JP2009282054A - Blanks for black matrix and method for manufacturing the same, substrate with black matrix, color filter substrate and method of manufacturing display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide blanks for a black matrix preferable for a color filter substrate of a thin type display device. <P>SOLUTION: In the blanks for a black matrix, a low reflective film 2 is provided between a glass substrate 1 and a light-shielding film 3, a metal nitride layer containing four components of Ni-Mo-Fe-Ta is provided in the light-shielding film 3, and the metal nitride layer having a Young's modulus 1.6 times or less as large as that of the glass substrate 1 occupies 50% or more in the thickness direction of the light-shielding film 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a black matrix blank used for a flat panel display (FPD), a manufacturing method thereof, a substrate with a black matrix, and a manufacturing method of a display panel.

FPDs such as color liquid crystal display devices (color LCDs) are increasingly used in television broadcast image displays, information display terminals, various monitor displays, and the like.
In these color liquid crystal display devices and the like, a black matrix (hereinafter also referred to as BM) is provided on a color filter substrate used for a color LCD or the like in order to improve display quality such as display contrast of an image. Yes. This BM prevents color mixture of the three primary colors of red, green, and blue adjacent to the color filter (CF), thereby preventing color mixture and preventing color mixture and color display contrast. It is generally used for the purpose of improving the display quality and improving the display quality.
The material of BM is required to satisfy the following requirements, for example, from the viewpoint of withstanding the color LCD manufacturing process.
(1) Easy to manufacture,
(2) A strong film can be formed;
(3) Stable and reliable as a display panel,
(4) A sufficient light shielding characteristic is obtained.
As a material that can meet the above requirements, there is a metal chromium (Cr) film, which is used for a BM of a color liquid crystal display device. However, since Cr has a large environmental load, an alternative metal material for BM has been researched and developed. For example, it has been proposed to use a Ni—Mo—Fe—Ta-based material (see Patent Document 1 and Patent Document 2).
In order to ensure low reflection characteristics, a method of forming a laminated structure by depositing a metal oxide film, a metal oxynitride film, a metal oxycarbide film, or the like between the metal film and the glass substrate is employed. .
Alternatively, a thin glass substrate having a thickness of 0.1 to 0.6 mm is employed from the beginning, and the CF substrate and the TFT array are temporarily used in combination with a relatively thick and physically strong support substrate. A manufacturing method in which a substrate is manufactured, a display panel is assembled, a support substrate is separated from a CF substrate or a TFT array substrate, and a thin glass substrate is used as the substrate of the display panel is also being studied (see Patent Document 3). ).

JP 2002-107537 A International Publication WO2007 / 125875A1 Pamphlet International Publication WO2008 / 007622A1 Pamphlet

In recent years, the thickness of the display panel has been increasingly reduced in the FPD. In particular, there is a great demand for display panels for mobile terminal devices such as mobile phones and PDAs. In portable terminal devices, there is also a demand for lighter devices.
As a method for thinning a display panel, after bonding a CF substrate and a TFT array substrate, the outer surface of the glass substrate is thinned by chemical etching or the like by a chemical method or a physical method.
For example, the standard thickness of FPD plate glass that is generally manufactured is 0.7 mm, or a slightly thin 0.5 to 0.6 mm, in the finished panel state, 0.2 to 0. Etching to reduce the thickness to 3 mm.
However, generally, when the glass substrate becomes thin, it tends to be damaged by applying an external force. A CF substrate in which a CF layer and a transparent conductive film are formed on a glass substrate with BM can be a factor that promotes the tendency of the BM to break. Therefore, as described above, there is a problem that the strength of the finally formed thin glass substrate is lowered.
Conventionally, when the glass substrate has a certain thickness or more, since the strength of the glass substrate itself is originally high, a decrease in strength due to the formation of BM has not been a problem in practice.
However, as a result of the thinning of the display panel in recent years, the display panel as a state incorporated in the final product, the thickness of the glass substrate is further reduced, resulting in insufficient strength of the glass substrate after assembly of the display panel, There is a new problem of breaking the glass substrate.

