JP2017116856A - Coloring material-containing photosensitive composition, and color filter and solid-state image sensor using the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coloring material-containing photosensitive composition having high solubility with an alkali developer, capable of reducing a residue after development and having good productivity, and a color filter and a solid-state image sensor using the composition.SOLUTION: The coloring material-containing photosensitive composition is to be used for a solid-state image sensor, and the composition comprises at least a coloring material, a dispersant, a polymer, a photopolymerization initiator, a photopolymerizable monomer and a solvent. The photopolymerizable monomer comprises an acrylic compound having at most two unsaturated bond groups in one molecule and an acrylic compound having at least three unsaturated bond groups in one molecule; and the acrylic compound having at most two unsaturated bond groups in one molecule is included by 10 mass% or more and 30 mass% or less in the whole amount of the photopolymerizable monomer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a colorant-containing photosensitive composition used for a color filter formed on a photoelectric conversion element typified by CMOS or CCD, and a color filter formed on a photoelectric conversion element using the same, The present invention relates to a solid-state imaging device including a color filter.

  In general, a solid-state imaging device typified by a CCD or a CMOS includes a plurality of pixels arranged two-dimensionally. In a solid-state imaging device that reads a color image, color light is separated into three colors of green, blue, and red by passing incident light through the green, blue, and red colored layers of the color filter. Detection is performed by a photoelectric conversion element included in each pixel. In this way, the solid-state imaging device outputs an image signal including color information. A color filter used in a solid-state imaging device is directly formed on a semiconductor substrate on which a photoelectric conversion element such as a photodiode is formed via a planarization layer. Therefore, a color filter for a solid-state imaging device is often called an on-chip color filter.

  The on-chip color filter can be formed using a photolithography method in the same manner as a general color filter manufacturing method. A photosensitive composition containing a colorant, that is, coating a resist solution on a substrate, pre-baking, and pattern exposure of a coating film are sequentially performed, and then an unexposed portion of the coating film is removed in a development process using an alkali developer. Remove and bake the remaining coating. Thereby, the colored layer which consists of a some filter segment is obtained. In this way, the first colored layer is formed, and then the second and third colored layers are sequentially formed by the same method.

  Here, an example of the color filter array in plan view of the color filter for the solid-state imaging device is shown in FIG. In FIG. 1, only the portion of 6 rows and 6 columns is shown for convenience, but the whole is n rows and m columns (n and m are arbitrary natural numbers). In this color filter array, a rectangular green filter G is arranged in a checkered pattern so as to be in contact with the four sides of the rectangular blue filter B. Similarly, a rectangular green filter G is arranged in a checkered pattern so as to contact four sides of the rectangular red filter R.

  In recent years, in a color filter for a solid-state imaging device, an increase in the number of pixels, that is, a reduction in pixel size, has been demanded for further high-definition of an image. Many of the color filters have a pixel size of less than 2 μm × 2 μm, and there is a problem that a defective pattern shape or residue of the color filter formed by the photolithography process adversely affects the characteristics of the solid-state imaging device.

  In addition, with the miniaturization of pixels, it is necessary to reduce the thickness of the color filter. This is because, even if the pixel size of the color filter is reduced, if the film thickness remains large, the resolution is lowered and the distance to the light receiving element tends to be relatively long. If it is a thin color filter, the resolution is high, the productivity is excellent, and the distance between the microlens provided for light collection and the light receiving element is reduced, so that the device characteristics can be improved.

  However, the spectral characteristics need to be maintained even when the film thickness is reduced. Therefore, attempts have been made to increase the colorant content in the total solid content of the colorant-containing photosensitive composition.

  When a pixel pattern is created using a photosensitive composition having an increased colorant content, the amount of components that are soluble in an alkali developer in the photosensitive composition is reduced by the amount of increased colorant. Solubility in alkaline developer is reduced. For this reason, the portion that should originally be removed (the non-effective portion of the pixel) cannot be completely removed, resulting in a residue, and the shape of the edge of the square pixel pattern after development is liable to collapse, thereby obtaining pattern linearity. It becomes difficult to be.

  Furthermore, the finer the pixel pattern, the smaller the contact area of the unexposed area with the alkaline developer, and the lower the solubility of the photosensitive composition in the alkaline developer, the poorer the dissolution and the more likely residue is left.

  Since the residue of the resist that has been previously colored remains in the pixel portions of other colors, noise is increased in the reproduced image of the solid-state imaging device, the roughness is noticeable, and the image quality is impaired. In particular, if the pattern of the second color or the pattern of the third color enters the residue after the pattern of the first color is created, it may cause color mixing or color unevenness, resulting in a decrease in sensor sensitivity and color reproducibility. Characteristics are degraded.

  Accordingly, there is a need for a colorant-containing photosensitive composition that has no residue and maintains high sensitivity when a sensor is formed.

  Various measures have been taken to improve alkali developability in order to improve the problem of the residue.

  For example, an attempt is made to remove the residue using a rinse solution heated after development (Patent Document 1). However, energy is consumed due to heating of the rinsing liquid, and there is a concern about the influence on the manufacturing cost.

  In addition, in order to improve alkali developability, studies have been conducted to introduce a carboxyl group into a photopolymerizable monomer (Patent Documents 2, 3, and 4). However, the effect is not exhibited with other monomers having no carboxyl group. Moreover, since it has an acidic functional group, although the time required for development of the formed coating film is shortened, there is a problem that the number of functional groups necessary for photopolymerization tends to be reduced and the exposure sensitivity is lowered.

  When the exposure sensitivity is lowered, it is necessary to irradiate a larger amount of exposure, the exposure time becomes longer, and the production yield is significantly reduced.

  The exposure sensitivity can be increased by using a polyfunctional photopolymerizable monomer having a large number of functional groups, but many polyfunctional photopolymerizable monomers have a high molecular weight and are difficult to dissolve in an alkali developer, and the residue is It becomes easy to remain.

