JP2010085702A - Method of manufacturing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a color filter which improves rectangularity of each color pixel of the color filter and prevents exfoliation of blue pixels. <P>SOLUTION: Striped-shaped blue patterns 27B are formed on a support member 11 by using a dry etching method. Stripe-shaped red patterns 27R are formed on the support member 11 by using a photolithography method so as to fill gaps between blue patterns 27B. Respective color patterns 27B and 27R are dry-etched to form blue pixels 20B, red pixels 20R, and green pixel formation regions 39. Green pixels 20G are formed on the green pixel formation regions 39 by using a photolithography method. Rectangularity of each color pixel is improved because of the reduction of steps of forming isolated patterns. A blue layer 33B is formed as the first color and the blue layer 33B is dry-etched to form blue pixels 20B, thereby exfoliation of the blue pixels 20B is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color filter provided in a solid-state imaging device or the like.

  The solid-state imaging device is provided with a color filter in which colored pixels of a plurality of colors of red pixels, green pixels, and blue pixels are two-dimensionally arranged on a support such as a semiconductor substrate. In recent years, the increase in the number of pixels of a solid-state imaging device has been remarkable, and the pixel size has been significantly reduced when compared with a conventional solid-state imaging device having the same inch size. Also, as the pixel size decreases, the performance requirements for color separation become stricter. To maintain device characteristics such as color shading characteristics and color mixing prevention, the performance required for color filters is reduced to thinner, rectangular, and between each colored pixel. Further, there is a demand for performance such as eliminating an overlap region where colors overlap.

  As a method for producing such a color filter, a photolithographic method has been widely used. In the photolithography method, a colored photosensitive composition is applied and dried on a support to form a colored layer, and then the colored layer is subjected to pattern exposure, development, and baking to form a colored pixel of the first color (for example, green). In the same manner, the remaining colored pixels are formed. The photolithographic method can reduce initial investment because the manufacturing process conforms to the photolithographic process of semiconductor manufacturing. In addition, the photolithographic process can be used to manufacture color filters with high-precision exposure and overlay accuracy. Widely used as a preferred method.

  By the way, as shown in FIG. 32A, in the color filter 2 formed by the photolithography method, colored pixels are formed in areas where the corners of the colored pixels (red pixel 3, green pixel 4, and blue pixel 5) are gathered. As a result, a blank region 6 in which no is formed is formed. Moreover, as shown to (B), the dent 7 where the film thickness of each coloring pixel becomes thin will arise in the vicinity of the boundary between each coloring pixels 3-5. This is because each of the colored pixels 3 to 5 is as designed because the mask bias applied to the photomask for pattern exposure is not optimized and the curing efficiency of the colored photosensitive composition with respect to the exposure light source is low. It is because it is not formed with the dimension and shape.

  As countermeasures against such problems, studies such as optimization of mask bias and the like and improvement of curing efficiency of the colored photosensitive composition with respect to an exposure light source have been limited. Therefore, after forming colored pixels (red pixels, blue pixels) for the second and subsequent colors in the region surrounded by the green pixels formed in a checkered pattern, a thermal reflow process is performed to perform the second and subsequent colored pixels. A technique is known that suppresses the generation of the blank area 6 and the dent 7 described above by heat-flowing the colored pixels and filling the area with colored pixels for the second and subsequent colors (see Patent Document 1).

  However, Patent Document 1 is a technology that is easily influenced by the performance and process conditions of the colored photosensitive composition used for forming the colored pixels for the second and subsequent colors. For example, the colored pixels are likely to be filled in a region having a high temperature. On the other hand, there is a problem that the heating distribution of the support is reflected in the embedding property as it is, for example, the coloring is difficult to be buried in the region where the temperature is low.

  In addition, when forming a color filter using a photolithographic method, a high-resolution technique of less than 2.0 μm size is required to cope with the recent miniaturization and high definition of solid-state imaging devices. The photolithographic method is reaching the limit of pattern formation in terms of resolution. For this reason, the above-mentioned problem (occurrence of blank area 6 and dent 7) of the photolithographic method becomes more and more remarkable.

  In addition, a technique using a dye has been proposed as a technique for dealing with miniaturization and high definition of a solid-state imaging device by a photolithography method. However, curable compositions containing dyes are generally inferior to pigments in terms of light resistance, thinning, and ease of changing transmission spectral characteristics, for example. In particular, in the case of the use for producing a color filter for a solid-state imaging device, a film thickness of 1.0 μm or less is required, so that a large amount of dye must be added to the curable composition. There are various problems such as insufficient pattern formation, remarkably difficult pattern formation, and the like.

  Incidentally, a dry etching method is known as a method that is thinner and more effective for forming a fine pattern than a photolithography method. The dry etching method has been conventionally employed as a method for forming a pattern (each colored pixel) in a rectangular shape, and a pattern forming method in which a photolithographic method and a dry etching method are combined has been proposed (for example, Patent Document 2, 3).

In Patent Documents 2 and 3, a colored layer of the first color is formed on a support, and the colored layer of the first color is patterned by a dry etching method (resist mask formation, dry etching). A technique is described in which after the colored pixels are formed, the second and subsequent colored pixels are sequentially formed by a photolithography method. In Patent Document 2, the colored layer of the first color is formed by a coating film made of a colored thermosetting composition, and in Patent Document 3, the colored layer of the first color is formed by a vapor deposition method.
JP 2006-292842 A JP 2001-249218 A JP 2006-339376 A

  However, in Patent Document 2 and Patent Document 3, the colored pixels of the first color can be formed in a rectangular shape, but the colored pixels of the second color and the third color are formed by the photolithography method. Legal issues arise. Furthermore, the colored layer of the first color formed by vapor deposition of Patent Document 3 can be easily thinned, but it is difficult to ensure solvent resistance. For this reason, when peeling the mask (photoresist) for dry etching, there is a possibility that the color may come off due to the peeling solvent.

  In the conventional color filter manufacturing method including Patent Document 2 and Patent Document 3, there is a limit (lower limit) in the size of the pattern (each colored pixel) that can be formed, and further, the pattern formability and the color pixel (colored layer) It is difficult to ensure reliability.

  Further, in Patent Documents 2 and 3, after the colored layers of the first color to the third color are formed on the support, each colored layer is patterned to form each colored pixel, that is, a plurality of isolated patterns (island patterns). Direct formation. Such a plurality of isolated patterns include a rectangular shape of the cross-sectional shape in the width direction of the pattern (hereinafter simply referred to as a pattern or a rectangular shape of a colored pixel), an angle of the isolated pattern when the isolated pattern is observed from the upper surface (hereinafter simply referred to as a simple pattern). It is difficult to suppress roundness of corners of isolated patterns). This is because, in the formation of an isolated pattern by the photolithography method, it is difficult to sufficiently increase the edge contrast of the pattern (exposure image) formed on the colored layer at the time of exposure. This is because of the occurrence of symptoms. In addition, since the rectangular shape of the cross section is affected by the pattern polymerizability (photopolymerizability of the colored layer) and developability, it is difficult to form the cross section at an acute angle as long as the photolithography method is used.

  Furthermore, when forming an isolated pattern by the photolithography method, the colored photosensitive composition particularly used for the color filter material is because the rectangularity of the pattern is inferior to that of a general photoresist. In addition, when an isolated pattern is formed by a dry etching method, a resist pattern (mask) for dry etching is formed by a photolithography method. The degree of corner roundness is better suppressed than when a colored layer is formed by photolithography. However, it is difficult to completely suppress the rounded corners of the isolated pattern due to the proximity effect during exposure.

  Furthermore, in Patent Documents 2 and 3, when a blue pixel having a blue pigment (particularly a blue pigment) is exposed and developed by a photolithography method as a colored pixel for the second and subsequent colors, a blue pixel is formed. It is difficult to ensure the adhesion of the resin and there is a risk of peeling. This is because the exposure light (365 nm in this case) has a large absorption coefficient by the colored layer, so that it is difficult for the exposure light to reach the substrate, and when the colored layer is not sufficiently photopolymerized, This is because it dissolves in the developer.

  The present invention has been made to solve the above problem, and further improves the rectangularity of the colored pixels while improving the formation limit of the pattern (each colored pixel) and making the pattern finer and thinner, and An object of the present invention is to provide a method for manufacturing a color filter capable of ensuring the adhesion of blue pixels.

  In order to achieve the above object, a method for producing a color filter according to the present invention includes a color filter production method for producing a color filter in which a plurality of colored pixels are two-dimensionally arranged on a support. A first color pattern forming step of forming a first color pattern of a first color stripe including at least a blue pigment, and a second color so as to fill a gap between the first color patterns on the support. A second color pattern forming step of forming a stripe-shaped second color pattern, patterning the first color pattern and the second color pattern by a dry etching method, and forming a first color pixel on the support; A patterning step of forming a second color pixel and a third color pixel formation region for forming the third color pixel, and forming the third color pixel in the third color pixel formation region And having a third color pixel forming process of.

  The first color pattern preferably includes a violet dye. Thereby, even when the first color pattern / pixel, that is, the blue pattern / pixel is formed of a thin film, the spectral characteristics can be improved.

  In the first color pattern forming step, a first color layer forming step of forming a first color layer comprising a colored thermosetting composition of the first color on the support, and the first color layer Further, a first resist pattern forming step of forming a first resist pattern corresponding to the first color pattern using a photoresist, and dry etching the first color colored layer using the first resist pattern as a mask. And a first dry etching step for forming the first color pattern.

  In the second color pattern forming step, a second color layer forming step of forming a second color layer made of a colored photocurable composition of the second color on the support on which the first color pattern is formed. And a second color layer exposure / development step of forming the second color pattern by pattern exposure / development of the second color layer.

  In the second color pattern forming step, a second color layer forming step of forming a second color layer made of a colored thermosetting composition of the second color on the support on which the first color pattern is formed. A second resist pattern forming step of forming a second resist pattern corresponding to the second color pattern using a photoresist on the second color coloring layer, and using the second resist pattern as a mask, It is preferable to include a second dry etching step in which the two-color coloring layer is dry-etched to form the second color pattern.

  In the second color pattern forming step, a second color layer forming step of forming a second color layer made of a colored thermosetting composition of the second color on the support on which the first color pattern is formed. And a surface of the second color colored layer is planarized until the second color colored layer is removed from the first color pattern to form the second color pattern. And a planarization treatment step.

  The third color pattern forming step comprises a colored photocurable composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel formation region are formed. A third color layer forming step for forming a third color layer; and a third color layer exposure / development step for pattern exposure / development of the third color layer to form the third color pixel. It is preferable.

  The third color pixel forming step comprises a colored thermosetting composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel formation region are formed. A third color layer forming step for forming a third color layer, and a third resist pattern forming step for forming a third resist pattern corresponding to the third color pixel formation region on the third color layer. The third color pattern is preferably dry-etched using the third resist pattern as a mask to form the third color pixel.

  The third color pixel forming step comprises a colored thermosetting composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel formation region are formed. A third color layer formation step for forming a third color layer, and a surface of the third color layer until the third color layer is removed from the first color pixel and the second color pixel. It is preferable to have a third color layer flattening process for forming a third color pixel by performing a flattening process.

  The planarization process is preferably performed by at least one of an etch back process and a polishing process.

  When the planarization process is performed by the polishing process, it is preferable to perform a water washing process for washing the surface to be polished after the polishing process, and a dehydration process process for performing a dehydration process on the surface to be polished after the water washing process.

  Before the first resist pattern forming step, there is a stopper layer forming step for forming a transparent flattening stopper layer on the first colored layer, and the first resist pattern forming step includes the first resist pattern forming step. It is preferable that a pattern is formed on the stopper layer, and the first dry etching step uses the first resist pattern to dry-etch the stopper layer in a stripe shape corresponding to the first color pattern.

