuum suction. Further, the vacuum suction device is provided with an annular suction nozzle surrounding the ablation processing part, and is installed at a position on the workpiece where the speed of the plume due to ablation becomes slower than the flow speed of the vacuum suction.

Then, an entrance window made of a quartz material that transmits excimer laser light to the vacuum suction device, and a bottom plate having an exit opening that is wider than the area of the ablation processed portion of the workpiece by at least 2 mm and faces the entrance window. A nozzle-like structure having a flow velocity of 25 m / s or more at a portion deviated from the optical path of the excimer laser light between the exhaust port connected to the exhaust system, the space between the entrance window and the bottom plate, and the exhaust port. The bottom plate is installed at a distance of about 1 mm or less from the work piece. [Operation of Configuration for Achieving Seventh Objective] As described above, in the ablation by irradiation of excimer laser light, when the material is irradiated with ultraviolet excimer laser light having a high energy density, the laser light hits the laser light. It is defined as a phenomenon in which the substance in the part where the light is emitted is photolyzed and scattered. In addition,
At this time, the photolysis (decomposition) is in an explosive state, and the debris is scattered as an explosion cloud (bloom).

Therefore, by utilizing this ablation phenomenon, for example, by using a certain pattern as a mask, illuminating this with an excimer laser beam, and forming an image on the surface of the workpiece, the shape as the above mask pattern is obtained. It will be formed on the surface of the surface-treated product. With laser light of wavelengths longer than visible light, the decomposition of substances by irradiation with laser light mainly occurs due to a thermal process (thermal decomposition), but when excimer laser light is used, chemical bonds are generated especially to many organic substances. Is decomposed by a non-thermal process that directly cuts
At present, it is mainly used in the field of ultra-precision machining such as micromachining.

Actually, the processing technique utilizing the ablation phenomenon of excimer laser light can be applied not only to the field of micromachining described above, but also to the thin film forming process in the manufacture of TFT and the like, and the ablation can be performed. Ablation development that can perform the process of exposure and development using conventional photolithography technology at the same time by selecting a suitable reegist material.
Similarly, application to ablation peeling or the like is also considered.

The ablation phenomenon is understood as a kind of explosive phenomenon, as described above, because excimer laser light with a pulse width of 20 to 30 ns photolyzes a substance with a high energy density. FIG. 10 is an explanatory view of the ablation phenomenon, which schematically shows a shadow graph of the ablation phenomenon by the dye laser (pulse width of about 5 ns) delay-synchronized with the pulse of the excimer laser light.
Is the conceptual shape of the behavior of debris generated by irradiation of excimer laser light, 16, 16 'are shock waves,
Reference numeral 17 denotes a workpiece.

The figure shows a novolac resin with a wavelength of 248n.
m, an excimer laser beam having an energy density of 100 mJ / cm ² . First, when the surface of the work piece 17 is irradiated with the excimer laser light, as shown in (a), the debris is lifted in the initial state in which debris is emitted from the irradiation area of the work piece 17 with the excimer laser light 15
a occurs.

The shock wave 16 is formed by debris consisting of the released gas or light fine particles.
The front speed of the shock wave 16 is 0.2-
When the delay time is 0.4 μs or less, the supersonic velocity is about 1.5 km / s, but when it is 1 μs after (b), the shock wave 16 ′ has a normal velocity level.

A high pressure is applied to the inside of the wave front of the shock wave, whereby relatively heavy particles, which are the main constituent of the debris 15b, are suppressed.
Since about 10 μs elapses, the internal pressure suddenly decreases, so that the debris 15 c starts to rise, and as shown in FIG.
Mushroom cloud-shaped plume 15d called so-called plume after s position
Is observed.

The plume 15d is formed like 15e of (e) and 15f of (f) with the passage of time. The rising speed and height of this plume in the air are the same as above under a delay time of 100 μs.
20 m / s and about 3 mm, respectively. When the incident energy density is 300 mJ / cm ² , the rate of ablation is about three times, but the height and ascending speed of the plume are at most about 1.5 times.

The above-mentioned behavior of the ablation phenomenon slightly differs depending on the material to be processed, and there is a change such that a clear cloudy cloud-like plume is not observed. Especially, the quantitative value varies depending on the material. Is 300 mJ /
It is one measure of cm ² or less. That is, by including a vacuum suction device that sucks and removes the debris generated by the ablation at a position facing the ablation processing portion that irradiates the excimer laser light, the debris adheres to the surface of the workpiece, It does not reduce the energy of subsequent laser pulses.

Further, since at least one tubular nozzle is provided and the above-mentioned vacuum suction device is installed at a position on the workpiece where the velocity of the plume due to ablation becomes slower than the flow velocity of vacuum suction, debris can be removed efficiently. can do. Furthermore, by providing an annular suction nozzle that surrounds the ablation processing part, the debris is further improved by installing the above vacuum suction device at a position on the workpiece where the speed of the plume due to ablation becomes slower than the flow speed of vacuum suction. Efficiently removed.

Then, the above vacuum suction device is provided with a bottom plate having an entrance window made of a quartz material which transmits excimer laser light and an exit port which is wider than the area of the ablation processed part of the workpiece by at least about 2 mm and faces the entrance window. And a discharge port connected to the exhaust system, and a flow velocity of 25 m / s or more at a portion deviated from the optical path of the excimer laser light between the space between the entrance window and the bottom plate and the discharge port. By providing the structure and installing the bottom plate at a distance of about 1 mm or less from the workpiece, the debris can be removed more efficiently.

[0104]

Embodiments of the present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 11 is a plan view illustrating a configuration in the vicinity of one pixel of an active matrix type color liquid crystal display device to which the present invention is applied. As shown in the figure, each pixel has two adjacent scanning signal lines (gate signal lines or horizontal signal lines) GL (gate lines) and two adjacent video signal lines (drain signal lines or vertical signal lines). The line) is arranged in an intersecting region with the DL (data line) (in a region surrounded by four signal lines).

Each pixel has a thin film transistor TFT (TFT
1, TFT2), a transparent pixel electrode ITO1 and a storage capacitor element Cadd (additional capacitor). The scanning signal lines GL extend in the left-right direction in the figure, and a plurality of scanning signal lines GL are arranged in the up-down direction. Further, the video signal lines DL extend in the vertical direction and a plurality of video signal lines DL are arranged in the horizontal direction. SD1 is a source electrode, SD2 is a drain electrode, BM is a black matrix, and FIL is a color filter.

FIG. 12 is a sectional view of an essential part taken along line 3-3 of FIG. 11, showing a thin film transistor T on the lower transparent glass substrate SUB1 side based on the liquid crystal layer LC.
An FT and a transparent pixel electrode ITO1 are formed, and a color filter FIL and a light shielding film, that is, a black matrix BM are formed on the upper transparent glass substrate SUB2 side.
This upper transparent glass substrate is generally called a color filter substrate.

Silicon oxide films SIO formed by dipping or the like are provided on both surfaces of the transparent glass substrates SUB1 and SUB2. Upper transparent glass substrate SUB2
The black matrix BM, the color filter FIL, the protective film PSV2, the common transparent pixel electrode ITO2 (COM), and the upper alignment film OR are provided on the inner surface (liquid crystal layer LC side) of the
I2 are sequentially provided.

In the conventional method of manufacturing a color filter for a liquid crystal display element, a material having a developing function is exposed and developed except for a portion forming a black matrix BM with a metal film of Cr or the like, and also having a developing function. When a material that does not exist is used, pattern formation is performed by means such as lift-off.
On the other hand, in the present invention, the patterning of each thin film of the lower transparent glass substrate SUB1 and the color filter FIL and the upper transparent glass substrate SUB2 on which the light-shielding film, that is, the black matrix BM forming the liquid crystal display element is formed,
A high-precision liquid crystal display device can be manufactured by forming it by processing utilizing the ablation phenomenon of excimer laser light.

FIGS. 13, 14 and 15 are explanatory views of a forming process by patterning a thin film multilayer structure which constitutes a TFT on a lower transparent glass substrate. In each figure, the first
Photo, second photo,... Show an integrated exposure / development process according to the present invention in which a resist film is applied to cover the thin film to be processed, and this is irradiated with excimer laser light through an exposure mask. Also, the left side of each figure is a TFT part in FIG. 12, the right side is a terminal lead-out part, and the center is a description of the process.

Step A (FIG. 13) First, a silicon oxide film SIO is formed on both surfaces of a lower transparent glass substrate SUB1 made of 7059 glass (trade name) by dipping, and then baking is performed at 500 ° C. for 60 minutes. A first conductive film g1 made of chromium having a film thickness of 1100 ° is formed on the lower transparent glass substrate SUB1 by sputtering, a resist is coated thereon, and a first photo process using excimer laser light is performed. A resist pattern is formed.

Next, the first conductive film g1 is selectively wet-etched with a solution of cerium ammonium nitrate as an etching solution. Thereby, the gate terminal GTM,
An anodized bus line SHg for connecting the drain terminal DTM and the gate terminal GTM, a bus line SHd for short-circuiting the drain terminal DTM, and an anodized pad (not shown) connected to the anodized bus line SHg are formed.

Step B (FIG. 13) Al-Pd, Al-Si, Al-S having a film thickness of 2800Å
The second conductive film g2 made of i-Ti, Al-Si-Cu, or the like
Is formed by sputtering. Apply resist,
A second photo process using excimer laser light is performed to form a resist pattern.