JP 2013-210542 A Japanese Patent Laid-Open No. 10-62986 JP 2009-244807 A JP 2013-228727 A

  The present invention has been made in view of the above problems, and has a coloring material-containing photosensitive composition that has high solubility in an alkaline developer, can reduce residues after development, and has good productivity, and the same. An object is to provide a color filter and a solid-state imaging device.

  As a result of intensive studies, the inventors of the present invention contain an acrylic compound having 2 or less unsaturated bond groups in one molecule and an acrylic compound having 3 or more unsaturated bond groups in one molecule. A colorant-containing photosensitive composition containing 10% by mass or more and 30% by mass or less of a photopolymerizable monomer in an acrylic compound having 2 or less saturated bonding groups in one molecule is used for a color filter for a solid-state imaging device. Thus, it has been found that since the exposure sensitivity is high and the solubility in an alkaline developer is high, the generation of residues after development can be suppressed. The present invention has been made based on such findings.

  That is, the present invention is a colorant-containing photosensitive composition comprising at least a colorant, a dispersant, a polymer, a photopolymerization initiator, a photopolymerizable monomer, and a solvent, wherein the photopolymerizable property The monomer contains an acrylic compound having 2 or less unsaturated bond groups in one molecule and an acrylic compound having 3 or more unsaturated bond groups in one molecule, and 2 unsaturated bond groups in one molecule. The acrylic compound having 10 or less and 30% by mass or less of the total amount of the photopolymerizable monomer, and the molecular weight of the acrylic compound having 2 or less unsaturated bond groups in one molecule is 200 or more and 400 or less. The unsaturated bond equivalent of the acrylic compound having 3 or more unsaturated bond groups in one molecule is 80 g / equivalent or more and 200 g / equivalent or less.

  Further, after the pixel pattern is formed, the residue present in the unexposed pixel pattern portion may occupy an area of 5% or less with respect to the area of the single pixel pattern.

  Moreover, this invention is comprised by the colored layer which consists of a cured film of the said coloring material containing photosensitive composition, It is a color filter characterized by the above-mentioned.

  Moreover, this invention is a solid-state image sensor provided with the said color filter.

  According to the present invention, a coloring material-containing photosensitive composition that is highly soluble in an alkali developer, can reduce residues after development, and has good productivity, and a color filter and a solid-state imaging device using the same. It can be realized.

Sectional drawing which shows typically an example of the solid-state image sensor which concerns on this embodiment The figure which shows an example of arrangement | sequence of three colors (red, blue, green) by the planar view of the color filter for solid-state image sensors

  Hereinafter, a colorant-containing photosensitive composition according to an embodiment of the present invention, a color filter using the same, and a solid-state imaging device will be described in detail.

  The photosensitive composition of this embodiment contains at least a colorant, a dispersant, a photopolymerizable monomer, a polymer, a photopolymerization initiator, and a solvent.

  As the coloring material, those which develop red, green and blue are mainly used. Specifically, as the green coloring material, a green pigment or an intermediate thereof can be used. Examples of the green pigment include C.I. I. Pigment Green 7, 36, 37, 58 can be used alone or in combination.

  Examples of the blue coloring material include C.I. I. Blue pigments such as CI Pigment Blue 15, 15: 3, 15: 4, 15: 6, 6, 22, and 60 can be used.

  Examples of the red coloring material include C.I. I. Red pigments such as CI Pigment Red 123, 155, 168, 177, 180, 217, 220, and 254 can be used.

  Furthermore, a yellow coloring material can be added to the red coloring layer and the green coloring layer, or a yellow coloring layer can be overlaid. Examples of the yellow coloring material include C.I. I. Yellow pigments such as CI Pigment Yellow 138, 139, 150, and 185 can be used alone or in combination.

  When the colorant-containing photosensitive composition is cured, it is typically adjusted so that a cured product having a pigment concentration in the range of 50% by mass to 70% by mass is formed. A high-definition color filter for a solid-state imaging device needs to have a thin film thickness as the pattern becomes finer, and color characteristics cannot be maintained unless the pigment concentration is within the above range.

  Any dispersant may be used as long as it can uniformly disperse the pigment. In particular, a dispersant or the like that has both a site that adsorbs to the pigment and a site that is compatible with the polymer is preferably used.

  As the photopolymerizable monomer, at least an acrylic compound having 2 or less unsaturated bond groups in one molecule and an acrylic compound having 3 or more unsaturated bond groups in one molecule are used.

  Examples of the acrylic compound having 2 or less unsaturated bond groups per molecule include, for example, phenol EO modified acrylate, phenylphenol EO modified acrylate, nonylphenol EO modified acrylate, ethylhexyl EO modified (n≈2) acrylate, acryloyloxyethylhexa Hydrophthalimide, bisphenol F EO modified (n≈2) diacrylate, bisphenol A EO modified (n≈2) diacrylate, isocyanuric acid EO modified diacrylate, polypropylene glycol diacrylate, polyethylene glycol diacrylate, or one of them Mixtures containing the above can be used.

  The molecular weight of the acrylic compound having 2 or less unsaturated bond groups in one molecule is preferably in the range of 200 or more and 400 or less. When the molecular weight is smaller than 200, the pattern is easily scraped by development after the exposure process, which may be one of the factors of pattern formation film thickness variation. On the other hand, when the molecular weight is larger than 400, it is difficult to dissolve in an alkaline developer, and a residue tends to remain. More preferably, it is 200 or more and 300 or less.

  The molecular weight and average molecular weight of the monomer specified in the present specification are expressed by theoretical values converted from atomic weights. The first decimal place was calculated as a significant figure, and the calculated value was rounded off to exclude the minority.

  Examples of acrylic compounds having three or more unsaturated bond groups in one molecule include pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, trimethylolpropane PO-modified (n = 1) triacrylate, and trimethylolpropane. PO modified (n = 2) triacrylate, trimethylolpropane EO modified (n = 1) triacrylate, trimethylolpropane EO modified (n = 2) triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, pentaerythritol Tetraacrylate, ditrimethylolpropane tetraacrylate, isocyanuric acid EO-modified triacrylate, isocyanuric acid EO-modified citriacrylate, and , It is possible to use a mixture containing one or more of them.