That is, according to the first aspect of the present invention, a low reflection film is provided between the glass substrate and the light shielding film, the thickness of the glass substrate is 0.6 mm or less, the metal nitride layer is used as the light shielding film, and the metal oxide The layer is used as a low-reflection film, and 0.5 to 3 atomic% of Ta is contained with respect to all metal components of the metal nitride layer. The Young's modulus of the metal nitride layer is the Young's modulus of the glass substrate. Provided is a black matrix blank that is 1.6 times or less and occupies a thickness of 50% or more in the thickness direction of the metal nitride layer.
In this aspect 1, it is preferable that the sum of Ni and Mo is 90 to 99 atomic% with respect to all metal components of the metal nitride layer. Moreover, it is preferable that the sum of Ni and Mo is 90-99 atomic% with respect to all the metal components of the said metal oxide layer.
Aspect 2 provides the black matrix blank according to aspect 1, wherein Ni, Mo, Fe, and Ta are contained so as to satisfy the following conditions with respect to all metal components of the metal nitride layer.
Ni: 75-90 atomic%
Mo: 8-20 atomic%
Fe: 0.5-5 atomic%
Ta: 0.5-3 atomic%
Aspect 3 provides the blank for a black matrix according to Aspect 1 or 2, wherein the metal nitride layer has two or more layers having different compositions, or the composition is changed in the thickness direction. .
Aspect 4 provides the black matrix blanks according to aspects 1, 2, or 3, wherein the glass substrate has a thickness of 0.3 mm or more.
Aspect 5 is a black matrix blank manufacturing method in which a metal oxide layer is formed as a low-reflection film on a glass substrate, and a metal nitride layer is formed as a light-shielding film on the low-reflection film, The thickness of the glass substrate is 0.6 mm or less, and 0.5 to 3 atomic% of Ta is contained with respect to all metal components of the metal nitride layer. The Young's modulus of the metal nitride layer is the Young's modulus of the glass substrate. The metal nitride layer is formed by a sputtering method so that it is 1.6 times or less the rate and occupies a thickness of 50% or more in the thickness direction of the light-shielding film. At that time, the content of nitrogen in the sputtering gas The manufacturing method of the blanks for black matrix which makes 10-30 volume% with respect to the whole sputtering gas is provided.
Aspect 6 provides a substrate with a black matrix formed by patterning the light-shielding film and the low-reflection film of the black matrix blanks according to aspects 1, 2, 3, or 4.
Aspect 7 provides a color filter substrate in which a color filter layer and a transparent conductive film are formed on the black matrix-attached substrate according to aspect 6.
Aspect 8 is a manufacturing method of a display panel formed by combining the color filter substrate according to aspect 7 and a substrate with a TFT array, and the initial thickness of the glass substrate is 0.3 to 0.6 mm, Provided is a method for manufacturing a display panel in which the outer surface of a glass substrate of a color filter substrate is reduced by a chemical method or a physical method, and the thickness of the glass substrate is 0.05 to 0.3 mm.
In this aspect 8, it is preferable that the thickness of the glass substrate on the color filter substrate side after reducing the thickness of the outer surface is 0.05 to 0.2 mm.
In each of the above embodiments, the initial thickness of the glass substrate is preferably within 0.5 mm.
In each of the above aspects, it is preferable that the main metal component of the metal nitride layer constituting the light shielding film and the main metal component of the metal oxide layer constituting the low reflection film are the same. Preferably, it is an alloy containing Ni-Mo.
Furthermore, through the etching process, the thickness of the outer surface of at least one glass substrate is reduced, and the thickness of the glass substrate on one side in the final state assembled as a display panel is 0.05 to 0.3 mm. It is preferable that it is 05-0.2 mm.
Further, a substrate with a black matrix, a color filter substrate, or a display panel can be formed by leaving the original thickness of the glass substrate as it is without performing etching in a subsequent process so as to reduce the thickness of the glass substrate. .
In the above aspect, the light shielding film preferably has an optical value (Optical Density: OD value) of 3.8 or more.
Further, it is preferable that all of the light shielding film in the thickness direction is made of a metal nitride layer containing Ta. Further, the metal nitride layer is preferably a four-component system containing Ni, Mo, Fe, and Ta.

