JP2006313284A - Method for producing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a color filter which is easily applied to a large substrate and hardly causes unevenness. <P>SOLUTION: The method for producing a color filter comprises: an exposure step of exposing a total pattern to a photosensitive film; a developing step of forming a patterned film 30b by developing the total pattern-exposed photosensitive film; and a washing step of washing the patterned film 30b. In the exposure step, a light dot of a predetermined size is projected on the photosensitive film such that the light dot is repeatedly projected on the photosensitive film while being dislocated by a distance smaller than the diameter of the light dot, whereby the total pattern is exposed. In the washing step, liquid droplets 204 are obliquely jetted on the patterned film 30b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color filter.

  The photolithography method is mainly employed in applications where it is required to form a precise pattern of several μm to 100 μm, such as a flat display such as a liquid crystal display and a plasma display, and manufacture of an electronic circuit.

  The photolithography method is a process including application of a photosensitive film (resist) to a substrate, exposure to irradiate the photosensitive film with a light pattern, patterning of the photosensitive film by development of the photosensitive film (formation of a resist pattern), and the like. The photolithography method can cope with a large-sized substrate because the overlay accuracy of the optical pattern can be increased.

  By the way, when manufacturing a color filter for a flat display, it is necessary to apply a photolithography method to a particularly large glass substrate, for example, a glass substrate having a width exceeding 2 m. For this reason, with the increase in the size of such a substrate, in the manufacture of a color filter, further improvement in exposure accuracy and cost reduction are required for the photolithography method.

  Conventionally, a mask projection method using a highly transparent quartz mask has been the mainstream as an exposure method of an optical pattern in a photolithography method used for manufacturing a color filter. However, the quartz mask itself is expensive, and it is not preferable because it is necessary to prepare a mask for each optical pattern.

In recent years, a method of directly writing a light pattern on a photosensitive film by scanning a laser spot light with a polygon mirror or the like based on light pattern data that is the basis of a light pattern without using an expensive photomask, so-called direct exposure (direct exposure) A drawing method has been proposed (see, for example, Patent Documents 1 and 2). There is also a maskless projection method in which a combination of light dots of a predetermined size is projected onto a photosensitive film using a spatial light modulator or the like to form a light pattern.
JP 09-073171 JP 09-318809 A

  Since the direct exposure method does not use an expensive photomask, it can be expected not only that the manufacturing cost can be reduced, but also many advantages such as shortening the line switching time and new product development time.

  However, in the direct exposure method, the photosensitive film is irradiated with a light pattern by scanning spot light using a polygon mirror or the like, and therefore the angle at which light is incident on the photosensitive film varies greatly depending on the location of the photosensitive film. Therefore, the cross-sectional shape of the pattern of the photosensitive film after development becomes extremely non-uniform depending on the location.

  For a large substrate such as a color filter, it is necessary to form a large overall pattern on the photosensitive film, and it takes a lot of time to form a large overall pattern with a single polygon mirror. Therefore, in order to shorten the throughput, a partial pattern is generated by dividing the entire pattern into a plurality of parts, and the partial patterns are drawn on the photosensitive film at a plurality of locations simultaneously using a large number of polygon mirrors or the like. Is required. As a result, due to non-uniformity in the cross section of the pattern at the boundary between the drawing areas of each partial pattern, a slight shift occurs in the seam, resulting in unevenness that is a problem when used as a color filter.

  On the other hand, in the maskless projection method, since a pattern is formed by combining light dots of a predetermined size, the resolution of the pattern is restricted by the size of the light dots. Therefore, the curve and the oblique line are not smooth, and a periodic pattern is often used in the color filter, but moire tends to occur in the case of such a periodic pattern.

  The present invention has been made in view of such problems, and is easy to apply to a large substrate, is less likely to cause moire and unevenness, and can produce a color filter that can form a patterned film with sufficient resolution. It aims to provide a method.

  As a result of intensive studies by the present inventors, a light dot having a predetermined size is projected onto the photosensitive film while overlapping the exposure position while shifting the exposure position by a distance smaller than the diameter of the light dot, thereby forming an overall pattern and then developing. By doing so, it is possible to form a film patterned with little moire and unevenness and with high resolution, and further, moire and unevenness can be further reduced by washing the patterned film after development by jetting droplets obliquely. As a result, the present invention has been completed.

  The color filter manufacturing method according to the present invention includes an exposure step of exposing the entire pattern to the photosensitive film, a developing step of developing the photosensitive film exposed to the entire pattern to form a patterned film, and a patterning process. And a cleaning process for cleaning the film. In the exposure step, a light dot having a predetermined size is projected onto the photosensitive film, and the light dot is projected on the photosensitive film while being shifted by a distance smaller than the diameter of the light dot. Expose the pattern. In the cleaning step, droplets are ejected obliquely with respect to the patterned film.

  According to the present invention, since the entire pattern is formed by projecting the light dots while being shifted by a distance smaller than the diameter of the light dots, the outline of the pattern can be drawn with a resolution lower than that of the light dots. . Therefore, the diagonal lines and curves in the entire pattern can be made smooth, and the occurrence of the moire phenomenon in the periodic pattern can be suppressed.

  Further, since the entire pattern is exposed by projecting the light dots while being shifted, it is easy to apply to a large substrate. Also, instead of scanning the beam with a polygon mirror or the like, the light dots are overlapped while shifting their projection positions, so the incident angle of the light incident on the photosensitive film is compared to the beam scanning with a polygon mirror, etc. Difficult to vary within partial patterns. Therefore, the cross-sectional shape of the pattern of the photosensitive film after development is almost uniform, and unevenness at the boundary of the light dots is less likely to occur.