Next, the second conductive film g2 is selectively etched with phosphoric acid, nitric acid and glacial acetic acid. Step C (FIG. 13) Then, a third photo step of the anodic oxidation mask AO is performed to form a resist pattern. Next, the substrate SUB1 was immersed in an anodic oxidation solution consisting of a solution in which 3% tartaric acid was adjusted to pH 6.25 ± 0.05 with ammonia and diluted 1: 9 with an ethylene glycol solution. It is adjusted to be 0.5 mA / cm ² (constant current formation).

Next, anodization is performed until the formation voltage of 125 V required to obtain Al ₂ O ₃ having a predetermined film thickness is reached. After that, it is desirable to hold this state for several tens of minutes (constant voltage formation). This is important for obtaining a uniform Al ₂ O ₃ film. Thereby, the second conductive film g2
Is anodized to form an anodic oxide film AO having a thickness of 1800 ° on the scanning signal line GL, the gate electrode GT, and the electrode PL1.
F is formed.

Step D (FIG. 14) Ammonia gas, silane gas, and nitrogen gas were introduced into the plasma CVD apparatus to form a 2000 Å-thickness Si nitride film, and silane gas and hydrogen gas were introduced into the plasma CVD apparatus. After forming an i-type amorphous Si film having a film thickness of 2000Å, hydrogen gas and phosphine gas are introduced into the plasma CVD apparatus to form an N (+) type amorphous Si film having a film thickness of 300Å. .

Step E (FIG. 14) A resist is applied, and a fourth photo step using excimer laser light is performed to form a resist pattern. Next, an island of the i-type semiconductor layer AS is formed by selectively etching the N (+)-type amorphous Si film using SF ₆ and CCl ₄ as a dry etching gas.

Step F (FIG. 14) A resist is applied and a fifth photo step using excimer laser light is performed to form a resist pattern. Next, the Si nitride film is selectively etched using SF ₆ as a dry etching gas. Step G (FIG. 15) A first conductive film d1 made of an ITO film having a film thickness of 1400 Å is sputtered, a resist is applied, and a sixth photo step using excimer laser light is performed to form a resist pattern. Next, the first conductive film d1 is selectively etched using a mixed solution of hydrochloric acid and nitric acid as an etching solution to form the uppermost layer of the gate terminal GTM and the drain terminal DTM and the transparent pixel electrode ITO1.

Step H (FIG. 15) A second conductive film d2 made of Cr and having a film thickness of 600 Å is formed by sputtering.
Pd, Al-Si, Al-Si-Ti, Al-Si-C
A third conductive film g3 made of u or the like is formed by sputtering. A resist is applied, and a seventh photo process using excimer laser light is performed to form a resist pattern.

The third conductive film g3 is etched by using the same liquid as the process B, and the second conductive film d2 is etched by using the same liquid as the process A, so that the video signal line DL and the source electrode SD1 are formed. The drain electrode SD2 is formed. Next, CCl ₄ and SF ₆ are introduced into the dry etching apparatus to
The N (+) type semiconductor layer d0 between the source and the drain is selectively removed by etching the (+) type amorphous Si film.

Step I (FIG. 15) Ammonia gas, silane gas, and nitrogen gas are introduced into the plasma CVD apparatus to form a Si nitride film having a thickness of 1 μm. A resist is applied, and an eighth photo process using excimer laser light is performed to form a resist pattern.
Next, the protective film PSV1 is formed by selectively etching the Si nitride film by a photolithography technique using SF ₆ as a dry etching gas.

As described above, wet etching is used for etching the metal film, and dry etching is used for etching the semiconductor film and the insulating film. The peeling of the resist film after each photo step is performed by irradiating the entire surface with excimer laser light with a narrowed energy, and the conventional wet treatment using a peeling material is not performed.

Similarly, the thin film processing of the substrate PSV2 on the color filter side is also performed by applying a black mask material and a color filter material and a photo process using excimer laser light using an exposure mask. Thus, according to the present invention,
Since no liquid is used for developing and stripping the resist, the process can be simplified and the influence on the environment can be eliminated, and each substrate of the liquid crystal display element can be manufactured at low cost.

Next, exposure / excitation using excimer laser light
An embodiment of the developing device will be described. FIG. 16 is a schematic view for explaining the outline of an optical system of an exposure machine used in the method for manufacturing a liquid crystal display element according to the present invention, where 1 is an excimer laser and 2
Is an illumination optical system, 2'is a reflection mirror, 11a is an XY mask table, 8 is an imaging lens system, 11b is an XY substrate table, 7 is an exposure mask (however, the multilayer film surface is on the lower side), 1
0 is a substrate.

The excimer laser 1 as an exposure light source oscillates a laser beam having a wavelength of 308 nm and an output of 800 mJ at a repetition frequency of 350 Hz. The illumination optical system 2 is a homogenizer optical system that shapes a beam profile so as to have a uniform intensity distribution within a given shape. The illumination optical system 2 uses an exposure mask 7 installed on an XY mask table 11a via a mirror 2 ′. Light up.

The exposure mask 7 is a dielectric multi-layer film mask, and the exposure mask 7 is exposed to, for example, 4
Illuminate in the form of a slit of mm × 90 mm. The imaging lens system 8 is composed of a 1: 1 telecentric symmetrical lens, has an aperture of 120 mmφ and NA = 0.1, and projects the aperture pattern image of the exposure mask 7 onto the substrate 10 placed on the XY substrate table 6. . Due to the configuration of the imaging lens system 8, the opening pattern of the exposure mask 7 and the image on the substrate 10 have a mirror image relationship.

The maximum length of the XY substrate table 11b is 900 m.
A substrate having a size of mx 700 mm can be mounted. Also, X-
Y mask table 11a is up to 650mm x 650mm
An exposure mask having a size (650 square) can be mounted. In this embodiment, a pixel pitch of 0.12 mm and a glass substrate of 800 mm × 450 mm size are used.
TFT having a display unit of 024 × (1920 × 3) pixels
Layers made up. The area of the display is 368.64 mm x 69
1.2mm or 31 inches diagonal 78.7cm
It is.

A concrete embodiment of this exposure / developing apparatus is shown in FIG. Since the area of the output light of the excimer laser is small, the irradiation light to the exposure mask is formed in a slit shape, and the exposure mask and the glass substrate are relatively moved to complete the entire display area. Most of the actual display surface is a repeated portion of a pixel, and a unit of division is divided by this unit.

FIG. 17 is an explanatory view of the principle of dividing the substrate pattern for the step-scan exposure mask in the liquid crystal display device manufacturing method of the present invention. 10 is a glass substrate, 10a is a pixel portion, and 10b and 10c. Is the terminal part, ~
Indicates a divided area. Here, each divided area on the substrate side,
, Consist of the same repeating pattern, and
0a and upper and lower terminal portions 10c and 10c '.
In addition, the divided region is the pattern 10 near the left terminal portion.
b, the divided area is the pattern 10 near the terminal portion on the right side.
b '.

FIG. 18 is a plan view for schematically explaining a constitutional example of an exposure mask used in the method for manufacturing a liquid crystal display element according to the present invention, as viewed from the multilayer film surface side of the exposure mask. In the figure, 7 is an exposure mask, and in this embodiment, three types of opening patterns are formed. That is, the first opening pattern portion is a portion where the opening pattern 7a corresponding to the pixel portion 10a and the opening patterns 7c and 7c 'corresponding to the upper and lower terminal portions 10c and 10c' are combined. The same pattern is shifted three times in the Y-axis direction in accordance with the area, and the exposure is repeated three times.

The second opening pattern portion is the opening pattern 7b portion corresponding to the pattern 10b near the terminal portion and the third opening pattern portion 3b.
Of the opening pattern portion is a pattern 10b 'near the terminal portion.
Is formed on a quartz substrate. Reference numeral 12a denotes an excimer laser light in a state of irradiating the first opening pattern portion, 12b denotes an excimer laser light in a state of irradiating the second opening pattern portion, and 12c denotes the third opening pattern portion. The excimer laser light in the irradiated state is shown for each exposure region for the sake of clarity, but these excimer laser lights are fixed. Also, 7d, 7d 'as light-shielding portions SH,
7e and 7e 'are formed.

Light-shielding pattern portion (SH portion) of the exposure mask
Means that 1 / of the oxide films HfO ₂ and SiO ₂
A multilayer film made of four wavelength (λ / 4) films
The vertical reflectance at 08 nm is set to 70% or more. The opening pattern portion of the exposure mask through which the excimer laser light passes is a portion where this multilayer film is removed by dry etching.

In the present example, in consideration of the shortening of the exposure step time and the connecting accuracy of the repeated pattern portion, the scanning in the X direction is not repeated, and therefore, a large size which is almost equal to the width of the display portion in the X direction on the substrate is used. The exposure mask 7 was used. However, when the display area becomes larger, the opening pattern 7b of the terminal portion formed on the exposure mask 7,
7b ′ is an integral fraction of the size of the divided area of the substrate in FIG. 17 and the X direction, and the opening pattern 7a of the pixel portion is an integral fraction of the divided area in the X and Y directions. Aperture patterns 7a, 7b, 7b ', 7
It is also possible to form five types of pattern portions of c and 7c ′, form a boundary portion with a light shielding SH portion, and shift in the X direction and the Y direction to form a resist pattern of a large substrate.