In the present invention, the initial thickness of the glass substrate is 0.6 mm or less, and the strength reduction of the glass substrate in a thin display panel can be prevented. In particular, it is suitable for a color filter substrate or a black matrix substrate for portable terminal devices in which the thickness of at least one of the opposing glass substrates is 0.4 mm or less in the state of the completed display panel.
Furthermore, by using a non-chromium material, specifically, a Ni-Mo alloy-based metal nitride layer as the light-shielding film, a sufficiently strong light-shielding and physically strong BM can be formed. Blanks having excellent optical properties and mechanical properties can be stably produced. In addition, the composition of the light-shielding film and the low reflection film can be easily controlled, and the production management thereof is facilitated. In particular, it is suitable for manufacturing an ultra-thin display panel having a glass substrate thickness of about 0.1 to 0.2 mm.

  The black matrix blanks (hereinafter also referred to as blanks) of the present invention are precursors for producing a substrate with a black matrix (hereinafter also referred to as a substrate with BM). The blank 10 includes a light shielding film 3 and a low reflection film 2 on a glass substrate 1 (see FIG. 1). By patterning the low-reflection film 2 and the light-shielding film 3, the substrate 11 with the BM provided with the opening 4 can be formed (see FIG. 2).

The blank of the present invention uses a metal nitride layer containing 0.5 to 3 atomic percent of Ta as a light-shielding film so as to have a specific Young's modulus, and uses a metal oxide. In combination with the low reflection film, the optical characteristics required for the display panel and the mechanical characteristics required for the thin device are made compatible.
The light-shielding film in the blanks is provided to prevent color loss of each of the three primary colors of red 5R, green 5G, and blue 5B adjacent to the color filter layer (hereinafter also referred to as a CF layer), and further an overcoat layer. 6 and the transparent conductive film 7 are formed (see FIGS. 3 and 4).
3 and 4, a CF layer 5 is provided above the glass substrate 1, the low reflection film 2, and the light shielding film 3. FIG. 5 shows a flowchart of the formation process.

  The light shielding film in the blanks is for obtaining good optical characteristics with respect to the contrast ratio and the like by shielding the periphery of the display portion of each color pixel. In the present invention, a material having a predetermined physical property is selected as a main component of the light shielding film, a single layer or a plurality of layers are formed on a glass substrate, and optical properties and physical properties are adjusted comprehensively and used. is there. The low reflection film is a film formed in order to give excellent low reflectivity to the BM around the color pixel when functioning as a display panel.

  In the present invention, the low reflection film and the light shielding film are laminated in this order on the glass substrate so that the excellent low reflection characteristics in the usage state of the display panel can be satisfied. Another low reflection film may be provided on the light shielding film. Even in the case of a complicated layer structure, layers other than the light shielding film and the low reflection film may be separately provided as long as the original light shielding function can be exhibited.

For measuring the Young's modulus of the metal nitride layer, it is suitable to use a micro surface hardness tester because the thickness of the blank is as thin as 200 nm or less.
Here, the cracking strength of the glass substrate means the resistance to cracking when the periphery of the sample of the glass substrate is fixed and the center of the sample is pushed from the side opposite to the thin film.
As a result of intensive studies, the present inventor has found that the decrease in the cracking strength of the glass substrate is suppressed by setting the Young's modulus of the light-shielding film on the glass substrate to be small. According to the present invention, it has been found that it is possible to meet the thinning of a glass substrate that is widely used in display panels for portable information terminal devices. That is, it was found that even if the substrate was processed thinly, the inherent crack strength of the glass substrate was maintained, and the panel strength in the final product could be sufficiently secured. Of course, the present invention can be applied not only to portable information terminal devices but also to small to medium-sized notebook personal computers.

