JPH0862416A - Pigment for color filter and manufacture of color filter - Google Patents

Abstract

PURPOSE: To provide a pigment for color filter which has heat resistance and light resistance, dissolves well in organic solvent, and does not contain alkali metal by composing it of a compound in which a specific group is introduced into dye. CONSTITUTION: It is a pigment composed of a compound in which N-3- hydroxypropylsulfamoil group is introduced into dye. For example, there are a magenta pigment having a composition shown in a formula I where N-3- hydroxypropylsulfamoil group is introduced into azo dye and a yellow pigment having a composition shown in a formula II. These pigments, for example, turn sodium sulfonate group into chlorosulfonate group by making chlorinated agent act upon a pigment having sodium sulfonate group called acid dye. The pigment for color filter can be obtained by making n-propylamine act upon it next. Moreover, the pigment may be reacted with n-propylamine after it is chlorosulfonated directly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter dye and a method for manufacturing a color filter using the color filter dye.

[0002]

2. Description of the Related Art A conventional color filter manufacturing method is
For example, there are a dyeing method and a color resist method. Among them, a dyeing method is often used for manufacturing a color filter such as a solid-state image sensor that requires a fine pattern. The dyeing method is a method of forming a pattern on a substrate and then immersing the substrate in an aqueous dye solution (hereinafter referred to as a dyeing solution) to dye the pattern.

However, the dyeing method has a drawback that the manufacturing process is complicated. Moreover, since the number of parameters that affect the spectral characteristics of the color filter is extremely large, there is a problem that it is very difficult to control the spectral characteristics.

On the other hand, the color resist method uses a coloring liquid containing a dye and a binder. Then, after applying the coloring liquid on the substrate, the coloring layer is patterned by a photolithography method to form a coloring pattern.
In this method, the patterning process is repeated for each color, but the pattern is heat-cured during each repeating process. Therefore, from the viewpoint of heat resistance during the heat curing treatment, a pigment is usually used as the dye.

Since the color resist method does not have a dyeing step, it is easy to control the spectral characteristics. Further, there is an advantage that the manufacturing process is simplified as compared with the dyeing method. Therefore, this method is becoming the mainstream in the manufacture of color filters for liquid crystal displays having large pixels.

[0006]

However, in the above color resist method, since the particle size of the pigment used for the dye is large, light scattering occurs at the time of exposure and the resolution deteriorates. Therefore, there is a problem that it is not suitable for an application such as a solid-state imaging device that requires a fine pattern. On the other hand, there is a dye as a pigment having a small particle size. Since the dye has a small particle size and high resolution, it is suitable for a color filter in which a fine pattern is formed.

However, in order to obtain a colored pattern having a thin film thickness (usually 2 μm or less) such as a color filter and having a sufficient concentration, it is necessary to dissolve a dye in a coloring liquid at a high concentration, but a dye having a good solubility is generally used. Has poor heat resistance and light resistance.
For example, disperse dyes and oil-soluble dyes are dyes having good solubility in organic solvents. However, most of them are sublimated or decomposed by heating, which causes a problem that the spectral characteristics of the formed color filter change.

Some dyes have an alkali metal such as sodium sulfonate group (--SO ₃ Na group). Such dyes may cause reliability problems in applications where solid metals such as solid-state image sensors do not like alkali metals.

The present invention has been made to solve the above-mentioned problems, and it has heat resistance and light resistance, has good solubility in organic solvents, and does not contain an alkali metal, and a dye for a color filter and the color. It is an object of the present invention to provide a method for manufacturing a color filter using a filter dye.

[0010]

A dye for a color filter of the present invention (hereinafter referred to as a dye of the present invention) for solving the above-mentioned problems has an N-3-hydroxypropylsulfamoyl group introduced into the dye. It is composed of compounds.

Further, in the method for producing a color filter of the present invention (hereinafter referred to as the method of the present invention), first, a coloring liquid containing the color filter dye and a binder is applied on a substrate to form a coloring layer. Then, the colored layer is patterned to form a pattern of the colored layer on the substrate.