  The unsaturated bond equivalent of the acrylic compound having 3 or more unsaturated bond groups in one molecule is preferably in the range of 80 g / equivalent to 200 g / equivalent. When the unsaturated bond equivalent is smaller than 80, the exposure sensitivity becomes too high when forming a pattern, and the amount of change in the line width with respect to the exposure amount is large, which is one of the causes of line width variation. On the other hand, when the unsaturated bond equivalent is larger than 200 g / equivalent, the exposure sensitivity becomes too low, it is necessary to irradiate a large amount of exposure, the exposure time becomes long, and the production yield decreases significantly. If the exposure sensitivity is too low, the coating film is not completely photocured in the exposure process, and the pattern is easily scraped in the development process, which becomes one of the causes of variations in film thickness in pattern formation. More preferably, it is 100 g / equivalent or more and 170 g / equivalent or less.

The unsaturated bond equivalent defined in this specification is a measure of the amount of unsaturated bonds contained in a molecule. If the photosensitive resin has the same molecular weight, the smaller the value of the unsaturated bond equivalent, the lower the value. The amount of saturated bonds introduced increases. It is the weight per 1 mol of unsaturated bonds of the compound and is calculated by the following formula. The more unsaturated bonds per unit weight, the smaller the value of unsaturated bond equivalent.
Unsaturated bond equivalent = weight of compound (g) / number of moles containing unsaturated bond of compound

  In the above formula, the value calculated from the value in the manufacturer catalog or the chemical structural formula can be adopted as the molecular weight of the polymerizable compound and the number of polymerizable unsaturated bonds.

  The acrylic compound having 2 or less unsaturated bond groups in one molecule is preferably in the range of 10% by mass to 30% by mass with respect to the total amount of the photopolymerizable monomer. When the acrylic compound having 2 or less unsaturated bond groups in one molecule is smaller than 10% by mass, the acrylic compound having 3 or more unsaturated bond groups in one molecule is too much, and the exposure sensitivity is high. Therefore, the amount of change in the line width with respect to the exposure amount is large, which is one of the causes of line width variation. In addition, many acrylic compounds having three or more unsaturated bonding groups in one molecule have a high molecular weight, are difficult to dissolve in an alkaline developer, and a residue tends to remain.

  When the acrylic compound having 2 or less unsaturated bond groups in one molecule is larger than 30% by mass, the time required for development of the formed coating film is shortened, but the number of functional groups necessary for photopolymerization is reduced. The exposure sensitivity is too low. When the exposure sensitivity becomes too low, it is necessary to irradiate a large amount of exposure, the exposure time becomes long, and the manufacturing yield decreases significantly. If the exposure sensitivity is too low, the coating film is not completely photocured in the exposure process, and the pattern is easily scraped in the development process, which becomes one of the causes of variations in film thickness in pattern formation.

  As the polymer, for example, a thermoplastic resin, a thermosetting resin, an active energy curable resin, or a mixture containing two or more thereof can be used.

  Examples of the thermoplastic resin include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane resin, and polyester resin. , Acrylic resin, alkyd resin, polystyrene resin, polyamide resin, rubber resin, cyclized rubber resin, celluloses, polyethylene (HDPE, LDPE), polybutadiene, polyimide resin, or a mixture containing one or more thereof Can be used. Among them, an acrylic resin having good transparency is preferably used.

  As the thermosetting resin, for example, an epoxy resin, a benzoguanamine resin, a rosin-modified maleic acid resin, a rosin-modified fumaric acid resin, a melamine resin, a urea resin, a phenol resin, or a mixture containing at least one of them is used. be able to.

  Examples of the active energy curable resin include an acrylic compound having a reactive substituent such as an isocyanate group, an aldehyde group, and an epoxy group on a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, and an amino group, or A product obtained by reacting a methacrylic compound or cinnamic acid to introduce an acryloyl group, a methacryloyl group or a styryl group photocrosslinkable group into the linear polymer can be used. Further, a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer and an α-olefin-maleic anhydride copolymer is used as an acrylic compound or methacrylic compound having a hydroxyl group such as hydroxyalkyl acrylate and hydroxyalkyl methacrylate. You may use what is half-esterified with a compound.

  The polymer is obtained by copolymerizing several types of monomers and oligomers. Monomers and oligomers that produce polymers include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, β-carboxyethyl (Meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate , Pentaerythritol tri (meth) acrylate, glycidyl (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, bisphenol Diglycidyl ether di (meth) acrylate, neopentyl glycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, ester acrylate, methylolated melamine (meth) acrylic Various acrylic acid esters and methacrylic acid esters such as acid esters, epoxy (meth) acrylates, urethane acrylates, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) Examples include acrylamide, N-hydroxymethyl (meth) acrylamide, N-vinylformamide, acrylonitrile and the like. These can be used alone or in admixture of two or more.

  It is desirable that the polymer is obtained by copolymerizing a monomer having an acidic group so as to be dissolved in an alkali developer. As the acidic group, a carboxyl group is mainly used. As the carboxyl group-containing monomer, for example, in an unsaturated monocarboxylic acid, unsaturated dicarboxylic acid, unsaturated polycarboxylic acid or other unsaturated polycarboxylic acid in a molecule. And unsaturated carboxylic acids having at least one carboxyl group. Here, examples of the unsaturated monocarboxylic acid include acrylic acid, methacrylic acid, crotonic acid, α-chloroacrylic acid, and cinnamic acid. Examples of the unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid. The unsaturated polyvalent carboxylic acid may be an acid anhydride thereof, specifically maleic anhydride, itaconic anhydride, citraconic anhydride and the like. The unsaturated polyvalent carboxylic acid may be a mono (2-methacryloyloxyalkyl) ester such as succinic acid mono (2-acryloyloxyethyl) or succinic acid mono (2-methacryloyloxy). Ethyl), mono (2-acryloyloxyethyl) phthalate, mono (2-methacryloyloxyethyl) phthalate, and the like. The unsaturated polyvalent carboxylic acid may be a mono (meth) acrylate of a dicarboxy polymer at both ends thereof, and may be, for example, ω-carboxypolycaprolactone monoacrylate, ω-carboxypolycaprolactone monomethacrylate, or the like. These carboxyl group-containing monomers can be used alone or in admixture of two or more.