  In addition, since the patterned film is cleaned by spraying droplets obliquely to the patterned film after development, residues (protrusions, etc.) that inevitably occur in the patterned film are effectively removed. Then, the edge shape of the pattern is averaged, and moire and unevenness can be reduced more efficiently.

  Here, in the exposure step, using a spatial light modulator in which a plurality of light modulation elements that can select a state of projecting light dots on the photosensitive film or a state of not projecting light dots on the photosensitive film are arranged, A partial pattern formed by the presence or absence of a light dot corresponding to the state of each light modulation element is exposed to the photosensitive film, and this partial pattern is superimposed on the photosensitive film while being shifted by a distance smaller than the diameter of the light dot. It is preferable to expose the entire pattern by exposing.

  According to this, the whole pattern can be suitably exposed on the photosensitive film by overlapping the partial patterns and exposing them a plurality of times. Further, since the exposure of the single gradation pattern is performed using the spatial light modulator, the illuminance management is easier and the application to a large substrate is easier.

  Further, when performing exposure while shifting using a spatial light modulator in which a plurality of such light modulation elements are arranged, unevenness and moire due to the width of the spatial light modulator may occur. In this case, since unnecessary residues are efficiently removed by ejecting the droplets obliquely, the effect of reducing such unevenness and moire is great.

  As the light modulation element, the first state in which light from the light source is reflected or transmitted to the photosensitive film or the light from the light source is not reflected or transmitted to the photosensitive film according to the brightness of each part of the partial pattern. What selects any state of a 2nd state can be utilized suitably.

  A specific example of the color filter is a color filter for a flat display.

  In addition, by such a manufacturing method, for example, a black matrix, a transparent colored resin layer, an alignment regulation structure, a scattering layer, a microlens, a spacer, and the like in a color filter can be formed.

  Specific examples of the photosensitive film include a light-shielding resin layer, a colorless transparent resin layer, and a transparent colored resin layer.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the color filter which can form the film | membrane patterned with sufficient resolution which is easy to apply to a big board | substrate, does not produce a moire and nonuniformity, and sufficient resolution is provided.

  A method for manufacturing a color filter according to the present embodiment will be described.

  Here, in order to pattern the black matrix of the color filter, a patterning method in which the entire pattern 12 is exposed to the light-shielding photosensitive film 30a, developed, and washed will be described in detail.

  First, in this embodiment, the entire pattern is exposed on the photosensitive film 30a by using an exposure apparatus 1 as described below. The exposure apparatus 1 is an apparatus that irradiates the entire pattern 12 of light onto the substrate 30. At least a stage 40 that supports the substrate 30, a stage drive unit 45 that drives the stage 40, a light source 50, and a partial pattern of light. 17 includes a spatial light modulator 60 and a computer device 70.

  The stage 40 places the substrate 30 on the upper surface thereof. The stage driving unit 45 can expose the partial pattern 17 of light emitted from the spatial light modulator 60 to a desired position on the substrate 30 by driving the stage 40. At least a photosensitive film 30 a is provided on the upper surface of the substrate 30. The stage driving unit 45 can move the photosensitive film 30 a on the stage 40 in the main scanning direction X and the sub-scanning direction Y with respect to the spatial light modulator 60.

  The light source 50 is a light source that irradiates light to the spatial light modulator 60. The frequency of light from the light source is not particularly limited as long as the photoreaction can proceed in the photosensitive film 30a, but it is preferable to use a wavelength of about 200 to 450 nm. Examples of the light source that emits light having such a wavelength include high-pressure mercury lamps, xenon lamps, various lasers such as semiconductors and YAG, and higher-order gradation waves thereof. The light source 50 irradiates all the light modulation elements 62 (described later) provided in the spatial light modulator 60 with light.

  The spatial light modulator 60 has a plurality of light modulation elements 62 arranged in a matrix on the surface thereof, and is provided above the stage 40 so as to face the substrate 30. Each light modulation element 62 is controlled by an exposure control unit 76 of a computer device 70 to be described later, and is in a first state (see B1 in FIG. 1) in which light from the light source 50 is projected onto the photosensitive film 30a, or a light source. The light from 50 is guided to a part other than the photosensitive film 30a, that is, it is set to one of the second states (see B2 in FIG. 1) where the light is not projected onto the photosensitive film 30a.

  Light dots, that is, light dots, are projected onto the photosensitive film 30a by the light modulation element 62 in the first state, and the light is not irradiated on the photosensitive film 30a by the light modulation element 62 in the second state. Dots are formed. Accordingly, a two-dimensional partial pattern 17 of light in which light dots or dark dots are combined in a matrix is projected on the photosensitive film 30a according to the state of each light modulation element 62.

  Specifically, the spatial light modulator 60 includes a DMD (Digital Micromirror Device) that switches between the first state and the second state by changing the inclination of the reflection surface of the minute mirror (light modulation element 62), reflection. LCOS (Liquid Crystal On Silicon) that realizes the first state and the second state by switching between reflection / non-reflection using a liquid crystal display element (light modulation element 62) of the type, and one light dot comprising a plurality of ribbons GLV (Grating Light Valve) elements that realize a first state and a second state by switching a number of ribbon groups (light modulation elements 62) corresponding to (pixels) and switching diffraction / non-diffraction by each ribbon group, etc. A transmissive spatial light modulator that realizes the first state and the second state by switching between transmissive and non-transmissive using a reflective spatial light modulator or a transmissive liquid crystal display element (light modulating element 62) Use Can. When a transmissive spatial light modulator is used, the light source 50 is disposed on the opposite side of the substrate 30 with the spatial light modulator 60 interposed therebetween. In the spatial light modulator 60, the light modulation elements 62 may be arranged in 1 row m columns, n rows 1 column, or n rows m columns, where n and m are integers of 2 or more, respectively. .