  In the second color coloring layer flattening treatment step, it is preferable that the surface of the second color coloring layer is flattened until the stopper layer is exposed.

  In the third color layer flattening process, it is preferable that the surface of the third color layer is flattened until the stopper layer is exposed.

  It is preferable that the first color pattern and the second color pattern are formed such that adjacent patterns touch each other on the surface.

  The color filter of the present invention is manufactured by the color filter manufacturing method according to any one of claims 1 to 15.

  The color filter and the manufacturing method thereof according to the present invention include a step of forming a stripe-shaped first color pattern containing a blue pigment on a support, and a stripe so as to fill a gap between the first color patterns. Forming a second color pattern, forming a region for forming a third color pixel, and forming a third color pixel in this region, so that an isolated pattern can be formed. It is possible to reduce the number of steps to be performed. As a result, when the stripe pattern is formed by the photolithography method, the contrast of the edge of the pattern formed on the exposed surface is higher than when the isolated pattern is formed. Can be suppressed, and the rectangularity of each colored pixel can be improved. Also, when the stripe pattern is formed by the dry etching method, the rectangularity is further improved for the same reason, so that the rectangularity of each colored pixel can be improved. Furthermore, as a first color pixel (first color pattern), when a blue pixel pattern is formed by a dry etching method, when the photopolymerization by the photolithography method is not sufficient, the blue layer in the vicinity of the substrate is not developed. Factors that dissolve in the developer can be eliminated. As a result, the blue pixel adhesion can be ensured.

  As shown in FIG. 1, the solid-state imaging element 10 includes a light receiving element (photodiode) 12 provided on a support 11, a color filter 13, a planarizing film 14, a microlens 15, and the like. Note that, in FIG. 1 (the same applies to other drawings), in order to clarify each part, the ratio of the thickness and the width is disregarded and a part is exaggerated.

  The support 11 is not particularly limited as long as it is used for a color filter. For example, soda glass, borosilicate glass, quartz glass, and the like in which a transparent conductive film is attached to these used in a liquid crystal display element or the like. In addition, a photoelectric conversion element substrate used for a solid-state imaging element or the like, for example, a silicon substrate, an oxide film, silicon nitride or the like can be given. Further, an intermediate layer or the like may be provided between the support 11 and the color filter 13 as long as the present invention is not impaired.

  On the surface layer of the support 11, the light receiving elements 12 are arranged in a two-dimensional matrix (square lattice). In addition, although not shown in the figure, a well-known read gate, vertical transfer path, horizontal transfer path, output amplifier, and the like are provided between the light receiving elements 12 on the surface layer.

  The surface of the support 11 is covered with a light-transmitting insulating film (not shown), and a transfer electrode 17 is formed on the insulating film so as to cover the read gate, the vertical transfer path, and the like. . By controlling the voltage applied to the transfer electrode 17, the charge accumulated in the light receiving element 12 is vertically transferred through the read gate through the vertical transfer path. Further, a light shielding film 18 is formed on the surface of the support 11 so as to cover the transfer electrode 17 and to open at a position immediately above the light receiving element 12. A transparent device protective film 19 is formed on the light shielding film 18 to cover the entire surface and the opening. A color filter 13 is formed on the protective film 19.

  The color filter 13 is formed on the protective film 19. In the following description, a colored film (so-called solid film) formed on the support 11 without dividing the region is referred to as a “colored (red, green, blue) layer”, and the region is divided into patterns. The formed colored film (for example, a film patterned in a stripe shape) is referred to as a “colored (red, green, blue) pattern”. In addition, among the colored patterns, a colored pattern (for example, a colored pattern patterned into a square) that is an element constituting the color filter 13 is referred to as a “colored (red, green, blue) pixel”.

  Here, as a form in which regions are divided into patterns (forms to be patterned), a resist pattern is formed on a colored layer in addition to a form in which a photosensitive colored film is patterned by exposure and development. A pattern in which a colored layer is patterned by etching using this resist pattern as an etching mask, a colored layer is formed so as to be embedded in a patterned recess provided on the support 11, and the colored layer is formed The form etc. which are patterned by removing the part which protruded from the recessed part are included.

  3A and 3B, (A) is a top view, (B) is a sectional view taken along line X1-X2 in (A), and (C) is a sectional view taken along line Y1-Y2 in (A). It is.

  Further, in (A) of each figure, “R” indicates any one of a red layer, a red pattern, and a red pixel, “B” indicates any one of a blue layer, a blue pattern, and a blue pixel, and “G”. Indicates either a green layer or a green pixel, and “F” indicates either a resist pattern (photoresist). “R + B” indicates that “B” is stacked on “R”, “R + B + G” indicates that “B” and “G” are stacked on “R”, and “B + G” indicates that “G” is laminated on “B”.

  The color filter 13 includes a plurality of two-dimensionally arranged red pixels (second color pixels) 20R, green pixels (third color pixels) 20G, and blue pixels (first color pixels) 20B. Each of the colored pixels 20R, 20G, and 20B is formed above the light receiving element 12. The green pixels 20G are formed in a checkered pattern, and the blue pixels 20B and the red pixels 20R are formed between the green pixels 20G (see FIGS. 13A and 32). In FIG. 1, in order to explain that the color filter 13 is composed of pixels of three colors, the colored pixels 20R, 20G, and 20B are displayed in a line, but in actuality, FIG. As shown in (B) and (C).

  The planarization film 14 is formed so as to cover the upper surface of the color filter 13 and has a flat upper surface. The microlens 15 is a lens provided with a convex surface upward, and is provided above the planarizing film 14 and above each light receiving element 12. Each microlens 15 efficiently guides light from the subject to each light receiving element 12.

[Color filter manufacturing process]
Next, the color filter manufacturing process 22 for forming the color filter 13 will be described with reference to FIG. The color filter manufacturing process 22 is roughly divided into a blue pattern forming process 23, a red pattern forming process 24, and a green pixel forming process 25.

  In the blue pattern forming step 23, a striped blue pattern (first color pattern) 27 </ b> B is formed on the surface of the support 11. The blue pattern forming step 23 includes a blue layer forming step 28, a resist pattern forming step 29, a dry etching step 30, and a photoresist removing step 31.

  In the blue layer forming step 28, a blue layer 33B (first colored layer, see FIG. 3) is formed on the support 11 using a thermosetting composition (blue thermosetting composition) containing at least a blue pigment. To do. In the resist pattern forming step 29, a striped resist pattern 34 (first resist pattern, see FIG. 4) is formed on the blue layer 33B using a photoresist. The resist pattern 34 has an opening 34a (see FIG. 4) corresponding to the blue pattern 27B.

  In the dry etching step 30, the blue pattern 33B is formed by dry etching (patterning) the blue layer 33B using the resist pattern 34 as a mask. In the photoresist removing step 31, the resist pattern 34 is removed from the blue pattern 27B.

  In the red pattern forming step 24, the support 11 is striped using a red photocurable composition containing a red pigment so as to fill the gaps between the blue patterns 27B (regions where the blue pattern 27B is not formed). The red pattern 27R (second color pattern, see FIG. 8) is formed. The red pattern forming step 24 includes a red layer forming step 35 and an exposure / developing step 36.

  In the red layer forming step 35, a red layer 33R (second colored layer, see FIG. 7) is formed using a red photocurable composition so as to cover the surface of the support 11 on which the blue pattern 27B is formed. . The red layer 33R is formed so as to embed regions between the patterns of the blue pattern 27B (regions sandwiched between the patterns) while covering the blue pattern 27B. In the exposure / development process 36, the red layer 33R is exposed and developed to form a red pattern 27R.

  The green pixel forming step 25 is roughly composed of a green pixel region forming step 25a, a green layer forming step 37, and an exposure / development step 38. In the green pixel region forming step 25a, a green pixel forming region 39 (see FIG. 10A) for forming a green pixel (pattern) 20G is formed on the surface of the support 11, that is, the green pixel forming region 39. This is a removal step of removing the blue pattern 27B and the red pattern 27R.

  The green pixel region forming process 25a includes a resist pattern forming process 40, a dry etching process 41, and a photoresist removing process 42. In the resist pattern forming step 40, a resist pattern 43 (third resist pattern, see FIG. 9) is formed on the blue and red patterns 27B and 27R using a photoresist. The resist pattern 43 has an opening 43a (see FIG. 9) corresponding to the green pixel formation region 39, and the regions corresponding to the green pixel formation region 39 of both patterns 27B and 27R are exposed, and the rest Protect the area.

  In the dry etching step 41, the blue and red patterns 27 </ b> B and 27 </ b> R are patterned by a dry etching method using the resist pattern 43 as a mask to form a green pixel formation region 39 on the support 11. The green pixel formation region 39 is formed in a checkered pattern according to the arrangement pattern of the green pixels 20G (a pattern corresponding to the arrangement pattern when the arrangement pattern of the green pixels 20G is not a checkered pattern).

  Further, when the dry etching process 41 is executed, the blue pixel 20 </ b> B and the red pixel 20 </ b> R are formed on the support 11. In the photoresist removal step 42, the resist pattern 43 is removed.

  In the green layer forming step 37, a green layer 33G (third colored layer, see FIG. 11) is used by using a green light curable composition so as to cover the surface of the support 11 on which the green pixel forming region 39 and the like are formed. Form. The green layer 33G is formed so as to embed the green pixel formation region 39 while covering the blue pixel 20B and the red pixel 20R.

  In the exposure / development process 38, as in the exposure / development process 36, the green layer 33G is exposed and developed to form the green pixel 20G.

[Width and thickness of each colored pixel (pattern)]
The blue and red patterns 27B and 27R (the widths of the blue and red pixels 20B and 20R: the length of one side when each pixel is a square) are independently 0. 0 from the viewpoint of further improving the pattern formation limit. 5-1.7 micrometers is preferable and 0.6-1.5 micrometers is more preferable. Further, the width of the green pixel 20G (green pixel formation region 39) is preferably 0.5 to 1.7 μm and more preferably 0.6 to 1.5 μm for the same reason.

  The specific thickness of each colored pixel 20R, 20G, 20B is preferably 0.005 μm to 0.9 μm, more preferably 0.05 μm to 0.8 μm, and preferably 0.1 μm from the viewpoint of further improving the pattern formation limit. More preferably, -0.7 μm.

  Next, among the above steps, preferable modes of the resist pattern forming steps 29 and 40, the exposure / development step 36, the dry etching steps 30 and 41, and the photoresist removing steps 31 and 42 will be described.

[Resist pattern formation process]
The method for forming the resist pattern 34 in the resist pattern forming step 29 is not particularly limited, and a known photolithography technique can be appropriately optimized and used. For example, a positive or negative photosensitive resin composition (photoresist) described later is applied on the blue layer 33B and dried (preferably further pre-baked) to form a photoresist layer. The photoresist layer is then exposed to radiation and developed (preferably further post-baked) to form a resist pattern 34. As radiation used for exposure of the photoresist layer, g-line, h-line, and i-line are preferable, and i-line is particularly preferable. Further, the developer used for development is one that does not affect the colored layer containing the colorant and dissolves the uncured portion (exposed portion in the case of positive type, unexposed portion in the case of negative type). If it does not specifically limit. Specifically, a combination of various organic solvents or an alkaline aqueous solution can be used. The resist pattern 43 can be formed in the same manner.

