JPH0257285B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a color filter, and more particularly to a color filter for fine color separation in color image pickup devices, color sensors, color displays, and the like. As a color filter, a dyed color filter is known, in which a mordant layer made of a hydrophilic polymer material such as gelatin, casein, grue, or polyvinyl alcohol is provided on a substrate, and the mordant layer is dyed with a dye to form a colored layer. ing. Many dyes can be used in this dyeing method, and it is relatively easy to meet the spectral characteristics required for the filter. It also has the drawback of poor yields due to the complicated process of providing an interlayer for resist dyeing for each color. Furthermore, it has a relatively low heat resistance temperature of about 150 to 160°C, making it difficult to use in processes that require thermal treatment. On the other hand, a vapor deposition method is known in which a thin film of dye or pigment is formed by a vapor deposition method such as vapor deposition (Japanese Patent Application Laid-open No. 146406/1984, etc.). According to this method, a colored layer can be formed from the dye itself, so it can be made thinner than the dyeing method, and it is also easier to control as it is a non-aqueous process. It also has the feature of good heat resistance. However, it has not been widely used until now because it is not easy to select a usable dye suitable for vapor deposition.
When looking at color filters from the perspective of dyes, dyes for color filters are required to have the following properties. First of all, it must have appropriate spectral characteristics as a filter. On the other hand, from the viewpoint of the manufacturing method, even if the spectral characteristics are good, dyes lack manufacturing stability or require special processing steps, leading to a decrease in yield and ultimately making them unsuitable for color filters. Therefore, as a dye for color filters, it is necessary to select an optimal dye that is well-balanced in terms of both spectral characteristics and manufacturing. In particular, the vapor deposition method has strong manufacturing constraints such as being heat resistant, easily evaporated, and resistant to solvent treatment in the photolithography process, although it has various advantages over the dyeing method. First, vapor-deposited color filters were not widespread. By the way, the characteristics required of the dye used in vapor-deposited filters are that it can be vapor-deposited, that the resist after vapor-deposition can withstand solvents and heat treatment in photolithography, and that it has well-balanced spectral characteristics as a filter. However, phthalocyanine dyes are examples of dyes that relatively satisfy these characteristics. Since the basic phthalocyanine ring of phthalocyanine dyes is extremely stable both chemically and thermally, they are excellent in vapor deposition methods and solvent resistance. However, in terms of spectral characteristics, many phthalocyanine dyes exhibit blue or cyan color characteristics. Depending on the central metal or substituent, it may exhibit characteristics close to green, but as it generally leans toward the blue side, it is not sufficient to be viewed strictly as green. The main object of the present invention is therefore to provide a vapor-deposited color filter that takes advantage of the excellent vapor deposition method and solvent resistance of these phthalocyanines and compensates for their disadvantageous spectral properties. The color filter according to the present invention is a green pigment layer formed by vapor-depositing a lead phthalocyanine dye or a copper phthalocyanine dye and an anthraquinone dye, and is formed through the formation of a resist pattern, the vapor deposition, and the removal of the resist pattern with a solvent. It is characterized by having a patterned green pigment layer. That is, in the present invention, by using an anthraquinone-based yellow dye in addition to a phthalocyanine-based dye in the green dye layer, the blue spectral component of the phthalocyanine dye is cut out, and a colored layer having excellent green spectral properties is formed. It is something. The dye used for color correction of phthalocyanine dyes must be a yellow dye with sharp rise characteristics. Furthermore, since it is formed by a vapor deposition method, it needs to have vapor deposition properties and solvent resistance comparable to phthalocyanine dyes, and the anthraquinone yellow dye used in the present invention satisfies all of these properties. In combination with a phthalocyanine dye, it is possible to form an excellent vapor-deposited green colored layer. The anthraquinone dye used in the present invention refers to anthraquinone derivatives and similar polycyclic quinones. Anthraquinone dyes are thermally stable, do not decompose at high temperatures, and easily evaporate when the temperature exceeds a certain level, making