JPH1138221A - Tantalum-based black mask, color filter formed by using the same, and liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a black mask, color filter and liquid crystal display, which are easy to handle at the time of production. SOLUTION: This black mask has a first antireflection film 3a, which is formed on a transparent substrate 2 and consists of a tantalum compd. and a light shielding film 5, which is formed on the first antireflection film 3a, consists of metal tantalum and shields visible light. A second antireflection film 3b and a third antireflection film 3c consisting of the tantalum compds. of different compsns. may be interposed between the first antireflection film 3a and the light shielding film 5. The tantalum compds. contain at least one kind selected from the group consisting of a tantalum oxide, tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum nitrocarbide and tantalum oxynitrocarbide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a black mask,
The present invention relates to a color filter and a liquid crystal display.

[0002]

2. Description of the Related Art A color liquid crystal display of the STN type or the TFT type is provided with a color filter at a position facing a liquid crystal layer. The color filter has a colored resin separated by a black mask, and the characteristics of the black mask affect the visibility of the liquid crystal display. A conventional black mask is disclosed in JP-A-8-1793.
No. 01 publication.

[0003]

In a color filter used in a liquid crystal display, in order to improve the visibility of the panel, the light reflectance on the surface of a black mask, which is one of the components, and the color filter in the visible wavelength region are required. It is required to reduce the wavelength dependence of the reflectance (reduce the amplitude of the reflectance at each wavelength). In order to reduce the surface reflectance, a black mask formed by etching a multilayered chromium compound film and a metal chromium film is effective. However, when the chromium film is etched, a waste liquid containing chromium is generated. Since this waste liquid requires a special treatment method, its handling was difficult.

[0004] It is an object of the present invention to provide a black mask, a color filter and a liquid crystal display which are easy to handle during manufacture.

[0005]

In order to solve the above-mentioned problems, a black mask of the present invention is formed on a transparent substrate and has a first antireflection film made of a tantalum compound and a first antireflection film formed on the first antireflection film. And a light shielding film made of metal tantalum and shielding visible light. Tantalum is easier to handle than chromium, and the reflectance and the wavelength dependence of the reflectance of a black mask using the tantalum compound for the first antireflection film can be sufficiently reduced.

[0006] The black mask of the present invention may further include a second antireflection film interposed between the first antireflection film and the light shielding film and made of a tantalum compound having a composition different from that of the first antireflection film. .

[0007] The black mask of the present invention further comprises a third antireflection film interposed between the second antireflection film and the light shielding film and made of a tantalum compound having a different composition from the first and second antireflection films. It may be.

The tantalum compound includes tantalum oxide, tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum oxynitride, and tantalum oxynitride carbide.

A color filter according to the present invention comprises such a black mask, a transparent substrate having the black mask formed thereon, and a colored resin disposed in a plurality of openings of the black mask. This color filter separates the light transmitted through the colored resin because the black mask separates the colored resin disposed in the opening. Since the wavelength dependence of the reflectance and reflectance of the light emitted to the black mask through the transparent substrate is reduced, the ratio of the reflected light to the light transmitted through the colored resin can be reduced,
The visibility of light transmitted through the colored resin can be improved.

Further, the liquid crystal display according to the present invention comprises:
A first substrate having the color filter, a second substrate having a plurality of electrodes, and being sandwiched between the first and second substrates;
A liquid crystal layer whose orientation can be changed for each region facing the plurality of openings of the black mask by applying a predetermined potential to the electrode is provided.

In this liquid crystal display, by applying a predetermined potential to the electrodes, the orientation can be changed for each region of the liquid crystal layer facing the plurality of openings of the black mask in the liquid crystal layer. The amount of input light can be controlled for each opening of the black mask.
Since the colored resin is disposed in the opening of the black mask, it is possible to emit light of a wavelength component corresponding to the colored resin for each of the regions. The color of this liquid crystal display
Since the filter can improve the visibility of light transmitted through the colored resin, a clear image can be displayed on the liquid crystal display.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A black mask according to an embodiment of the present invention will be described below using a color filter having a black mask. The same elements will be denoted by the same reference symbols, without redundant description.