[Photoresist]
As the photoresist, for example, a positive photosensitive resin composition is used. The positive photosensitive resin composition includes positive photosensitivity to ultraviolet rays (g rays, h rays, i rays), far ultraviolet rays including excimer lasers, electron beams, ion beams, and X rays. A positive resist composition suitable for resist can be used. Of the radiation, the exposure of the photosensitive resin layer is preferably g-line, h-line or i-line for the purpose of the present invention, and i-line is particularly preferable.

  Specifically, the positive photosensitive resin composition is preferably a composition containing a quinonediazide compound and an alkali-soluble resin. A positive-type photosensitive resin composition containing a quinonediazide compound and an alkali-soluble resin indicates that a quinonediazide group is decomposed by light irradiation with a wavelength of 500 nm or less to generate a carboxyl group, and as a result, the alkali-insoluble state becomes alkali-soluble. It is used as a positive photoresist. Since this positive photoresist has remarkably excellent resolution, it is used for manufacturing integrated circuits such as ICs and LSIs. Examples of the quinonediazide compound include a naphthoquinonediazide compound.

[Exposure and development process]
In the exposure / development process 36, a well-known photolithography technique can be appropriately optimized and used as in the above-described resist pattern formation process.

[Dry etching process]
The form of dry etching performed in the dry etching steps 30 and 41 and the etch back process is not particularly limited and can be performed in a known form. Representative examples of dry etching include JP-A-59-126506, JP-A-59-46628, JP-A-58-9108, JP-A-58-2809, JP-A-57-148706, JP-A-61-41102, and the like. Such a method as described in the publication is known.

[Preferred form of dry etching]
The dry etching in the present invention is preferably performed in the following form from the viewpoint of forming the pattern cross section closer to a rectangle and reducing the damage to the support 11. That is, using a mixed gas of fluorine-based gas and oxygen gas (O ₂ ), the first stage etching that performs etching to a region (depth) where the support 11 is not exposed, and after this first stage etching, A second stage etching is performed in which a mixed gas of nitrogen gas (N ₂ ) and oxygen gas (O ₂ ) is used, and etching is preferably performed up to a region (depth) where the support 11 is exposed, and the support 11 is exposed A form including over-etching performed after the etching is preferable. Hereinafter, a specific method of dry etching and the first stage etching, second stage etching, and over-etching will be described.

[Calculation of etching conditions]
Dry etching is performed by obtaining a configuration of etching conditions in advance by the following method.
(1) The etching rate (nm / min) in the first stage etching and the etching rate (nm / min) in the second stage etching are calculated respectively.
(2) The time for etching the desired thickness in the first stage etching and the time for etching the desired thickness in the second stage etching are respectively calculated.
(3) The first-stage etching is performed according to the etching time calculated in (2) above.
(4) The second stage etching is performed according to the etching time calculated in (2) above. Alternatively, the etching time may be determined by endpoint detection, and the second-stage etching may be performed according to the determined etching time.
(5) Overetching time is calculated with respect to the total time of (3) and (4) above, and overetching is performed.

[First-stage etching process]
The mixed gas used in the first stage etching process contains a fluorine-based gas and an oxygen gas (O ₂ ) from the viewpoint of processing the organic material that is the film to be etched into a rectangular shape. In addition, the first step etching process can avoid damage to the support 11 by performing etching until the region where the support 11 is not exposed.

[Second-stage etching process, over-etching process]
In the first stage etching process, etching is performed to a region where the support 11 is not exposed by a mixed gas of fluorine-based gas and oxygen gas, and then from the viewpoint of avoiding damage to the support 11, nitrogen gas and oxygen gas are mixed. Using the mixed gas, the etching process in the second stage etching process and the etching process in the overetching process are performed.

[Preferred ratio of etching amount]
The ratio between the etching amount in the first-stage etching process and the etching amount in the second-stage etching process needs to be determined so as not to impair the rectangularity due to the etching process in the first-stage etching process.

  The latter ratio in the total etching amount (the sum of the etching amount in the first stage etching step and the etching amount in the second stage etching step) is preferably in the range of more than 0% and not more than 50%. 20% is more preferable. Here, the etching amount is the thickness of the film to be etched remaining.

[Photoresist removal process]
In the photoresist removal steps 31 and 42, after the dry etching steps 30 and 41 are completed, the resist patterns 34 and 43 (photoresist layer) are removed with a dedicated stripping solution or solvent. In this embodiment, since the second stage etching process using the second mixed gas containing nitrogen gas and oxygen gas is performed, the photoresist layer can be more easily removed with a remover or a solvent. it can.

  The photoresist removing steps 31 and 42 are: (1) a first removing step of applying a stripping solution or a solvent on the resist patterns 34 and 43 to make the resist patterns 34 and 43 removable; and (2) It is preferable to include a second removal step of removing the resist patterns 34 and 43 using cleaning water.

  Examples of the first removal step include a paddle development step in which a stripping solution or a solvent is applied on at least the resist patterns 34 and 43 and is held for a predetermined time. Although there is no restriction | limiting in particular as time to make stripping solution or a solvent stagnant, It is preferable that it is several dozen seconds to several minutes.

  Examples of the second removal step include a step of removing the photoresist layer by spraying cleaning water onto the photoresist layer from a spray type or shower type spray nozzle. As the washing water, pure water can be preferably used. Further, examples of the injection nozzle include an injection nozzle in which the entire support is included in the injection range, and an injection nozzle that is a movable injection nozzle and in which the movable range includes the entire support. For example, the movable spray nozzle sprays the cleaning water while moving from the center of the support 11 to the end of the support 11 twice or more during the removal step. Thereby, the photoresist layer (resist pattern) can be effectively removed.

  The stripping solution generally contains an organic solvent, but may further contain an inorganic solvent. Examples of the organic solvent include (1) hydrocarbon compounds, (2) halogenated hydrocarbon compounds, (3) alcohol compounds, (4) ether or acetal compounds, (5) ketones or aldehyde compounds, (6) ester compounds, (7) polyhydric alcohol compounds, (8) carboxylic acids or acid anhydride compounds, (9) phenol compounds, (10) nitrogen compounds, (11) sulfur compounds, (12) Fluorine-containing compounds are exemplified.

  Further, the stripping solution used in the present invention preferably contains a nitrogen-containing compound, and more preferably contains an acyclic nitrogen-containing compound and a cyclic nitrogen-containing compound.

The acyclic nitrogen-containing compound is preferably an acyclic nitrogen-containing compound having a hydroxyl group. Examples include monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-ethylethanolamine, N, N-dibutylethanolamine, N-butylethanolamine, monoethanolamine, diethanolamine, and triethanolamine; Is monoethanolamine, diethanolamine or triethanolamine, more preferably monoethanolamine (H ₂ NCH ₂ CH ₂ OH).

  Examples of the cyclic nitrogen-containing compound include isoquinoline, imidazole, N-ethylmorpholine, ε-caprolactam, quinoline, 1,3-dimethyl-2-imidazolidinone, α-picoline, β-picoline, γ-picoline, 2-pipecoline, 3-pipecoline, 4-pipecoline, piperazine, piperidine, pyrazine, pyridine, pyrrolidine, N-methyl-2-pyrrolidone, N-phenylmorpholine, 2,4-lutidine, 2,6-lutidine and the like are preferable, N-methyl-2-pyrrolidone and N-ethylmorpholine are preferable, and N-methyl-2-pyrrolidone (NMP) is more preferable.

  The stripping solution used in the present invention preferably contains an acyclic nitrogen-containing compound and a cyclic nitrogen-containing compound, and among them, the acyclic nitrogen-containing compound is selected from monoethanolamine, diethanolamine and triethanolamine. More preferably, it contains at least one selected from the group consisting of N-methyl-2-pyrrolidone and N-ethylmorpholine as the cyclic nitrogen-containing compound, and monoethanolamine and N-methyl-2-pyrrolidone. It is more preferable to include.

  Further, the content of the acyclic nitrogen-containing compound is 9 parts by mass or more and 11 parts by mass or less with respect to 100 parts by mass of the stripping solution, and the content of the cyclic nitrogen-containing compound is 65 parts by mass or more and 70 parts by mass or less. It is desirable that Further, the stripping solution used in the present invention is preferably a mixture of a non-cyclic nitrogen-containing compound and a cyclic nitrogen-containing compound diluted with pure water.

  In the photoresist removing steps 31 and 42, the resist patterns 34 and 43 only have to be removed from the colored layers (blue and red patterns 27B and 27R, etc.), and the etching product is deposited on the side walls of the colored layers. In the case where an object is attached, the deposit may not be completely removed. Here, the deposit means an etching product deposited on the side wall of the colored layer.

  Furthermore, it is desirable to remove moisture absorbed in the colored layer after the photoresist removing steps 31 and 42 are completed. Specifically, it is desirable to perform a post-bake treatment at 90 ° C. to 200 ° C., more preferably 100 ° C. to 180 ° C. If the time is 1 minute or more and 10 minutes or less, the time efficiency of the production process is not lowered, and the conditions are sufficient to evaporate the absorbed moisture.

[Color filter material]
Next, a colored curable composition containing a colorant used for forming each colored pixel 20R, 20G, 20B, specifically, a photosensitive colored photocurable composition, and a non-photosensitive colored thermosetting The sex composition will be described.

[Colored photocurable composition]
The colored photocurable composition contains at least a colorant and a photocurable component. Among these, the “photo-curable component” is a photo-curable composition usually used in photolithography, and includes a binder resin (such as an alkali-soluble resin), a photosensitive polymerization component (such as a photopolymerization monomer), and a photopolymerization initiator. A composition containing at least such as can be used. For the colored photocurable composition, for example, the matters described in paragraph numbers 0017 to 0064 of JP-A-2005-326453 can be applied as they are.

[Colored thermosetting composition]
The colored thermosetting composition contains a colorant and a thermosetting compound, and the colorant concentration in the total solid content is preferably 50% by mass or more and less than 100% by mass. By increasing the colorant concentration, a thinner color filter 13 can be formed. In addition, when each colored pixel of the color filter is formed using a dry etching method, that is, using only a colored thermosetting composition, the photocurable component is removed from each colored pixel (each colored layer), and the cured component of each layer. By using only the thermosetting component, the ratio of the coloring component can be increased. As a result, each colored pixel is made thinner and good spectral characteristics can be obtained.

[Colorant]
The colorant used in the present invention is not particularly limited, and various conventionally known dyes and pigments can be used alone or in combination.

  Examples of the pigment include conventionally known various inorganic pigments or organic pigments. Further, considering that it is preferable to have a high transmittance, whether it is an inorganic pigment or an organic pigment, it is preferable to use a pigment having an average particle size as small as possible, and considering the handling properties, the average particle size of the pigment is 0.01 μm to 0.1 μm is preferable, and 0.01 μm to 0.05 μm is more preferable.

  The following can be mentioned as such a pigment. However, the present invention is not limited to these.

C. I. Pigment yellow 11,24,108,109,110,138,139,150,151,154,167,180,185;
C. I. Pigment orange 36, 71;
C. I. Pigment red 122,150,171,175,177,209,224,242,254,255,264;
C. I. Pigment violet 19, 23, 32;
C. I. Pigment blue 15: 1, 15: 3, 15: 6, 16, 22, 60, 66;
C. I. Pigment Black 1

[First color layer (blue layer)]
The colored layer of the first color is the blue layer 33B and contains a blue pigment. I. Pigment blue 15: 1, 15: 3, 15: 6, 16, 22, 60, 66; Furthermore, it is desirable to further contain a violet dye from the viewpoint of blue separability. Examples of violet dyes include C.I. I. Pigment violet 19, 23, 32; Thereby, even when the blue pattern / pixel is formed of a thin film, the spectral characteristics can be improved.