The excimer laser beams 12a, 12b, 12c for irradiating the exposure mask 7 are fixed in the form of long slits in the direction orthogonal to the relative movement direction (arrow X) of the exposure mask and the substrate. By moving the exposure mask and the substrate relative to each other, the entire surface of the substrate is scanned to pattern the resist. At this time, the pattern of the exposure mask 7 is imaged as a mirror image of the Y axis on the glass substrate 10 by the imaging lens. Further, upon exposure, the multilayer film surface on which the pattern of the exposure mask 7 is formed is arranged so as to face the pattern formation surface of the glass substrate 10.

Therefore, at the time of forming the resist pattern in the divided areas of FIG. 17, after the exposure mask 7 is turned upside down with respect to the Y axis, the start portion B at the upper left of the exposure mask has the stationary imaging lens as the origin. With respect to the Y axis, the initial setting is made at a position where a mirror image is formed on the upper left of the corresponding glass substrate 10. The exposure mask 7 and the glass substrate 10 are scanned in the X direction at the same speed v in opposite directions with respect to the stationary imaging lens. Here, the speed v is as follows: v = df / n n: the number of shots in which the resist is ablated f: the repetition frequency of the laser (shots / second) d: the width of the slit (X direction, short width) (cm) v: Scan speed (cm / sec).

That is, the scan start position indicated by the start portion B at the upper left starts from a position outside the pattern, and X
The repetition of the scan in the direction is not performed, but the scan is performed up to the position C where the resist pattern formation of the divided area is completed in one scan. There is a fixed relationship between the scan speed (v) and the ablation rate, and it is necessary to scan at an optimum speed in consideration of the resist film thickness and the material.

As a result, the resist in all areas of the substrate is exposed to a predetermined pattern, and the pattern of the exposure mask is developed and removed by ablation of excimer laser light. In the above description, excimer laser light is used only for removing the resist, but the thin film underneath can be ablated at the same time as the removal of the resist, whereby the thin film can be subjected to predetermined patterning.

Next, an embodiment of the method of manufacturing a liquid crystal display element according to the present invention will be described. [Example 1] 270 mm length x 200 mm width, thickness 1.1
A TFT type liquid crystal display device was manufactured using a glass substrate of mm. The TFT pattern is a so-called VGA with 640 × 480 pixels, and the pixel pitch is 0.33 mm.

The three colors of R, G and B are vertical stripes, and therefore the dot pitch in the horizontal direction is 0.11. The overall layout of the screen is as shown in FIG.
It consists of a screen area of 158.4 mm and a peripheral terminal area, and the entire pattern area, that is, the area of step-scan is about 225 mm x 185 mm. The exposure mask corresponding to the one obtained by dividing the pixel region into three equal parts and dividing the gate terminal side and the liquid crystal filling side into one region is shown in FIG.
As shown in FIG. 3, it consists of three types of opening patterns. The horizontal width of the pixel area 7a is 70.4 mm and includes 640 dots.

The excimer laser having a wavelength of 248 nm was used as a light source, and the illumination light for the exposure mask was in a slit shape of 5 mm × 75 mm. The imaging lens is a telecentric symmetric lens. A. (Numerical aperture) is 0.2. The energy density on the glass substrate surface is 100 mJ / cm ² . The scan distance is 185 mm, and five horizontal movements are performed.

An imide resin was used as the material for the resist film. The ablation rate in this case is 0.05 μm / sho for an energy density of 100 mJ / cm ² .
t. The resist film was exposed to the above-described excimer laser light, and a TFT substrate and a color filter substrate were formed, a liquid crystal layer was sealed, a driving IC was mounted, and a backlight was assembled, thereby completing a liquid crystal display device.

With the liquid crystal display device thus completed, high quality image display could be obtained. Example 2 A melamine resin was used as a resist film instead of the imide resin used in Example 1. In this case, 10
0.04 μm / sh at an energy density of 0 mJ / cm ²
Processing at an ablation rate of ot, creating a TFT substrate, a color filter substrate, encapsulating a liquid crystal layer, and driving I
A liquid crystal display device was completed by mounting C and incorporating a backlight.

With the liquid crystal display device thus completed, similar high quality image display could be obtained. Example 3 Instead of the melamine resin used in Example 2, an epoxy resin was used as a resist film. In this case, 1
0.045 μm / at an energy density of 00 mJ / cm ²
A liquid crystal display device was completed by processing at a shot ablation rate, forming a TFT substrate, a color filter substrate, encapsulating a liquid crystal layer, mounting a driving IC, and incorporating a backlight.

With the liquid crystal display device completed in this way, high quality image display could be obtained as in the above embodiment. Next, the exposure apparatus (ablation developing machine) used in the method of manufacturing the liquid crystal display element of the present invention described with reference to FIG. 3 will be described in detail. FIG. 19 is a principle diagram for explaining the division of excimer laser light by a lens array in an ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention, in which an excimer laser parallelized to a pair of lens arrays 4a and 4b. By injecting the light beam 3a, dividing the light beam area, and arranging the condensing portion in the space between the lens arrays 4a and 4b,
The optical parts (lens arrays 4a and 4b) are prevented from being damaged.

FIG. 20 is an explanatory view of the illumination optical system of the ablation developing machine used in the method of manufacturing the liquid crystal display element of the present invention, which is the lens array 4a, 4b, followed by the division of the light source described in FIG. Each light flux of the excimer laser light incident from the lens array 4b by the lens 5a and the lens 6a uniformly illuminates the surface of the exposure mask 7a.
An image is formed on the entrance pupil 9a of the imaging lens.

Generally, the energy space distribution of the light beam of the excimer laser, that is, the beam profile of the light beam exhibits a distribution close to a Gaussian distribution. FIG. 21 is an explanatory view of making uniform the illumination light of the exposure mask of the ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention. As shown in FIG. 21A, the center of the distribution, that is, the light of the excimer laser. If the beams are divided so that they are symmetric with respect to the optical axis of the beam and the dividing portions are substantially straight lines, they can be symmetrically overlapped on the reticle surface by the condensing lens as shown in FIG. That is, in the case of a beam profile symmetric with respect to the central axis, it is advantageous that the number of lens arrays in FIG. 19 is an even number and the optical axis passes through the center.

Further, in general, the beam profile of the excimer laser light is not square, and the irradiation area to the reticle is not always square, so that the dividing lens shown in FIG. 19 is not a simple spherical lens. That is,
The shapes of the illumination lenses 4 to 6 shown in FIG. 20 are determined by the illumination shape on the reticle, the position of the entrance pupil of the imaging lens, and the distance between the laser light source and the exposure mask.

Particularly, when the shape of the illumination light on the reticle surface is rectangular, the illumination optical system can be divided into independent optical systems which are orthogonal to each other. In this case, the cost is reduced and the adjustment is simplified by using the cylindrical lens as the individual lens. However, since the lens 6a shown in FIG. 20 is inevitably close to the surface of the exposure mask, it may be convenient to combine the two lenses separated by the orthogonal optical system into one as described above.

Further, when a wavelength of 248 nm or less is used, the substance generated by the interaction between the ultraviolet light and the atmospheric substance may adhere to the lens surface to reduce the transmittance. To avoid this, it is effective to house the illumination optical system in a container in a nitrogen atmosphere. In this way, it is better to use as few lenses as possible. This point should be determined from cost performance.

If the focusing of the excimer laser light is prevented from hitting the optical parts, the structure of the imaging lens will be limited. Methods that have been conventionally studied as one-to-one (1: 1) imaging lenses for excimer laser light include Offner and Wyne-Dyson.
Dyson), a telecentric symmetric lens, and the like. The former two have a complicated structure due to a combination of a reflection and a refraction system, but the aberration is easily controlled.

On the other hand, since the symmetrical lens has a simple structure and the light collecting surface is in the space, the constituent lenses are not damaged. However, in the case of a symmetrical lens, an attempt to increase the aperture increases the cost, and a method for forming a large area pattern becomes a problem. In the present invention, as a method for forming a large-area pattern, a method is used in which a one-to-one exposure mask, a symmetrical lens, and rectangular illumination are used to relatively move and scan the exposure mask and a workpiece such as a color filter substrate. It is a thing.

FIG. 22 is a schematic view for explaining the scanning system of the ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention, which is on the exposure mask and the workpiece (glass substrate) on which the illumination area 10a is fixed. Is considered to be moved, the scanning may be performed by alternately changing the moving direction or moving in the same direction. However, the former requires a shorter processing time.

The essential problem in such a scanning system is
This is the area where the illumination lights overlap. It goes without saying that even if the overlap slightly shifts, if the length of the illumination area is long, it can be clearly recognized visually. The shift in the overlapping area can be considered to be caused by two factors: mechanical fluctuation in scanning and image distortion due to the optical system. For the former, high precision X-
Although it is possible to take measures by using the Y table, it is difficult to make a lens without aberration for the latter, so it is necessary to take other measures.

FIG. 23 is an explanatory view of an example of the position setting of the illumination area in the scanning of the ablation developing machine used in the method of manufacturing the liquid crystal display element of the present invention, in which the knife edge 12 is placed directly above the exposure mask 7 The end portion is set to be located exactly in the middle of the repeating pattern 7b. As a result, the end portions of the incident light 7a overlap with each other in the repeated pattern 7b, so that the processed pattern is not affected even if the overlap is shifted.