(First Embodiment) FIG. 1 is a perspective view showing a color filter 1 provided with a black mask BM. First, the black mask B according to the first embodiment
M will be described. The color filter 1 includes a transparent glass substrate 2 and first transparent glass substrates 2 sequentially deposited on the transparent glass substrate 2.
A black mask BM (black matrix) including the anti-reflection film 3a, the second anti-reflection film 3b, the third anti-reflection film 3c, and the light shielding film 5, an overcoat layer 6 formed on the black mask BM, and an overcoat A transparent electrode 7 formed on the layer 6. Further, a polarizing plate 8 is attached to the back side of the transparent glass substrate 2.

The first antireflection film 3a is made of tantalum oxide,
It contains at least one of the group consisting of tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum oxynitride, and tantalum oxynitride carbide, but may also contain a mixture thereof. That is, the tantalum oxide contained in the first antireflection film 3a is:
TaO ₂ , Ta ₂ O _{5 and the} like, the tantalum nitride contained in the first anti-reflection film 3a is TaN and the like, and the tantalum carbide contained in the first anti-reflection film 3a is TaC and the like.

The second antireflection film 3b is made of tantalum oxide,
It contains at least one of the group consisting of tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum oxynitride, and tantalum oxynitride carbide, but may also contain a mixture thereof. The composition of the second antireflection film 3b is different from the composition of the first antireflection film 3a, and the refractive index and absorption coefficient for visible light are set so as to prevent reflection by being combined with the first antireflection film 3a. Have been.

The third antireflection film 3c is made of tantalum oxide,
It contains at least one of the group consisting of tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum oxynitride, and tantalum oxynitride carbide, but may also contain a mixture thereof. The composition of the third anti-reflection film 3c is determined by the first and second anti-reflection films 3a,
Unlike the composition 3b, the refractive index and absorption coefficient for visible light are set so as to prevent reflection by being combined with the first and second antireflection films 3a and 3b.

First, second and third antireflection films 3a, 3
The thicknesses of b and 3c are 5 to 2 in order to reduce the reflected light.
It is preferably 00 nm, and from the viewpoint of reducing the reflected light and its wavelength dependence, it is preferably 5 to 60 nm.

The light shielding film 5 is made of metal tantalum,
It has a thickness of 00 nm and blocks visible light. The films 3a, 3b, 3c and 5 may contain some impurities so as not to affect the optical characteristics. Also,
The transparent electrode 7 is made of ITO (Indium-Tin-Oxide).

The above-described black mask BM having a four-layer structure of the first antireflection film 3a, the second antireflection film 3b, the third antireflection film 3c, and the light-shielding film 5 has a reflectance to visible light and a wavelength of the reflectance. Dependency can be reduced sufficiently.

FIG. 2 shows the color filter 1 shown in FIG.
It is XX arrow sectional drawing of. The black mask BM has a plurality of openings, and the three adjacent openings are filled with resins of different colors as optical filters. That is, the colored resin R is a resin colored red, is a resin containing a red pigment in the photoresist and is cured, and the colored resin G is a resin colored green, and The resist is a resin that contains a green pigment and is cured, and the colored resin B is a resin that is colored blue and is a resin that contains a blue pigment and is cured.

In the color filter 1, since the black mask BM separates the colored resins R, G, and B disposed in the openings, the color filter 1 separates light transmitted through the colored resins R, G, and B. Since the reflectance of the light irradiated to the black mask BM via the transparent substrate 2 and the wavelength dependence of the reflectance are sufficiently reduced, the ratio of the reflected light to the light transmitted through the colored resins R, G, and B is reduced. Colored resins R, G, B
The visibility of the light transmitted through can be improved.

Next, a method of manufacturing the color filter 1 according to the first embodiment will be described.