  In the present invention, when the colorant is a dye, the dye can be uniformly dissolved in the composition to obtain a non-photosensitive colored thermosetting resin composition. There is no restriction | limiting in particular as such a dye, A conventionally well-known dye can be used for color filters.

  The chemical structure includes pyrazole azo, anilino azo, triphenyl methane, anthraquinone, anthrapyridone, benzylidene, oxonol, pyrazolotriazole azo, pyridone azo, cyanine, phenothiazine, pyrrolopyrazole azomethine, Xanthene-based, phthalocyanine-based, benzopyran-based and indigo-based dyes can be used.

  The colorant content in the total solid content of the colored thermosetting composition is not particularly limited, but is preferably 30 to 60% by mass. By setting the content to 30% by mass or more, an appropriate chromaticity as a color filter can be obtained. Moreover, hardening can fully be advanced by setting it as 60 mass% or less, and the strength reduction as a film | membrane can be suppressed.

[Thermosetting compound]
The thermosetting compound is not particularly limited as long as the film can be cured by heating. For example, a compound having a thermosetting functional group can be used. As such a thermosetting compound, for example, a compound having at least one group selected from an epoxy group, a methylol group, an alkoxymethyl group, and an acyloxymethyl group is preferable.

  More preferable thermosetting compounds include (a) an epoxy compound, (b) a melamine compound, a guanamine compound, and a glycoluril substituted with at least one substituent selected from a methylol group, an alkoxymethyl group, and an acyloxymethyl group. Examples thereof include a compound or a urea compound, (c) a phenol compound, a naphthol compound, or a hydroxyanthracene compound substituted with at least one substituent selected from a methylol group, an alkoxymethyl group, and an acyloxymethyl group. Of these, polyfunctional epoxy compounds are particularly preferred.

  Although the total content of the thermosetting compound in the colored thermosetting composition varies depending on the material, it is preferably 0.1 to 50% by mass with respect to the total solid content (mass) of the colored thermosetting composition. 0.2-40 mass% is more preferable, and 1-35 mass% is especially preferable.

[Various additives]
In addition, the colored thermosetting composition has various additives as necessary, for example, a binder, a curing agent, a curing catalyst, a solvent, a filler, a polymer compound other than the above, as long as the effects of the present invention are not impaired. Surfactants, adhesion promoters, antioxidants, ultraviolet absorbers, aggregation inhibitors, dispersants and the like can be blended.

[binder]
The binder is often added at the time of preparing the pigment dispersion, does not require alkali solubility, and may be soluble in an organic solvent.

  The binder is preferably a linear organic polymer that is soluble in an organic solvent. Examples of such linear organic high molecular polymers include polymers having a carboxylic acid in the side chain, such as JP-A-59-44615, JP-B-54-34327, JP-B-58-12577, and JP-B-54-. No. 25957, JP-A-59-53836, JP-A-59-71048, methacrylic acid copolymer, acrylic acid copolymer, itaconic acid copolymer, crotonic acid copolymer, etc. Examples thereof include polymers, maleic acid copolymers, partially esterified maleic acid copolymers, and acidic cellulose derivatives having a carboxylic acid in the side chain are also useful.

  Among these various binders, from the viewpoint of heat resistance, polyhydroxystyrene resins, polysiloxane resins, acrylic resins, acrylamide resins, and acrylic / acrylamide copolymer resins are preferable. Acrylic resins, acrylamide resins, and acrylic / acrylamide copolymer resins are preferred.

  Examples of the acrylic resin include copolymers composed of monomers selected from benzyl (meth) acrylate, (meth) acrylic acid, hydroxyethyl (meth) acrylate, (meth) acrylamide, and the like, such as benzyl methacrylate / methacrylic acid, Each copolymer such as benzyl methacrylate / benzylmethacrylamide, KS resist-106 (manufactured by Osaka Organic Chemical Industry Co., Ltd.), cyclomer P series (manufactured by Daicel Chemical Industries, Ltd.) and the like are preferable.

  By dispersing the aforementioned colorant in these binders at a high concentration, it is possible to impart adhesion to the lower layer, etc., which also contributes to the coating surface state during spin coating and slit coating (colored layer formation). Yes.

[Curing agent]
When an epoxy resin is used as the thermosetting compound, it is preferable to add a curing agent. There are many types of curing agents for epoxy resins, and their properties, pot life with resin and curing agent mixture, viscosity, curing temperature, curing time, heat generation, etc. vary greatly depending on the type of curing agent used. An appropriate curing agent must be selected according to the purpose of use, use conditions, working conditions, and the like. The curing agent is explained in detail in Chapter 5 of Hiroshi Kakiuchi “Epoxy resin (Shojodo)”. Examples of curing agents are as follows.

  Those that act catalytically include tertiary amines, boron trifluoride-amine complexes, those that react stoichiometrically with functional groups of epoxy resins, polyamines, acid anhydrides, etc .; Examples include diethylenetriamine, polyamide resin, and medium temperature curing examples such as diethylaminopropylamine and tris (dimethylaminomethyl) phenol; examples of high temperature curing include phthalic anhydride and metaphenylenediamine. In terms of chemical structure, in the case of amines, diethylenetriamine as an aliphatic polyamine; metaphenylenediamine as an aromatic polyamine; tris (dimethylaminomethyl) phenol as a tertiary amine; phthalic anhydride as an acid anhydride; polyamide resin Polysulfide resin, boron trifluoride-monoethylamine complex; Synthetic resin initial condensate includes phenol resin, dicyandiamide and the like.

  These curing agents react with an epoxy group by heating and polymerize to increase the crosslinking density and cure. For thinning, both the binder and the curing agent are preferably as small as possible. In particular, the curing agent is 35% by mass or less, preferably 30% by mass or less, more preferably 25% by mass or less with respect to the thermosetting compound. It is preferable that

[Curing catalyst]
In order to realize a high colorant concentration in the present invention, curing by reaction between epoxy groups is effective in addition to curing by reaction with the curing agent. For this reason, a curing catalyst can be used without using a curing agent. The addition amount of the curing catalyst is about 1/10 to 1/1000, preferably about 1/20 to 1/500, more preferably about 1/30 to the epoxy resin having an epoxy equivalent weight of about 150 to 200. It is possible to cure with a slight amount of about 1/250.

[solvent]
The colored thermosetting composition is used as a solution dissolved in various solvents. The solvent is not particularly limited as long as the solubility of each component and the coating property of the colored thermosetting composition are satisfied.

[Dispersant]
Moreover, the said dispersing agent is added in order to improve the dispersibility of a pigment. As the dispersant, known ones can be appropriately selected and used, and examples thereof include a cationic surfactant, a fluorosurfactant, and a polymer dispersant.

  As these dispersants, many types of compounds are used. For example, phthalocyanine derivatives (commercially available products EFKA-745 (manufactured by Efka)), Solsperse 5000 (manufactured by Nippon Lubrizol); organosiloxane polymer KP341 (Shin-Etsu) (Made by Chemical Industry Co., Ltd.), (meth) acrylic acid type (co) polymer polyflow No.75, No.90, No.95 (made by Kyoeisha Yushi Chemical Co., Ltd.), W001 (made by Yusho Co., Ltd.) ) And other cationic surfactants; polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate , Sol Nonionic surfactants such as tan fatty acid esters; Anionic surfactants such as W004, W005, W017 (manufactured by Yusho Co., Ltd.); EFKA-46, EFKA-47, EFKA-47EA, EFKA polymer 100, EFKA polymer 400, EFKA polymer 401, EFKA polymer 450 (manufactured by Morishita Sangyo Co., Ltd.), disperse aid 6, disperse aid 8, disperse aid 15, disperse aid 9100 (manufactured by San Nopco) Agents: Solsperse 3000, 5000, 9000, 12000, 13240, 13940, 17000, 24000, 26000, 28000 and other Solsperse dispersants (manufactured by Nippon Lubrizol); Adeka Pluronic L31, F38, L42, L44, L61, L64 F68, L72, P95, F77, P84, F87, P94, L101, P103, F108, L121, P-123 (manufactured by Asahi Denka Co.) and Isonetto S-20 (manufactured by Sanyo Chemical Co.) and the like

  The said dispersing agent may be used independently and may be used in combination of 2 or more type. Usually, the amount of the dispersant added to the colored thermosetting composition is preferably about 0.1 to 50 parts by mass with respect to 100 parts by mass of the pigment.

[Other additives]
Moreover, various additives can be further added to the colored curable composition as necessary.

  Next, each process which comprises the color filter manufacturing process 22 is demonstrated in detail using FIGS. However, the present invention is not limited to the following description. In order to prevent complication of the drawing, the case where the color filter 13 of 3 × 3 = 9 pixels is manufactured will be described here, but it can be manufactured in the same manner when the number of pixels is increased.

  As shown in FIGS. 3A and 3B, in the blue layer forming step 28, a blue thermosetting composition containing a blue dye and a violet dye is applied onto the support 11 using a known spin coater. Next, the support 11 is baked (post-baked) by a known heating device such as a hot plate or an oven. Thereby, the coating film of the blue thermosetting composition is thermoset, and the blue layer 33B is formed on the support 11 with a predetermined film thickness.

  As shown in FIGS. 4A and 4B, in the resist pattern forming step 29, a photoresist is applied onto the blue layer 33B using a spin coater, and then the support 11 is pre-baked by a heating device. As a result, the photoresist is cured, and a photoresist layer is formed on the blue layer 33B.

  Next, using a well-known exposure apparatus (i-line stepper), the photoresist layer is irradiated with exposure light, and this photoresist layer is exposed. For example, when a positive photoresist is used, the exposure light beam is applied to a region other than the region where the blue pattern 27B is formed. After this exposure process, the exposed photoresist layer is developed using a known developer. Further, after the development processing, post-baking processing is performed by a heating device. Thereby, a resist pattern 34 having an opening 34a corresponding to the blue pattern 27B is formed on the blue layer 33B.

  As shown in FIGS. 5A and 5B, in the dry etching step 30, the blue layer 33B is dry etched using a known dry etching apparatus with the resist pattern 34 as a mask. This dry etching is performed in the three stages of the first stage etching, the second stage etching, and the overetching. As a result, the blue layer 33 </ b> B exposed from the opening 34 a of the resist pattern 34 is removed, and a striped blue pattern 27 </ b> B is formed on the support 11.

  As shown in FIGS. 6A and 6B, in the photoresist removal step 31, a first removal step of applying a stripping solution or a solvent onto the resist pattern 34 and the resist pattern 34 are removed using cleaning water. A 2nd removal process is performed. As a result, the resist pattern 34 is removed from the blue pattern 27B.

  As shown in FIGS. 7A and 7B, in the red layer forming step 35, the same process as in the blue layer forming step 28 is performed to cover the blue pattern 27B on the support 11 and A red layer 33R made of a photocurable composition is formed so as to embed a region between the patterns.

  As shown in FIGS. 8A and 8B, in the exposure / development process 36, an exposure device (i-line stepper) is used to irradiate the red layer 33R with exposure light, and the red layer 33R is exposed. To do. For example, the exposure light beam is applied to a region where the red pattern 27R is formed (a region other than the region where the blue pattern 27B is formed). Next, the exposed red layer 33R is developed using a known developer, and then post-baked. Thereby, a striped red pattern 27R parallel to the blue pattern 27B is formed so as to fill a gap between the blue patterns 27B.

  In FIG. 8B, the surface of the blue pattern 27B and the surface of the red pattern 27R are substantially flush, but the film thickness (height) of the red pattern 27R is the film thickness of the blue pattern 27B. May be larger. In this case, a flattening process is performed after the end of the green pixel forming step 25.

