JPS6084505A - Manufacture of color filter - Google Patents

Abstract

PURPOSE:To prevent lack of density, etc., by forming a resist mask, introducing an O2-contg. gas, and subjecting the mask to discharge before forming a dye layer through the vapor deposition method. CONSTITUTION:A photoresist is laminated on a base 1 made of glass or the like, exposed to UV light or the like through a pattern mask, and then, the exposed or unexposed parts are eluted with a developing soln. The base 1 on which an undermask is formed is set on a base holder 3 in a plasma vacuum vapor deposition vessel 2, and the vessel 2 is evacuated through an evacuation pipe 4. A gaseous Ar or the like contg. O2 is introduced through the pipe 4, voltage is impressed to the discharge electrode 7 to cause plasma for descumming the base 1. Vapor deposition to the base 1 is executed by again evacuating the vessel 2, opening a shutter 6, and heating a vapor deposition dye source 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a color filter, and more particularly to a method for manufacturing a color filter suitable for various color imaging devices and fine color separation filters for color displays.

Conventionally, as a method for producing a color filter, a method of forming a dye layer as a thin film of dye deposited by a vacuum vapor deposition method is known, for example, from Japanese Patent Application Laid-Open No. 146408/1983. According to such a vacuum evaporation method, a colored layer can be formed using the dye itself, so a mordant layer is not required when using a dyeing method, and the dye layer can be made extremely thin. have.

A dry etching method is widely used as a method for patterning the dye layer formed by such vapor deposition. In this method, as shown in, for example, Japanese Unexamined Patent Publication No. 58-341181, a pattern is formed using a resist on a dye layer, and then using this as a resist mask, the portions of the dye layer not covered with the resist are ionized. Generally, it is removed by etching or using plasma. However, in this method, it is not easy to select a resist that can be formed without damaging the dye layer and has good etching resistance for the first dye layer-L. Because the resist-y fabric remains,
This method has the disadvantage that the structure of the obtained color filter becomes complicated.

On the other hand, on the other hand, for example,
A pattern forming method called a lift-off method (or reverse etching method) is known from Japanese Patent Publication No. In this method, a pattern mask (hereinafter referred to as an undermask) is formed in advance on a substrate using a substance that can be dissolved and removed later, mainly a positive resist, and a colored layer is formed on the substrate and the undermask. Then, by removing the lower undermask from the substrate without directly acting on the colored layer, the unnecessary colored layer on the upper part is physically removed, and the desired pattern of the colored layer is formed. This is a method of forming on a substrate. According to this lift-off method, a colored layer pattern is formed by removing the undermask, so no resist mask remains in the resulting color filter, which has the advantage of achieving a simple configuration of only the colored layer. .

However, there are also problems with the method of forming color filters using a combination of lift-off method and vacuum evaporation method. That is, when forming an undermask using a resist on a substrate, residues of the resist for the undermask (hereinafter referred to as scum) may remain in unnecessary portions of the resist on the substrate. If a dye layer is formed by vapor deposition while this scum remains, the dye layer deposited on the scum will also be peeled off from the substrate when the undermask is lifted off, and this part will The transmission of white transmitted light causes appearance defects (hereinafter referred to as white spots) that cause a decrease in the optical performance of the color filter.

A possible method for preventing the occurrence of such white spots is to perform ashing using plasma to remove scum after forming an undermask. That is, after forming the undermask, the substrate is placed in a plasma generator, and ashing is performed using plasma to remove scum (hereinafter referred to as descum). After the descum is finished, the substrate is removed from the plasma generator and
In this method, the dye is placed in a vacuum evaporation device and the dye is evaporated.

However, when the above-described descum method is employed, separate apparatuses are required for performing descum and dye deposition.

2) Descum and dye deposition both need to be performed under high vacuum, so each device must be individually depressurized and returned to atmospheric pressure, which takes a long time and requires additional energy. becomes.

3) It is necessary to move and store the substrate between the descum equipment and the vacuum evaporation equipment, which takes time, and when the substrate is moved, dust etc. may adhere, which may cause white spots. there were.

These disadvantages have caused an increase in the manufacturing cost of color filters and a decrease in manufacturing yield.

The inventors of the present invention have conducted intensive studies on a method for manufacturing color filters using the lift-off method that solves the above-mentioned drawbacks.
It has been found that these problems can be solved at once by performing descum and dye deposition in the same vacuum chamber.

An object of the present invention is to provide a method for manufacturing a color filter that is inexpensive to manufacture and hardly causes defects such as white spots.