In order to manufacture the present color filter 1, first, a transparent glass substrate 2 transparent to visible light is prepared, and a first anti-reflection film 3a and a second anti-reflection film 3 are formed on the surface of the transparent substrate 2. The film 3b, the third antireflection film 3c, and the light shielding film 5 are sequentially deposited.

The first antireflection film 3a is formed using a reactive sputtering method. That is, after disposing the transparent substrate 2 in a chamber (not shown), a substrate containing tantalum metal is disposed as a target at a position facing the transparent substrate 2. Next, after the pressure in the chamber is reduced to the _first pressure P1 or less, an argon gas as an inert gas (rare gas) is introduced into the chamber, and a reaction gas (oxygen, nitrogen, and at least one of carbon dioxide, or combinations thereof) is introduced into the chamber, maintaining the pressure in the chamber to a second pressure P _2. Further, while measuring the temperature of the transparent substrate 2,
While maintaining the first temperature T ₁ at the first temperature T ₁ , the first sputtering power W ₁ is applied to the atmosphere in the chamber, an argon plasma is generated and irradiated to the target substrate, and tantalum on the target substrate is sputtered. The reaction between the tantalum atoms or molecules and the reaction gas introduced into the chamber causes the first antireflection film 3a on the transparent substrate 2.
To form

Here, the first pressure P ₁ is 1.5 Pa or less, more preferably 0.1 Pa or less. Second
Is 0.1 Pa to ₂ Pa, preferably 0.1 Pa to 1.0 Pa. Note that the first temperature T
₁ is room temperature (about 20 ° C.) to 500 ° C., more preferably room temperature to 300 ° C., still more preferably room temperature to 500 ° C.
150 ° C. The first sputtering power W ₁ to be introduced during the formation of the first anti-reflection film 3a is, 0.5～20W
/ Cm ² , preferably 1 to 10 W / cm ² . There are no particular restrictions on the spattering speed and time at this time, but the time to obtain the desired film thickness is, for example, 10 seconds to 1 hour, preferably 20 seconds to 30 minutes,
The time is more preferably 30 seconds or more and 20 minutes or less.

The second and third antireflection films 3b and 3c are formed using the same method as the first antireflection film 3a without removing the substrate 2 from the chamber after the formation of the first antireflection film 3a. You.

After the formation of the third antireflection film 3c, the light-shielding film 5 is formed on the third antireflection film 3c without removing the substrate 2 from the chamber. In forming the light-shielding film 5, first, the gas in the chamber is evacuated, and then an argon gas is introduced into the chamber until the pressure is such that plasma can be generated. Next, while maintaining the temperature of the substrate 2 at about room temperature, a sputtering power is applied to the atmosphere in the chamber,
An argon plasma is generated and irradiated to the target substrate, and tantalum on the target substrate is sputtered.
A light-shielding film 5 made of metal tantalum is deposited on the substrate c.

As a method of manufacturing the antireflection films 3a, 3b, 3c and the light shielding film 5, a CVD method or a vapor deposition method may be used.

Next, a positive photoresist is applied to the light shielding film 5.
After applying on the exposed surface of the photoresist, pre-baking, irradiating the photoresist with a pattern having a plurality of openings by light, exposing the photoresist, and then dissolving the photosensitive area of the photoresist using an organic solvent. After development and baking, a photoresist layer having a plurality of openings is formed on the light shielding film 5.

Further, using the photoresist layer having a plurality of openings as a mask, regions of the light-shielding film 5 and the antireflection films 3c, 3b, 3a immediately below the openings are etched by a method such as dry etching. The resist layer is removed from the light-shielding film 5 using an organic solvent to form a black mask BM having a plurality of openings. Note that a CF ₄ gas or the like can be used as a reaction gas used for the dry etching. Further, at the time of manufacturing the present black mask, a waste liquid containing chromium is not generated at the time of etching, so that the handling is easy.

Next, a negative type photoresist that is colored red by containing a red pigment is supplied from a dispenser disposed above the substrate 2 onto the black mask BM, and all of the black mask BM is removed. Fill the opening.