  Examples of the photopolymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, and 2-methyl-1- [4- (methylthio) phenyl] -2 -Acetophenone photopolymerization such as morpholinopropan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin photopolymerization initiators such as benzyldimethyl ketal, benzophenone, benzoylbenzoic acid, benzo Benzophenone photopolymerization initiators such as methyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, and 4-benzoyl-4′-methyldiphenyl sulfide, thioxanthone, 2-chlorothioxanthone, 2-methylthio Thioxanthone photopolymerization initiators such as xanthone, isopropylthioxanthone, and 2,4-diisopropylthioxanthone, ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3- Yl]-, 1- (0-acetyloxime), 1,2-octadion-1- [4- (phenylthio)-, 2- (O-benzoyloxime)] and the like, 2, 4,6-trichloro-s-triazine, 2-phenyl 4 6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) ) -S-triazine, 2-piperonyl-4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) -6-styryl-chloromethyl) -s-triazine, 2,4- Bis (trichloromethyl) -6-styryl-s-triazine, 2- (naphth-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxy-naphth-1-yl)- 4,6-bis (trichloromethyl) -s-triazine, 2,4-trichloromethyl (piperonyl) -6-triazine, and 2,4-trichloromethyl (4'-metho Use a triazine photopolymerization initiator such as cistyryl) -6-triazine, a borate photopolymerization initiator, a carbazole photopolymerization initiator, an imidazole photopolymerization initiator, or a mixture containing one or more thereof. be able to.

  Examples of the solvent include cyclohexane, cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, ethylbenzene, ethylene glycol diethyl ether, xylene, ethyl cellosolve, and methyl-n. Amyl ketone, propylene glycol monomethyl ether toluene, methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, petroleum solvents, or mixtures containing one or more thereof can be used.

  In addition, an additive may be added to the colorant-containing photosensitive composition as necessary. As the additive, for example, a surfactant, a storage stabilizer, or a mixture containing one or more thereof can be used.

  Examples of the surfactant include sodium lauryl sulfate, polyoxyethylene alkyl ether sulfate, sodium dodecylbenzene sulfonate, alkali salt of styrene-acrylic acid copolymer, sodium stearate, sodium alkyl naphthalene sulfonate, alkyl diphenyl ether disulfone. Sodium sulfate, monoethanolamine lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, and polyoxyethylene alkyl Anionic surfactants such as ether phosphates, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyester Nonionic surfactants such as oxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphate ester, polyoxyethylene sorbitan monostearate, and polyethylene glycol monolaurate, alkyl quaternary ammonium salts, and addition of ethylene oxide thereof A chaotic surfactant such as an alkyl, an alkylbetaine such as alkyldimethylaminoacetic acid betaine, and an amphoteric surfactant such as an alkylimidazoline, a silicon-based surfactant, or a mixture containing one or more thereof be able to.

  Examples of the storage stabilizer include quaternary ammonium chlorides such as benzyltrimethyl chloride and diethylhydroxyamine, organic acids such as lactic acid and oxalic acid, organic acids such as methyl ether, t-butylpyrocatechol, triethylphosphine and triphenylphosphine. Phosphine, phosphite, or a mixture containing one or more of them can be used.

  Next, the color filter for a solid-state image sensor according to this embodiment will be described in detail.

  FIG. 1 is a cross-sectional view schematically showing an example of the configuration of the solid-state imaging device according to the present embodiment. As shown in FIG. 1, the solid-state imaging device 1 is a two-dimensional image sensor such as a CCD image sensor or a CMOS image sensor, and includes a semiconductor chip 2, a first planarization layer 3, a color filter 4, Two planarizing layers 5 and a microlens array 6 are provided. The semiconductor chip 2 is provided with a plurality of photoelectric conversion elements 21.

  The color filter 4 is disposed on the first planarization layer 3 and includes a green coloring layer 4G, a blue coloring layer 4B (not shown), and a red coloring layer 4R. As shown in FIG. 2, the green coloring layer 4G, the blue coloring layer 4B, and the red coloring layer 4R constitute a Bayer array. The green colored layer 4G is composed of a plurality of green filter segments G forming a checkered array pattern in plan view. The blue colored layer 4B is composed of a plurality of blue filter segments B that are spaced apart from each other and form a square lattice-like arrangement pattern. The red colored layer 4R is composed of a plurality of red filter segments R that are spaced apart from each other and form a square lattice-like arrangement pattern.

  The filter segments G, B, and R are adjacent to each other in the in-plane direction, and a square arrangement is adopted here. These filter segments G, B, and R each face a pixel.

  The vertical and horizontal dimensions of the filter segments G, B, and R in plan view are, for example, in the range of about 0.8 μm to about 10 μm, and the colorant-containing photosensitive composition of the present embodiment is particularly about 0. It is used in the range of 9 μm to about 2.5 μm.

  The color filter 4 in the solid-state imaging device 1 configured as described above is manufactured by, for example, the following method.

  First, the first planarization layer 3 is formed on the semiconductor chip 2. Next, a green colored layer 4G is formed on the first planarizing layer 3. That is, the photosensitive composition containing the green colorant described above is applied on the planarizing layer 3 to form a coating film, and the solvent in the photosensitive composition is dried to some extent by pre-baking. Prior to pre-baking, the solvent may be dried by placing it in a vacuum state. Next, pattern exposure is performed using a photomask, and then the coating film is developed to remove the photosensitive composition in the unexposed areas. Further, baking is performed at a temperature of 200 degrees or higher. As a result, a green colored layer 4G having a checkered array pattern as shown in FIG. 1 is obtained. In addition, it is preferable that the shape of the green colored layer 4G in a plan view is a structure in which the four corners of the pixel are bridged at the connecting portion.