  Thus, a stripe pattern in which the blue pattern 27B and the red pattern 27R are alternately arranged is formed on the support 11. Further, the blue pattern 27B and the red pattern 27R are formed such that adjacent patterns touch each other on the surface. In the present embodiment, since the colored pixels 20R, 20G, and 20B are all square, it is desirable that the ratio of the widths of the patterns 27B and 27R is 1: 1. However, this does not apply depending on the device design.

  As shown in FIGS. 9A to 9C, in the resist pattern forming step 40 of the green pixel region forming step 25a, the same processing as the resist pattern forming step 29 is performed, and the blue pattern 27B and the red pattern 27R are processed. A resist pattern 43 having an opening 43a corresponding to the green pixel formation region 39 is formed thereon.

  As shown in FIGS. 10A to 10C, in the dry etching process 41, the blue pattern 27B and the red pattern 27R are dry-etched by using the resist pattern 43 as a mask by the same method as the dry etching process 30 described above. . As a result, both the patterns 27B and 27R exposed from the opening 43a of the resist pattern 43 are removed, and the green pixel formation region 39 is formed on the support 11 in a checkered pattern. At the same time, the blue pixel 20 </ b> B and the red pixel 20 </ b> R are formed on the support 11.

  As shown in FIGS. 11A to 11C, in the photoresist removal process 42, the first removal process and the second removal process are performed in the same manner as the photoresist removal process 42 described above, and the blue pixels 20B and The resist pattern 43 is removed from the red pixel 20R.

  As shown in FIGS. 12A to 12C, in the green layer forming step 37, the blue pixel 20 </ b> B and the red pixel 20 </ b> R are formed on the support 11 by performing the same process as in the blue layer forming step 28 described above. A green layer 33G is formed so as to embed the green pixel formation region 39 while covering.

  As shown in FIGS. 13A to 13C, in the exposure / development process 38, an exposure light (irradiation step) is used to irradiate an area corresponding to the green pixel formation area 39 of the green layer 33G with exposure light. Then, after this green layer 33G is subjected to pattern exposure, the green pixel 20G is formed on the green pixel formation region 39 by performing development processing and post-baking processing in the same manner as the exposure / development process 36 described above. If the surfaces of the colored pixels 20R, 20G, and 20B are not flat, a flattening process (such as a polishing process) is performed on each of these surfaces.

  Thus, all the steps of the color filter manufacturing process 22 are completed, and the color filter 13 in which the colored pixels 20R, 20G, and 20B are two-dimensionally arranged on the support 11 is formed.

  Next, the color filter manufacturing process 46 according to the second embodiment of the present invention will be described with reference to FIG. The color filter manufacturing process 46 is basically the same as the color filter manufacturing process 22 of the first embodiment. However, in the color filter manufacturing process 46, the red pattern 27R and the green pixel 20G are formed by a flattening method. For this reason, the color filter manufacturing process 46 includes a red pattern forming process 47 and a green pixel forming process 48 instead of the red pattern forming process 24 and the green pixel forming process 25 described above.

  The red pattern forming process 47 includes a red layer forming process 49 and a planarization process 50. The green pixel forming step 48 includes the aforementioned green pixel region forming step 25a, a green layer forming step 51, and a planarization processing step 52.

  In the red layer forming step 49, a red layer 33R is formed on the support 11 on which the blue pattern 27B is formed, using a red thermosetting composition. Similarly, in the green layer forming step 51, the green layer 33G is formed on the support 11 on which the green pixel forming region 39 and the like are formed using the green thermosetting composition.

  In the flattening process 50, the surface of the red layer 33R is flattened until the blue pattern 27B is exposed to form the red pattern 27R. In the flattening process step 52, the green pixel 20G is formed by flattening the surface of the green layer 33G until the blue pixel 20B and the red pixel 20R are exposed.

  As the planarization process, an etch-back process in which the entire exposed surface of the support 11 is dry-etched is preferable from the viewpoint of simplification of the manufacturing process and manufacturing cost. Further, instead of the etch-back process, a polishing process such as a chemical mechanical polishing (hereinafter referred to as “CMP”) process in which all exposed surfaces of the support 11 are chemically and mechanically polished may be performed. Good.

[Etch back treatment]
For a preferred form of the etch back process, refer to the preferred form of the dry etching step.

[Polishing]
As a slurry used for polishing (CMP) treatment, it is preferable to use an aqueous solution having a pH of 9 to 11 containing 0.5 to 20% by mass of SiO ₂ abrasive grains having a particle size of 10 to 100 nm. As the polishing pad, a soft type such as continuous foaming urethane can be preferably used. Using the above slurry and polishing pad, polishing can be performed under the conditions of slurry flow rate: 50 to 250 ml / min, wafer pressure: 0.2 to 5.0 psi, retainer ring pressure: 1.0 to 2.5 psi. . In addition, after the polishing process is completed, a cleaning process for precisely cleaning the surface to be polished and a dehydration process for performing a dehydration bake (preferably at 100 to 200 ° C. for 1 to 5 minutes) (dehydration process) are performed.

  Next, each process constituting the color filter manufacturing process 46 will be described in detail. The color filter manufacturing process 46 is the same as the color filter manufacturing process 22 of the first embodiment except that a planarization method is used when forming the red pattern 27R and the green pixel 20G. The description will be made with reference to the drawings (FIGS. 3 to 13) described in the first embodiment.

  After the blue pattern 27B is formed on the support 11 in the blue pattern forming step 23 (see FIGS. 3 to 6), the red layer forming step 49 performs the same process as the blue layer forming step 28 described above, A red layer 33R made of a thermosetting composition is formed on the support 11 (see FIG. 7).

  In the flattening process 50, the surface of the red layer 33R is etched back using a dry etching apparatus or a polishing (CMP) apparatus until the red layer 33R on the blue pattern 27B is removed and the blue pattern 27B is exposed. Alternatively, polishing is performed. As a result, a red pattern 27R is formed and the surfaces of both patterns 27B and 27R are flattened (see FIG. 8). Furthermore, for example, after the etch back process is first performed on the red layer 33R, the remaining red layer 33R on the blue pattern 27B may be removed by the polish process, and the etch back process and the polish process may be performed in combination. .

  Next, after the green pixel region forming step 25a (see FIGS. 9 to 11) is performed as described above, in the green layer forming step 51, the green layer 33G made of the thermosetting composition is formed on the support 11. Form (see FIG. 12).

  In the planarization process step 52, the green layer 33G of the green layer 33G is removed until the green layer 33G on the blue pixel 20B and the red pixel 20R is removed using a dry etching apparatus or a polishing apparatus as in the above-described planarization process step 50. The surface is etched back or polished, or both processes are performed (see FIG. 13). Thereby, the green pixel 20G is formed and the surface of each colored pixel 20R, 20G, 20B is flattened.

  Thus, all the steps of the color filter manufacturing process 46 are completed, and the color filter 13 is formed as in the first embodiment.

  In the second embodiment, in the planarization process step 50, the surface of the red layer 33R is planarized until the blue pattern 27B is exposed, but the present invention is not limited to this. For example, as shown in FIGS. 15A and 15B, the flattening process may be terminated in a state where the red layer 33R remains on the blue pattern 27B. In this case, the blue pattern 27B is prevented from being etched or polished. The red layer 33R on the blue pattern 27B may be removed in the flattening process step 52, which is a subsequent step.

  Next, the color filter manufacturing process 55 (see FIG. 17) according to the third embodiment of the present invention will be described. In the color filter manufacturing process 55, a color filter 56 (see FIG. 16) different from the color filter 13 described above is formed.

  As shown in FIG. 16, the color filter 56 has the same configuration as the color filter 13 described above except that a stopper layer 57 used for detecting the end point of the flattening process is formed on the blue pixel 20B. . In addition, about the same thing as a color filter 13 (solid-state imaging device 10) on a function and a structure, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  The stopper layer 57 is preferably a layer having an etching rate in the etch back process or a polishing rate in a polishing process such as CMP lower than that of the color layers 33R and 33G. Further, the stopper layer 57 is formed of a curable composition that is transparent to visible light. This eliminates the need to completely remove the stopper layer 57 from the blue pixel 20B. Here, being transparent to visible light means that the transmittance of visible light is 95% or more.

  As shown in FIG. 17, the color filter manufacturing process 55 is the same as the color filter manufacturing process 46 (see FIG. 14) of the second embodiment except that the blue pattern forming process 59 is different. The blue pattern forming step 59 is different from the first embodiment in that a stopper layer forming step 60 is provided between the blue layer forming step 28 and the resist pattern forming step 29.

  The stopper layer forming step 60 uses a curable composition that is a material of the stopper layer 57 on the blue layer 33B formed in the blue layer forming step 28, so as to distinguish it from the stopper layer (stopper layer 57, hereinafter, An entire surface stopper layer 62 (see FIG. 18) 62 is formed. In the resist pattern forming step 29, the above-described resist pattern 34 is formed on the entire surface stopper layer 62. In the dry etching step 30, the entire surface stopper layer 62 and the blue layer 33B are dry-etched using the resist pattern 34 as a mask to form a striped stopper pattern layer 62a (see FIG. 20) and a blue pattern 27B. In the photoresist removing step 31, the resist pattern 34 is removed from the stopper pattern layer 62a.

  The red pattern forming process 47 and the green pixel forming process 48 are basically the same as those in the second embodiment. However, in the flattening process 50 of the red pattern forming process 47, the surface of the red layer 33R is flattened until the stopper pattern layer 62a is exposed. Further, in the dry etching step 41 of the green pixel forming step 48, the stopper pattern layer 62a is dry etched to form the stopper layer 57 on the surface of the blue pixel 20B. Further, in the flattening process step 52, the surface of the green layer 33G is flattened until the stopper layer 57 is exposed. Whether or not the stopper layer 57 (same for the stopper pattern layer 62a) is exposed (end point of the planarization process) can be confirmed by the following method.

  When the etch back process is performed, for example, the end point of the planarization process can be confirmed based on the presence or absence of plasma emission of the reaction product generated by dry etching (plasma etching) of the stopper layer 57. Further, when the polishing process is performed, for example, the surface to be polished is irradiated with the inspection light and the reflected light is measured, and based on whether or not the light having a specific frequency is absorbed by the stopper layer 57. The end point of the flattening process can be confirmed.

  During the planarization process, the surfaces of the blue pattern 27B and the blue pixel 20B are protected by the stopper pattern layer 62a and the stopper layer 57, respectively. Or being damaged more effectively. Thereby, control of the transmission spectral characteristics of the blue pixel 20B of the color filter 56 is further facilitated.

[Curable composition]
As the curable composition for forming the stopper layer 57, a composition containing a polymer compound that can be cured by heat can be preferably used. As the polymer compound, for example, a polysiloxane polymer and a polystyrene polymer are preferable. Among these, a material known as a spin-on-glass (SOG) material, or a thermosetting composition mainly composed of a polystyrene derivative or a polyhydroxystyrene derivative is more preferable.

  As an index indicating the etching resistance of the curable composition, for example, Onishi parameters (reference documents JP-A Nos. 2004-294638 and 2005-146182) can be used. In the present invention, when the parameter value of the colored curable composition is 3.5 to 4.5, the parameter value of the curable composition forming the stopper layer 57 is 2.5 or less. Therefore, it can be determined that the selectivity to the colored curable composition layer can be ensured (the stopper layer 57 is difficult to be etched). The Onishi parameter can be calculated by the following formula (I).

  (C + O + H) / (C−O) Formula (I)

  C, O, and H in the formula (I) each represent the number of moles of carbon atom, oxygen atom, and hydrogen atom in the structural repeating unit of the polymer. An example of calculating Onishi parameters is shown below. It should be noted that the calculation was performed by rounding off the three decimal places.