That is, the method for manufacturing a color filter of the present invention includes a step of forming a resist mask on a substrate, a step of forming a dye layer by vapor deposition on the substrate on which the resist mask is formed, and a step of forming a dye layer on the substrate on which the resist mask is formed. In the method for manufacturing a color filter in which a dye layer having a desired pattern is formed on a substrate, the method includes a step of removing the dye layer from the substrate after forming a resist mask and prior to forming the dye layer. Manufacture of a color filter characterized by introducing an oxygen-containing gas into a vacuum evaporation tank containing a substrate to generate an electric discharge, and then forming a dye layer on the substrate by an evaporation method in the tank. It's a method.

Hereinafter, the method for manufacturing a color filter according to the present invention will be explained in more detail.

First, a photoresist is layered on a substrate and exposed to ultraviolet light, deep ultraviolet light, X-rays, electron beams, etc. through a pattern mask. Various substrates can be used depending on the purpose of use, and although not particularly limited, specifically, the following substrates can be used. For example, gala, suba;
Examples include transparent members such as optical resin plates made of polymethyl methacrylate, polycyclohexyl methacrylate, polystyrene, polycarbonate, diethylene glycol carbonate, etc.; resin films made of gelatin, polyvinyl alcohol, hydroxyl ethyl cellulose, polyester, polybutyral, polyamide, etc. Also,
It is also possible to form the substrate integrally with a color filter to which the color filter is applied; examples of the substrate in this case include solid-state imaging devices such as CCD, BBD, and CID, display surfaces of cathode ray tubes, light-receiving surfaces of image pickup tubes, LCD display surface,
Examples include color electrophotographic photoreceptors. The photoresist may be a liquid type or a dry film type.

Next, by selectively dissolving exposed or unexposed portions of the exposed photoresist using a developer, a substrate on which an undermask is formed is obtained. When a positive type photoresist is used, the entire substrate on which the under mask is formed is exposed to ultraviolet light or the like to enable lift-off later.

The substrate on which the undermask thus obtained is then subjected to a discharge step and a dye deposition step in the same vacuum deposition tank, which are the characteristic steps of the method of the present invention. These steps will be explained below with reference to FIG. The apparatus shown in FIG. 1 is suitable for implementing the above steps of the present invention, and is specially equipped with a pipe for introducing oxygen gas and a discharge electrode within the vacuum evaporation apparatus (hereinafter referred to as (referred to as plasma vacuum evaporation equipment). The gas supply port of the pipe for introducing oxygen gas is preferably provided as close to the substrate as possible. This is to avoid gas containing impurities such as H2O generated from the substrate from staying near the substrate during the descum operation, and to ensure that as fresh oxygen plasma as possible is supplied near the substrate. . ' After mounting the substrate l on which the undermask has been formed on the substrate holder 3 in the plasma vacuum deposition tank 2, the exhaust pipe 4 is
10'S-104t inside the plasma vacuum deposition tank 2 through
Next, while continuing the exhaust through the exhaust pipe 4, the oxygen-containing gas is introduced from the oxygen gas introduction pipe 5, which has an opening directly above the substrate holder 3, to 10-2 to '5 torr. Introduce it to a certain degree of pressure. Thereafter, a high frequency, alternating current, or direct current voltage is applied to the discharge electrode 7 provided between the shutter 6 and the substrate holder 3 via the power source 8 to generate plasma in the plasma vacuum evaporation tank 2, and the substrate to be evaporated is heated. Perform descum of l. The descum is usually carried out for about 1 to 10 minutes, and after the descum is finished, the introduction of the oxygen-containing gas into the vacuum deposition tank 2 is stopped. After stopping the introduction of gas, the inside of the plasma vacuum deposition tank 2 is again evacuated to about 10' to 10'' tarr.Then, the shutter 6 is opened, the vapor deposition dye source 9 is heated, and vapor deposition is performed on the substrate l. .

The oxygen-containing gas used in the method of the present invention includes:
Argon, helium, honey, xenon, carbon dioxide, CF
4, a mixed gas of a catalyst and a gas such as C2F6, CHF3, CG14, and oxygen gas.

Further, dyes that can be applied to the method of the present invention include dyes or pigments that can be sublimated or vapor deposited, and typical examples include phthalocyanine pigments, isoindolinone pigments, polycyclic pigments, Examples include naphthol pigments, indathrene dyes, oil-soluble dyes, and disperse dyes.

If the undermask of the substrate on which the dye layer is formed in this manner is then removed by means such as dissolution in the same manner as the conventional lift-off method, the unnecessary vapor deposited layer on the undermask will also be removed at the same time. , a dye layer having a pattern of a desired shape can be obtained on the substrate.

Through the above steps, a patterned dye layer of one color is formed on the substrate, but by repeating these steps, a color filter having dye layers of multiple colors can also be manufactured.

According to the color filter manufacturing method of the present invention, descum and dye deposition are carried out in the same vacuum chamber, so the manufacturing cost is low and the color filter is free from defects such as white spots. can be manufactured.