  Next, the blue colored layer 4B and the red colored layer 4R are formed on the first planarizing layer 3 by the same method as the green colored layer 4G. Thereby, the color filter 4 which concerns on this embodiment can be obtained. Note that either the blue colored layer 4B or the red colored layer 4R may be formed first.

  It is preferable to use an alkaline developer for development. As the alkaline developer, an inorganic alkali developer such as sodium hydroxide, potassium hydroxide or sodium carbonate, or an organic alkali developer such as tetrahydroxyammonium can be used. Moreover, in order to improve the wettability to a coating film, it is also preferable to include a surfactant in the developer.

  Here, the residue will be described. As described above, particles derived from the photosensitive composition present in the pixel pattern after the photosensitive composition has been removed in the unexposed areas after development are referred to as residues. The residue is quantified using a scanning electron microscope. One pixel pattern of the unexposed portion after development, that is, one pixel from which the photosensitive composition has been removed is photographed with a scanning electron microscope at a constant magnification to obtain an image. Using the difference in contrast between the residue and the substrate surface in the acquired image, the residue and the substrate surface are binarized, the area of the residue is calculated, and quantified as a ratio to the area in one pixel.

  The residue affects the color characteristics when the next colored layer is formed. Specifically, since the incident light is reflected and absorbed by the residue, the peak transmittance is lowered. When the incident light is weakened, the signal output of the sensor becomes weak and the sensor sensitivity decreases.

  In addition, if the transmitted light rate varies from pixel to pixel due to the presence of residues in the same color, variations in sensor sensitivity increase, resulting in color unevenness and poor color reproducibility. The finer the pixel size, the greater the effect of even a small decrease in transmittance, which causes a decrease in sensitivity and variation. In order not to change the spectral characteristics, the residue is desirably 5% or less.

  Further, the amount of the residue affects the solubility of the polymerizable monomer in the colorant-containing photosensitive composition in the alkaline developer.

  The colorant-containing photosensitive composition according to this embodiment is a state in which a pigment as a colorant is uniformly dispersed in a particle form of several tens of nm by a dispersant, and the pigment is adsorbed on a part of the dispersant. Yes. Dispersants and pigments are poorly soluble in an alkaline developer, and tend to remain on the substrate after the development process. In order to remove the dispersant and the pigment in the development process, by increasing the solubility of the colorant-containing photosensitive composition in the developer, the dispersant and the pigment adsorbed to the developer are developed together. By eluting into the liquid, it becomes possible to form a portion having no pattern. Since the dispersant adsorbed to the pigment is compatible with other polymers and polymerizable monomer components, it is necessary to increase the solubility of the polymerizable monomer components in the colorant-containing photosensitive composition in an alkaline developer. There is. If the colorant-containing photosensitive composition has low solubility in the developer, the pigment or dispersant remains on the substrate during development, resulting in a residue, which causes a decrease in sensitivity or variation when the solid-state imaging device is formed.

  According to the colorant-containing photosensitive coating composition according to this embodiment, the colorant-containing photosensitive composition contains an acrylic compound having 2 or less unsaturated bond groups in one molecule, and an unsaturated bond group. When the acrylic compound having 3 or more acrylic compounds in one molecule and having 2 or less unsaturated bond groups in one molecule contains 10% by mass to 30% by mass of the total amount of the photopolymerizable monomer, The residue present in the unexposed pixel pattern portion can be 5% or less of the area of the single pixel pattern, and the spectral characteristics can be stabilized. Therefore, it is possible to obtain a high-sensitivity and high-definition color filter for a solid-state image sensor that can suppress a decrease in sensitivity and variations in sensitivity when used in a solid-state image sensor.

  Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. In the examples, “parts” and “%” represent “parts by mass” and “mass%”, respectively. “PGMAC” means propylene glycol monomethyl ether acetate.

  In Examples and Comparative Examples, eight types of samples (Examples 1 to 3 and Comparative Examples 1 to 5) were prepared for the photosensitive green coloring composition for color filters used in typical solid-state imaging devices.

  First, acrylic varnish A used in Examples and Comparative Examples was synthesized to prepare a green pigment dispersion.

<Synthesis of acrylic varnish 1>
370 parts of propylene glycol monomethyl ether acetate is put into a reaction vessel, heated to 80 ° C. while injecting nitrogen gas into the vessel, 10 parts of cyclohexyl methacrylate, 40 parts of benzyl methacrylate and glycidyl methacrylate-acrylic at the same temperature. A mixture of 20 parts of the acid reactant and 30 parts of acrylic acid was added dropwise over 1 hour to carry out the polymerization reaction. After completion of the dropwise addition, the mixture was further reacted at 80 ° C. for 3 hours, and then 1.0 part of azobisisobutyronitrile dissolved in 50 parts of propylene glycol monomethyl ether acetate was added, and further reacted at 80 ° C. for 1 hour. Subsequently, an acrylic resin solution was obtained. The weight average molecular weight of the acrylic resin was about 10,000. After cooling to room temperature, about 2 g of resin solution was sampled and heated and dried at 180 ° C. for 20 minutes to measure the non-volatile content. Propylene glycol monomethyl ether so that the non-volatile content was 20% by weight in the previously synthesized resin solution. Acrylic varnish solution was prepared by adding acetate to obtain acrylic varnish 1.