The operation of the present invention is considered as follows. It is to provide a light-shielding film having a relatively small Young's modulus that is 1.6 times or less of the Young's modulus of the glass substrate. Then, when an external force is applied to the glass substrate of the display panel, the stress on the surface of the light shielding film decreases. Here, the reduction means that the stress is relatively reduced as compared with the case where a light shielding film having a Young's modulus exceeding 1.6 times that of the glass substrate is formed.
As a result, the present invention makes it difficult to cause a glass substrate cracking phenomenon in the display panel, and can be stably put to practical use.

In the present invention, the Ta-containing metal nitride layer constituting the light shielding film may be a substantially uniform single layer or two or more layers (see FIGS. 6 and 7: low reflection films 2a and 2b). 2c), or the composition of the metal nitride layer may be changed in the film thickness direction (see FIG. 8: low reflection film 2X in which the composition is changed). From the viewpoint of manufacturing the light shielding film, it is preferable that the composition of the metal nitride layer gradually changes.
Even when the composition changes in the film thickness direction, the metal nitride layer that is 1.6 times or less the Young's modulus of the glass substrate is provided so as to be 50% or more of the entire light-shielding film in terms of film thickness. Preferably, it is 80% or more, and particularly preferably 100%.

The composition of the metal component of the metal nitride layer constituting the light shielding film is particularly preferably a four-component system of Ni—Mo—Fe—Ta. Furthermore, the composition conditions are preferably Ni: 75 to 90 atomic%, Mo: 8 to 20 atomic%, Fe: 0.5 to 5 atomic%, and Ta: 0.5 to 3 atomic%. By adjusting the composition conditions and the amount of nitrogen in the sputtering gas, which will be described later, it is possible to further suppress the decrease in the cracking strength of the glass substrate.
First, the Ni content of the metal nitride layer in the light shielding film is preferably set to the above composition from the viewpoints of durability and workability. When the Ni content is less than 75 atomic%, the durability deteriorates. On the other hand, if it exceeds 90 atomic%, the etching rate becomes slow, and it becomes difficult to form a BM by patterning.

Next, the Mo content is preferably the above composition from the viewpoint of durability and workability. If the Mo content is less than 8 atomic%, the etching rate becomes slow, and it becomes difficult to form a BM by patterning. On the other hand, if it exceeds 20 atomic%, durability (particularly water resistance) deteriorates.
In the present invention, the composition of the metal nitride layer constituting the light-shielding film preferably contains 90 to 99 atomic percent of Ni—Mo with respect to all metal components.

  Next, Fe in the light-shielding film has an effect of improving water resistance, and preferably contains 0.5 atomic% or more of Fe. When the light-shielding film does not contain Fe, the electronic device can be manufactured while maintaining the optical characteristics of the CF layer satisfactorily by sufficiently managing the moisture in the subsequent process of processing the blanks. On the other hand, if Fe exceeds 5 atomic%, the water resistance deteriorates, which is not preferable.

Finally, the content of Ta is set to the above composition from the viewpoint of the cracking strength, Young's modulus, and workability of the glass substrate. By adding at least 0.5 atomic% of Ta, the Young's modulus can be reduced due to a synergistic effect with the amount of nitrogen in the sputtering gas, and thus a decrease in crack strength can be suppressed.
If Ta is less than 0.5 atomic%, the effect is difficult to obtain, and if it exceeds 3 atomic%, the etching rate becomes slow and it becomes difficult to form a BM by patterning.
When Ta is included in the light-shielding film, the patterning property is lowered. However, by optimizing the manufacturing apparatus and manufacturing process in the patterning process, a pattern equivalent to the blank made of the light-shielding film without adding Ta is formed. Is possible. Specifically, the patterning property of the light-shielding film using the metal nitride layer containing Ta can be improved by optimizing the cleaning conditions and the baking conditions of the photoresist.