Thereafter, the substrate 2 coated with the red photoresist is pre-baked to form a red photoresist layer having a uniform thickness. Prior to the pre-bake, the substrate 2 was adjusted so that the thickness of the red photoresist layer was uniform.
May be rotated with its thickness direction as a rotation axis.

Next, a red photoresist is applied only to the opening regions adjacent to each other in the row direction and the column direction of the openings arranged in the matrix of the black mask BM in the row direction and the column direction. After exposing the red photoresist layer so as to remain, and removing the red photoresist in the non-photosensitive area using an organic solvent, baking is performed to form a red resin R in a predetermined opening of the black mask BM. .

Further, instead of the red photoresist,
Using a green-colored photoresist and a blue-colored photoresist, a green resin G and a blue resin are formed in predetermined openings of the black mask BM by using the same method as the step of forming the red resin R. Form B. Each of the colored resins R, G, and B is disposed every three in the row direction and the column direction of the opening of the black mask BM, and is arranged so as to be adjacent to the diagonal direction.

Next, an overcoat layer 6 is deposited on the colored resins R, G, and B so that the surface becomes uniform, and a transparent electrode 7 is deposited on the overcoat layer 6, and finally a transparent electrode is deposited. A polarizing plate 8 is attached to the back side of the substrate 2 to complete the color filter 1 shown in FIG.

Next, a liquid crystal display using the color filter 1 will be described.

FIG. 3 is a perspective view showing the liquid crystal display 100. FIG. 4 is a sectional view of the liquid crystal display 100 shown in FIG. The present liquid crystal display 100 includes a color filter 1, a TFT (thin film transistor) substrate 20 attached to the transparent electrode 7 of the color filter 1, and a backlight 26 fixed at a position sandwiching the TFT substrate 20 with the color filter 1. Prepare.

The TFT substrate 20 has an outer frame 21 and an outer frame 2 made of a light-shielding resin surrounding the outer peripheral portion of the surface of the color filter 1.
Liquid crystal layer 2 composed of nematic liquid crystal filled in 1
2. a plurality of pixel electrodes 23 provided for each region corresponding to the black mask BM opening of the liquid crystal layer 22;
Includes a transparent glass substrate 24 formed thereon and a polarizing plate 25 formed on an exposed surface of the transparent glass substrate 24.

The polarizing directions of the polarizing plates or polarizing films 8 and 25 are orthogonal to each other and are made of an organic material such as polyimide. The plurality of pixel electrodes 23 are respectively connected to a plurality of thin film transistors formed on the glass substrate 24 of the TFT substrate 20, and when a specific potential is applied to the specific pixel electrode 23, the specific pixel electrode 23 and the transparent electrode 7, a predetermined voltage is applied to the liquid crystal layer 22, and the orientation of a region corresponding to the specific pixel electrode 23 of the liquid crystal layer 22 changes by an electric field formed according to the voltage.

White light LT emitted from the backlight 26
1 is a polarizing plate or a polarizing film 2
5 and enter the liquid crystal layer 22. The incident polarized light is divided for each pixel electrode 23 and
The polarization direction changes in accordance with the amount of orientation of. The light divided for each pixel electrode 23 is the color resin R of the color filter 1,
G light and B light are respectively incident and transmitted. Since the polarizing plate or the polarizing film 8 is provided on the emission surface side of the color filter 1, the amount of light transmitted through the polarizing plate or the polarizing film 8 changes according to the amount of alignment of the liquid crystal layer 22. Since the amount of orientation of the liquid crystal layer 22 is proportional to the potential applied to the pixel electrode 23, the amount of emitted light LT2 can be controlled by controlling the potential applied to the pixel electrode 23.

As described above, the color filter 1 according to the above-described embodiment includes the black mask BM.
And a transparent substrate 2 on which a black mask BM is formed, and colored resins R, G, and B disposed in a plurality of openings of the black mask BM. In the color filter 1, the black mask BM separates the colored resins R, G, and B arranged in the openings, and thus separates the light transmitted through the colored resins R, G, and B. Since the reflectance of the light irradiated on the black mask BM via the transparent substrate 2 and the wavelength dependence of the reflectance are reduced, the light L transmitted through the colored resins R, G, and B is reduced.
The ratio of the reflected light to T2 can be reduced, and the visibility of the light transmitted through the colored resins R, G, and B can be improved.