<Preparation of green pigment dispersion>
A mixture having the following composition was uniformly stirred, dispersed with a sand mill for 5 hours using glass beads having a diameter of 1 mm, and then filtered with a 5 μm filter to prepare a green dispersion A.
Green pigment: C.I. I. Pigment Green 58 6.5 parts Yellow Pigment: C.I. I. Pigment Yellow 150 6.5 parts Dispersant: Disperbyk 2001 (manufactured by Big Chemie) 7.0 parts Acrylic varnish 1 (solid content 20%) 22.3 parts PGMAC 57.7 parts

Example 1
[Green Colorant Containing Photosensitive Composition 1]
A mixture having the composition shown below was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to obtain a photosensitive composition 1 containing green colorant.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 0.3 part by mass of M-140 (manufactured by Toagosei Co., Ltd., 1 unsaturated bond group, molecular weight: 249)
-Photopolymerizable monomer: 1.5 parts by mass of M-402 (manufactured by Toagosei Co., Ltd., 5-6 unsaturated bond groups, unsaturated bond equivalent: 96 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

Example 2
[Green Colorant-Containing Photosensitive Composition 2]
The mixture having the composition shown below was stirred and mixed so as to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 2.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 0.4 part by mass of M-215 (manufactured by Toagosei Co., Ltd., 2 unsaturated bond groups, molecular weight: 291)
-Photopolymerizable monomer: 1.4 parts by mass of DPCA30 (Nippon Kayaku Co., Ltd., 5-6 unsaturated bond groups, unsaturated bond equivalent: 154 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

Example 3
[Green Colorant-Containing Photosensitive Composition 3]
A mixture having the composition shown below was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 3.

-52.0 parts by mass of the above green dispersion A-0.2 parts by mass of photopolymerizable monomer: M-215 (manufactured by Toagosei Co., Ltd., 2 unsaturated bond groups, molecular weight: 291)
Photopolymerizable monomer: 1.6 parts by mass of M-309 (manufactured by Nippon Kayaku Co., Ltd., 3 unsaturated bond groups, unsaturated bond equivalent: 109 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<< Comparative Example 1 >>
[Green Colorant Containing Photosensitive Composition 4]
A mixture having the composition shown below was stirred and mixed so as to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 4.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 0.9 part by mass of M-215 (manufactured by Toagosei Co., Ltd., 2 unsaturated bond groups, molecular weight: 291)
Photopolymerizable monomer: 0.9 part by mass of M-420 (manufactured by Toagosei Co., Ltd., 5-6 unsaturated bond groups, unsaturated bond equivalent: 96 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<< Comparative Example 2 >>
[Green Colorant Containing Photosensitive Composition 5]
A mixture having the composition shown below was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 5.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 0.3 part by mass of M-208 (manufactured by Toagosei Co., Ltd., 2 unsaturated bond groups, molecular weight: 420)
Photopolymerizable monomer: 1.5 parts by mass of M-420 (manufactured by Toagosei Co., Ltd., 5-6 unsaturated bond groups, unsaturated bond equivalent: 96 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<< Comparative Example 3 >>
[Green Colorant-Containing Photosensitive Composition 6]
A mixture having the composition shown below was stirred and mixed so as to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 6.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 0.2 part by mass of M-140 (manufactured by Toagosei Co., Ltd., 1 unsaturated bond group, molecular weight: 249)
Photopolymerizable monomer: 1.6 parts by mass of M-321 (manufactured by Toagosei Co., Ltd., 3 unsaturated bond groups, unsaturated bond equivalent: 232 g / equivalent)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<< Comparative Example 4 >>
[Green Colorant-Containing Photosensitive Composition 7]
A mixture having the composition shown below was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 7.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 1.8 parts by mass of M-215 (manufactured by Toagosei Co., Ltd., 2 unsaturated bond groups, molecular weight: 291)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<< Comparative Example 5 >>
[Green Colorant-Containing Photosensitive Composition 8]
A mixture having the composition shown below was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to obtain a green colorant-containing photosensitive composition 8.

-Green dispersion A 52.0 parts by mass-Photopolymerizable monomer: 1.8 parts by mass of M-402 (5 to 6 unsaturated bond groups, molecular weight: 96, manufactured by Toagosei Co., Ltd.)
Acrylic varnish 1 (solid content 20%) 0.9 parts by mass Photopolymerization initiator: OXE-02 (BASF Japan Ltd.) 0.5 parts by mass PGMAC 44.7 parts by mass

<Evaluation of coloring composition>
About the above colored composition, exposure sensitivity, pattern line width uniformity, pattern film thickness uniformity, and residue evaluation were performed by the following methods.

[Pattern formation]
On a 6-inch silicon wafer, a planarizing film resist solution (HL-18s: manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) was applied by a spin coating method, and heat-treated on a hot plate at 100 ° C. for 6 minutes as a prebake. Furthermore, it processed in 230 degreeC oven for 1 hour, the coating film was hardened, and the planarizing film with a film thickness of 1.0 micrometer was formed.

  The green photosensitive coloring composition was applied on the silicon wafer with the planarizing film thus obtained by a spin coater, and pre-baked and heat-treated for 1 minute on a 100 ° C. hot plate. The film thickness after pre-baking was adjusted to 0.8 μm.

  Next, using an i-line stepper (FPA-5510iZ manufactured by Canon Inc.), exposure was performed with a focal length of −0.6 μm through a mask having a square pixel pattern of 1.1 μm square. The exposure amount was 5,000 J.

  The exposed coating film was developed with an organic alkali developer (OD210 manufactured by ADEKA Corporation) for 1 minute, washed with paddle water for 1 minute, spin-dried, and the substrate was dried. After developing and washing with water, a green colored pattern was obtained. The obtained green coloring pattern was heat-treated for 4 minutes on a hot plate at 230 ° C. The thickness of the green colored pattern after the heat treatment was 0.71 μm. The film thickness was measured with an AFM (Atomic Force Microscope) manufactured by Toyo Technica (i-nano).

[Exposure sensitivity]
Using an i-line stepper (FPA-5510iZ manufactured by Canon Inc.) and a mask with a 1.1 μm square pixel pattern, the focal length is −0.6 μm, and the exposure amount is in the range of 1,000 J to 12,000 J. When the appropriate sensitivity is less than 5,000 J, the exposure amount at which the bottom line width becomes 1.1 μm after exposure, irradiation, development at 1,000 J intervals or 100 J intervals, development, and baking for 4 minutes at 230 ° C. , When it is 5,000 J or more and less than 9,000 J, Δ, and when it is 9,000 J or more, x.