  The computer device 70 is connected to the spatial light modulator 60, the light source 50, and the stage drive unit 45, and controls them. The computer device 70 executes at least the functions of the overall pattern data storage unit 72, the partial pattern data generation unit 74, and the exposure control unit 76 when the CPU executes the program.

  The overall pattern data storage unit 72 stores the overall pattern data 10 corresponding to the overall pattern 12 to be exposed on the photosensitive film 30a of the substrate 30 (see FIG. 2). This whole pattern data 10 is data including light and dark two-tone light / dark information of each part in the whole pattern 12, and is inputted from the outside by a known method prior to exposure. Here, the overall pattern data 10 and the overall pattern 12 are arbitrary, but, for example, as shown in FIG. 2, they have rectangular contour patterns 10a and 10b, rhombus contour pattern 10c, curved contour pattern 10e, thin line pattern 10e, and the like. It can be a pattern and has two gradations of light or dark as a whole. In the drawings of this specification, a dark portion in each pattern indicates a bright portion.

  Returning to FIG. 1, the partial pattern data generation unit 74 generates a plurality of partial pattern data 15 based on the overall pattern data 10 stored in the overall pattern data storage unit 72. The partial pattern data 15 is, for example, as shown in FIG. Each partial pattern data 15 is a matrix pattern composed of a plurality of pixels corresponding to the arrangement of the light modulation elements 62 in the spatial light modulator 60. Each pixel is formed by a pixel 15on where a light dot is to be projected or a pixel 15off where a light dot is not to be projected. In the present embodiment, the light dots formed by the spatial light modulator 60 are generally square, and the pixels are also square. The partial pattern data 15 will be described later.

  Returning to FIG. 1, the exposure control unit 76 supplies the plurality of partial pattern data 15 generated by the partial pattern data generation unit 74 to the spatial light modulator 60 to drive each light modulation element 62 and to turn on the light source 50. Driven, the partial pattern 17 corresponding to each partial pattern data 15 is exposed on the photosensitive film 30a.

  Further, the exposure controller 76 drives the stage 40 in the main scanning direction (X) and the sub-scanning direction (Y), and as shown in FIG. 4, the partial patterns 17 are sequentially overlapped so that they partially overlap each other. The entire pattern 12 is exposed by overlapping the partial patterns 17. Here, the partial pattern 17 is a partial pattern corresponding to the partial pattern data 15, and each pixel is a light dot 17on corresponding to the pixel 15on on which the light dot is to be projected, or a pixel on which the light dot is not to be projected. It is formed by dark dots 17off corresponding to 15off.

  In this embodiment in particular, as shown in FIG. 4, the partial pattern 17 is exposed in an overlapped manner in order in a certain direction while being shifted by a distance H smaller than the diameter W of the light dot 17 on in this direction. A pattern band 12b is obtained. In this case, the diameter W of the light dot 17on is the width in the shifting direction of the light dot 17on. Therefore, when the partial pattern 17 is exposed while being shifted in the oblique direction in the dot arrangement, the width W along the oblique direction of the light dot 17on is obtained, and the partial pattern is not in the oblique direction but in the row or dot arrangement of the partial pattern 17 When the exposure is performed while shifting in the column direction, the width of the light dot 17on is along the direction. When the light dot is circular, the diameter of the light dot 17on is the diameter.

  In the present embodiment, as shown in FIG. 4 in particular, the entire pattern band 12b is obtained by overlapping a large number of partial patterns 17 while shifting the partial pattern 17 by a distance H shorter than the width W in an oblique direction.

  In FIG. 4, as an example, the partial pattern 17 corresponding to the partial pattern data 15 shown in FIG. As will be understood from FIG. 4, when the shifting distance H is smaller than the diameter W of the light dots, the light dots 17on partially overlap each other, and the resolution is smaller than the size of the light dots 17on of the entire pattern 12, that is, the pixels. Thus, it is possible to draw the outline of the entire pattern band 12b and the entire pattern 12.

  Note that the illuminance of one light dot 17on in the partial pattern 17 is such that when the photosensitive film is a negative type insolubilized by light, the light dot 17on is irradiated many times, for example, several tens to several hundreds times. In the case of a positive type in which the photosensitive film is solubilized by light so that it can remain without being removed at any later development step, one light dot 17on is irradiated multiple times. Thus, it is set so as to be solubilized that the portion can be completely removed in the subsequent development step. Therefore, the portion where the light dot 17on is superimposed many times corresponds to the black portion in the entire pattern data 10 of FIG. 2 and is developed. On the other hand, the portion where the light dot 17on is not irradiated or the portion where the light dot 17on is hardly irradiated corresponds to the white portion in the entire pattern data 10 of FIG. 2, and is not developed. In practice, since the overall pattern is formed by superimposing many times at each place with a finer pitch H than in FIG. 4, the formed pattern has extremely high resolution and is substantially This is a two-tone pattern.

  In the present embodiment, as shown in FIG. 5, the entire pattern band 12b is exposed by overlapping the partial patterns 17 while being shifted in an oblique direction, and a plurality of the entire pattern bands 12b are arranged in parallel with each other and exposed. The entire pattern 12 is formed on almost the entire photosensitive film 30a. At this time, the end portions in the width direction of the entire pattern band 12b overlap each other.

  And in the partial pattern data generation part 74 mentioned above, the whole pattern 12 formed by superimposing each partial pattern on the premise that each partial pattern 17 is exposed in this way, the whole pattern data storage part 72 is set so as to correspond to the entire pattern data 10 stored in 72.

  As a result, the entire pattern 12 corresponding to the entire pattern data 10 is exposed on the photosensitive film 30a to form a latent image.

  In FIG. 4, the same partial patterns 17 are overlapped for simplicity of explanation, but in general, different partial patterns 17 are overlapped with each other, for example, corresponding to FIG. 2. An arbitrary whole pattern can be reproduced.