Hereinafter, the method for manufacturing a color filter of the present invention will be explained in more detail based on Examples.

Example: Positive resist 0DUR101 was applied to transparent glass substrate-E.
3 (trade name, manufactured by Tokyo Ohka ■) with a spinner for 7000
It was applied to a film thickness of . This resist film was heated at 120°C for 2
After prebaking for 0 minutes, the exposed area was 1Ou x 20μ.
Exposure was performed for 180 seconds with far ultraviolet light 1 using a mask having a large number of rectangles of s. Next, the glass substrate on which this exposed resist was laminated was immersed for 3 minutes in a special developer for the 0DURIOIO series to develop the resist and form an undermask. Subsequently, the entire surface of the glass substrate on which the undermask was formed was exposed to deep ultraviolet light for 400 seconds to make the undermask soluble in a solvent.

Next, this glass substrate and the Nj-phthalocyanine packed in the No port were set in the plasma vacuum evaporation apparatus shown in Fig. 1, and after exhausting the inside of the apparatus to 10'5 toor, while continuing the exhaust through the exhaust pipe. Oxygen-containing gas was introduced from the oxygen gas introduction pipe to a pressure of about 10' torr. and 13.5 MHz to the discharge electrode,
A high frequency of 100 W was applied to generate oxygen gas plasma in the plasma vacuum deposition tank, and the substrate to be deposited fixed on the substrate holder was descumed for 2 minutes. After the descum was completed, the introduction of oxygen-containing gas into the vacuum deposition tank was stopped, and the tank was again evacuated to about 10' to 10' torr, and the Mo port was heated to 450 to 500°C and the shutter was opened. , 2 A dye film of Ni-phthalocyanine was deposited on the substrate to a thickness of 300 OA. The substrate that has been evaporated is taken out of the plasma vacuum evaporation equipment, and the undermask is removed by immersing and stirring in a special developer for the 0DURIOIO series.
At the same time, the unnecessary dye layer was also removed. In this way, many rectangular blue dye layers were formed on the glass substrate.

Next, on the glass substrate on which this blue dye layer has been formed, a positive resist is applied, prebaked, exposed to deep ultraviolet light through a mask, and developed in the same manner as the previous blue dye layer was formed. was performed to form an undermask. After exposing the entire surface of the substrate to deep ultraviolet light, this glass substrate was set in a plasma vacuum evaporation device, and descum was performed in the same manner as in the previous case. ) to 400-500℃ and
A dye layer was deposited to a thickness of 0.000 A. Next, the substrate was taken out from the vapor deposition apparatus and lift-off was performed to form a red dye layer in addition to the blue dye layer.

3. A yellow dye layer was formed by repeating the same steps. However, as the yellow pigment, Lionogen Yellow RX (manufactured by Toyo Ink ■) was used, heated to 400 to 500°C, and a pigment layer was deposited to a thickness of 3000A.

By repeating patterning of the dye three times in this manner, a color filter whose schematic cross-sectional view is shown in FIG. 2 was manufactured. When the obtained color filter was observed under a microscope, there were no appearance defects such as white spots.

Comparative Example Except that descum and dye deposition were carried out in separate apparatuses, other operations were the same as in the examples to produce blue, red, and
A color filter with a yellow dye pattern was produced. Compared to the previous example, the time required for manufacturing was approximately 20% longer. Furthermore, when color filters manufactured by this method were observed under a microscope, about 10% of the products (10 out of 100 samples had defects) had white spots with a size of 15 μm or more.

[Brief explanation of the drawing]

FIG. 1 shows a plasma vacuum deposition apparatus suitable for manufacturing the color filter of the present invention, and FIG. 2 is a schematic cross-sectional view of the color filter manufactured by the method of the present invention. ■ = Substrate 2: Plasma vacuum deposition tank 3: Substrate holder 4 = Exhaust pipe 5; Oxygen gas introduction pipe 6: Shutter 7 = Discharge electrode 8: Power supply 9: Vapor deposition dye source B: Blue dye layer R: Red dye layer Y : Yellow pigment layer patent applicant Canon Co., Ltd. 5 Figure 1 Section 2

Claims (1)

[Claims] A substrate comprising: forming a resist mask on a substrate; forming a dye layer by vapor deposition on the substrate on which the resist mask is formed; and removing the resist mask from the substrate. In a method for manufacturing a color filter in which a dye layer with a desired pattern is formed, after forming a resist mask and prior to forming a dye layer, oxygen is introduced into a vacuum evaporation tank containing the substrate. 1. A method for manufacturing a color filter, which comprises introducing a containing gas and performing discharge, and then forming a dye layer on a substrate by a vapor deposition method in the tank.