The liquid crystal display 100 according to the above-described embodiment has a structure in which the liquid crystal layer 22 is provided by applying a predetermined potential to the color filter 1 and the liquid crystal layer 22 provided at a position facing the color filter 1. A plurality of electrodes 2 provided at positions where the orientation of the liquid crystal layer can be changed for each region facing the plurality of openings of the black mask BM
3 is provided. In the liquid crystal display 100, by applying a predetermined potential to the electrode 23, the alignment can be changed in each region of the liquid crystal layer 22 facing the plurality of openings of the black mask BM. The amount of the input light LT1 is changed to the black mask BM.
Can be controlled for each opening. Black mask BM
Since the colored resins R, G, and B are disposed in the opening of the above, light of a wavelength component corresponding to the colored resins R, G, and B can be emitted for each of the regions. The color filter 1 of the liquid crystal display 100 can improve the visibility of light transmitted through the colored resins R, G, and B, so that a clear image can be displayed on the liquid crystal display 100.

The black mask according to the present invention is not limited to the above-described embodiment, but can be variously modified.

(Second Embodiment) FIG. 5 is a sectional view of a color filter 1 including a black mask BM according to a second embodiment. The black mask BM includes only the first antireflection film 3a and the light shielding film 5. The compositions of the films 3a and 5 are the same as those of the first embodiment, but the thickness of the first antireflection film 3a is 20 to 40n.
m is preferable. The respective films 3a, 5
Can be formed using the same method as the method of forming the films 3a and 5 of the first embodiment.

(Third Embodiment) FIG. 6 is a sectional view of a color filter 1 including a black mask BM according to a third embodiment. The black mask BM includes only the first antireflection film 3a, the second antireflection film 3b, and the light shielding film 5. The compositions of the films 3a, 3b, 5 are the same as those of the first embodiment, however, the thickness of the first and second antireflection films 3a, 3b is preferably 20 to 50 nm. The respective films 3a, 3b, 5
Can be formed using the same method as the method of forming the films 3a, 3b, 5 of the first embodiment.

In the above embodiment, the black mask BM having three or less anti-reflection films and light-shielding films has been described. However, the black mask according to the present invention comprises four or more anti-reflection films and light-shielding films. You may.

[0047]

EXAMPLES The black masks BM according to the first to third embodiments were manufactured, and the reflectance and the wavelength dependence of the reflectance were measured.

Example 1 The black mask BM according to the first embodiment was manufactured by the following method. First, the glass substrate 2 is mounted in a chamber of a sputtering apparatus, and after evacuating the atmosphere in the chamber until the pressure in the chamber becomes 1.0 × 10 ⁻⁴ Pa, a mixed gas of argon gas and oxygen gas is discharged. It was introduced into the chamber until the pressure in the chamber reached 0.4 Pa. The flow rate percentage ratio of the mixed gas supplied to this chamber is Ar: O ₂ = 2: 1.
It is. Further, the sputtering power was set to 2 W / cm ² , and sputtering was performed using metal tantalum as a target to form a 50 nm-thick first antireflection film 3 a containing tantalum oxide on the substrate 2.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, a mixed gas of argon gas, nitrogen gas and oxygen gas was introduced into the chamber until the pressure in the chamber reached 0.4 Pa. The flow rate ratio of the mixed gas supplied to this chamber is Ar: N ₂ : O ₂ = 40: 20: 1. Thereafter, the sputtering power is set to 4 W / cm ² , and sputtering is performed using metal tantalum as a target, and the second antireflection film 3 b having a thickness of 8 nm containing tantalum oxide, tantalum nitride, or tantalum oxynitride is deposited on the first layer. It was formed on the antireflection film 3a.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, a mixed gas of argon gas and oxygen gas was introduced into the chamber until the pressure in the chamber reached 0.4 Pa. The flow rate ratio of the mixed gas supplied to this chamber is A
r: O ₂ = 2: 1. Thereafter, the sputtering power was set to 4 W / cm ² , and sputtering was performed using metal tantalum as a target to form a 30 nm-thick third antireflection film 3c made of tantalum oxide on the second antireflection film 3b.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, argon gas was introduced into the chamber until the pressure in the chamber reached 0.1 Pa. After that, the sputter power is reduced to 5
W / cm ² , sputtering is performed using metal tantalum as a target, and a film thickness of 10
A 0 nm light-shielding film 5 was formed on the third antireflection film 3c.
The temperature of the substrate 2 at the time of forming the films 3a, 3b, 3c, 5 is all room temperature. Thereafter, etching was performed to manufacture the black mask BM according to the first embodiment.