  Next, when the exposed photosensitive film 30a is developed with a known developer, a patterned film 30b (see FIG. 4) is completed.

  Specifically, when the negative photosensitive resin is exposed, the irradiated portion, for example, the hatched hatched portion in FIG. 4 remains, and when the positive photosensitive resin is exposed, the irradiated portion is removed. Is done.

  Thereby, for example, as shown in FIG. 6, an opening 30d is formed in the patterned film 30b.

  Thereafter, the patterned film 30b on the substrate 30 is washed. Here, as shown in FIG. 6, by supplying the liquid from the liquid supply source 202 to the nozzle 201, the droplets 204 are ejected from the nozzle 201, and these droplets 204 are applied to the patterned film 30b. Thus, the residue remaining on the patterning film 30b, for example, the protruding portion 30z remaining on the edge of the opening is removed.

  Specifically, for example, water, a developer used in the development process, a solution obtained by diluting it, or the like can be used as the liquid forming the droplets 204. It is also effective to add a surfactant to these.

  The droplet 204 is preferably discharged from the nozzle 201 at a pressure of 1 to 25 MPa, and more preferably discharged at a pressure of 2 to 15 MPa. If the pressure is higher than 25 MPa, the possibility that the pattern is broken increases. If the pressure is lower than 1 MPa, the residue removal efficiency tends to decrease. A suitable droplet diameter is 10 to 50 μm.

  Further, the nozzle 201 is disposed obliquely so that the droplet 204 strikes the patterned film 30b obliquely. Specifically, as shown in FIG. 5, if the angle formed by the axis of the nozzle 201 and the line L perpendicular to the patterned film 30b is θ, θ ≠ 90 °, particularly 5 ° ≦ θ ≦. The angle is preferably 45 °. When θ is less than 5 °, the landed droplet 204 forms a liquid layer having a relatively large thickness, and the mechanical energy of the landed droplet 204 is reduced thereafter, so that the residue removal efficiency is lowered. Tend. On the other hand, when θ exceeds 45 °, the flight distance of the droplet 204 tends to be long, which is not preferable because the energy of the droplet 204 is attenuated by friction between the droplet and air.

  Specifically, as shown in FIG. 6, it is preferable to apply the droplet 204 to the patterned film 30 b from the fixed nozzle 201 while moving the substrate 30. At this time, as shown in FIG. 5, the nozzle is preferably inclined so that the droplet 204 is directed in the direction opposite to the traveling direction of the substrate 30, but the nozzle is inclined so as to be directed in the traveling direction. However, it can be implemented.

  Thereafter, an air flow is blown onto the surface of the substrate 30 from the air knife connected to the air source 210 against the patterned film 30b after cleaning, and the substrate 30 is dried. In this way, a black matrix as a patterned film is completed.

  Then, the effect | action by this embodiment is demonstrated.

  According to the present embodiment, the partial pattern 17 is shifted by a distance H smaller than the diameter W of the light dot 17on, that is, the light dot 17on is shifted by a distance H smaller than the diameter W of the light dot and superimposed on the photosensitive film 30a. By projecting twice, the entire pattern band 12b is exposed, and finally the entire pattern 12 is exposed. Thereby, it becomes possible to draw the outline of the pattern with a resolution lower than the light dot 17on. Therefore, it is possible to form a contour with less zigzag, and it is possible to improve the reproducibility of the curve and the reproducibility of the oblique line and form a highly accurate whole pattern. Further, when the entire pattern 12 or the entire pattern band 12b has periodicity, moire (periodic light / dark pattern) may occur depending on the relationship between the size of the light dot 17on and this cycle. Since a pattern with sufficiently higher resolution can be formed, moire is less likely to occur.

  Furthermore, since the entire pattern is exposed by shifting and overlapping the light dots 17on, it can be easily applied to a large substrate. Therefore, it is possible to realize a large color filter with good performance.

  In addition, since exposure is performed by projecting light dots using a spatial light modulator, the uniformity of the incident angle of light incident on the photosensitive film 30a is determined by scanning a point light source with a polygon mirror, so-called swinging, etc. It is extremely high compared to drawing. Therefore, there are few villages at the boundary of the light dots, the cross-sectional shape of the pattern of the photosensitive film 30a after development is almost uniform, for example, almost vertical, and unevenness in the joints such as the entire pattern band 12b is less likely to occur.

  Furthermore, since the light dots are projected using the spatial light modulator 60 in which a large number of light modulation elements 62 are arranged in a matrix, a large number of light dots 17on can be efficiently projected.

  Furthermore, in this embodiment, since the entire pattern band 12b is exposed so that the peripheral portions thereof overlap each other, the joint portion between the adjacent entire pattern bands 12b becomes less conspicuous, and unevenness caused by the joint can be further suppressed.

  In addition, in this embodiment, after development, cleaning is performed by obliquely applying droplets to the patterned film 30b, so that residues inevitably present in the openings after development can be efficiently removed, Patterning with less unevenness and moire is possible even with resolution patterns. In addition, when a droplet is applied vertically, the liquid flow stays on the substrate, so that the cleaning effect is reduced and cleaning unevenness becomes remarkable.

  Further, in the present embodiment, since the entire pattern band 12b is arranged in parallel using the spatial light modulator 60 (see FIG. 5), unevenness and moire due to the width of the entire pattern band 12 may occur. Such moire and unevenness can be reduced by the oblique cleaning.

  By these, it is possible to realize a large color filter with good performance.

  In the above embodiment, the stage 40 is moved relative to the spatial light modulator 60. However, the spatial light modulator 60 may be moved relative to the stage, or the stage 40 and the spatial light modulator 60 may be moved relative to each other. Also good.