An exposure mask having a belt-shaped pattern may be used instead of the knife edge. Blurred edges
In geometrical optics, it depends on the displacement of the object position and the depth of focus of the imaging lens. However, if the imaging lens is made telecentric, the size of the image does not change and only the end is blurred. The blur amount is bNAδ _a /
It is given by (fa). Here, a is the object point distance, b is the image point distance, f is the focal length, and NA is the lens lens distance. A. , Δ
_a is the amount of deviation from the exposure mask surface such as the knife edge.

For a 1: 1 lens, since b / a = 1, the above equation becomes NAδ _a / f, and as an example, NA = 0.
If 1, δ _a = 10 mm and f = 200 mm, the blur amount is 5 μm. Since the mechanical accuracy in setting the knife edge or the like can be in the order of μm, it is sufficiently possible to set the knife edge or the like in the pattern photoconductor in the case of the TFT level pattern accuracy and the repeated pattern shape.

According to the above method, even if there is no overlap in the pattern area of the illumination area, a linear pattern is visually recognized if the aberrations at the periphery of the imaging lens are significantly different. Therefore, it is important that aberrations at least in one direction at the lens diameter, particularly in the peripheral portion, have the same shape. FIG. 24 is an explanatory diagram of the overall configuration of an ablation developing device used in the method of manufacturing a liquid crystal display device of the present invention, which is installed in a room having different cleanliness in which an excimer laser light source unit of the ablation developing device and a developing optical system are separated by a separating wall. The so-called through-the-wall ablation in which the laser light beam emitted from the light source unit 20 made of an excimer laser (ultraviolet light pulse laser) is introduced into the ablation developing unit 22 through the transmission window plate 24 provided in the separation wall 21. It is a developing machine.

As shown in the figure, the light source section 20 and the developing section 22 including the exposure optical system are separated, and the laser light beam emitted from the light source section 20 is introduced into the ablation developing section 22 through the transmission window plate 24. At this time, in order to prevent the reduction of the energy of the laser light, it is desirable that the reflection by the mirror is performed only once as shown in the figure.

Also, in order to prevent vibration, the light source section 20
And the developing unit 22 are installed on a vibration isolation table 23. Further, in addition to the vibration isolation table 23 or instead of the vibration isolation table, the transmission window plate 24 is used for relative vibration of the laser light beam and the development optical system including the illumination optical system 22a and the imaging optical system 22b. By tilting correspondingly, the deviation of the laser light beam caused by the vibration can be corrected.

FIG. 25 is an explanatory view of a deviation correction method for moving the optical axis in parallel by inclining the transmission window plate through which the laser light beam of the ablation developing machine used in the manufacturing method of the liquid crystal display device of the present invention. , Transparent window plate 24
Where D is the thickness, n is the refractive index, and θ is the inclination of the transmission window, the deviation d of the laser beam is Dθ (1-1 / n).
Becomes

Of the relative deviations of the light beam from the laser light source, the deviation in the longitudinal direction of the illumination area is essential, and therefore only this should be taken practically. That is, only the shift component in this direction is displayed, and the above shift can be corrected by changing the inclination of the transmission window plate 24 by the servo mechanism. With the above description and the respective configurations of the present invention, it is possible to perform pattern processing with a large area and high definition utilizing the ablation phenomenon of an ultraviolet pulsed laser.

Examples of the ablation developing machine used in the method for producing a liquid crystal display device of the present invention will be described more specifically below. [Embodiment 4] FIG. 26 is a schematic diagram of the structure of an exposure optical system of an ablation developing machine for explaining a fourth embodiment of the present invention. The same parts as those in FIG. 3 are designated by the same reference numerals. .

In this embodiment, KrF (wavelength 2) is used as the light source.
An excimer laser having a repetition frequency of 250 Hz and an output energy density of 600 mJ / cm ² is used. The exposure optical system has a lens system arrangement as shown in the figure, and the illumination lens system is an independent system in the X direction and the Y direction in order to obtain slit-shaped illumination light.

The illumination optical system is as shown in FIG. 20, and 4X and 4Y represent the lens 4 in the X direction and the lens 4 in the Y direction, respectively. Hereinafter, 4X ', 4Y', 5Y, 5Y, 6
The same applies to X and 6Y. Further, FIG. 27 is a schematic diagram for explaining an arrangement example of the cylindrical lenses used for dividing the light source in the present embodiment in the X direction and the Y direction.

In the figure, (a) shows the arrangement direction of the cylindrical lens in the X-axis direction, (b) shows the arrangement direction of the cylindrical lens in the Y direction, and (a) and (b) are arranged orthogonally. These lenses 4X and 4Y are bonded by an optical contact. To reduce energy loss, all lenses are AR coated to ensure a transmission of 99% or more.

With this illumination optical system, the maximum illumination area on the exposure mask surface is 80 mm × 2 mm. The distribution of the energy density within this area is ± 5% or less. The length of the slit of the illumination light is adjusted by the blade, and the rise of the energy distribution at the end is 20 μm. As the exposure mask, a 1/4 λ film of SiO ₂ and HfO _{2 which} is patterned by RIE (reactive ion etching) is used. The substrate size of this exposure mask is 300 m
The size is m × 225 mm, and the thickness is 5 mm.

FIG. 28 shows a black matrix (BM) formed on the glass substrate of the color filter of the liquid crystal display device as an example of the opening pattern of the exposure mask in this embodiment.
It is explanatory drawing of the example of a pattern and the arrangement | positioning relationship of the blade for slit illumination. The pitch of the opening portions 7c of the opening pattern formed on the exposure mask 7 for BM pattern development is 0.33 mm × 0.11 mm, the long side of the illumination area is 52.8 mm, and the end 12a of the blade 12 is The blade position is adjusted so as to be within the minimum width of the opening pattern 7c in the longitudinal direction. The above minimum width is 72 μm, and adjustment of the blade position is easy.

As the BM forming material, a material in which carbon black is dispersed in a matrix mainly composed of a polyimide-based polymer is used. The ablation rate of this material is 3
0.1 μm / shot for an excimer laser light input of 00 mJ / cm ² . The coating thickness is 1.2
15sho per μm per site (per unit development area)
When excimer laser light of t is applied, the actual time of ablation is 19 seconds, and the time required for lateral site movement, alignment of the exposure mask, etc. is about 30 seconds plus 1 hour.
0.4 inch display color filter substrate B
M can be processed. [Embodiment 5] FIG. 29 is a schematic diagram of patterning by ablation development of a color filter for explaining a fifth embodiment of the present invention.

In this embodiment, the same apparatus structure as that of the above-mentioned embodiment is used, and the color filters R, G and B in the vertical stripe pattern are subjected to ablation development using the exposure mask shown in FIG. It is a thing. In the figure, 13 is a color filter substrate of a liquid crystal panel, 14a is a first color filter, and 14b is a second color filter resist layer.

When forming this color filter, the length of the illumination area slit set by the blade 12 is set to 70.4 mm.
And the end of the blade 12 is a light shielding portion 7a of the exposure mask 7.
Then, the incident light 7a from the excimer laser is irradiated and the first color filter 14a is ablated and developed. After that, the second color filter resist layer 14b is applied, and the exposure mask 7 is moved by the filter pitch to perform ablation development. Less than,
Similarly, the third color filter is developed to form a liquid crystal panel color filter. In addition, here, BM
Is omitted.

This makes it possible to form color filters of three colors on the color filter substrate of the liquid crystal panel by a dry method. [Sixth Embodiment] In this embodiment, the ablation developing machine of the fourth embodiment is used, and a resist pattern for each layer of the TFT substrate is formed using the resist material for ablation, and etching and ablation of the resist by excimer laser light are performed. The pattern of each layer is formed by peeling by development.

As a result, a required TFT layer can be formed on the TFT substrate of the liquid crystal panel. Next, an example of ablation development by step-scan using the exposure mask according to the present invention will be described. As described above with reference to FIG. 18, the size of the exposure mask is significantly reduced, but the joint portion of the divided portions in step-scan may affect the display performance. In the present invention, this is essential. It is not a problem, but a mechanical precision problem of the XY table. Particularly, in the case of manufacturing a liquid crystal display element, a slight shift is corrected by the light shielding portion. Therefore, it is important to accurately form the light-shielding portion.

FIG. 30 is an explanatory view of a preferable dividing line of the exposure mask of the ablation exposure machine used in the method of manufacturing a liquid crystal display device according to the present invention, and FIG. Part (SH), 81 is an opening pattern, and 82 and 83 are dividing lines. As shown in FIGS. 30A and 30B, the dividing line of the exposure mask is located at a position passing over the light shielding portion 80 between the adjacent opening patterns 81.
Opening pattern 81 as shown in FIGS. 31 (a) and 31 (b)
Misalignment during exposure is less noticeable than when the position passes above.

Incidentally, such a dividing method can be applied not only to the lithography using the ablation phenomenon of the excimer laser, but also to the ordinary photolithography using the high pressure mercury lamp as the light source. In this case, not only the 1: 1 refraction-type symmetric lens but also a small mirror projection type can be used as the imaging lens, so that the cost of the exposure apparatus can be significantly reduced. Especially, since the XY mask table can be kept constant regardless of the size of the glass substrate, the device cost can be further reduced.

The mechanical time loss due to step-scan exposure can be covered by increasing the irradiation intensity and the speed of each table. Further, in the present invention, since the step operation requires a mechanical time, the single wafer type is more advantageous than the multi-cavity production, and the exposure mask and the XY substrate table are allowed to have a little margin, It is good to have a dedicated machine that can handle a certain center size and the size of the board before and after this. However, the only part to change is the table,
The optical system is common.