them extremely suitable for forming dye thin films by vapor deposition. be. The thin film of anthraquinone dye formed by vapor deposition is not a loose film that is often seen in organic films, but is extremely dense and adheres strongly to the surface of inorganic materials such as glass, and has excellent physical properties as a vapor deposited film. have. On the other hand, this deposited film has excellent resistance to organic solvents. That is, it hardly dissolves in good solvents such as ketones, esters, ether alcohols, and halogen solvents as well as poor solvents such as alcohols, and does not cause any change in spectral characteristics. Therefore, there is no problem at all when resist is applied and developed to the dye layer, and the dye layer can be easily microfabricated, making it extremely suitable for manufacturing fine color filters, etc. . An example of the structure of a typical anthraquinone yellow pigment is shown below. However, the dyes that can form the dye layer of the color filter of the present invention are not necessarily limited to these. Examples of commercially available anthraquinone dyes are listed below using trade names. Chromophthal Yellow A2R (manufactured by Ciba Geigy) CINo.70600 Heliophthalst Yellow E3R (manufactured by Bayer) Palyogen Yellow L1560 (manufactured by BASF) CINo.68420 Kayaset Yellow E-R (manufactured by Nippon Kayaku) CINo.65049 Chromophthal Yellow AGR (manufactured by Ciba Geigy) Biplast Yellow E2G (manufactured by Bayer) Nihonthrene Yellow GCN (manufactured by Sumitomo Chemical) CINo.67300 Mikethrene Yellow GK (manufactured by Mitsui Toatsu) CINo.61725 Indanthrene Pretaining Yellow GOK (manufactured by Hoechst) CINo.59100 Anthrazole Yellow V (manufactured by Hoechst) CINo.60531 Mikethrene Soluble Yellow 12G (manufactured by Mitsui Toatsu) CINo.60605 Mikethrene Yellow GF (manufactured by Mitsui Toatsu) CINo.66510 Nihonthrene Yellow GCF (manufactured by Sumitomo Chemical) CINo.65430 Indanthrene Yellow 3G (manufactured by Bayer) CINo.65405 Nihonthrene Yellow 4GL (manufactured by Sumitomo Chemical) Indanthrene Yellow 5GK (manufactured by Bayer) CINo.65410 Paranthrene Yellow PGA (manufactured by BASF) CINo.68400 Cibanon Yellow 2G (manufactured by Ciba Geigy) Indanthrene Yellow F2GC (manufactured by Hoechst) Anthra Sol Yellow IGG (Manufactured by Hoechst) Indanthrene Yellow 5GF (Manufactured by BASF) Mikethrene Yellow 3GL (Manufactured by Mitsui Toatsu) Indanthrene Yellow LGF (Manufactured by BASF) Monolite Yellow FR (Manufactured by ICI) Kayaset Yellow E-AR (Japanese) Pharmaceutical products) As the phthalocyanine dye, lead phthalocyanine dye or copper phthalocyanine dye is used. In order to form a green pigment layer in combination with an anthraquinone pigment, a phthalocyanine pigment having a high transmittance on the green side is desirable. The green colored layer is generally formed by sequentially depositing a phthalocyanine dye and an anthraquinone dye, but simultaneous vapor deposition may also be used. Each film thickness or deposition amount is controlled according to desired spectral characteristics. Usually, a film thickness of 500 to 10,000 Å is appropriate for each film. Next, a method for forming these patterned dye layers will be described. Patterning techniques for vapor-deposited dye layers include dry etching and lift-off.
In the dry etching method, a resist pattern is created on a dye layer, and using this as a mask, a dye pattern is formed by plasma or ion etching. (Unexamined Japanese Patent Publication No. 58-34961, etc.). This method does not require the formation of an intermediate layer as in the dyeing method, but instead a resist mask remains on the dye pattern. Furthermore, since it is extremely difficult to remove this mask without causing any damage to the dye layer, the result is a two-layer structure in which a substantially optically unnecessary resist mask is laminated on the dye layer. In addition, the formation of a yellow-like green pigment layer by the lift-off method involves forming a pattern at the bottom of the pigment layer to be removed using a soluble substance, mainly a resist, and then depositing a vapor-deposited pigment layer thereon. This is carried out by dissolving or peeling off the resist pattern, and the dye layer thereon can be physically removed without any direct effect on the dye layer. The resist used in the dye layer lift-off method may be either a negative type or a positive type, as long as it can be dissolved later. However, in the case of a negative type, crosslinking generally progresses when exposed to radiation, and a solvent with strong dissolving power is required to dissolve it. Therefore, it is not preferable because it tends to damage or dissolve the dye layer. In this respect, positive-type resists become soluble when the entire surface is irradiated with radiation after forming a resist pattern, so a solvent that dissolves the dye less easily can be selected compared to negative-type resists, making it suitable for lift-off.