Furthermore, the method of the present invention is a method in which the binder comprises a compound having a functional group that reacts with the N-3-hydroxypropylsulfamoyl group of the color filter dye. Further, in the method of the present invention, the functional group which reacts with the N-3-hydroxypropylsulfamoyl group is
The method is at least one of N-methylol group, N-alkoxymethyl group, halogenated alkyl group, isocyanate group, acid anhydride, chlorosulfone group, vinylsulfone group, epoxy group and carboxyl group.

[0013]

The dye of the present invention exhibits high solubility in organic solvents due to the hydroxyl group of N-3-hydroxypropylsulfamoyl group. Further, when the dye has heat resistance and light resistance, the heat resistance and light resistance hardly change even if the above-mentioned N-3-hydroxypropylsulfamoyl group is introduced into the dye. Furthermore, the dye of the present invention does not contain an alkali metal.

Further, in the method of the present invention, since the coloring liquid containing the dye of the present invention having high solubility in the organic solvent is used, the pattern of the colored layer having the required dye concentration is formed.
Furthermore, when the binder has a compound having a functional group that reacts with the N-3-hydroxypropylsulfamoyl group, when heat is applied to the colored layer in the step of forming the colored layer, N-3-hydroxypropylsulfamoyl group is used. The hydroxyl group of the moyl group and the above functional group are covalently bonded to form a polymer.

[0015]

EXAMPLES Examples of the dye of the present invention and the method of the present invention will be described below. In the present invention the dye, and its features, the dye in the dye N-3- hydroxypropyl sulfamoyl group _{(-SO 2 NHCH 2 CH 2 CH} 2 OH
Group) is introduced.

For example, a magenta dye having a structure shown in (Chemical formula 1) in which an N-3-hydroxypropylsulfamoyl group is introduced into an azo dye and a yellow dye having a structure shown in (Chemical formula 2) can be cited.

[0017]

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Further, a cyan dye having a structure shown in (Chemical Formula 3), for example, in which an N-3-hydroxypropylsulfamoyl group is introduced into a phthalocyanine dye, can be mentioned.

[Chemical 3]

Such a dye is produced, for example, by the following method. By the action of chlorinating agent to the dye having a sodium sulfonate group, which is so-called acid dye (-SO ₃ Na group), a sodium sulfonate group to chloro sulfonate group (-SO ₃ Cl group). Then, it can be obtained by reacting with n-propylamine (CH ₃ CH ₂ CH ₂ NH ₂ ). Alternatively, the dye may be directly chlorosulfonated and then reacted with n-propylamine.

The above-mentioned dye for color filter is a hydroxyl group (--OH of N-3-hydroxypropylsulfamoyl group).
Group) shows extremely high solubility in general polar organic solvents. Moreover, when the dye has heat resistance and light resistance, the heat resistance and light resistance hardly change even if the N-3-hydroxypropylsulfamoyl group is introduced. Further, since the particle diameter of the dye is small, it becomes possible to obtain high resolution during exposure. Further, since the color filter dye does not contain an alkali metal (for example, sodium), reliability problems do not occur when it is used for manufacturing a color filter.

Therefore, it is possible to realize a dye for a color filter which has high heat resistance and light resistance, high solubility in an organic solvent, and high resolution. Therefore, it is very effective for manufacturing a color filter that requires a fine pattern such as a solid-state imaging device using a color resist method.

Next, a first embodiment of the method of the present invention will be described with reference to the process drawing (No. 1) shown in FIG. 1 and the process drawing (No. 2) shown in FIG. This invention is a method of using a dye for a color filter, which comprises a compound in which the above N-3-hydroxypropylsulfamoyl group is introduced into a dye.

Prior to production, a coloring liquid as shown in, for example, (Table 1) containing the color filter dye and the binder polymer is prepared for each color of magenta, yellow and cyan. Note that magenta, yellow, and
The cyan dyes have the structures shown in (Chemical Formula 1), (Chemical Formula 2), and (Chemical Formula 3). Further, in this example, a compound having a functional group that reacts with the hydroxyl group of the N-3-hydroxypropylsulfamoyl group is used as the binder polymer forming the coloring liquid.

The functional group which reacts with the hydroxyl group of the N-3-hydroxypropylsulfamoyl group is N-methylol group,
It comprises at least one of an N-alkoxymethyl group, a halogenated alkyl group, an isocyanate group, an acid anhydride, a chlorosulfone group, a vinylsulfone group, an epoxy group and a carboxyl group. The binder polymer shown in (Table 1) shows an example of a compound having an epoxy group, for example. Further, a coloring liquid is prepared and a thermosetting resin solution composed of the elements shown in (Table 2) and a negative resist composed of the elements shown in (Table 3) are prepared.