Furthermore, in the present invention, as the material of the metal nitride layer constituting the light shielding film, one or more metals such as Al, Ti, Zr, V, W, Co, and Nb are used, and the effects of the present invention are not impaired. It can be contained in a range. For example, you may contain so that it may become 15 atomic% or less with respect to all the metal components.
Furthermore, from the viewpoint of waste liquid treatment and waste liquid management, it is preferable that the low reflection film and / or the light shielding film do not contain metallic chromium. Further, it is preferable that the blank is substantially free of metallic chromium. The fact that metal chromium is substantially not included means that the content of metal chromium is 0.1 atomic% or less with respect to all the metal components of the light shielding film.

The light shielding film of the present invention includes a metal nitride layer containing Ta as a constituent material. Due to the synergistic effect with the above composition conditions, it is possible to suppress a decrease in crack strength. Further, since the etching rate can be increased, it is effective for controlling the etching rate.
Furthermore, the patterning property can be improved in accordance with the improvement of the etching rate. The nitrogen content is preferably 2 to 10 atomic% with respect to all elements of the metal nitride layer. In particular, it is preferably 3 to 6 atomic%. If the nitrogen content is less than 2 atomic%, the effect of suppressing the cracking strength of the glass substrate is difficult to obtain, and if it exceeds 10 atomic%, the etching rate of the light-shielding film becomes too fast, which is not preferable.
In the present invention, when the light shielding film layer is formed by a sputtering method, the above-mentioned metal nitride layer containing Ta can be formed by adding nitrogen gas to the sputtering gas. The nitrogen gas content in the sputtering gas is preferably 10 to 30% by volume, more preferably 15 to 30% by volume. In addition, oxygen and carbon may be contained in the light shielding film as long as the effect of the present invention is not impaired. However, in terms of light shielding properties, the total content of oxygen and carbon is based on the total elements of the light shielding film. It is preferably 4 atomic% or less.

  Examples of the glass substrate used in the present invention include a colorless and transparent soda lime glass substrate, a quartz glass substrate, a borosilicate glass substrate, and an alkali-free glass substrate. As for the thickness of the glass substrate, it is preferable that the thickness of the glass substrate on at least one side is 0.3 mm or less in the state after the display panel is assembled from the viewpoint of weight reduction and thickness reduction in mobile use.

The low reflection film used in the blank of the present invention is not particularly limited, but it is preferable that a Ni—Mo alloy is a main component from the viewpoint of workability and durability.
The Ni content of the low reflection film is 75 to 90 atomic% with respect to all metal components from the viewpoint of durability and workability. When the Ni content is less than 75 atomic%, the durability deteriorates. On the other hand, if it exceeds 90 atomic%, the etching rate becomes slow, and it becomes difficult to form a BM by patterning.
The Mo content of the low reflection film is 8 to 20 atomic% with respect to all metal components from the viewpoint of durability and workability. If the Mo content is less than 8 atomic%, the etching rate becomes slow, and it becomes difficult to form a BM by patterning at a normally required production rate.
Moreover, when it exceeds 20 atomic%, durability (especially water resistance) will deteriorate. Furthermore, if it exceeds 15 atomic%, the etching rate becomes too fast, and it becomes difficult to stably produce when patterning to form a BM.

The low reflection film may contain other metals in addition to Ni and Mo. The other metal is preferably Fe, and the Fe content is preferably 0.5 to 5 atomic% with respect to the total metal components. By containing Fe in the above range, water resistance can be improved. If it is less than 0.5 atomic%, it is difficult to obtain the effect, and if it exceeds 5 atomic%, the water resistance deteriorates.
Further, the low reflection film can contain one or more metals such as Ta, Al, Ti, Zr, V, W, and Co in a range not impairing the effects of the present invention. For example, it is preferable to contain on the conditions of 15 atomic% or less with respect to all the metal components.