[Uniform pattern line width]
Using an i-line stepper (FPA-5510iZ manufactured by Canon Inc.) and a mask with a square pixel pattern of 1.1 μm square, the focal length is −0.6 μm, and the exposure amount is in the range of 1,000 J to 10,000 J. , 0.20 when the amount of change with respect to the exposure amount of the bottom bottom line width after exposure exposure at 1,000 J intervals, development, and baking at 230 ° C. for 4 minutes is 0.20 μm or less.
When it was larger than μm and not larger than 0.25 μm, it was Δ, and when it was larger than 0.25 μm, it was marked as x.

[Pattern thickness uniformity]
There is a step at the end of one chip of the solid-state imaging device. Due to such a step, the film thickness may increase at the end of one chip. Therefore, for the film thickness uniformity, the film thickness change was measured at a pixel in which the step at the end of one chip was omitted. The case where the measured change amount of the film thickness was 0.05 μm or less was rated as “◯”, the case where it was larger than 0.05 μm and 0.07 μm or less was Δ, and the case where it was larger than 0.07 μm was marked as “X”.

[Residue evaluation]
The pixel pattern portion from which the colorant-containing photosensitive composition was removed after development was observed with a scanning electron microscope (s-4800, manufactured by Hitachi High-Technology Co., Ltd.) at a magnification of 30,000, and an image was taken. The area was calculated by binarizing the particulate residue in the photographed image, and the ratio of the total area of the residue to the area of one pixel pattern was calculated. The case where the ratio of the total area of the residue was smaller than 5% was marked as ◯, and the case where it was 5% or more was marked as x.

The evaluation results of the above characteristics are shown in Table 1 below.

  As shown in Table 1, an acrylic compound having 2 or less unsaturated bond groups in one molecule and an acrylic compound having 3 or more unsaturated bond groups in one molecule are contained. The colorant-containing photosensitive compositions 1 to 3 of Examples 1 to 3 containing 10% by mass or more and 30% by mass or less of the total amount of the photopolymerizable monomer in the acrylic compound having 2 or less in the molecule are the exposure sensitivity, the line The results show satisfactory results in all the characteristics of width uniformity, film thickness uniformity and residue evaluation. Therefore, it can be said that the colorant-containing photosensitive compositions 1 to 3 of Examples 1 to 3 can be applied to high-definition solid-state imaging devices.

  On the other hand, the coloring material containing photosensitive composition 4 of the comparative example 1 which the acrylic compound which has 2 or less of unsaturated bond groups in 1 molecule contains more than 50 mass% and 30% of photopolymerizable monomer whole quantity is The line width uniformity and residue evaluation are excellent, but the exposure sensitivity and film thickness uniformity are inferior.

  The colorant-containing photosensitive composition 5 of Comparative Example 2 in which the molecular weight of the acrylic compound having 2 or less unsaturated bond groups in one molecule is greater than 420 and 400 has exposure sensitivity, line width uniformity, and film thickness uniformity. Although the property is excellent, the residue evaluation is inferior.

  The colorant-containing photosensitive composition 6 of Comparative Example 3, which has an unsaturated bond equivalent of 232 g / equivalent and 200 g / equivalent of an acrylic compound having 3 or more unsaturated bond groups in one molecule, has line width uniformity and residue Although it is excellent in evaluation, exposure sensitivity and film thickness uniformity are inferior.

  The colorant-containing photosensitive composition 7 of Comparative Example 4 consisting only of an acrylic compound having 2 or less unsaturated bond groups in one molecule is weak in photocurability and is applied in the development process even when irradiated with 100,000 J. The film was completely dissolved, and no pattern remained on the substrate.

The colorant-containing photosensitive composition 8 of Comparative Example 5 consisting only of an acrylic compound having three or more unsaturated bonding groups in one molecule is excellent in exposure sensitivity and film thickness uniformity, but is uniform in line width. And residue evaluation is inferior.

<Preparation of blue coloring composition>
[Blue coloring composition 1]
A mixture of the following composition was uniformly stirred and mixed, then dispersed with a sand mill for 5 hours using glass beads having a diameter of 1 mm, and then filtered with a 5 μm filter to prepare a blue pigment dispersion 1.

Blue pigment: C.I. I. Pigment Blue 15: 6 12.0 parts by mass (“Rionol Blue ES” manufactured by Toyo Ink Manufacturing Co., Ltd.)
・ Dispersant 1.0 part by mass (“Solsperse 20000” manufactured by Zeneca)
Acrylic varnish A (solid content 20%) 35.0 parts by mass PGMAC 52.0 parts by mass Then, the mixture having the following composition was stirred and mixed to be uniform, and then filtered through a 0.45 μm filter to give a blue color. Composition 1 was obtained.

Blue colored dispersion 1 63.8 parts by mass Photopolymerizable monomer (unsaturated bond group number: 3) 1.3 parts by mass (M-325, molecular weight: 537, manufactured by Toagosei Co., Ltd.)
-Photopolymerizable monomer (unsaturated bond group number: 5-6) 1.3 parts by mass (M-402, manufactured by Toagosei Co., Ltd.)
Acrylic varnish A (solid content 20%) 2.8 parts by mass Photopolymerization initiator 1.1 parts by mass (Ciba Specialty Chemicals “OXE-01”: oxime ester initiator)
・ PGMAC 29.8 parts by mass

<Preparation of red coloring composition>
[Red coloring composition 1]
A mixture having the following composition was stirred and mixed uniformly, then dispersed with a sand mill for 5 hours using glass beads having a diameter of 1 mm, and then filtered with a 5 μm filter to prepare a red pigment dispersion 1.