  In particular, when the substrate is large, a plurality of combinations of the light source 50 and the spatial light modulator 60 may be provided.

  The moving distance H is not particularly limited as long as it is smaller than the diameter W of the light dot. When the moving distance H is reduced, the resolution is further increased.

  In addition, the whole pattern in the said embodiment is an illustration, and it cannot be overemphasized that the setting of the 2 gradation pattern of various shapes is possible as needed.

  Furthermore, in the above-described embodiment, the light dots are superimposed and exposed using a spatial light modulator capable of projecting a plurality of light dots, but a single stroke is written using an optical system capable of projecting only one light dot. Needless to say, the entire pattern may be formed by shifting and overlapping the light dots in the manner described above.

<Structure of color filter for liquid crystal display element>
Next, an example of a color filter CF and an example of a liquid crystal display LCD to which the manufacturing method of the present invention can be applied will be described with reference to FIG.

  The color filter CF partitions the transparent colored resin layers 73R, 73G, 73B, which are RGB subpixels as display units, and these transparent colored resin layers 73R, 73G, 73B on a transparent substrate 61 such as non-alkali glass. A black matrix 63 as a light shielding pattern is mainly formed.

  The black matrix 63 partitions the boundaries of the adjacent transparent colored resin layers 73R, 73G, and 73B to prevent color mixing, and requires extremely high pattern accuracy and uniformity. The shape of the black matrix 63 is generally a lattice shape or a stripe shape, but a refractive shape or a polygonal shape may be employed in order to increase the display resolution.

  The black matrix 63 may be a pattern obtained by patterning a thin film that is a combination of a light-shielding thin film made of metal such as chromium, molybdenum, and nickel and an anti-reflection film, and is also a light-shielding film in which carbon black, titanium compound, or ferrite compound is dispersed. It may be made of a functional resin. As the light-shielding resin, if it has a photosensitivity, it may be directly patterned by a photolithographic method. If it is not photosensitive, a resist mask is formed thereon and formed by various etching methods. May be.

  And in the manufacturing process of this black matrix 63, the manufacturing method which employ | adopted the above-mentioned patterning method can be used in patterning of a thin film or light-shielding resin, and patterning of a resist mask.

  In the opening of the black matrix 63, R (red), G (green), and B (blue) transparent colored resin layers 73R, 73G, and 73B are formed in a predetermined order.

  The transparent colored resin layers 73R, 73G, and 73B are formed in a pattern that covers the openings of the black matrix 63. For example, when one pixel is formed with RGB three-color stripes, the line width of the sub-pixel, that is, the opening width of the black matrix 63 is about 1/3 of the pitch of one pixel.

  Such transparent colored resin layers 73R, 73G, and 73B can also be manufactured by direct patterning of a photosensitive transparent colored resin or patterning using a resist mask provided on the transparent colored resin layer. Also, the above-described patterning method can be applied.

  Then, if necessary, a transparent flattening layer 80 for flattening the surface is provided on these transparent colored resin layers 73R, 73G, 73B, and further, a transparent conductive layer serving as a common electrode for driving liquid crystal. A film 85 is formed.

  The transparent flattening layer 80 is applied over the black matrix 63 / transparent colored resin layers 73R, 73G, 73B, and fills the steps of the transparent colored resin layers 73R, 73G, 73B and the black matrix 63, and is suitable for a liquid crystal cell. It provides smoothness and prevents the elution of contaminants from the color filter CF. In addition, the transparent planarization layer 80 may be subjected to fine patterning according to the necessity of designing the liquid crystal cell, and in this case, the above-described patterning method can be used.

  As the transparent conductive film 85, ITO or the like can be used. The surface of the transparent electrode film 85 may be subjected to slit processing (bank processing) as necessary, but this can also be performed by the patterning method described above.

  Further, as processing for improving the viewing angle characteristics, processing such as forming a bank for dividing the alignment direction of the liquid crystal on the transparent conductive film 85 or forming a slit in the transparent conductive film 85 itself is performed. In this case, the above-described patterning method can be applied.

  Further, columnar spacers 90 for adjusting the cell gap of the liquid crystal are formed on the transparent electrode film 85. The columnar spacer 90 can be formed by laminating the above black matrix, transparent colored resin layer, and transparent flattening layer pattern by photolithography, but it is necessary to manage the height accuracy and deformation characteristics very strictly. For this reason, it is generally performed that a dedicated photosensitive resin layer is repeatedly applied and a predetermined pattern is finished by photolithography. The above patterning method can also be applied to these steps.

  Further, an alignment film 86 is formed on the transparent conductive film 85 as necessary.

  On the transparent substrate 61, in addition to the black matrix 63, marks (not shown) for overlaying and bonding RGB colored layers and quality control may be formed.

  In the case of a transflective liquid crystal, the optical path length in the liquid crystal cell is twice that of the transmissive region in the reflective region. For this reason, in order to simultaneously optimize the display characteristics of the transmissive display and the reflective display, a different cell gap may be formed for each of the reflective portion and the transmissive portion in the reflective / transmissive liquid crystal panel. For example, it is a case where a raised layer is formed under the reflector. The patterning method described above can also be applied to this step.

  Then, the thin film transistor substrate TFT is disposed opposite to the color filter thus created, and the liquid crystal 120 is sealed between the alignment film 86 and the thin film transistor substrate TFT, thereby completing a liquid crystal display element as a flat display. To do. The thin film transistor substrate TFT has a pixel electrode 301 and an alignment film 87 on the lower surface of the thin film transistor element 300, and a polarizing film 115 is formed on the thin film transistor element 300.