Example 1. Fluorene acrylate compound (C + O + H) / (CO) = (33 + 6 + 25) / (33-6) = 2.37
Example 2. Polyhydrostyrene derivative (C + O + H) / (C−O) = (8 + 1 + 8) / (8-1) = 2.42

  Next, each step of the color filter manufacturing step 55 will be described in detail with reference to FIGS. In (A) of each figure, “BS” indicates that the stopper layers 57, 62, and 62a are stacked on the blue layer 33B, the blue pattern 27B, and the blue pixel 20B.

[Blue pattern forming process]
As shown in FIGS. 18A and 18B, after the completion of the blue layer forming step 28, in the stopper layer forming step 60, the curable composition is applied onto the blue layer 33 by using a spin coater and a heating device. The whole surface stopper layer 62 is formed on the blue layer 33B by baking.

  The following steps are basically the same as those in the first embodiment. As shown in FIGS. 19A and 19B, a resist pattern 34 is formed on the entire stopper layer 62 in the resist pattern forming step 29. Is done. Next, as shown in FIGS. 20A and 20B, after the blue pattern 27B and the stopper pattern layer 62a are formed in the dry etching step 30, as shown in FIGS. In the photoresist removing step 31, the resist pattern 34 is removed.

[Red pattern formation process]
As shown in FIGS. 22A and 22B, after the red layer 33R is formed on the support 11 in the red layer forming step 49, as shown in FIGS. In the chemical conversion treatment step 50, an etch-back process or a polishing process (both are possible) is performed on the surface of the red layer 33R using a dry etching apparatus or a polishing apparatus.

  When the stopper pattern layer 62a is exposed by the etch-back process, the plasma emission of the reaction product generated by etching the stopper pattern layer 62a is confirmed. Further, when the stopper pattern layer 62a is exposed by the polishing process, absorption of light of a specific frequency by the stopper pattern layer 62a is confirmed. When these confirmations are made, the flattening process is terminated. Thereby, the red pattern 27R is formed, and the surface of the blue pattern 27B (including the stopper pattern layer 62a) and the red pattern 27R is flattened.

[Green pixel forming process]
As shown in FIGS. 24A to 24C, in the resist pattern forming step 40, a resist pattern 43 is formed on the stopper pattern layer 62a and the red pattern 27R. Next, as shown in FIGS. 25A to 25C, after the blue pixel 20B, the red pixel 20R, the stopper layer 57, and the green pixel formation region 39 are formed in the dry etching process 41, FIG. As shown in (C), in the photoresist removing step 42, the resist pattern 43 is removed.

  As shown in FIGS. 27A to 27C, after the green layer 33G is formed on the support 11 in the green layer forming step 37, as shown in FIGS. In the flattening process 52, the surface of the green layer 33G is flattened until the stopper layer 57 is exposed in the same manner as in the flattening process 50 described above. Thereby, the green pixel 20G is formed, and the stopper layer 57, the red pixel 20R, and the green pixel 20G on the blue pixel 20B are flattened.

  Thus, all the steps of the color filter manufacturing step 55 are completed, and the color filter 56 in which the colored pixels 20R, 20G, and 20B are two-dimensionally arranged on the support 11 is formed.

  In the red pattern forming step 47 of the third embodiment, the surface of the red layer 33R is subjected to flattening processing (etch back processing, polishing processing) to form the red pattern 27R. However, the present invention is limited to this. Instead, the red layer 33R may be patterned by a dry etching method to form the red pattern 27R.

  Specifically, as shown in FIG. 29, in the color filter manufacturing process 55 of the third embodiment, a red pattern forming process 47 a is executed instead of the red pattern forming process 47. In the red pattern forming process 47a, a resist pattern forming process 63, a dry etching process 64, and a photoresist removing process 65 are executed instead of the planarization process 50 (see FIGS. 14 and 17).

  As shown in FIGS. 30A and 30B, in the resist pattern forming step 63, a resist pattern (second resist pattern) 66 is formed using a photoresist on the red layer 33R made of the thermosetting composition. To do. The resist pattern 66 is formed so as to cover an area corresponding to the red pattern 27R and expose the other areas. Next, when the red layer 33R is dry-etched using the resist pattern 66 as a mask in a dry etching step 64, a red pattern 27R is formed on the support 11. In the photoresist removing process 65, the resist pattern 66 is removed from the red pattern 27R.

  The film thickness (height) of the red pattern 27R formed in the red pattern forming process 47a is larger than the film thickness of the blue pattern 27B, but is flattened in the flattening process 52 of the green pixel forming process 48. There is no problem.

  The red pattern forming step 47a may be executed instead of the red pattern forming steps 24 and 47 in the color filter manufacturing steps 22 and 46 of the first and second embodiments. For example, when the red pattern forming step 47a is executed in the color filter manufacturing step 22 (see FIG. 2) of the first embodiment, the blue and red patterns 27B and 27R are formed by dry etching (FIGS. 3 to 6, FIG. 30). The green pixel 20G is formed by a photolithography method (see FIGS. 12 and 13).

  Further, as shown in FIG. 31, in the color filter manufacturing process 55 of the third embodiment, instead of the green pixel forming process 48, the green pixel 33G is patterned by the dry etching method to form the green pixel 20G. The forming step 48a may be executed. In the green pixel forming process 48a, a resist pattern forming process 69, a dry etching process 70, and a photoresist removing process 71 are executed instead of the planarization process 52 (see FIGS. 14 and 17). The steps 69 to 71 are basically the same as the resist pattern forming step 63, the dry etching step 64, and the photoresist removing step 65 (see FIG. 29) described above, and thus description thereof is omitted.

  The green pixel forming step 48a may be executed in place of the green pixel forming steps 25 and 48 in the color filter manufacturing steps 22 and 46 of the first and second embodiments.

  As described above, according to the present invention, the stripe-shaped blue pattern 27B is formed on the support 11 and the stripe-shaped red pattern 27R is formed on the support 11 so as to fill the gap between the blue patterns 27B. The color filters 13 and 56 are manufactured through the step, the step of forming the green pixel forming region 39 on the support 11, and the step of forming the green pixel 20G of the third color in the green pixel forming region 39. Therefore, it is possible to reduce the step of directly forming the isolated pattern (colored pixel). Thereby, the roundness of the corners of the isolated pattern can be suppressed when each pixel is formed.

  Furthermore, when a repetitive pattern such as a stripe pattern is formed by the photolithography method, the contrast of the edge of the pattern image formed on the colored layer at the time of exposure is sufficiently high compared to the case of forming an isolated pattern. can do. In addition, since the contrast in the longitudinal direction of the stripe pattern is constant, a state in which the edge (corner) of the pattern is rounded does not occur. As a result, the rectangularity of each colored pixel can be improved as compared with the prior art. Further, even when the stripe pattern is formed by the dry etching method, the rounding of the corners of the cross-sectional shape as when the isolated pattern is processed by the dry etching can be suppressed. Can be improved.

  Further, as in the second and third embodiments, in addition to the blue pattern 27B, the red pattern 27R and the green pixel 20G are formed by a photolithographic method using a colored photosensitive composition whose pattern rectangularity is inferior to the photoresist. In addition, when formed using a photoresist having excellent pattern rectangularity and a dry etching method / CMP method (planarization treatment), the rectangularity of each of the colored pixels 20R, 20G, and 20B can be further improved.

  Furthermore, since the blue pattern 27B and the blue pixel 20B are formed by the dry etching method as the first color pixel (colored pattern, colored layer), photopolymerization due to lack of exposure light, which is a problem in the photolithography method. Due to the shortage, the dissolution of the blue pixel does not occur at the time of development, so that the blue pixel 20B can be prevented from peeling off. In addition, the blue pixel 20B was difficult to be thinned when formed by a photolithography method (colored photosensitive composition), but by forming it by a dry etching method (colored thermosetting composition), a thin film was formed. Can be realized.

  In addition, since the isolated pattern is not processed in the present invention, the generation of a blank area (see FIG. 32A) in the area where the corners of the colored pixels 20R, 20G, and 20B are gathered, and the colored pixels 20R, 20G, and 20B Generation of a dent (see FIG. 32B) in the vicinity of the boundary can be prevented. The pattern that forms the green region (here, checkered pattern) is formed by dry etching using a photoresist, and is formed through a process of removing unnecessary portions after embedding, thus forming an isolated pattern. The roundness of the corners of each pattern is smaller than in the case of doing so. Thereby, the formation limit of the pattern (each colored pixel) can be improved, and the pattern can be made finer and thinner.

  Furthermore, the solid-state imaging device 10 of the present invention includes the color filters 13 and 56 manufactured in each of the above steps, so that the color reproducibility is improved. The color filters 13 and 56 are particularly suitable for a high-resolution solid-state imaging device that exceeds 1 million pixels.

  In the above embodiment, the red layer 33R is formed as the second color layer and the green layer 33G is formed as the third color layer. However, the present invention is not limited to this, and the order is The reverse may be possible. The present invention can also be applied when the color filter is composed of four or more colored pixels.

  In the second and third embodiments, the case where either the etch back process or the polishing process is performed in the planarization process steps 50 and 52 has been described, but both may be performed together. Further, various planarization processes other than the etch back process and the polishing process may be performed.

  In the above embodiment, the method for producing a color filter used in a solid-state imaging device has been described. However, the present invention is not limited to this, and the present invention is also applied to the production of a color filter used in a liquid crystal display or the like. Can be applied.

  EXAMPLES Hereinafter, Examples 1-4 for demonstrating the effect of this invention are shown, and this invention is demonstrated concretely, However, This invention is not limited to a following example, unless the main point is exceeded. . Unless otherwise specified, “part” is based on mass. In the following steps, when processing using a commercially available processing solution was performed, processing was performed according to the method specified by the manufacturer of each processing solution unless otherwise specified. As Examples 1 to 3, color filters 13 and 56 manufactured in the color filter manufacturing steps 22, 46 and 55 of the first to third embodiments were prepared. In Examples 2 and 3, a polishing (CMP) process was performed as a planarization process. Further, as Example 4, a color filter 13 manufactured by performing an etch-back process instead of a polishing process in the green pixel forming process 48 of Example 2 (entire surface stopper layer not provided) was prepared.

[Example 1]
Example 1 was produced under the following conditions. First, the following blue thermosetting composition was prepared as a material for the blue pixel 20B.

<Blue thermosetting composition>
Before preparing the blue thermosetting composition, the following blue pigment dispersion was first prepared.
-"Pigment Blue 15: 6" 125 parts by mass-"Pigment Violet" 25 parts by mass-Dispersant PLADDED211 (manufactured by Enomoto Kasei Co., Ltd.) 40 parts by mass-Benzyl methacrylate / glycidyl methacrylate copolymer 15 parts by mass -PGMEA 755 parts by mass Each of the above materials was agitated with a homogenizer, and then finely dispersed with a disperser (Dispermat, manufactured by GETZMANN) using 0.3 mm zirconia beads for 5 hours to give a blue pigment. A dispersion was prepared.

Next, a non-photosensitive coloring composition, that is, a blue thermosetting composition was prepared by further adding a thermosetting resin to the blue pigment dispersion.
EHPE-3150 0.8 part by mass (based on the blue pigment dispersion)
Furthermore, PGMEA was added to the blue pigment dispersion and the thermosetting resin, and the solid content of the composition was diluted to 13.0%.

<Blue pattern formation process>
The blue colored composition is coated on the support 11 with a spin coater so as to form a coating film having a film thickness of 0.5 μm, and then heated (post bake) at 220 ° C. for 5 minutes using a hot plate. And the coating film was cured to form a blue layer 33B.