The method of forming the resist pattern will be described in more detail below with reference to the drawings. [Embodiment 7] FIG. 32 is a schematic view for explaining an example of division of a substrate for explaining an embodiment of a method for forming a resist pattern in a method for manufacturing a liquid crystal display element according to the present invention, and 10 is a glass constituting the liquid crystal display element. Substrate, 10A is a pixel portion, 1
Reference numeral 0B is a left and right terminal portion and 10C is an upper and lower terminal portion.

The glass substrate in the figure is 450 m in length (X direction).
m, horizontal (Y direction) 800mm substrate size, vertical 36
The pixel section 10A has a size of 8.64 mm and a width of 691.2 mm. In the present embodiment, in order to perform the step-scan exposure, the pixel portion of the glass substrate 10 is divided into eight equal parts in the vertical direction, and each divided pixel portion to one is made into one unit, which is circled in the figure. And 10 are 1 unit each. The width of each unit is a size that can be covered by the slit of the excimer laser beam.

FIG. 33 is a plan view for explaining a specific example of the exposure mask used in this embodiment. The overall size is 420 mm in the vertical direction (X direction) and 280 in the horizontal direction (Y direction).
mm. The size of the opening pattern in the vertical direction (X direction) of the exposure mask 7 is the same as the size in the vertical direction (X direction) of FIG. 32, and the size of the pixel portion opening pattern 7a in the vertical direction is 36.
The horizontal (Y direction) is 86.4 mm obtained by dividing the pixel portion into eight equal parts.

Further, the horizontal size of the left and right terminal portion opening patterns 7b is 10 mm, and the vertical size is 368.64+.
(10 × 2) = 388.64 mm, the vertical size of the upper and lower terminal portion opening pattern 7c is 10 mm, and the horizontal size is 86.4 mm, which is the same as the pixel portion 7a. Then, light-shielding portions 7d, 7d ′ for avoiding damage due to excimer laser light are provided between the pixel portion opening pattern and the left and right terminal portion opening pattern 7b and outside the left and right terminal portion opening pattern 7d.
7e and 7e 'are formed.

In the figure, 12a shows the irradiation state of the slit-shaped excimer laser light, and the chrome film 7d,
7d '. Although the illustrated excimer laser beam is irradiating the pixel opening pattern 7a, the end portions of the excimer laser light are similarly shielded from the light-shielding SH portions 7d and 7d when the terminal opening pattern 7b is irradiated.
e.

The light-shielding portion 7e arranged outside the terminal portion opening pattern 7b is wide because the exposure mask 7 is provided.
This is to prevent the excimer laser beam deviating from the exposure mask from ablating the XY mask table and generating dust when the is mounted on the XY mask table. FIG. 34 is an explanatory view of the irradiation state of the excimer laser light on the resist on the glass substrate through the exposure mask,
(A) is a perspective view of a main part, and (b) is a cross-sectional view of the main part of the exposure mask, showing a state where the pixel portion of the exposure mask 7 is exposed.

In the figure, 1a is an excimer laser beam, 71 is a quartz glass substrate, 7'is a dielectric multilayer film, and 7a.
Is a pixel portion pattern, 7b is a terminal portion pattern, 70 is an opening pattern, 8 is an imaging lens, 12 is a resist film, 12a
Is a resist pattern. The slit-shaped excimer laser beam 1a resists the image of the opening pattern 70 of the exposure mask 7 through the imaging lens 8 as the exposure mask 7 and the resist film 12 on the glass substrate move relatively in the direction of arrow v. The film 12 is irradiated and the resist pattern 12a is formed by the ablation phenomenon.

At this time, it is possible to remove the lower thin film by ablation at the same time as the ablation of the resist film. After forming a resist pattern and performing a required etching process, the unnecessary residual resist film can be removed by irradiation of the entire surface with excimer laser light.

As described above, the exposure mask of this embodiment has an area which is 1/3 that of the conventional 1: 1 mask, and the manufacturing cost of the exposure mask is significantly reduced. The ablation resist used here completes ablation by irradiation with 10 times (10 shot / site) at an energy density of 100 mJ / cm ² . The scan area is 400 mm, and the patterning of the entire substrate is completed by 10 scans as described above. Therefore, the scan time is 28.6 seconds, the stepping time for 10 times is 10 seconds, and the time required for carrying, desorption, and alignment of the substrate and the exposure mask is added, and a 31-inch diagonal TFT substrate can be obtained with a takt time of about 45 seconds. completed.
Next, an embodiment of a method for manufacturing an exposure mask according to the present invention will be described.

The exposure mask has three dielectric layers each consisting of a pair of a photorefractive index layer and a low refractive index layer (that is, the total number of film forming materials having a high refractive index and a low refractive index is 6), HfO ₂ is used as an additional high refractive index layer, and the thickness of the metal film is 100 nm.
Of Cr. At this time, the transmittance of the dielectric layer is about 10%.
Therefore, Cr (crosium) showed sufficient resistance to the incident energy density on the mask surface of 400 mJ / cm ² . [Embodiment 8] FIG. 35 shows a combination of a high-refractive index layer material and a low-refractive index layer material which are materials for an exposure mask of an excimer laser exposure machine used for manufacturing a liquid crystal display device according to the present invention, and a transmittance of 10% or less. It is explanatory drawing of the minimum number of layers.

In the present embodiment, in the structure shown in FIG. 8, the combination of the high refractive index material and the low refractive index material shown in FIG. 35, and the number of layers (pair) and an additional layer of the high refractive index material are added. As a result, a mask having a dielectric layer portion with a transmittance of 10% or less could be obtained. In this case, the energy density is 400 mJ / even with the mask from which the metal film layer is removed.
The threshold is 5 for the input of the excimer laser light of cm ^2.
A highly accurate ablation pattern of the resist film of 0 mJ / cm ² could be obtained.

FIG. 36 is a schematic process view for explaining an example of a method for manufacturing an exposure mask of an excimer laser exposure machine used for manufacturing a liquid crystal display device according to the present invention. In the figure, first, (a) a first dielectric layer having an optical path length having a film thickness of ¼ wavelength of the used ultraviolet light is formed on a quartz glass substrate 90 transparent to the ultraviolet light, and A dielectric multilayer film is formed on the first dielectric layer by forming a second dielectric layer having an optical path length of ¼ wavelength and smaller than the refractive index of the first dielectric layer. After that, a third dielectric layer having a refractive index larger than that of the glass substrate and having an optical path length that is ¼ wavelength of ultraviolet light used is formed on the uppermost layer of the dielectric multilayer film to form the dielectric multilayer. A film 91 is formed, and the dielectric multilayer film 9 is formed.
A metal film 92 is formed on top of 1.

(B) Photosensitive resist 93 on the metal film 92
Is applied, and is irradiated with ultraviolet rays 95 through an exposure mask 94, and is developed. (C) The metal film 92 is patterned by a photolithography process using the etching medium 96 with the resist 93 remaining after the development as a mask. (D) After patterning the metal film 92, the residual resist is removed to obtain a patterned layer of the metal film 92.

(E) The dielectric multilayer film 91 is etched by using the etching medium 97 with the opening pattern of the patterned metal film 92 as a mask. (F) Exposure for excimer laser processing including the multilayer dielectric film 91 and the metal film 92 superposed on the dielectric film 91 on the quartz glass substrate 90 by patterning the dielectric multilayer film 91 by the above etching to form an opening pattern. Get the mask.

The exposure mask according to the present invention, that is, the excimer laser processing mask is not limited to the above method. For example, an opening pattern of a photosensitive resist is formed on a metal film, and the opening pattern is used as a mask for excimer laser processing. It is also possible to obtain an exposure mask by irradiating a laser to remove the metal film and the underlying multilayer dielectric layer by ablation.

In this type of exposure apparatus, it is required to precisely align the exposure mask with the glass substrate which is the workpiece. An embodiment of the alignment mechanism of the exposure mask with respect to the glass substrate that is the workpiece will be described below. [Embodiment 9] FIG. 37 is a schematic view for explaining an embodiment of a mechanism for aligning an exposure mask with a glass substrate which is a workpiece. 1a is an excimer laser beam, 7 is an exposure mask,
7A is an alignment mark, 8 is an image forming optical system (image forming lens), 30 is a fluorescent plate, 30A is a fluorescent light emitting portion, 31 is a video camera, 32 is an arithmetic unit, 33 is an exposure mask adjusting mechanism, and 34 is focus / magnification. The adjusting mechanism, 35 is a back lighting lamp.

In the figure, an exposure mask 7, an image forming optical system 8, a fluorescent plate 30, and a video camera 31 are arranged on the optical path on which the excimer laser light 1a is irradiated. The excimer laser light 1a has a wavelength of, for example, 248n.
m, the energy density was adjusted to 10 to ²⁰ mJ / cm ² . The exposure mask 2 is, for example, a laminate in which 9 layers of HfO ₂ and SiO ₂ are alternately laminated at a film thickness of ¼ wavelength on a quartz substrate surface having a size of 330 mm × 250 mm and a thickness of 5 mm in the same manner as described above. It is a processed opening pattern.