  In such a color filter, the patterning method described above is used in forming the black matrix 63, the transparent colored resin layers 73R, 73G, and 73B, and the openings of the transparent flattening film 80, the transparent conductive film 85, the columnar spacer 90, and the like. As a result, a flat display having excellent visibility with no unevenness due to the joint can be obtained. Further, by this method, a resin layer (for example, novolak, acrylic, etc.) having an alignment regulating structure may be provided between the transparent conductive film and the alignment film, and a scattering layer or a microlens may be provided at any position on the liquid crystal panel. May be formed by this method.

  In particular, in the manufacture of such a color filter, for example, by performing as many exposure steps as possible in the photolithography process performed about 5 to 7 times with the above-described apparatus and method, the seam is more uniform, and A color filter and a flat display having an excellent cross-sectional shape can be obtained.

  The color filter described above can be applied not only to a color filter for a liquid crystal display but also to a color filter for a flat display using a white organic EL light emitting element or the like.

<Photosensitive material>
Subsequently, a photosensitive resin material for forming a photosensitive film when using the above-described method will be exemplified.

As the photosensitive resin material, either a negative photosensitive resin or a positive photosensitive resin can be used. Here, the negative photosensitive resin will be mainly described.

<Negative photosensitive material>
The negative photosensitive resin is one in which the irradiated part of light is insolubilized and remains in the developer, and generally contains additives such as a binder polymer, a photopolymerizable compound, a photoreaction initiator, a solvent, and a dispersant. In addition, those containing a coloring material and a light-shielding material as required are used.

<Photopolymerizable compound (crosslinking agent)>
The photopolymerizable compound is a compound that can be polymerized by an active radical, an acid, or the like generated from a photopolymerization initiator, and examples thereof include a compound having a polymerizable carbon-carbon unsaturated bond. The compound may be a monofunctional photopolymerizable compound or a bifunctional or trifunctional or higher polyfunctional photopolymerizable compound. Examples of the monofunctional photopolymerizable compound include nonylphenyl carbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexyl carbitol acrylate, 2-hydroxyethyl acrylate, N-vinyl pyrrolidone, and the like. Examples of the bifunctional photopolymerizable compound include 1,6-hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and bisphenol A. Bis (acryloyloxyethyl) ether, 3-methylpentanediol di (meth) acrylate, and the like. Examples of the tri- or higher functional photopolymerizable compound include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa. Examples include (meth) acrylate. A preferred photopolymerizable compound is dipentaerythritol hexa (meth) acrylate. The photopolymerizable compounds are used alone or in combination of two or more, but bifunctional or higher photopolymerizable compounds are preferably used. When two or more photopolymerizable compounds are used, at least one of them is used. It is preferable to use a bifunctional or higher photopolymerizable compound. The amount of the photopolymerizable compound used is usually 0.1 parts by mass or more and 70 parts by mass or less, preferably 1 part by mass or more and 60 parts by mass or less per 100 parts by mass of the total amount of the binder polymer and the photopolymerizable compound.

<Binder polymer>
As the binder polymer, a colorant and a light-shielding agent can be dispersed, and a transparent resin that imparts a crosslinkable function by light irradiation to the colored composition layer together with other components is used. Examples of the binder polymer include aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, Unsaturated carboxylic acid ester compounds such as benzyl (meth) acrylate, unsaturated carboxylic acid aminoalkyl ester compounds such as aminoethyl acrylate, unsaturated carboxylic acid glycidyl ester compounds such as glycidyl (meth) acrylate, vinyl acetate, vinyl propionate, etc. Carboxylic acid vinyl ester compounds, (meth) acrylonitrile, vinyl cyanide compounds such as α-chloroacrylonitrile, 3-methyl-3- (meth) acryloxymethyloxetane, 3-ethyl-3 Polymer of unsaturated carboxylic acid oxetane ester compounds such as-(meth) acryloxymethyl oxetane, 3-methyl-3- (meth) acryloxyethyl oxetane, 3-methyl-3- (meth) acryloxyethyl oxetane, A melamine acrylate resin, a polyester resin, etc. are mentioned.

  As the binder polymer, monomers may be used alone or in combination of two or more. Examples of the copolymer include benzyl methacrylate / methacrylic acid copolymer, styrene / methacrylic acid copolymer, 3-ethyl-3-methacryloxymethyloxetane / benzyl methacrylate / methacrylic acid copolymer, and 3-ethyl-3. -Methacryloxymethyl oxetane / methyl methacrylate / methacrylic acid copolymer, 3-ethyl-3-methacryloxymethyl oxetane / methyl methacrylate / methacrylic acid / styrene copolymer, and the like. In particular, a benzyl methacrylate / methacrylic acid copolymer is preferable. The content of the monomer unit having a carboxyl group in the copolymer is 5 to 50% by mass fraction, preferably 10 to 40%.

  The binder polymer preferably has a weight average molecular weight in the range of 5,000 to 400,000, more preferably in the range of 10,000 to 300,000 as determined by gel permeation chromatography (GPC) using polystyrene as a standard. . The binder polymer is generally used in a range of 5 to 90%, preferably 20 to 70% in terms of mass fraction with respect to the total solid content of the photosensitive resin.