-Red pigment: C.I. I. Pigment Red 254 10.0 parts by mass (“Rionol Blue ES” manufactured by Toyo Ink Manufacturing Co., Ltd.)
-Red pigment: C.I. I. Pigment Red 177 2.0 parts by mass (“Chromophthal Red A2B” manufactured by Ciba Specialty Chemicals)
・ Dispersant 1.0 part by mass (“Ajisper PB821” manufactured by Ajinomoto Fine Techno Co., Ltd.)
Acrylic varnish (solid content 20%) 35.0 parts by mass Propylene glycol monomethyl ether acetate (PGMAC) 52.0 parts by mass Then, a mixture of the following composition is stirred and mixed so as to be uniform, and then a 0.45 μm filter. To obtain a red colored composition 1.

-Red colored dispersion 1 63.8 parts by mass-Photopolymerizable monomer (number of unsaturated bond groups: 3) 1.9 parts by mass (M-325, molecular weight: 537, manufactured by Toagosei Co., Ltd.)
Photopolymerizable monomer (unsaturated bond group number: 5 to 6) 0.6 part by mass (M-402, manufactured by Toagosei Co., Ltd.)
Acrylic varnish A (solid content 20%) 2.8 parts by mass Photopolymerization initiator 1.1 parts by mass (Ciba Specialty Chemicals “OXE-01”: oxime ester initiator)
・ PGMAC 29.8 parts by mass

<Manufacture of color filters for solid-state imaging devices>
[Color filter 1 for solid-state image sensor]
On a 6-inch silicon wafer, a planarization film resist solution (HL-18s: manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) was applied by spin coating, and heat-treated for 6 minutes on a hot plate at 100 ° C. as a prebake. Furthermore, it processed in 230 degreeC oven for 1 hour, the coating film was hardened, the 1.0 micrometer planarizing film was formed, and the wafer with a planarizing film was obtained.

  The green coloring composition 1 was applied onto a silicon wafer with a flattening film by a spin coater, and pre-baked and heat-treated with a hot plate at 100 ° C. for 1 minute. The film thickness after pre-baking was adjusted to 0.8 μm.

  Next, using an i-line stepper (FPA-5510iZ manufactured by Canon Inc.), irradiation was performed at an exposure amount of 4,000 J through a 1.1 μm square pixel pattern mask with a focal length of −0.6 μm.

  The exposed coating film was developed with an organic alkali developer (OD210 manufactured by ADEKA Corporation) for 1 minute, washed with paddle water for 1 minute, spin-dried, and the substrate was dried. After development and washing with water, a green colored pattern was obtained. The obtained green coloring pattern was heat-treated with a hot plate at 230 ° C. for 1 hour. The film thickness of the green pattern after the heat treatment was 0.71 μm. The line width of the green pattern was 1.13 μm. The amount of change in film thickness in the substrate was 0.04 μm. The film thickness was measured with an AFM (Atomic Force Microscope) manufactured by Toyo Corporation (i-nano).

  The blue coloring pattern and the red coloring pattern were also formed in the same manner as the green coloring pattern except for the exposure amount to obtain a color filter. The amount of exposure was set to 8,000 J for the blue coloring pattern and 4,000 J for the red wearing pattern. The formed blue colored pattern had a thickness of 0.72 μm, and the red colored pattern had a thickness of 0.73 μm.

  A planarizing layer was provided on the color filter formed as described above. The planarization layer was formed, for example, by applying a planarization film resist solution (HL-18s: manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). A transparent resin layer was formed on the planarizing layer using, for example, an acrylic resin coating solution. Next, on the transparent resin layer, for example, a lens matrix material made of, for example, phenol resin having alkali solubility, photosensitivity, and heat flow was applied.

  Next, using a known photolithography process, the lens matrix material was patterned so as to leave a region serving as the lens matrix. The remaining lens matrix material was heat-treated and thermally reflowed, and transformed into a hemispherical shape to form a lens matrix. By setting the reflow amount to an appropriate amount of about 0.1 μm on one side, a smooth hemisphere having a gap between the unit lens molds of, for example, about 0.24 μm could be achieved.

Thereafter, a transfer process of the shape of the lens matrix was performed on the transparent resin layer by dry etching using a mixed gas of CF ₄ and C ₄ F _{8 with} the lens matrix as a mask to form a microlens. If the lens matrix and the transparent resin layer are uniformly etched from above, the etching proceeds downward while maintaining the shape of the lens matrix, so the transparent resin layer is etched to the same shape as the lens matrix. Can do. The microlens can be formed to have a height of 1 μm and a gap between unit lenses of 0.04 μm.

  Thus, the color filter for solid-state image sensors prepared using the green colorant-containing photosensitive compositions 1 to 3 of Examples 1 to 3 has a good pattern shape, no residue, and stable spectral characteristics. It was a thing. As a result, the solid-state imaging device including the obtained color filters can suppress the decrease in sensitivity and the variation in sensitivity more than ever.

  The colorant-containing photosensitive composition according to the present invention and a color filter using the same can be used for a solid-state imaging device including a solid-state imaging device such as a CCD or a CMOS.

1: Solid-state imaging device 2: Semiconductor chip 3: First flattening layer 4: Color filter 4G: Green filter 4R: Red filter 5: Second flattening layer 6: Microlens array 21: Photoelectric conversion device

Claims (3)

A colorant-containing photosensitive composition used for a color filter of a solid-state imaging device, comprising at least a colorant, a dispersant, a polymer, a photopolymerization initiator, a photopolymerizable monomer, and a solvent,
The photopolymerizable monomer contains an acrylic compound having 2 or less unsaturated bond groups in one molecule, and an acrylic compound having 3 or more unsaturated bond groups in one molecule,
Containing 10% by mass or more and 30% by mass or less of the total amount of the photopolymerizable monomer of an acrylic compound having 2 or less unsaturated bond groups in one molecule;
The molecular weight of the acrylic compound having 2 or less unsaturated bond groups in one molecule is 200 or more and 400 or less,
The coloring material containing photosensitive composition characterized by the unsaturated bond equivalent of 80 or more and 200 or less of the acrylic compound which has 3 or more of said unsaturated bond groups in 1 molecule.   A color filter comprising a colored layer comprising a cured film of the colorant-containing photosensitive composition according to claim 1.   A solid-state imaging device comprising the color filter according to claim 2.