The reflectance from the exposure mask 7 is 98% or more, and the S / N with the transmitted energy is 40 or more. A registration mark 7A is formed on the exposure mask 7. This alignment mark 7A is, for example,
It is formed in a cross pattern having a line width of 20 microns or less (preferably 5 microns). Alignment mark 7
It is needless to say that A is not limited to the cross pattern and may be another pattern such as a square shape.

FIG. 38 is a partial sectional view for explaining the structure of the fluorescent plate. The fluorescent plate 30 is a substrate that generates fluorescence upon irradiation with excimer laser light, and as shown in the figure, for example, has a size of 270 mm × 200 mm and a thickness of 1.1 mm.
Fluorescent paint film 30b is about 500n on quartz glass 30a.
A film formed with a film thickness of m is used. The alignment mark 7A of the exposure mask 7 by the irradiation of the excimer laser beam 1a is transferred to the fluorescent plate 30 via the 1: 1 imaging optical system 8.
An image is formed on the upper surface, and the fluorescent paint film 30b at the image forming portion emits fluorescent light.

When a material having a high absorption coefficient for the excimer laser light 1A is used as the material of the fluorescent plate 30 in this case, the above-mentioned fluorescent paint film is not necessarily required and the same effect can be obtained. The video camera 31 is fixed at a predetermined reference position, and captures the projected image (fluorescent image) 30A of the alignment mark 7A of the exposure mask 7 from the back surface of the fluorescent plate 30.

The image pickup data (image data) of the video camera 31 is input to the arithmetic unit 32. The arithmetic unit 32 calculates the position of the projected image 30A by comparison with the reference position to detect the amount of deviation of the projected image. The detected positional deviation data is given to the exposure mask adjusting mechanism 33, and the exposure mask adjusting mechanism 33 adjusts the position of the exposure mask 7 so that the positional deviation becomes zero.
That is, the position is adjusted so as to be a regular position.

The calculation of the positional deviation amount is performed by, for example,
The arithmetic unit 32 is provided with a memory for storing information relating to the position coordinates of the projection image 30A of the alignment mark, and the difference is calculated between the position coordinate data and the image data of the video camera. In this configuration example, the projected image 30A
Also, the focus state and size difference data are calculated by the arithmetic unit 32, and the result is given to the focus / magnification adjusting mechanism 34 to perform focus adjustment and magnification adjustment of the imaging lens 8. The reason why this focus and magnification need to be adjusted is
This is because it becomes important to adjust the wavelength used during ablation of the resist film by the excimer laser light and the focus position and magnification of the optical system.

On the other hand, a glass substrate (not shown) for a liquid crystal display element in the manufacturing process of the same size and shape as the fluorescent plate 30 is prepared, and this glass substrate is used.
It is compatible with and is set at exactly the same position. The glass substrate for a liquid crystal display element has, for example, a metal vapor deposition film formed on the entire surface of one surface thereof, and a resist film formed on the entire surface covering the metal vapor deposition film.

At the stage where the glass substrate for the liquid crystal display device is compatible with the fluorescent plate 30, the glass substrate is aligned in the correct position with respect to the exposure mask 7, and then pattern exposure is performed using the exposure mask 7. It Thereby, the resist film on the glass substrate for the liquid crystal display device,
Patterning is performed without performing a so-called conventional wet (wet) development process, and it is used as a mask for selective etching of a metal vapor deposition film disposed thereunder.

In the figure, a rear illumination lamp 35 for irradiating the glass substrate for the liquid crystal display element (or the fluorescent plate 30) with light from the rear surface thereof is arranged. When a material formed in the second layer is processed in the production of a glass substrate for a liquid crystal display element, an alignment mark is formed on the material, and the back illumination lamp 35 is used as a means for detecting the alignment mark. The alignment mark can be detected by the video camera 31 by irradiating light having the same wavelength as that of the fluorescent light of the projected image 30A.

According to this structure, when the fluorescent plate 30 compatible with the glass substrate for the liquid crystal display device projects the alignment mark 7A of the exposure mask 7 by the excimer laser light 1a during the manufacturing process, the projection position thereof. At, the alignment mark which is generated by fluorescence and is projected on the fluorescent plate 30 which is positioned corresponding to the glass substrate for the liquid crystal display element and which can be seen can fulfill the same function as the projection obtained by visible light. it can.

According to this embodiment, the alignment of the exposure mask 7 with respect to the glass substrate for the liquid crystal display element can be achieved with a simple structure. [Embodiment 10] FIG. 39 is a schematic view for explaining another embodiment of the alignment mechanism between the exposure mask and the glass substrate which is the workpiece, and 7B and 7C are alignment marks formed on the exposure mask 7. , 8a and 8b are image forming lenses dedicated to marks,
10B and 10C are alignment marks formed on the glass substrate 10 for a liquid crystal display element, 30B and 30C are fluorescent plates, and 3
Numerals 1B and 31C are video cameras that image the fluorescent light by projection of the alignment marks 7B and 7C formed on the fluorescent plates 30B and 30C, 31D and 31E are video cameras that image the alignment marks 10B and 10C of the glass substrate 10, and 36.
Is a position adjusting mechanism of the glass substrate 10, 40a and 40b are prisms, 40c and 40d are mirrors, and 41 is a glass substrate holder.

In this embodiment, the excimer laser beam 1a is composed of a plurality of prisms (two in the figure) 40a, 4a.
0b and mirrors 40 arranged corresponding to each prism
Irradiate the alignment marks 7B, 7C separated on the exposure mask 7 through the c, 40d. The alignment marks 7B and 7C are provided with fluorescence generating plates 30B and 30C provided on a glass substrate holder 41 that holds the glass substrate 10 for the liquid crystal display element in the manufacturing process through the image forming lenses 8a and 8b dedicated to the marks, respectively. An image is formed on the surface, and fluorescence is generated.

The fluorescent light generating plates 30B and 30C have the same structure as that of FIG. 38 described in the above embodiment, and the surface of the fluorescent paint film is formed to a thickness of about 500 nm. The light emission images from the fluorescent light generating plates 30B and 30C are detected by the mark detection video cameras 31B and 31C installed on the back surface thereof. On the other hand, on the part of the glass substrate 10 held by the glass substrate holder 41, the alignment mark 10
B and 10C are attached, and this alignment mark 10
B and 10C are detected by video cameras 31D and 31E arranged on the back surface of the glass substrate 10.

Then, the alignment marks 10B and 1B detected by the video cameras 31D and 31E, respectively.
From the positional relationship (separation distance) of 0C, the glass substrate holder 4
It is determined whether or not the position of the glass substrate 10 with respect to the glass substrate 1 is accurate. If the position is not accurate, the shift amount is calculated, and the position adjustment of the glass substrate 10 with respect to the glass substrate holder 41 is performed based on the calculated value. It is configured to be performed by the adjusting mechanism 36.

After such position adjustment is performed, the resist film formed on the glass substrate for the liquid crystal display element is patterned by the excimer laser beam 1a through the exposure mask 7 and the imaging lens 8. The above-described configuration also has a configuration for adjusting the focus and the magnification of the imaging lens as in the above-described embodiment.

The above-described aligning device for the exposure mask and the glass substrate is not limited to the patterning of the resist film, but can be similarly applied to the ablation processing machine for the lower layer TFT constituting thin film after this patterning. Next, an example of a debris removing device in processing a resist film and various thin films utilizing the ablation phenomenon of excimer laser light will be described.

In the patterning of a resist film utilizing the ablation phenomenon of excimer laser light and the processing of various thin films forming a TFT, debris is generated due to the ablation. Conventionally, the ablation process using this excimer laser light is applied to the field of micromachining, and debris, which is a processed product generated by ablation, cleans the work piece after processing, or depending on the processing material, It is reduced by processing in an inert atmosphere such as helium or in an oxygen atmosphere.

However, in such a conventional removal technique,
It is difficult to completely remove debris generated by ablation. In particular, it is difficult to remove debris that has re-adhered to the workpiece. Further, the debris forms are distributed in a wide range from a gaseous state to particles with a size of several μm, depending on the type of material and the intensity of incident energy, and debris that has been washed after processing has also occurred. Various methods must be considered depending on the form.

Also, in processing in a helium atmosphere, the debris was dispersed far away because the ejection speed of the ablation plume (explosion cloud) was faster than in air, and apparently the debris decreased. appear. This is considered to be a result of the generated debris being oxidized and turned into a gas in an oxygen atmosphere. The above-described processing in an atmosphere of helium or oxygen is effective only in processing relatively limited materials, and is not effective in processing all materials.

Furthermore, the essential point to be considered is that when the oscillation frequency of the excimer laser is increased in order to perform high-speed processing, the plume generated by the preceding excimer laser pulse is still in the optical path of the excimer laser. Since the ablation by the subsequent excimer laser is performed in the existing state, there is a problem that the excimer laser for the subsequent ablation causes energy loss.

For this reason, removing the plume generated by ablation at high speed has become a more important issue than simply removing debris. Hereinafter, embodiments of the ablation debris removing device according to the present invention will be described in detail. [Embodiment 11] FIG. 40 is a schematic view for explaining the constitution of one embodiment of an ablation debris removing device in the production of a liquid crystal display device according to the present invention, in which 50 is a suction nozzle,
Reference numeral 51 is an exhaust portion communicating with a vacuum pump (not shown), 52 is a suction buffer space, and 10 is a glass substrate which is a workpiece.