[0025]

[Table 1]

[Table 2]

[Table 3]

First, as shown in FIG. 1A, the thermosetting resin solution is applied to the surface of the wafer 1 on which a solid-state image pickup device (not shown) is formed in advance. Then, it heat-processes and a solvent is removed and it hardens | cures and the planarization layer 2 is formed.
In FIG. 1A, reference numeral 1a indicates a scribe portion, and reference numeral 1b indicates a bonding pad.

Then, as shown in FIG. 1B, the magenta coloring liquid is applied onto the wafer 1 using the wafer 1 on which the flattening layer 2 is formed as a base. Then, heat treatment is performed to remove the solvent and heat cure to form the magenta colored layer 3. Further, the negative resist film is formed on the magenta colored layer 3, and the first resist pattern 4 is formed by photolithography.

Next, as shown in FIG. 1C, etching is performed using the first resist pattern 4 as a mask to pattern the magenta colored layer 3. Then, the magenta filter 5 having the pattern of the magenta colored layer 3 is formed.

Next, as shown in FIG. 1D, the flattening layer 2 excluding the scribe portion 1a and the bonding pad 1b.
The negative resist is newly applied on the top surface to form the first intermediate layer 6. At this time, the first intermediate layer 6 is formed so as to cover the magenta filter 5.

After the formation of the first intermediate layer 6, as shown in FIG.
The step shown in (c) is similarly performed using the yellow coloring liquid. Then, as shown in FIG. 2E, a yellow filter 7 having a pattern of a yellow colored layer is formed. When etching is performed using the pattern 4 of the negative resist as a mask, the unnecessary portion of the flattening layer 2 is removed by etching with the first intermediate layer 6 as a mask together with the formation of the yellow filter 7.

Next, as shown in FIG. 2F, the second intermediate layer 8 made of the above negative resist is formed on the first intermediate layer 6 excluding the scribe portion 1a and the bonding pad 1b. At this time, the second filter is formed so as to cover the yellow filter 7.
The intermediate layer 8 is formed.

After the formation of the second intermediate layer 8, as shown in FIG.
The step shown in (c) is similarly performed using the cyan coloring liquid. Then, as shown in FIG. 2G, a cyan filter 9 having a pattern of a cyan colored layer is formed. When etching is performed with the negative resist pattern 4 as a mask, the cyan filter 9 is formed and the planarization layer 2 is formed.
The unnecessary portions of are removed by etching using the second intermediate layer 8 as a mask.

Then, as shown in FIG. 2G, the overcoat layer 1 made of the above negative resist is formed on the second intermediate layer 8 excluding the scribe portion 1a and the bonding pad 1b.
Form 0. At this time, the overcoat layer 10 is formed so as to cover the cyan filter 9. By the above process,
A color filter 11 including a magenta filter 5, a yellow filter 7 and a cyan filter 9 is manufactured on the wafer 1 on which the solid-state image sensor is formed.

In the first embodiment described above, a coloring liquid composed of a dye for a color filter which is well dissolved in an organic solvent is used. Therefore, the magenta filter 5, the yellow filter 7, and the cyan filter 9 having the required dye density can be formed even when the color filter 11 having a small film thickness is manufactured.

Further, since the color filter dye has heat resistance and light resistance, each dye concentration in the color liquid is maintained even when the color liquid applied to the wafer 1 is cured by heating. Further, since the color filter dye does not contain an alkali metal, the color filter 11 in which reliability troubles due to the alkali metal do not occur is formed.

In the first embodiment, a compound having an epoxy group is used as the binder polymer which is a constituent of the coloring liquid. Therefore, when the coloring liquid is heated and cured, the hydroxyl group of the N-3-hydroxypropylsulfamoyl group of the color filter dye and the epoxy group are covalently bonded to form a polymer as shown in (Chemical Formula 4). In addition, in (Chemical formula 4),
The portion of the dye other than the N-3-hydroxypropylsulfamoyl group and the portion of the binder polymer other than the epoxy group are omitted.