Example 2 A black mask BM according to the second embodiment was manufactured by the following method. First, the glass substrate 2 is mounted in a chamber of a sputtering apparatus, and after the atmosphere in the chamber is evacuated until the pressure in the chamber becomes 1.0 × 10 ⁻⁴ Pa, argon gas, nitrogen gas and oxygen gas are exhausted. The pressure of the mixed gas is set to 0.
It was introduced into the chamber until the pressure reached 4 Pa. The flow rate ratio of the mixed gas supplied to this chamber is Ar: N
₂ : O ₂ = 20: 10: 1. Further, the sputtering power is set to 4 W / cm ² , and sputtering is performed using metal tantalum as a target, and a 26 nm-thick first antireflection film 3 a containing tantalum oxide, tantalum nitride or tantalum oxynitride is formed on the substrate 2. Formed.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, argon gas was introduced into the chamber until the pressure in the chamber reached 0.1 Pa. After that, the sputter power is reduced to 5
W / cm ² , sputtering was performed using metal tantalum as a target, and a film thickness of 12
A 0 nm light-shielding film 5 was formed on the first antireflection film 3a.
The temperature of the substrate 2 at the time of forming the films 3a and 5 is all room temperature. Thereafter, etching was performed to manufacture the black mask BM according to the second embodiment.

Example 3 The black mask BM according to the third embodiment was manufactured by the following method. First, the glass substrate 2 is mounted in a chamber of a sputtering apparatus, and after evacuating the atmosphere in the chamber until the pressure in the chamber becomes 1.0 × 10 ⁻⁴ Pa, a mixed gas of argon gas and oxygen gas is discharged. It was introduced into the chamber until the pressure in the chamber reached 0.4 Pa. The flow rate percentage ratio of the mixed gas supplied to this chamber is Ar: O ₂ = 2: 1.
It is. Further, the sputtering power was set to 2 W / cm ² , and sputtering was performed using metal tantalum as a target to form a first antireflection film 3 a containing tantalum oxide with a thickness of 46 nm on the substrate 2.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, a mixed gas of argon gas and oxygen gas was introduced into the chamber until the pressure in the chamber reached 0.4 Pa. The flow rate ratio of the mixed gas supplied to this chamber is A
r: O ₂ = 2: 1. Thereafter, the sputtering power was set to 4 W / cm ² , sputtering was performed using metal tantalum as a target, and a film thickness 4 containing tantalum oxide was formed.
A second antireflection film 3b of 0 nm was formed on the first antireflection film 3a.

Next, when the pressure in the chamber is 1.0 × 10 ^−4.
After the atmosphere in the chamber was evacuated to Pa, argon gas was introduced into the chamber until the pressure in the chamber reached 0.1 Pa. After that, the sputter power is reduced to 5
W / cm ² , sputtering is performed using metal tantalum as a target, and a film thickness of 10
A 0 nm light-shielding film 5 was formed on the second antireflection film 3b.
The temperature of the substrate 2 when forming the films 3a, 3b, 5 is all room temperature. After that, perform etching,
The black mask BM according to the third embodiment was manufactured.