Furthermore, positive resists have a wide variety of resin components, and various solvents are used for coating and developing them. It is desirable to select a positive resist that can use a solvent that has less action on the dye, and a preferred example is a positive resist that is based on a fluorine-containing methacrylate having the structure shown below as a polymerized unit. This resist dissolves well in not only good solvents that have a high dissolving power such as esters, aromatics, and halogenated hydrocarbons, but also poor solvents that have a low dissolving power such as alcohols, so it does not form a dye film. This is because a solvent with less influence can be used. In this way, as a resist, FPM210,
Examples include FBM110 and FBM120 (both trade names manufactured by Daikin Industries). Here, R ₁ and R ₅ are hydrogen or an alkyl group,
R ₃ is an alkyl group having at least one fluorine bonded to each carbon. Typical examples include:

[Table] As other resists, various products commercially available under the following trade names can be used as appropriate. AZ series: 111, 119A, 120, 340, 1350B,
1350J, 1370, 1375, 1450, 1450J, 1470,
1475, 2400, 2415, 2430 (manufactured by Sibley) Waycoat Positive LSI Resist (195, 295,
395) Waycoat HPR Positive Resist (104, 106) (Manufactured by Hunt) Kodak Micro Positive Resist (Manufactured by Kodatsu) Isofine Positive Resist (Manufactured by Micro Image Technology) PC129, 129SF (Manufactured by Polychrome) OFPR 77, 78, 800 OEBR 1000, 1010, 1030 ODUR 100, 1001, 1010, 1013, 1014 (manufactured by Tokyo Ohka) EBR 1, 9 (manufactured by Toray Industries) FMR E100, E101 (manufactured by Fuji Pharmaceutical Co., Ltd.) Patterned coloring is achieved through the above patterning process. After the layer is formed, it is desirable to provide a protective film over the colored layer. This is to prevent the adhesion of dust and the occurrence of scratches, and to protect the colored layer from various environmental conditions. Various commonly known methods can be used to form the protective film. Organic resins such as rubber resins such as reduced rubber, polyurethane, polycarbonate, silicone, acrylic polyparaxylylene, Si ₃ N ₄ , SiO,
An inorganic film of Al ₂ O ₃ , Ta ₂ O ₃ or the like can be formed by a coating method such as a spin cord, a coating method, a roll coater, or by vapor deposition. It is also possible to use various photosensitive resins, such as various resists. The substrate used in the present invention is not particularly limited as long as dye deposition is possible. For example, the following can be specifically used. It is also possible to integrally form glass plates, optical resins, resin films such as gelatin, polyvinyl alcohol, hydroxyethyl cellulose, methyl methacrylate, polyester, petitral, polyamide, etc., and patterned colored layers with those applied as color filters. be. Examples of substrates in this case include cathode ray tube display surface, image pickup tube light receiving surface, OCD, BBD,
Examples include wafers on which solid-state imaging devices such as CID are formed, contact type image sensors using thin film semiconductors, liquid crystal display surfaces, and photoreceptors for color electrophotography. If it is necessary to increase the contact between the deposited dye layer and the underlying substrate, such as glass, apply a thin layer of polyurethane resin, polycarbonate resin, silane coupling agent, etc. to the glass substrate before applying the deposited film. It is effective when formed. A typical pattern creation process of the present invention will be explained below with reference to the drawings. A positive resist is spin-coated onto a desired substrate using a spinner. After drying, prebaking is performed under appropriate temperature conditions. Then, it is exposed to light or electron beam having resist sensitivity in a predetermined pattern shape and developed. If necessary, pretreatment for the purpose of alleviating strain on the resist film before development and rinsing treatment for suppressing swelling of the resist film after development are performed. If the remaining resist film and residue, so-called scum, cannot be removed even by development, they can be removed by plasma ashing. Through the above steps, the resist pattern 2 shown in FIG. 1 is formed on the substrate 1. Then the second