As a result, it is possible to form the color filter 11 having improved heat resistance as compared with the conventional one. Moreover, when the magenta filter 5, the yellow filter 7, and the cyan filter 9 are sequentially formed, the dye of the formed filter can be prevented from being eluted in a later step. The hydroxyl group of the N-3-hydroxypropylsulfamoyl group and the binder polymer effectively react with each other only by heating, but if necessary, a catalytic action of acid or alkali may be used.

Further, in the first embodiment, the color filter 11 can be formed only by repeatedly forming the colored layer and patterning the colored layer by the photolithography method and the etching method for each color. Therefore, the manufacturing process of the color filter 11 can be simplified. Therefore,
According to the first embodiment, the color filter 11 having desired spectral characteristics can always be stably manufactured by the simplified manufacturing process.

Next, a second embodiment of the method for manufacturing a color filter of the present invention will be described with reference to the process drawing (No. 1) shown in FIG. 3 and the process drawing (No. 2) shown in FIG. This example is a method for producing a color filter in which a coloring liquid containing a color filter dye having an N-3-hydroxypropylsulfamoyl group and a binder polymer is made to have photosensitivity.

First, prior to manufacturing, a coloring liquid as shown in (Table 4) is prepared for each color of magenta, yellow and cyan. The magenta, yellow, and cyan dyes in (Table 4) have the structures shown in (Chemical formula 1), (Chemical formula 2), and (Chemical formula 3). Further, (Table 4) shows an example in which a compound having a carboxyl group that reacts with the hydroxyl group of the N-3-hydroxypropylsulfamoyl group is used as a binder polymer. Further, as shown in (Table 4), the colored liquid is made to have photosensitivity by using a photopolymerization monomer, a thermal photopolymerization initiator and a thermal photopolymerization accelerator as constituent elements.

In addition to preparing such a coloring liquid, a thermosetting resin solution (hereinafter referred to as a first resin solution) shown in (Table 2) similar to that of the first embodiment is shown in (Table 5). A thermosetting resin solution composed of elements (hereinafter referred to as a second resin solution) is prepared. Furthermore, the same negative resist as shown in (Table 3) as in the first embodiment is prepared.

[0042]

[Table 4]

[Table 5]

First, as shown in FIG. 3A, a wafer 1 similar to that of the first embodiment is used, and a flattening layer 2 made of the first resin solution is formed on the surface of the wafer 1. Then, FIG. 3 (b)
As shown in FIG. 2, the magenta coloring layer 13 is formed by coating the wafer 1 on which the flattening layer 2 is formed with the magenta coloring liquid on the wafer 1.

Subsequently, as shown in FIG. 3C, the magenta coloring layer 13 is patterned by the photolithography method. For example, the portion where the magenta filter 15 is to be formed is exposed and photocured. Then, the uncured portion is removed using a developing solution. Then, post-baking is further performed to heat the patterned magenta colored layer 13 to form a magenta filter 15.

Next, as shown in FIG. 3D, the flattening layer 2
A first intermediate layer 16 made of the second resin solution is formed on the top. At this time, the first intermediate layer 16 is formed so as to cover the magenta filter 15. Further, after the formation of the first intermediate layer 16,
The steps shown in FIGS. 3B and 3C are similarly performed using the yellow coloring liquid. Then, the yellow filter 17 having the pattern of the yellow colored layer is formed.

Then, as shown in FIG. 4F, the second intermediate layer 18 made of the second resin solution is formed on the first intermediate layer 16.
To form. At this time, the second intermediate layer 18 is formed so as to cover the yellow filter 17. After that, as shown in FIG.
The step shown in (c) is similarly performed using the above cyan coloring liquid to form a cyan filter 1 having a pattern of a cyan coloring layer.
9 is formed.

Subsequently, as shown in FIG. 4F, the overcoat layer 20 made of the above negative resist is formed on the second intermediate layer 18 excluding the scribe portion 1a and the bonding pad 1b. At this time, the overcoat layer 20 is formed so as to cover the cyan filter 19.

Then, as shown in FIG. 4G, unnecessary portions of the planarizing layer 2, the first intermediate layer 16 and the second intermediate layer 18 are removed by etching using the overcoat layer 20 as a mask. Through the above steps, the color filter 21 including the magenta filter 15, the yellow filter 17, and the cyan filter 19 is manufactured on the wafer 1 on which the solid-state image sensor is formed.