This embodiment has a structure having one suction nozzle 50, which is installed in a position close to the processing region of the workpiece 10 and at which the plume rising speed is sufficiently small, as shown by the arrow. As described above, the debris A is sucked. The shape of the opening of the suction nozzle may be cylindrical, elliptical, rectangular, slit-shaped, or the like depending on the material of the workpiece, the configuration of the excimer laser light processing apparatus, the energy used, and the like.

According to the present embodiment, it is possible to provide an excimer laser processing apparatus in which the debris does not adhere to the surface of the workpiece and the energy of the subsequent laser pulse is not reduced. In addition, the suction efficiency can be improved by installing a plurality of the above-mentioned structures around the processing area. [Embodiment 12] FIG. 41 is a schematic view for explaining the structure of another embodiment of the ablation debris removing device in the manufacture of the liquid crystal display device according to the present invention, and the same reference numerals as those in FIG. 40 correspond to the same functional portions.

In this embodiment, the suction nozzle 50 has a slit-like annular shape that is opened so as to surround and surround the processing region of the workpiece. It is desirable that the respective suction buffer spaces 3a be communicated with each other, and the exhaust unit 2 may be provided at one place. According to this embodiment, it is possible to provide an excimer laser processing apparatus in which the effect of removing debris is improved, the debris does not adhere to the surface of the workpiece, and the energy of the subsequent laser pulse is not reduced. [Embodiment 13] FIG. 42 is a schematic view for explaining the constitution of still another embodiment of the ablation debris removing device in the manufacture of the liquid crystal display device according to the present invention, and 53a, 53
3b is a side wall forming a suction container, 54 is an entrance window for excimer laser light, 55 is a bottom plate forming a suction container, and 55a.
Is an opening for laser light irradiation, and the same reference numerals as those in FIG. 40 correspond to the same functional portions.

The figure shows that debris suction can be performed more efficiently,
In addition, in order to completely remove the plume, the suction region has a suction container structure which substantially surrounds the suction region. That is, in this embodiment, the entrance window 5 for excimer laser light is used.
4 and the bottom plate 55 having an opening for irradiating the glass substrate 10 with laser light and the side walls 53a and 53b constitute a suction container. The suction buffer space 52 is in communication, and the exhaust unit 51 may be provided at one place.

It is desirable to make the opening 55a of the bottom plate 55 as small as possible, but it is necessary to prevent the movement of the shockwave front during ablation so as not to interfere with the opening 55a. Is preferred. The side walls 53a and 53b are also shaped so as not to hinder the irradiation of the laser beam. Also,
It is important that the entrance window 54 is made of a material that transmits excimer laser light, for example, a quartz plate, and its installation height is set higher than the reach distance of the shockwave front.

Further, the bottom plate 55 is brought as close as possible to the glass substrate 10 to be ablated,
In addition, by increasing the entire area, the efficiency of suction can be further improved. It is considered that this is because the pressure in the suction container becomes low and the speed of the shockwave front increases. However, in the suction, it is necessary to consider a flow velocity and a streamline that do not cause local fluctuation of the refractive index due to gas disturbance in the optical path of the excimer laser light. [Embodiment 14] FIG. 43 is a schematic view for explaining the constitution of still another embodiment of the ablation debris removing device in the manufacture of the liquid crystal display device according to the present invention, which is more specific for being attached to the ablation processing device. The suction buffer space 52 communicates with the exhaust part 51, and 56 is a suction container. Note that the same reference numerals as those in FIG. 42 correspond to the same functional portions.

In the figure, the height of the suction container 56 is 65.
mm, and the bottom plate 55 of the suction container is placed on the surface of the workpiece with a gap of 1 mm. The excimer laser light enters through the entrance window 54 and irradiates the glass substrate through the opening 55a of the bottom plate 55. The debris A generated by ablation reaches the exhaust unit 51 from the suction buffer space 52 through the suction nozzle 50 as shown by the arrow, and is exhausted by a vacuum pump (not shown).

As a result of performing ablation processing of the novolac resin with the ablation processing device using the ablation debris removing device of this configuration, the laser oscillation frequency of 2 kHz is about 1.5 times as high as that without the suction container. Was able to obtain the ablation rate of. Furthermore, debris could be completely removed except for a small portion at the edge of the laser irradiation part.

With this configuration, it can be easily installed in the processing portion of the ablation processing device,
High quality processing can be performed by removing the generated debris. FIG. 44 is an explanatory diagram of a configuration example in which the ablation debris removing device shown in FIG. 43 is attached to an ablation processing machine and is applied to processing of a color filter substrate that constitutes a liquid crystal display element.
a is an excimer laser beam, 1a 'is an irradiation laser beam, 7
Denotes an exposure mask (dielectric mask), 10 ′ denotes a color filter substrate which is a workpiece, and 11 denotes a color filter substrate.
0'X-Y table, 60 is color filter layer, 60
a is an unnecessary convex portion formed on the color filter layer, 61 is a uniform illumination optical system, 62 is an imaging optical system (lens), 63
Is a debris removal device.

In the figure, an excimer laser 1 oscillates a laser beam 1a having a wavelength of 248 nm, and a uniforming illumination optical system 61 including an integrator causes a convex portion 6 on the surface of the color filter layer 60 of the color filter substrate 10 '.
Illumination of a 2 × 50 mm ² slit-shaped mask pattern is performed on the exposure mask 7 having an opening formed to cover the removal region 0a.

This mask pattern is imaged on the surface of the color filter layer 60 by a 1: 1 imaging lens 62. The working distance of the imaging lens 62 is 70 mm, during which the ablation debris removing device 131 m incorporated in a suction container having a height of 65 mm as shown in cross section in FIG.
m. For debris suction, a dry vacuum pump or a vacuum suction device having an evacuation capacity of 300 liters / second is used. The incident energy density of the excimer laser light is 300 mJ / cm ² .

By the ablation processing apparatus having the above-described structure, unnecessary convex portions 7a formed on the color filter layer of the color filter substrate are removed and flattened, and debris generated by the processing remains on the color filter layer. It was possible to obtain a high quality color filter substrate. FIG. 45 is a developed perspective view illustrating a structural example of a TFT type liquid crystal display device manufactured according to the present invention.

In the figure, MDL is a liquid crystal display device, S
HD is an upper frame metal shield case, WD
Is a display window for defining an effective screen of the liquid crystal display device, PNL is a liquid crystal display element, SCP is a diffusion plate, PCB1 is a drain side circuit board, PCB2 is a gate side circuit board, PCB3 is an interface circuit board, PRS is a prism sheet, S
PS is a diffusion sheet, GLB is a light guide, RFS is a reflection sheet, BL is a backlight, LP is a cold cathode fluorescent lamp constituting a lamp of the backlight BL, LS is a reflection sheet, and GC
Is a rubber bush, LPC is a lamp cable, MCA is a lower case having an opening MO for installing the light guide GLB, J
N1,2,3 are joiners for connecting circuit boards, TCP
1, 2 are tape carrier packages, INS 1, 2, 3
Is an insulating sheet, GC is a rubber cushion, BAT is a double-sided adhesive tape, and ILS is a light shielding spacer.

Each of the above components is laminated between the metal shield case SHD and the lower case MCA and is sandwiched and fixed to form the liquid crystal display device MDL. Liquid crystal display element P
A diffusion plate SCP is laminated on the NL, and various circuit boards are attached around the diffusion plate SCP to drive the image display.
Further, on the back surface of the liquid crystal display element PNL, a backlight BL formed by laminating various optical sheets on the light guide GLB is installed, and an image formed on the liquid crystal display element PNL is illuminated and displayed on the display window WD. .

The TFT-type liquid crystal display device assembled by using the present invention described above is capable of forming a thin film pattern with high accuracy and having a significantly shortened process step, and various display devices having high image quality display performance. Applicable to The processing method using the ablation phenomenon of the excimer laser light according to the present invention is applied to the resist film of the liquid crystal display element or the TF.
The present invention is not limited to the patterning of various thin films forming the T substrate or the color filter substrate, but can be applied to the patterning of various thin films accompanied by similar patterning.

[0227]

As described above, according to the present invention,
A resist film is formed from a high ablation rate and low debris polymer material, and the resist film is developed and the remaining resist film is removed by lithography using the ablation phenomenon of excimer laser light. Since patterning can be realized without using a wet process, the influence on the environment can be eliminated by waste liquid of the developer, the release agent, and other processing agents. Further, the process of forming the thin film pattern itself is simplified, and the process time can be greatly reduced, thereby reducing the manufacturing cost of the liquid crystal element.

Further, the optical system is prevented from being damaged by the high-energy excimer laser light, and various thin films can be patterned on a large-area glass substrate with high accuracy, and the mass production effect is great. Further, the exposure mask according to the present invention has high durability against high-energy excimer laser light, and avoids deviation of the boundary of the pattern with respect to a large-area glass substrate in the step-scan method, and thus a highly accurate patterning process can be performed. It is possible.

Since the exposure mask and the glass substrate as the object to be processed can be aligned with high precision with a simple structure and debris generated by ablation can be removed in real time, high-speed processing and a clean processing environment are possible. It is possible to realize high quality of the manufactured liquid crystal display device.

[Brief description of drawings]

FIG. 1 is a process diagram illustrating a method for manufacturing a liquid crystal display element according to the present invention using a resist material for ablation processing of excimer laser light.

FIG. 2 is a process diagram illustrating a method for manufacturing a liquid crystal display device according to the present invention using a resist material for ablation processing of excimer laser light.