(Evaluation Method and Results) Examples 1 and 2
The transparent substrate 2 on which the black mask BM according to Example 3 was formed was prepared, incident light was irradiated from the transparent substrate 2 side, and the reflectance of light from the black mask BM was measured.
This reflectivity is measured by the Minolta CM-20 from the glass substrate 2 side.
02 was measured using a spectrophotometer.

FIG. 7 is a graph showing the relationship between the wavelength (nm) of the incident light measured in this way and the reflectance (%). When the black mask BM according to the first embodiment is formed on the transparent substrate 2, the reflectance (E1) is 400 to 400 nm.
It is 5.5% or less over the visible region of 700 nm, and its wavelength dependence is also reduced. Further, when the black mask BM according to the second embodiment is formed on the transparent substrate 2,
Its reflectivity (E2) is 8% or less over the visible range of wavelengths from 500 to 600 nm. Further, when the black mask BM according to the third embodiment is formed on the transparent substrate 2, the reflectance (E3) is 7.5% or less over a visible region of a wavelength of 400 to 700 nm.

The black mask B according to the above-described embodiment is used.
For M, when a black mask pattern is formed by dry etching or the like, a fine and good edge shape can be obtained. Furthermore, after applying a red resist thereon, exposure and development are performed to form a red pixel,
After forming blue and green pixels, and further forming an ITO electrode thereon, forming an alignment film, rubbing, scattering spacers, bonding a counter electrode substrate having a rubbed alignment film on its surface, Liquid crystal display manufactured by performing a series of operations such as injection, sealing, bonding of polarizing film, etc.,
It has low reflection and excellent display performance such as contrast.

[0060]

According to the present invention, there are provided a black mask which is easy to handle at the time of manufacture and whose surface reflectance and the wavelength dependence of the reflectance are reduced, a color filter capable of obtaining a clear image, and a liquid crystal display. It is possible.

[Brief description of the drawings]

FIG. 1 is a perspective view of a color filter.

FIG. 2 is a cross-sectional view of the color filter shown in FIG.

FIG. 3 is a perspective view of a liquid crystal display.

FIG. 4 is a sectional view of the liquid crystal display shown in FIG.

FIG. 5 is a sectional view of a color filter according to another embodiment.

FIG. 6 is a sectional view of a color filter according to another embodiment.

FIG. 7 is a graph showing the relationship between the wavelength (nm) of incident light and the reflectance (%).

[Explanation of symbols]

3a: first antireflection film, 3b: second antireflection film, 3c ...
3rd anti-reflection film, 5 ... light shielding film, BM: black mask,
1: color filter, 100: liquid crystal display.

Claims (6)

[Claims] A first anti-reflection film formed on a transparent substrate and made of a tantalum compound;
And a light shielding film formed on the first anti-reflection film, made of metal tantalum, and shielding visible light. 2. The semiconductor device according to claim 1, further comprising a second antireflection film interposed between the first antireflection film and the light shielding film, the second antireflection film having a composition different from that of the first antireflection film. Item 6. The black mask according to Item 1. 3. The semiconductor device according to claim 1, further comprising a third antireflection film interposed between the second antireflection film and the light shielding film, the third antireflection film having a composition different from that of the first and second antireflection films. The black mask according to claim 2, wherein 4. The tantalum compound includes at least one selected from the group consisting of tantalum oxide, tantalum nitride, tantalum carbide, tantalum oxynitride, tantalum oxycarbide, tantalum oxycarbide, and tantalum oxynitride carbide. The black mask according to any one of claims 1 to 3, wherein: 5. The black mask according to claim 1, the transparent substrate having the black mask formed thereon, and coloring disposed in a plurality of openings of the black mask. And a resin. 6. A first substrate provided with the color filter according to claim 5, a second substrate provided with a plurality of electrodes, sandwiched between the first and second substrates, and applying a predetermined potential to the electrodes. A liquid crystal layer capable of changing the orientation of each of the regions facing the plurality of openings of the black mask.