As shown in the figure, the entire surface is irradiated with a resist-sensitive light or electron beam. This is to facilitate the subsequent dissolution and removal of the resist pattern by cutting and decomposing the main chain of the resist, but it can also be omitted. If it is omitted, it is necessary to use a solvent with stronger solubility. Then, as shown in FIG. 3, a dye layer 3 is formed on the resist pattern by vacuum evaporation. When layering phthalocyanine dyes and anthraquinone dyes, vapor deposition is repeated. The thickness of the dye layer is determined depending on the desired spectral characteristics, but is usually about 500 to 10,000 Å. Next, in order to remove the resist pattern under the dye layer, the resist pattern is immersed in a solvent that dissolves or peels only the resist pattern from the substrate without dissolving the dye and without damaging the spectral characteristics. Removal of the resist pattern simultaneously removes the dye layer thereon, and to assist in this removal, it is also effective to apply ultrasonic energy during dipping. In this way, a patterned colored layer 4 is formed as shown in FIG. When forming dyes on the same substrate, the above steps may be repeated while shifting the position of the resist pattern according to different patterns. By repeating these steps as many times as there are different colors, it is possible to produce a patterned colored layer 4, 5, and 6 having three colors as shown in FIG. 5, for example. Then, a desired resin layer 7 is applied as a protective layer on the patterned colored layer to complete the color filter. (Figure 6) Example 1 Positive resist FPM210 (product name: manufactured by Daikin Industries) by spinner coating on a glass substrate
was applied to a film thickness of 0.6 μm. After prebaking at 180° C. for 30 minutes, stripe-shaped exposure was performed using deep ultraviolet light, and treatment was performed using a dedicated pretreatment solution, developer, and rinse solution to form a resist pattern.
Next, the entire surface of this pattern was irradiated with deep ultraviolet light to make it soluble in a developer. Next, the glass substrate on which the resist pattern was formed and the copper phthalocyanine packed in the molybdenum vapor deposition boat were placed in a vacuum vapor deposition machine and evacuated. Deposition boat at vacuum level 15 ^-5 to ^{10 -6} torr 450 to 550
℃ to deposit copper phthalocyanine to a thickness of about 1300 Å. Using a similar method, chromophthal yellow AGR (trade name: manufactured by Ciba Geigy) as an anthraquinone dye was vapor-deposited to a thickness of about 4000 Å. Subsequently, the glass substrate on which the vapor deposition was completed was immersed and stirred in the above-mentioned special developer to dissolve the resist pattern and remove unnecessary portions of the vapor deposited film, thereby making it possible to obtain a colored layer with green stripes. The spectral characteristics of the green colored layer of the obtained color filter of the present invention are shown in curve 10 in FIG.
From this spectral curve 10, chromophthal yellow
The spectral characteristics of AGR (curve 9) cut out the blue component in the spectral characteristics of copper phthalocyanine (curve 8), and the excellent green characteristics of the color filter of the present invention, which utilizes the green component, are reproduced by the color filter of the present invention. It was recognized that the pigment layer had a pigment layer. Examples 2 to 4 A green colored layer of a color filter of the present invention was formed in the same manner as in Example 1, except that the following dyes were used in combination as phthalocyanine dyes and anthraquinone dyes. In each case, patterned green colored layers with improved spectral characteristics were obtained as in Example 1.

【table】

【table】 [Brief explanation of the drawing]

1 to 6 are process explanatory diagrams of the method for manufacturing a color filter according to the present invention, in which FIG. 1 is a resist pattern forming process diagram, FIG. 2 is an exposure process diagram,
Figure 3 is a diagram showing the formation process of the dye layer, Figure 4 is a diagram showing the patterned colored layer formation process, Figure 5 is a diagram showing one embodiment of the three colored colored layers to be manufactured, and Figure 6 is the protection It is a figure showing a layer formation process. FIG. 7 shows a graph of spectral transmittance. 1...Substrate, 2...Resist pattern, 3...
Dye layer, 4, 5 and 6...patterned dye layer,
7...Resin layer.

Claims (1)

[Claims] 1 Formation of a resist pattern with a green dye layer formed by vapor-depositing lead phthalocyanine dye or copper phthalocyanine dye and anthraquinone dye;
A color filter comprising a patterned green dye layer formed through the vapor deposition and removal of the resist pattern using a solvent.