  Next, a positive photoresist “FHi622BC” (manufactured by FUJIFILM Electronics Materials) was applied and prebaked at 90 ° C. for 1 minute to form a photoresist layer having a thickness of 0.8 μm.

Subsequently, the photoresist layer was subjected to pattern exposure using an i-line stepper (manufactured by Canon Inc.) at an exposure amount of 350 mJ / cm ² , and then heat treatment (post bake) at 110 ° C. for 1 minute. Next, after developing for 1 minute with the developer “FHD-5” (manufactured by Fuji Film Electronics Materials), rinsing with pure water and drying by spin drying were performed. Thereafter, a post-bake treatment was further performed at 110 ° C. for 1 minute to form a resist pattern 34. The LINE (pattern width) & SPACE (gap width) sizes of the resist pattern 34 were LINE: 1.25 μm and SPACE: 1.15 μm, and the film thickness after post-baking was 0.7 μm.

  Next, dry etching of the blue layer 33B was performed in the following procedure using the resist pattern 34 as an etching mask.

RF power: 800 W, antenna bias: 400 W, wafer bias: 200 W, chamber internal pressure: 4.0 Pa, substrate temperature: 50 ° C., mixed gas in dry etching apparatus (H-621, manufactured by Hitachi High-Technologies Corporation) The gas type and flow rate were set to CF ₄ : 80 mL / min. , O ₂ : 40 mL / min. , Ar: 800 mL / min. As a result, the first-stage etching process for 75 seconds was performed. Under this etching condition, the amount of scraping of the blue layer 33B was 438 nm, that is, the etching amount was 87%, and there was a remaining film of about 62 nm.

Next, in the same etching chamber, RF power: 600 W, antenna bias: 100 W, wafer bias: 250 W, chamber internal pressure: 2.0 Pa, substrate temperature: 50 ° C., gas mixture type and flow rate of N ₂ : 500 mL / min. , O ₂ : 50 mL / min. , Ar: 500 mL / min. (N ₂ / O ₂ / Ar = 10/1/10), the second etching process and the over-etching process were performed with the over-etching rate in the total etching being 20%.

  The etching rate of the blue layer 33B under the second-stage etching conditions was 600 nm / min or more, and it took about 9 seconds to etch the remaining film of the blue layer 33B. The etching time was calculated by adding 75 seconds of the first stage etching time and 9 seconds of the second stage etching time. As a result, the etching time was 75 + 9 = 84 seconds, the overetching time was 84 × 0.2≈17 seconds, and the total etching time was set to 84 + 17 = 101 seconds.

  After performing dry etching under the above conditions, the resist pattern 34 is removed by performing a stripping process for 120 seconds using a photoresist stripping solution “MS230C” (manufactured by FUJIFILM Electronics Materials), and further using pure water. Washing and spin drying were performed. Thereafter, a dehydration baking process at 100 ° C. for 2 minutes was performed on a hot plate. Thus, a striped blue pattern 27B was obtained. The size of LINE & SPACE of this blue pattern 27B was LINE 1.2 μm and SPACE 1.2 μm.

<Red pattern formation process>
Next, a red photocurable composition “SR-5000L” (FUJIFILM Electronics Materials Co., Ltd.) is formed in the same manner as in the formation of the blue layer 33B so as to cover the surface of the support 11 on which the blue pattern 27B is formed. After forming a 0.65 μm thick coating film, a red plate 33R was formed by performing a post-bake treatment at a coating film temperature or an ambient temperature of 100 ° C. for 2 minutes using a hot plate.

Subsequently, the red layer 33R was pattern-exposed with an exposure of 150 mJ / cm ² using an i-line stepper (manufactured by Canon Inc.), and 1 with a developer “CD-2060” (manufactured by Fuji Film Electronics Materials). After performing the developing process for 1 minute, the rinse process and the drying process were performed. Thereafter, a post-baking process was further performed at 220 ° C. for 5 minutes to form a striped red pattern 27R so as to fill the gap between the blue patterns 27B. The size of LINE & SPACE of the red pattern 27R was LINE 1.2 μm and SPACE 1.2 μm, and the film thickness after post-baking was 0.5 μm.

  Further, the red pattern 27R and the blue pattern 27B were formed such that adjacent patterns contact each other on the surface (see FIG. 8B). Furthermore, the surfaces of the blue and red patterns 27B and 27R were formed flat (level). That is, the surfaces of both patterns 27B and 27R were the same height with respect to the support 11.

<Green pixel formation process>
Subsequently, a photoresist layer having a thickness of 0.8 μm was formed on the blue and red patterns 27B and 27R under the same conditions as those for forming the resist pattern 34 described above, and then a resist pattern 43 was formed. . However, the exposure amount at the time of pattern exposure was changed to 250 mJ / cm ² . The openings 43a of the resist pattern 43 are arranged in a checkered pattern and are each formed into a 1.2 μm square.

  Next, dry etching of the blue and red patterns 27B and 27R was performed using the resist pattern 43 as an etching mask. Of the dry etching conditions in the blue pattern forming step 23, the first stage etching time is 60 seconds, the second stage etching time is 25 seconds, the etching time is 60 + 25 = 85 seconds, and the overetching time is 85 × 0. .2 = 17 seconds, respectively, and the dry etching process was performed under the condition that the total etching time was 85 + 17 = 102 seconds.

  The amount of scraping of the blue pattern 27B in the first-stage etching was 350 nm, and the amount of scraping of the red pattern 27R was 423 nm, which were 70% and 84%, respectively. Therefore, after completion of the first stage etching, the remaining film thicknesses of the blue and red patterns 27B and 27R on the support 11 were 150 nm and 77 nm, respectively. By this dry etching process, a blue pixel 20B, a red pixel 20R, and a green pixel region formation 39 were obtained.

  Next, removal of the resist pattern 43 and baking were performed in the same manner as when the resist pattern 34 was removed.

  Next, the green light curable composition “SG-5000L” (manufactured by Fuji Film Electronics Materials Co., Ltd.) having a film thickness of 0.60 μm is formed so as to cover the surface of the support 11 on which the green pixel region formation 39 and the like are formed. After forming the coating film, a green layer 33G was formed by performing a baking process at 100 ° C. for 2 minutes using a hot plate.

Subsequently, the green layer 33G was subjected to pattern exposure, development processing, rinsing processing, drying processing, and the like under basically the same conditions as in the red pattern forming step 24. However, the exposure amount at the time of pattern exposure was changed to 200 mJ / cm ² . As described above, the green pixel 20G is formed on the green pixel region formation 39. The green pixels 20G were arranged in a checkered pattern so as to be embedded in the green pixel region formation 39, and each was formed into a square of 1.2 μm square. Moreover, the surface of each coloring pixel 20R, 20G, 20B was formed flat. That is, each surface was the same height as the support 11.

[Example 2]
Example 2 was prepared under the following conditions. First, in addition to the blue thermosetting composition described above, a red thermosetting composition and a green thermosetting composition were prepared.

<Red thermosetting composition>
First, the following red pigment dispersion was prepared.
-"Pigment Red 254" 80 parts by mass-"Pigment Yellow 139" 20 parts by mass-Dispersant EDAPLAN472 (manufactured by Enomoto Kasei Co., Ltd.) 30 parts by mass-Benzyl methacrylate / glycidyl methacrylate copolymer 10 parts by mass PGMEA 700 parts by mass or less, and the same treatment as that for preparing the blue pigment dispersion was performed to prepare a red pigment dispersion.

Next, a non-photosensitive coloring composition, that is, a red thermosetting composition was prepared by further adding a thermosetting resin to the red pigment dispersion.
EHPE-3150 0.5 part by mass (based on the red pigment dispersion)
Furthermore, PGMEA was added to the red pigment dispersion and the thermosetting resin, and the solid content of the composition was diluted to 15.0%.

<Green thermosetting composition>
First, the following green pigment dispersion was prepared.
-"Pigment Green 36" 90 parts by mass-"Pigment Green 7" 25 parts by mass-"Pigment Yellow 139" 40 parts by mass-Dispersant PALDDED151 (manufactured by Enomoto Chemical Co., Ltd.) 20 parts by mass Glycidyl methacrylate copolymer 10 parts by mass / PGMEA 630 parts by mass or less The same treatment as in the preparation of the blue pigment dispersion was performed to prepare a green pigment dispersion.

Next, a non-photosensitive coloring composition, that is, a green thermosetting composition was prepared by further adding a thermosetting resin to the green pigment dispersion.
EHPE-3150 0.8 part by mass (based on the green pigment dispersion)
Furthermore, PGMEA was added to the green pigment dispersion and the thermosetting resin, and the solid content of the composition was diluted to 13.0%.

  Example 2 was formed under the following conditions using each color thermosetting composition.

<Blue pattern formation process>
A blue pattern 27B was formed on the support 11 under basically the same conditions as in Example 1. However, the film thickness of the coating film of the blue layer 33B was changed to 0.55 μm, and the blue layer 33B after post-baking became 0.5 μm. Further, the baking temperature after pattern exposure was changed to 90 ° C. Further, among the dry etching conditions of the first embodiment, the etching time of the second stage was changed to 20 seconds, the overetching time was changed to (75 + 20) × 0.2 = 17 seconds, and the total etching time was changed to 114 seconds. The amount of scraping of the blue pattern 27B in the first stage etching was 438 nm (80% etching amount), and the thickness of the remaining film of the blue layer 33B was about 115 nm.

<Red pattern formation process>
Next, the red layer 33R was formed on the support 11 by forming and heating a 0.60 μm-thick coating film made of a red thermosetting composition by the same method as that for forming the blue layer 33B. .

  Next, the surface of the red layer 33R was polished with a slurry semisparse 25 diluted solution (stock solution: pure water = 1: 19) using a polishing (CMP) apparatus (BC-15 manufactured by AMT). At this time, the polishing treatment was performed under the conditions of slurry dilution liquid flow rate: 300 ml / min, wafer pressure: 1.2 psi, retainer ring pressure: 1.5 psi, polishing PAD rotation speed 50 rpm, and wafer rotation speed 50 rpm.

  With this polishing process, the polishing time required for exposing the blue pattern 27B was 25 seconds. The over polishing rate was set to 20%, and the actual polishing time was set to 25 seconds × 1.2 = 30 seconds. As a result, a red pattern 27 </ b> R having the same shape as that of the first example was formed on the support 11. The film thickness of the blue and red patterns 27B and 27R was 0.525 μm.

<Green pixel formation process>
Basically, the resist pattern forming process, the dry etching process, and the photoresist removing process were performed under the same conditions as in the first embodiment, and the blue pixel 20B, the red pixel 20R, and the green pixel forming region 39 were formed. However, the etching time of the first stage of the dry etching process was changed to 60 seconds, the etching time of the second stage was changed to 25 seconds, the overetching time was changed to 17 seconds, and the total etching time was changed to 102 seconds.

  Next, similarly to the formation of the blue layer 33 </ b> B, a green film 33 </ b> G was formed on the support 11 by forming and heating a 0.60 μm thick coating film made of a green thermosetting composition. Then, the surface of the green layer 33G was polished under the same conditions as those for the polishing process of the red layer 33R described above to form a green pixel 20G having the same shape as the first example. The film thickness of each colored pixel 20R, 20G, 20B was 0.50 μm.

[Example 3]
Example 3 was formed according to the following procedure using each color thermosetting composition described above.

<Blue pattern formation process>
After forming the blue layer 33B on the support 11 under basically the same conditions as in the first example, a thermosetting composition “1TS-54S-300A” (manufactured by Rasa Industrial Co., Ltd.) is formed on the blue layer 33B. ) Was applied with a spin coater so as to have a film thickness of 30 nm, and then cured by performing a heat treatment at 220 ° C. for 10 minutes to form the entire surface stopper layer 62.