It is preferable that the oxygen content rate of the metal oxide layer which comprises a low reflection film is 5-65 atomic% with respect to all the elements of a low reflection film. In that case, it is preferable that the content rate of the metal component of Ni or Mo is 30 to 80 atomic% with respect to the elements of the entire low reflection film.
The low reflection film may further contain nitrogen or carbon. The etching rate can be controlled by including nitrogen or carbon. The nitrogen content is preferably 0.1 to 50 atomic% with respect to all elements of the low reflection film. Moreover, it is preferable that the total content rate of oxygen and nitrogen is 20-70 atomic% with respect to all the elements of a low reflection film. The carbon content is preferably 0.1 to 15 atomic% with respect to all elements of the low reflection film.
In the case of forming the low reflection film by a sputtering method, oxygen can be contained by adding O ₂ to the sputtering gas. Similarly, if N ₂ is added to the sputtering gas, nitrogen is added to the low reflection film, and if CO ₂ or CO is added to the sputtering gas, carbon and oxygen are added to the low reflection film.

The low reflection film may be not only one layer but also two or more layers. Even if the low reflection film has two or more layers, each layer preferably has the above-described configuration.
The thickness of the light shielding film is preferably 90 to 130 nm from the viewpoint of setting the OD value in the visible region to about 4.0. The thickness of the low reflection film is 40 to 70 nm (when the low reflection film is a single layer) or 5 to 70 nm (low) from the viewpoint of setting the reflectance over the visible region to 3% or less (excluding the reflectance of glass). The thickness of one layer in the case of two or more reflective films is preferred.

The light-shielding film and the low-reflection film constituting the blank of the present invention are preferably formed by a sputtering method from the viewpoint of film durability and film thickness uniformity. For example, the low reflection film can be formed by sputtering in an oxidizing gas atmosphere using a Ni—Mo—Fe alloy target.
The light shielding film can be formed by sputtering in a mixed gas atmosphere of an inert gas and a nitrogen gas using a Ni—Mo—Fe—Ta alloy target. Therefore, in order to form the low reflection film and the light shielding film on the glass substrate, it can be achieved by continuously performing the above manufacturing method.
Here, the oxidizing gas atmosphere means an atmosphere containing at least one of O _{2 and} CO ₂ and further mixed with a gas such as Ar or N ₂ . As the inert gas, one or more selected from the group consisting of He, Ne, Ar, and Kr gas can be used as the sputtering gas. In particular, Ar gas is preferably used from the viewpoint of stabilizing discharge during sputtering and suppressing production cost.
The sputtering pressure is suitably 0.1 to 2 Pa. The back pressure is preferably 1 × 10 ⁻⁶ to 1 × 10 ⁻² Pa. The substrate temperature is preferably room temperature to 300 ° C., and particularly preferably room temperature to 200 ° C. from the viewpoint of durability and productivity.

Furthermore, the present invention provides a BM formed by patterning the blank. The composition and configuration of the blank film as described above can be applied as they are to the composition and configuration of the film (light shielding film / low reflection film) in the BM.
The substrate with BM of the present invention applies a photoresist to the above blanks, forms a matrix pattern, and removes unnecessary portions of the blanks such as a light shielding film and a low reflection film with an etching solution according to the pattern of the photoresist. (See FIG. 4).
Examples of the etching solution include cerium ammonium nitrate, a mixture of perchloric acid and water, cerium ammonium nitrate, a mixture of nitric acid and water, a mixture of phosphoric acid, nitric acid, acetic acid and water, and the like.

  In addition, the present invention provides a CF substrate using the above substrate with BM (see FIG. 3). As the CF layer, each of the red 5R, green 5G, and blue 5B CF layers is formed on a glass substrate with a BM on which the BM is formed by photolithography, and a planarizing film 6 and a transparent conductive film 7 are sequentially formed. It is manufactured by.