<Photopolymerization initiator>
Examples of the photopolymerization initiator include active radical generators that generate active radicals when irradiated with light, such as acetophenone compounds, benzoin compounds, benzophenone compounds, thioxanthone compounds, and triazine compounds. It is done. Examples of the acetophenone compound include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 2-hydroxy-2-methyl-1- [4- (2-hydroxy Ethoxy) phenyl] propan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- And oligomers of (4-morpholinophenyl) butan-1-one and 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propan-1-one. Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3 ′, 4,4′-tetra (tert-butylperoxy). Carbonyl) benzophenone, 2,4,6-trimethylbenzophenone and the like. Examples of the thioxanthone compound include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, and the like. Examples of triazine compounds include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine and 2,4-bis (trichloromethyl) -6- (4- Methoxynaphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6-piperonyl-1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxy Styryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran-2-yl) ethenyl] -1,3,5-triazine, 2,4 -Bis (trichloromethyl) -6- [2- (furan-2-yl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (4-diethylamino- 2-methylpheny ) Ethenyl] -1,3,5-triazine, such as 2,4-bis (trichloromethyl) -6- [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine. Examples of the active radical generator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′- Biimidazole, 10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate, titanocene compounds, and the like can also be used. A commercially available thing can also be used as an active radical generator. Examples of commercially available photopolymerization initiators include trade name “Irgacure-907” (acetophenone photopolymerization initiator, manufactured by Ciba Specialty Chemicals). These photopolymerization initiators can be used alone or in combination of two or more. The usage-amount of a photoinitiator is 1 to 30 mass parts normally with respect to 100 mass parts of total amounts of a binder polymer and a photopolymerizable compound, Preferably they are 3 to 20 mass parts.

<Photopolymerization initiation aid>
The photopolymerization initiation assistant is a compound used in combination with the photopolymerization initiator to accelerate the polymerization of the photopolymerizable compound initiated by the photopolymerization initiator. Examples of the photopolymerization initiation assistant include amine compounds and alkoxyanthracene compounds. Examples of amine compounds include triethanolamine, methyldiethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, 2-dimethylhexyl 4-dimethylaminobenzoate, N, N-dimethylparatoluidine, 4,4'-bis (dimethylamino) benzophenone (commonly known as Michler's ketone), 4,4'-bis (diethylamino) benzophenone, 4,4'- And bis (ethylmethylamino) benzophenone. Examples of the alkoxyanthracene compound include 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 2-ethyl-9,10-diethoxyanthracene and the like. A commercially available photopolymerization initiation assistant can also be used, and examples of the commercially available photopolymerization initiation assistant include trade name “EAB-F” (manufactured by Hodogaya Chemical Co., Ltd.). When the photopolymerization initiation assistant is used, the amount used is usually 10 mol or less, preferably 0.01 mol or more and 5 mol or less, per mol of the photopolymerization initiator. When the photopolymerization initiator and the photopolymerization initiation assistant are used, the total amount is usually 1 part by mass or more and 30 parts by mass or less, preferably 100 parts by mass of the total amount of the binder polymer and the photopolymerizable compound, preferably 3 parts by mass or more and 20 parts by mass or less.

<Colorant>
Dyes and pigments can be used as colorants, and organic and inorganic pigments can be used as pigments. Specifically, they are classified as pigments by the Color Index (published by The Society of Dyers and Colorists). The compound which is mentioned.

<Shading material>
Examples of the light shielding material include organic pigments such as carbon, aniline black, and perylene compounds, and inorganic pigments such as titanium black and magnetite.

<Solvent>
Examples of the solvent include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether and ethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, and diethylene glycol diethylene ether. Diethylene glycol dialkyl ethers such as butyl ether, ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl Alkylene glycol alkyl ether acetates such as ether acetate, methoxybutyl acetate and methoxypentyl acetate, aromatic hydrocarbons such as benzene, toluene, xylene and mesitylene, aromatic aliphatic ethers such as anisole, phenetole and methylanisole, acetone, Ketones such as 2-butanone, 2-heptanone, 3-heptanone, 4-heptanone, 4-methyl-2-pentanone, cyclohexanone, alcohols such as ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, glycerin, Esters such as ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl lactate, methyl 2-hydroxyisobutyrate, cyclic such as γ-butyrolactone Examples include esters. These solvents can be used alone or in combination of two or more, and the content of the solvent in the photosensitive resin is usually 20% by mass to 90% by mass, preferably 50% by mass to 85% by mass. % To be used.

<Additives>
Examples of the additive include a filler, a polymer compound other than the binder polymer, a surfactant, an adhesion promoter, an aggregation inhibitor, an organic acid, and a curing agent. Examples of the surfactant include nonionic surfactants, cationic surfactants, anionic surfactants, and amphoteric surfactants. Examples of the adhesion promoter include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-amino). Ethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl Examples include trimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane.

<Positive photosensitive material>
On the other hand, a positive photosensitive material is one in which a light irradiation portion is solubilized in a developer, and is generally composed by combining a resin and a compound that becomes hydrophilic by a photoreaction. In the manufacture of filters, it is used to form an etching pattern by laminating thin films of metallic materials such as Cr and AL and inorganic materials such as ITO and IZO.

  As the positive photosensitive agent, a combination of a novolac resin, polyhydroxystyrene, acrylic resin, methacrylic resin, polyimide, or the like with a resin having chemical resistance and adhesion and a photodegradable compound can be suitably used.

<Example A>
A 20 cm square non-alkali glass (Dow Corning 1737, thickness 0.7 mm) is coated with a light-shielding photosensitive resin (manufactured by Tokyo Ohka Kogyo Co., Ltd .: BK-4617) and dried on a hot plate at 90 ° C. for 110 seconds. Then, a light-shielding resin film having a film thickness of 1.2 μm was formed.

  Using a direct image drawing machine (DI-2080, manufactured by PENTAX), the entire light-blocking resin film is exposed to a black matrix pattern of 120 μm × 360 μm pitch (line width 20 μm) by the above-described method. did.

Here, a partial pattern was generated by arranging 1024 × 780 light dots or dark dots of 10 μm × 10 μm. The shift amount H of the partial pattern was set to a value less than the light dot diameter. The exposure amount of the bright part in the entire pattern formed by overlapping the light dots many times was 10 mJ / cm ² .