  Thereafter, a resist pattern forming process, a dry etching process, and a photoresist removing process were performed in the same manner as in the first embodiment. The first stage etching time of the dry etching process is 78 seconds, the second stage etching time is 11 seconds, the etching time is 78 + 11 = 89 seconds, the overetching time is 89 × 0.2≈18 seconds, and the total etching time is 89 + 18. = Performed under the same conditions as in the first example except that the time was changed to 107 seconds. The amount of scraping in the first stage etching was 438 nm (87% etching amount), and the etching time for the entire surface stopper layer 62: about 3 seconds was required, so that there was a remaining film of about 62 nm. .

  Thus, the blue pattern 27B was formed on the support 11, and the stopper pattern layer 62a was formed on the surface thereof. The LINE & SPACE size of the blue pattern 27B is the same as that in the first embodiment.

<Red pattern formation process>
A red pattern 27R was formed under the same conditions as in Example 2.

<Green pixel formation process>
Basically, under the same conditions as in Example 2, a resist pattern forming process, a dry etching process, a photoresist removing process, a green layer forming process, and a polishing process were performed to form a green pixel 20G. However, the etching time of the first stage of the dry etching process was changed to 63 seconds, the etching time of the second stage was changed to 25 seconds, the overetching time was changed to 18 seconds, and the total etching time was changed to 106 seconds. The thickness of each colored pixel 20R, 20G, 20B (the blue pixel 20B includes the stopper layer 57) was 0.530 μm.

[Example 4]
Example 4 was formed according to the following procedure using each color thermosetting composition described above. Each process was performed under the same conditions as in Example 2 until the green layer forming step 51. And the etch-back process (flattening process) of the following conditions was performed. That is, RF power: 600 W, antenna bias: 100 W, wafer bias: 250 W, chamber internal pressure: 2.0 Pa, substrate temperature: 50 ° C., mixed by dry etching apparatus (U-621, manufactured by Hitachi High-Technologies Corporation) The gas type and flow rate of the gas were set to N ₂ : 500 mL / min. , Ar: 500 mL / min. (N ₂ / Ar = 1/1) was performed until the blue pixel 20B (red pixel 20R) was exposed.

  At this time, the etching rate of the green layer 33G was 150 nm / min, and it took 40 seconds (time to remove the green layer 33G) to expose the blue pixel 20B. Etching time was obtained by adding 4 seconds of overetching to this. As a result, the etching time was 40 seconds, the over-etching time was 4 seconds, and the total etching time was set to 40 + 4 = 44 seconds. The color pixels 20R, 20G, and 20B having the same shape as that of the second embodiment are formed. The film thickness of each colored pixel 20R, 20G, 20B was 0.50 μm.

  As described above, when forming Examples 1 to 4, the blue pixel 20B (blue pattern 27B) has a poor adhesion (peeling), and the blue pixel 20B is formed after removing the photoresist (after removing the resist pattern). However, peeling did not occur at all. Thereby, it was confirmed that the adhesiveness of the blue pixel 20B was ensured. In addition, after the photoresist removal step 31 was completed, no etching damage of the support 11 was confirmed.

  In the first to fourth embodiments, unlike a color filter formed by a conventional photolithography method, each color is formed in a blank area where no colored pixel is formed (see FIG. 32A) or in the vicinity of the boundary between the colored pixels. It was confirmed that the formation of a depression (see FIG. 32B) in which the pixel film thickness is reduced is suppressed. From this result, it was confirmed that the pattern formation limit was improved and a fine and thin pattern could be formed.

  Further, when the rectangularity of each colored pixel in Examples 1 to 4 was confirmed with an electron microscope (SEM), the color filter formed by a conventional method for forming an isolated pattern (including a photolithography method and a dry etching method) was used. It was confirmed that the roundness of the isolated pattern (pixel) corner was much smaller than that of the colored pixel, and the rectangularity of the colored pixel was improved. As a result, it was confirmed that the rectangularity of each colored pixel is improved as compared with the prior art by reducing the step of directly forming an isolated pattern as in the present invention.

It is sectional drawing of a solid-state image sensor and a color filter. It is a flowchart which shows the color filter manufacturing process of 1st Embodiment. It is explanatory drawing for demonstrating the blue layer formation process which comprises a blue pattern formation process. It is explanatory drawing for demonstrating the resist pattern formation process which comprises the process. It is explanatory drawing for demonstrating the dry etching process which comprises the process. It is explanatory drawing for demonstrating the photoresist removal process which comprises the process. It is explanatory drawing for demonstrating the red layer formation process of a red pattern formation process. It is explanatory drawing for demonstrating the exposure and image development process which processes the process. It is explanatory drawing for demonstrating the resist pattern formation process of a green pixel formation process. It is explanatory drawing for demonstrating the dry etching process which comprises the process. It is explanatory drawing for demonstrating the photoresist removal process which comprises the process. It is explanatory drawing for demonstrating the green layer formation process which comprises the process. It is explanatory drawing for demonstrating the exposure and image development process which comprises the process. It is a flowchart which shows the color filter manufacturing process of 2nd Embodiment. It is explanatory drawing for demonstrating the planarization process process of other embodiment in the red pattern formation process of the process. It is sectional drawing of the solid-state image sensor and color filter of 3rd Embodiment. It is a flowchart which shows the color filter manufacturing process of 3rd Embodiment. It is explanatory drawing for demonstrating the blue layer formation process and stopper layer formation process which comprise the blue pattern formation process of 3rd Embodiment. It is explanatory drawing for demonstrating the resist pattern formation process which comprises the process. It is explanatory drawing for demonstrating the dry etching process which comprises the process. It is explanatory drawing for demonstrating the photoresist removal process which comprises the process. It is explanatory drawing for demonstrating the red layer formation process which comprises the red pattern formation process of 3rd Embodiment. It is explanatory drawing for demonstrating the planarization process process which comprises the process. It is explanatory drawing for demonstrating the resist pattern formation process of the green pixel formation process of 3rd Embodiment. It is explanatory drawing for demonstrating the dry etching process which comprises the process. It is explanatory drawing for demonstrating the photoresist removal process which comprises the process. It is explanatory drawing for demonstrating the green layer formation process which comprises the process. It is explanatory drawing for demonstrating the planarization process process which comprises the process. It is a flowchart which shows the color filter manufacturing process of other embodiment which patterns a red layer by the dry etching method, and forms a red pattern. It is explanatory drawing for demonstrating the red pattern formation process of the process. It is a flowchart which shows the color filter manufacturing process of other embodiment which patterns a green layer by the dry etching method, and forms a green pixel. It is explanatory drawing for demonstrating the conventional color filter formed by the photolitho method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,47 Solid imaging device 11 Support body 13,56 Color filter 20B Blue pixel 20R Red pixel 20G Green pixel 22,46,55 Color filter manufacturing process 27B Blue pattern 27R Red pattern 33B Blue layer 33R Red layer 33G Green layer 57 Stopper layer

Claims (15)

In a color filter manufacturing method for manufacturing a color filter formed by two-dimensionally arranging colored pixels of a plurality of colors on a support,
A first color pattern forming step of forming a first color pattern of a first color stripe containing at least a blue pigment on the support;
A second color pattern forming step of forming a second color pattern in a stripe shape of the second color so as to fill a gap between the first color patterns on the support;
The first color pattern and the second color pattern are patterned by a dry etching method to form a first color pixel and a second color pixel on the support, and a third color pixel for forming a third color pixel. A patterning step for forming a three-color pixel formation region;
A color filter manufacturing method comprising: a third color pixel forming step of forming the third color pixel in the third color pixel formation region.   The method for manufacturing a color filter according to claim 1, wherein the first color pattern includes a violet pigment. The first color pattern forming step includes
A first colored layer forming step of forming a first colored layer comprising a colored thermosetting composition of the first color on the support;
Forming a first resist pattern corresponding to the first color pattern on the first colored layer using a photoresist; and
3. The color filter according to claim 1, further comprising: a first dry etching step in which the first color pattern is formed by dry etching the first color layer using the first resist pattern as a mask. 4. Manufacturing method. The second color pattern forming step includes
A second colored layer forming step of forming a second colored layer composed of a colored photocurable composition of the second color on the support on which the first colored pattern is formed;
4. The color according to claim 1, further comprising: a second color layer exposure / development step for forming the second color pattern by pattern exposure / development of the second color layer. 5. A method for manufacturing a filter. The second color pattern forming step includes
A second colored layer forming step of forming a second colored layer comprising a colored thermosetting composition of the second color on the support on which the first colored pattern is formed;
A second resist pattern forming step of forming a second resist pattern corresponding to the second color pattern using a photoresist on the second color coloring layer;
4. The method according to claim 1, further comprising: a second dry etching step in which the second color pattern is formed by dry etching the second color layer using the second resist pattern as a mask. 5. The manufacturing method of the color filter of description. The second color pattern forming step includes
A second colored layer forming step of forming a second colored layer comprising a colored thermosetting composition of the second color on the support on which the first colored pattern is formed;
The second color layer is flattened by applying a flattening process to the surface of the second color layer until the second color layer is removed from the first color pattern. A method for manufacturing a color filter according to any one of claims 1 to 3, further comprising a processing step. The third color pattern forming step includes:
Forming a third colored layer made of a colored photocurable composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel forming region are formed; A three-color colored layer forming step;
8. The color according to claim 1, further comprising: a third color layer exposure / development step of pattern exposure / development of the third color layer to form the third color pixel. A method for manufacturing a filter. The third color pixel forming step includes:
Forming a third color layer composed of a colored thermosetting composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel formation region are formed; A three-color colored layer forming step;
A third resist pattern forming step of forming a third resist pattern corresponding to the third color pixel formation region on the third color coloring layer;
8. A third dry etching step of forming the third color pixel by dry etching the third color colored layer using the third resist pattern as a mask. 8. The manufacturing method of the color filter of description. The third color pixel forming step includes:
Forming a third color layer composed of a colored thermosetting composition of a third color on a support on which the first color pixel, the second color pixel, and the third color pixel formation region are formed; A three-color colored layer forming step;
The surface of the third color layer is flattened to form the third color pixel until the third color layer is removed from the first color pixel and the second color pixel. The method for producing a color filter according to any one of claims 1 to 7, further comprising a three-color colored layer flattening treatment step.   10. The method for manufacturing a color filter according to claim 6, wherein the planarization process is performed by at least one of an etch back process and a polishing process. When the planarization process is performed by the polishing process,
The method for producing a color filter according to claim 10, wherein after the polishing treatment, a water washing step of washing the surface to be polished and a dehydration treatment step of dehydrating the surface to be polished after the water washing step are performed. Before the first resist pattern forming step, it has a stopper layer forming step of forming a transparent flattening stopper layer on the first colored layer,
The first resist pattern forming step forms the first resist pattern on the stopper layer,
The said 1st dry etching process uses the said 1st resist pattern, and dry-etches the said stopper layer in the stripe form corresponding to the said 1st color pattern, The one of Claim 3 thru | or 11 characterized by the above-mentioned. Manufacturing method of color filter.   The method for producing a color filter according to claim 12, wherein in the second color coloring layer flattening step, the surface of the second color coloring layer is flattened until the stopper layer is exposed.   14. The color filter manufacturing method according to claim 12, wherein in the third color layer flattening step, the surface of the third color layer is flattened until the stopper layer is exposed. Method.   15. The method of manufacturing a color filter according to claim 1, wherein the first color pattern and the second color pattern are formed such that adjacent patterns touch each other on the surface.

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