  Furthermore, the present invention provides a display panel using the above CF substrate. For the display panel, a CF substrate and a TFT array substrate are attached, and if necessary, the outer surface side of the glass substrate is shaved by a chemical or physical method to reduce the thickness of the outer surface of at least one of the glass substrates. It can be manufactured by thinning. FIG. 5 shows a flowchart of the manufacturing process up to the formation of the display panel. Examples 1-17 are shown below and this invention is demonstrated. Examples 3, 5, and 6 are examples, and other examples are comparative examples.

(Examples 1-15)
A 0.6 mm-thick alkali-free glass substrate (Asahi Glass Co., Ltd .: AN100, Young's modulus 77 GPa) was washed, and then set as a substrate in a sputtering apparatus. A low reflection film having a thickness of 50 nm was formed on the substrate by a direct current magnetron sputtering method using a Ni—Mo—Fe alloy target having an atomic percentage (%) of 79: 17: 4.
The sputtering gas was an Ar gas containing 50% by volume of CO ₂ gas, the back pressure was 1.3 × 10 ⁻³ Pa, the sputtering gas pressure was 0.3 Pa, and the input power density was 2.2 W / cm ² . Moreover, the glass substrate was not heated. As a result, the composition of the formed metal oxide layer as the low reflection film was the same as that of the alloy target used.
After exhausting the residual gas, a thickness of the Ni-Mo-Fe-Ta alloy target or Ni-Mo-Fe alloy target having the composition shown in Table 1 is formed on the low reflection film by a direct current magnetron sputtering method. Blanks were manufactured by forming a light-shielding film having a thickness of 110 nm.
As the sputtering gas, a mixed gas of Ar and nitrogen mixed at a ratio shown in Table 1 was used. The back pressure was 1.3 × 10 ⁻³ Pa, the sputtering gas pressure was 0.3 Pa, and the input power density was 2.1 W / cm ² . Moreover, the glass substrate was not heated.
When the composition of the metal component of the light shielding film was measured by ICP emission analysis, it was equal to the composition of the target.

The crack strength of the blanks of this example and the Young's modulus of the light shielding film were evaluated by the following methods. The results are shown in Table 1.
(1) Cracking strength Blanks were cut into a 40 × 40 mm sample and placed on a 30 mm-diameter ring with the film surface facing downward. Next, a spherical object having a diameter of 10 mm was pushed into the center of the sample from the opposite side of the film surface, and the load when the sample was cracked was measured. The same evaluation was performed on 10 to 20 samples, and a load having a fracture probability of 50% was statistically obtained from a Weibull plot of the load and the fracture probability.
A load with a 50% fracture probability of a 0.6 mm-thick non-alkali glass substrate in which no film was formed on the glass substrate was set as a reference value. Next, the ratio of the blanks load to this reference value was determined. In the evaluation, the case of 0.8 times or more was given as ◯, and the case of less than 0.8 times was given as x.
(2) Young's modulus of light shielding film Blanks were cut into a sample having a size of 10 × 10 mm, and Young's modulus was measured using a nano indenter (Nano Indenter SA2: manufactured by MTS Systems). Measurement was continuously performed from the film surface to a depth of 500 nm, and a Young's modulus at a depth of about 10 nm was obtained. The same measurement was performed 10 times, and the average value excluding the abnormal value was evaluated as the Young's modulus of the light shielding film. The Poisson's ratio necessary for deriving the Young's modulus was 0.25.
Further, before and after the Young's modulus measurement of the light shielding film, the measurement was performed using the quartz substrate as a standard sample, and it was confirmed that the measurement accuracy was ensured. The ratio of Young's modulus of the light-shielding film of each example to the Young's modulus of the alkali-free glass substrate on which no film is formed is obtained. When satisfying the condition of 1.6 times or less, ○, when exceeding 1.6 times X was evaluated.