  The light-shielding resin film after exposure was subjected to shower development at 23 ° C. for 80 seconds using an inorganic alkali developer (KOH 0.05%). Thereafter, using a microjet cleaning apparatus, droplets were ejected at pressures of 1, 2, 5, 10, 20, and 30 MPa to clean the developed film (Examples A1 to A6). Here, the droplet discharge nozzle was mounted so that θ = 15 ° in FIG. After cleaning the entire surface of the substrate for about 60 seconds, it was dried with an air knife and heat-treated at 220 ° C. for 20 minutes. Water was used as the liquid forming the droplets. The appearance evaluation results of the pattern for each droplet supply pressure are shown in FIG.

  In either case, moire was not observed, and the seam unevenness was sufficiently suppressed. In particular, when the pressure was 2 MPa or more, the seam unevenness was almost eliminated. On the other hand, when the pressure was 30 MPa, pattern loss sometimes occurred. The photograph of the pattern of Example A2 after preparation is shown in FIG.

  As shown in FIG. 9, each black matrix pattern after development had a uniform line width distribution.

<Example B>
On an alkali-free glass (Corning 1737: 370 × 470 mm), a low reflection chromium film (chromium oxide / metal chromium film: 0.2 μm), and ONPR-13 manufactured by Tokyo Ohka Kogyo Co., Ltd. as a photosensitive resin. A substrate coated in this order is prepared, and a zigzag slit pattern (bending angle ± 45 °, 150 μm × 300 μm pitch, slit width 10 μm) and a black matrix lattice pattern (110 μm × 330 μm pitch) with respect to the photosensitive resin. , Line width 12 μm). The exposure conditions were the same as Example A1 except that the exposure amount was 150 mJ / cm ² . The exposed photosensitive resin was shower-developed using an inorganic alkaline developer (KOH 0.5%), and further washed with oblique droplets at a pressure of 10 MPa for 60 seconds to obtain a resist pattern. Thereafter, the chromium film was further etched using a ceric ammonium nitrate solution using this resist pattern as a mask. The obtained patterning film is shown in FIGS. Although a pattern was formed using 10 μm square light dots, a smooth 10 μm wide zigzag (diagonal) pattern and a smooth 12 μm wide black matrix could be formed. Further, these patterns were generally free of moire and seam unevenness and uniform in width.

<Comparative Example 1>
As shown in FIG. 12, a partial pattern is formed on the surface of the photosensitive resin (photosensitive film 30a) of Example 1 by irradiating the polygon mirror 102 with laser light from the laser light source 100 and scanning it. By exposing the pattern while shifting the position, the entire pattern similar to the entire pattern of Example 1 was drawn. Cleaning with oblique droplets after development was not performed. The developed black matrix had a non-uniform cross section at the boundary of the partial pattern scanning region, resulting in a level difference, and discontinuous unevenness.

FIG. 1 is a schematic block diagram showing an exposure measure according to the embodiment. FIG. 2 is a schematic diagram regarding the entire pattern data. FIG. 3 is a plan view of partial pattern data. FIG. 4 is a schematic view showing a state in which exposure is performed while shifting a partial pattern on the photosensitive film. FIG. 5 is a perspective view showing a state in which a partial pattern is shifted on the photosensitive film and exposed while being overlapped to form an entire pattern band. FIG. 6 is a conceptual diagram showing how the patterned film is cleaned. FIG. 7 is a cross-sectional view showing a color filter and a liquid crystal display element created by exposure with the exposure apparatus of FIG. FIG. 8 is a table showing the conditions and results of Examples A1 to A6. FIG. 9 is an SEM photograph of the black matrix after development in Example A2. FIG. 10 is an SEM photograph of the zigzag pattern of the chromium film after development in Example B. FIG. 11 is an SEM photograph of the black matrix of the chromium film after development in Example B. FIG. 12 is a schematic diagram showing an exposure method of Comparative Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Whole pattern data, 12 ... Whole pattern, 12b ... Whole pattern belt | band | zone (whole pattern), 15 ... Partial pattern data, 17 ... Partial pattern, 17on ... Light dot, 30a ... Photosensitive film, 50 ... Light source, 60 ... Spatial light Modulator, 62 ... light modulation element, CF ... color filter.

Claims (6)

An exposure step of exposing the entire pattern to the photosensitive film; a development step of developing the photosensitive film exposed to the entire pattern to form a patterned film; and a cleaning step of cleaning the patterned film; A method of manufacturing a color filter comprising:
In the exposure step,
The overall pattern is projected by projecting light dots of a predetermined size onto the photosensitive film and projecting the light dots on the photosensitive film while shifting the light dots by a distance smaller than the diameter of the light dots. Exposed and
In the cleaning step, a color filter manufacturing method in which droplets are ejected obliquely with respect to the patterned film. In the exposure step,
Each of the light modulation elements using a spatial light modulator in which a plurality of light modulation elements that can select a state in which light dots are projected onto the photosensitive film or a state in which light dots are not projected onto the photosensitive film are arranged The partial pattern formed by the presence or absence of light dots according to the state of the exposure is superimposed on the photosensitive film while being shifted by a distance smaller than the diameter of the light dots with respect to the photosensitive film, thereby exposing the whole pattern. The method for producing a color filter according to claim 1.   The light modulation element selects either a first state in which light from a light source is reflected on the photosensitive film or a second state in which light from the light source is not reflected on the photosensitive film. The manufacturing method of the color filter of Claim 2.   The light modulation element selects either a first state in which light from a light source is transmitted to the photosensitive film or a second state in which light from the light source is not transmitted to the photosensitive film. The manufacturing method of the color filter of Claim 2.   The method for producing a color filter according to claim 1, wherein the color filter is a color filter for a flat display. The method for producing a color filter according to claim 1, wherein the photosensitive film after development is at least one of a black matrix, a transparent colored resin layer, an alignment regulation structure, a scattering layer, a microlens, or a spacer. .

Images