FIG. 3 is a schematic diagram for explaining an example of the configuration of an exposing machine utilizing an ablation phenomenon of an excimer laser used for manufacturing a liquid crystal display device according to the present invention.

FIG. 4 is a schematic sectional view illustrating an example of a basic configuration of a dielectric multilayer film mask.

FIG. 5 is a schematic cross-sectional view illustrating another example of the basic configuration of the dielectric multilayer film mask.

6 is an explanatory view as a parameter the number of layers the relation of the refractive index ratio corresponding to FIG. 4 and n _e / n ₁ and reflectance.

7 is an explanatory view as a parameter the number of layers the relation of the refractive index ratio corresponding to FIG. 5 and n _e / n ₁ and reflectance.

FIG. 8 is a schematic cross-sectional view illustrating a basic structure of an excimer laser processing mask (exposure mask) constituted by a dielectric multilayer film mask according to the present invention.

FIG. 9 shows the refractive index ratio n of the multilayer dielectric layer when Al ₂ O ₃ is used as an additional high refractive index layer except for the metal film layer of FIG.
FIG. 4 is a characteristic explanatory diagram of the relationship between ₂ / n ₃ and reflectance.

FIG. 10 is an explanatory view of an ablation phenomenon schematically showing a shadow graph of an ablation phenomenon by a dye laser (pulse width: about 5 ns) which is delay-synchronized with a pulse of an excimer laser beam.

FIG. 11 is a plan view illustrating a configuration near one pixel of an active matrix type color liquid crystal display device to which the present invention is applied.

FIG. 12 is a cross-sectional view of a main part, taken along line 3-3 in FIG. 11;

FIG. 13 is an explanatory diagram of a forming process by patterning a thin-film multilayer structure constituting a TFT on a lower transparent glass substrate.

FIG. 14 is an explanatory diagram of a forming process by patterning a thin film multilayer structure constituting a TFT on a lower transparent glass substrate.

FIG. 15 is an explanatory diagram of a forming step by patterning a thin-film multilayer structure constituting a TFT on a lower transparent glass substrate.

FIG. 16 is a schematic diagram illustrating an outline of an optical system of an exposure / development apparatus used in a method of manufacturing a liquid crystal display device according to the present invention.

FIG. 17 is an explanatory view of a principle of dividing a substrate pattern for an exposure mask for step-scan in a method for manufacturing a liquid crystal display element of the present invention.

FIG. 18 is a plan view schematically illustrating a configuration example of an exposure mask used in the method for manufacturing a liquid crystal display element according to the present invention.

FIG. 19 is a principle diagram illustrating division of excimer laser light by a lens array in an ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention.

FIG. 20 is an explanatory diagram of an illumination optical system of an ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention.

FIG. 21 is an explanatory diagram of uniforming illumination light of an exposure mask of an ablation developing machine used in a method of manufacturing a liquid crystal display element of the present invention.

FIG. 22 is a schematic diagram illustrating a scanning method of an ablation developing machine used in the method for manufacturing a liquid crystal display device of the present invention.

FIG. 23 is an explanatory diagram of an example of setting the position of an illumination area in scanning by an ablation developing machine used in the method for manufacturing a liquid crystal display element of the present invention.

FIG. 24 is a diagram illustrating an overall configuration of an ablation developing apparatus in which excimer laser light source units and a developing optical system of an ablation developing machine used in a method of manufacturing a liquid crystal display device of the present invention are separated from each other by separate walls and installed in rooms having different cleanliness. FIG.

FIG. 25 is an explanatory diagram of a shift correction method for tilting a transmission window plate through which a laser light beam passes in an ablation developing machine used in a method of manufacturing a liquid crystal display element of the present invention to translate an optical axis in parallel.

FIG. 26 is a schematic diagram of a configuration of an exposure optical system of an ablation developing machine for explaining a seventh embodiment of the present invention.

FIG. 27 is a schematic diagram illustrating an example of an arrangement of cylindrical lenses used for dividing a light source in an X direction and a Y direction in a seventh embodiment of the present invention.

FIG. 28 shows a black matrix (BM) formed on a color filter side glass substrate of a liquid crystal display device as an example of an opening pattern of an exposure mask in a seventh embodiment of the present invention.
It is explanatory drawing of the example of a pattern and the arrangement | positioning relationship of the blade for slit illumination.

FIG. 29 is a schematic diagram of patterning by ablation development of a color filter for explaining an eighth embodiment of the present invention.

FIG. 30 is an explanatory view of a preferable division line of an exposure mask of an ablation exposure machine used in a method of manufacturing a liquid crystal display device according to the present invention.

FIG. 31 is an explanatory diagram of a dividing line to be avoided.

FIG. 32 is a schematic view for explaining an example of division of a substrate for explaining an embodiment of a method for forming a resist pattern in a method for manufacturing a liquid crystal display element according to the present invention.

FIG. 33 is a plan view illustrating a specific example of an exposure mask used in the present example.

FIG. 34 is an explanatory diagram of an irradiation state of excimer laser light on a resist on a substrate via an exposure mask.

FIG. 35 shows a combination of a high-refractive-index layer material and a low-refractive-index layer material, which are materials for an exposure mask of an excimer laser exposure machine used for manufacturing a liquid crystal display device according to the present invention, and a minimum number of layers having a transmittance of 10% or less. FIG.

FIG. 36 is a schematic process chart illustrating an example of a method for manufacturing an exposure mask of an excimer laser exposure machine used for manufacturing a liquid crystal display device according to the present invention.

FIG. 37 is a schematic diagram illustrating an embodiment of a positioning mechanism for aligning an exposure mask with a glass substrate as a workpiece.

FIG. 38 is a partial cross-sectional view illustrating a configuration of a fluorescent plate.

FIG. 39 is a schematic view illustrating another embodiment of the alignment mechanism between the exposure mask and the glass substrate that is the workpiece.

FIG. 40 is a schematic diagram illustrating the configuration of an embodiment of an ablation debris removing apparatus in the manufacture of a liquid crystal display device according to the present invention.

FIG. 41 is a schematic view illustrating the configuration of another embodiment of the ablation debris removing apparatus in the manufacture of a liquid crystal display device according to the present invention.

FIG. 42 is a schematic view illustrating the configuration of still another embodiment of the ablation debris removing apparatus in the manufacture of a liquid crystal display device according to the present invention.

FIG. 43 is a schematic diagram illustrating the configuration of still another embodiment of the ablation debris removing apparatus in the manufacture of a liquid crystal display device according to the present invention.

44 is an explanatory diagram of a configuration example in which the ablation debris removal device shown in FIG. 43 is mounted on an ablation processing machine and applied to processing of a color filter substrate forming a liquid crystal display element.

FIG. 45 is an exploded perspective view illustrating a structural example of a TFT type liquid crystal display device manufactured according to the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 excimer laser 3, 5 lens 4 split lens 6 condenser lens 7 exposure mask 8 imaging lens 9 entrance pupil 10 resist coated glass substrate as workpiece 11 XY table (11a is XY mask table, 11b is X -Y substrate table).

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location H01L 29/786 H01L 29/78 627C 21/336 (72) Inventor Nobuaki Hayashi 3300 Hayano, Mobara-shi, Chiba Co., Ltd. Hitachi Electronic Devices Division (72) Inventor Yoshifumi Tomita 3300 Hayano, Mobara-shi, Chiba Hitachi Electronic Devices Division

Claims (6)

[Claims] 1. A glass substrate on which a metal film, a dielectric insulating film, a thin film of a semiconductor film, or a multilayer film in which a part of the thin film is formed in a pattern is formed for forming a liquid crystal display element. Apply a resist film composed of a molecular material, and irradiate an excimer laser through a mask having a predetermined opening pattern to remove the resist film in the irradiated portion by an ablation phenomenon, thereby corresponding to the opening pattern of the mask. A resist film pattern is formed by exposing a thin film, and the thin film exposed by the resist film pattern is removed by etching, and then a residual resist film is removed by irradiation with an excimer laser by an ablation phenomenon. Method for manufacturing liquid crystal display device. 2. A method for manufacturing a liquid crystal display device according to claim 1, wherein the extinction coefficient of the resist film is 5 × 10 ⁴ cm ⁻¹ or more for excimer laser light having a wavelength of 248 nm or 308 nm. . 3. The method according to claim 1, wherein the polymer compound is
A method for manufacturing a liquid crystal display element, which is a thermosetting type in which a cyclic or network-like crosslinked structure is formed by either heating or drying. 4. The method of claim 1, wherein the resist film is, for the wavelength 248 nm, the energy density of 100 mJ / cm ² of excimer laser light pulse, 0.04 .mu.m / s
A method for manufacturing a liquid crystal display device, wherein the method has an ablation speed not less than hot. 5. A metal film, a dielectric insulating film, a thin film of a semiconductor film,
Or one glass substrate obtained by processing a multilayer film composed of one or more of the above thin films by an ablation phenomenon of an excimer laser using a resist film made of a polymer material, a black matrix and a plurality of color filters are formed. A liquid crystal display device in which a liquid crystal layer is sandwiched between the other glass substrates. 6. The black matrix and / or the plurality of color filters of the glass substrate according to claim 5, wherein the black matrix film and / or the plurality of color filter films are formed by an excimer laser through a mask having a predetermined opening pattern. A liquid crystal display device, characterized in that the black matrix film and / or a plurality of color filter films in the irradiated part are processed by an ablation phenomenon by irradiation.