In the second embodiment, since the coloring liquid having photosensitivity is used, the magenta filter 15, the yellow filter 17 and the cyan filter 19 can be formed only by exposing and developing the coloring layer. Therefore, the manufacturing process of the color filter 21 can be further simplified.

In addition, since a color filter dye capable of obtaining a high resolution is used at the time of exposure, the color filter 21 having a fine pattern can be formed. Moreover, since the color filter dye has heat resistance, light resistance, and good solubility in organic solvents, it is possible to always stably manufacture the color filter 21 having desired spectral characteristics.

In the second embodiment, a compound having a carboxyl group is used as the binder polymer which is a constituent of the coloring liquid. Therefore, at the time of heat curing after development,
As shown in (Chemical Formula 5), N-3-
The hydroxyl group of the hydroxypropylsulfamoyl group and the carboxyl group covalently bond to form a polymer. In (Chemical Formula 5), the portion of the dye other than the N-3-hydroxypropylsulfamoyl group and the portion of the binder polymer other than the carboxyl group are omitted. As a result, the color filter 21 having improved heat resistance can be formed. Further, it is possible to completely prevent the elution of the dye during the formation of each filter.

[0052]

As described above, the dye of the present invention is N-
Due to the hydroxyl group of the 3-hydroxypropylsulfamoyl group, it has high solubility in organic solvents. Moreover, since the N-3-hydroxypropylsulfamoyl group is introduced into the dye, a dye having heat resistance and light resistance of the dye and exhibiting high resolution at the time of exposure can be realized. Therefore,
This is very effective for manufacturing a color filter that requires a fine pattern using the color resist method. Further, since the dye of the present invention does not contain an alkali metal, it is suitable for applications where an alkali metal is disliked, such as a solid-state image sensor.

Further, since the method of the present invention uses the coloring liquid containing the above-mentioned dye of the present invention which exhibits good solubility in an organic solvent, it is possible to form a colored layer pattern having a required dye concentration. Further, the pattern of the colored layer can be formed only by the steps of forming the colored layer and patterning the colored layer. Therefore, a color filter having a fine pattern can be stably manufactured with a desired spectral characteristic by a simplified manufacturing process.

Further, when the binder is a compound having a functional group which reacts with the N-3-hydroxypropylsulfamoyl group, the hydroxyl group of the N-3-hydroxypropylsulfamoyl group and the above-mentioned functional group are used in the production process. And become high molecular weight. Therefore, a color filter having improved heat resistance can be formed.

[Brief description of drawings]

FIG. 1 is a process diagram (1) showing a first embodiment of the method of the present invention.

FIG. 2 is a process diagram (No. 2) showing the first embodiment of the method of the present invention.

FIG. 3 is a process drawing (1) showing a second embodiment of the method of the present invention.

FIG. 4 is a process diagram (2) showing the second embodiment of the method of the present invention.

[Explanation of symbols]

 1 Wafer (Substrate) 3 Magenta Colored Layer 5, 15 Magenta Filter (Colored Layer Pattern) 7, 17 Yellow Filter (Colored Layer Pattern) 9, 19 Cyan Filter (Colored Layer Pattern) 11, 21 Color Filter

[Chemical 4]

[Chemical 5]

Claims (4)

[Claims] 1. A dye for a color filter, comprising a compound in which an N-3-hydroxypropylsulfamoyl group is introduced into the dye. 2. A method for producing a color filter using the color filter dye according to claim 1, wherein a colored liquid containing the color filter dye and a binder is applied onto a substrate to form a colored layer. And a step of patterning the colored layer to form a pattern of the colored layer on the substrate, the method for producing a color filter. 3. The method for manufacturing a color filter according to claim 2, wherein the binder is N-3- of the color filter dye.
A method for producing a color filter comprising a compound having a functional group that reacts with a hydroxypropylsulfamoyl group. 4. The method for producing a color filter according to claim 3, wherein the functional group is an N-methylol group, an N-alkoxymethyl group, a halogenated alkyl group, an isocyanate group, an acid anhydride, a chlorosulfone group, A method for producing a color filter, which comprises at least one of a vinyl sulfone group, an epoxy group and a carboxyl group.