(Examples 16 and 17)
A low reflective film was formed by sputtering in the same manner as in Example 1 except that a Cr metal target was used and the sputtering gas was N ₂ gas containing 20% by volume of CO ₂ gas. Then, a substrate with a low reflection film having a thickness of 50 nm was formed. Subsequently, a blank was obtained by forming a light-shielding film having a thickness of 110 nm on the low-reflection film by the same method except that a Cr metal target was used.
By the same method as in Example 1, the crack strength and the Young's modulus of the light shielding film were evaluated. The results are shown in Table 1.

From Table 1, it can be seen that when the Young's modulus of the metal nitride layer constituting the light shielding film is more than 1.6 times the Young's modulus of the glass substrate, the crack strength of the blanks is weak. On the other hand, when the Young's modulus of the light shielding film is 1.6 times or less of the Young's modulus of the glass substrate, it can be seen that the cracking strength is strong.
In particular, the Ni-Mo-Fe-Ta alloy quaternary metal nitride layer is used as the main constituent film of the light-shielding film, and a large amount of nitrogen is introduced during the formation of the light-shielding film, thereby reducing the Young's modulus of the light-shielding film As a result, it was found that a decrease in crack strength was suppressed.
On the other hand, when Ni—Mo—Fe—alloy or Cr is used as the light shielding film, the Young's modulus of the light shielding film is high regardless of the amount of nitrogen, and as a result, the crack strength tends to decrease.

(Creation of CF substrate and display panel)
A CF substrate is produced using the blanks of Examples 3, 5 and 6 above. Further, this CF substrate and a separately prepared substrate with a TFT array are bonded together. Next, a thin display panel can be obtained by thinning the glass substrate on the outer surface side of the CF substrate to 0.2 mm by a chemical method or a physical method.
It is confirmed that the display panel formed in this way has a higher cracking strength than the case of using the blanks of the comparative example.

  The blank in the present invention is suitable for a color filter substrate because the Young's modulus of the light shielding film is small and the crack strength is not lowered. In particular, it is useful for a display panel for mobile use, which is becoming thinner and lighter.

FIG. 1 is a schematic cross-sectional view of an example of a blank according to the present invention. FIG. 2 is a schematic cross-sectional view of an example of a substrate with a BM according to the present invention. FIG. 3 is a schematic cross-sectional view of an example of a color filter substrate according to the present invention. FIG. 4 is a schematic cross-sectional view showing the layer formation process in the manufacturing process of the present invention. FIG. 5 is a flowchart of the manufacturing method according to the present invention. FIG. 6 is a schematic cross-sectional view when the low reflection film has a two-layer structure. FIG. 7 is a schematic cross-sectional view when the low reflection film has a three-layer structure. FIG. 8 is a schematic cross-sectional view when the composition of the low reflection film is configured to change continuously.

Explanation of symbols

1: Glass substrate 2: Low reflection film 3: Light-shielding film 4: Opening part 5: Color filter layer 6: Overcoat layer (OC layer)
7: Transparent conductive film

Claims (8)

A low reflection film is provided between the glass substrate and the light shielding film, the thickness of the glass substrate is 0.6 mm or less, the metal nitride layer is used as the light shielding film, the metal oxide layer is used as the low reflection film,
0.5 to 3 atomic% of Ta is contained with respect to the total metal components of the metal nitride layer,
The black matrix blanks wherein the Young's modulus of the metal nitride layer is 1.6 times or less of the Young's modulus of the glass substrate, and the metal nitride layer occupies a thickness of 50% or more in the thickness direction of the light shielding film. The black matrix blank according to claim 1, wherein Ni, Mo, Fe, and Ta are contained so as to satisfy the following conditions with respect to all metal components of the metal nitride layer.
Ni: 75-90 atomic%
Mo: 8-20 atomic%
Fe: 0.5-5 atomic%
Ta: 0.5-3 atomic%   3. The black matrix blank according to claim 1, wherein the metal nitride layer is composed of two or more layers having different compositions, or the composition is changed in the thickness direction. 4.   The black matrix blanks according to any one of claims 1 to 3, wherein the glass substrate has a thickness of 0.3 mm or more.   A method of manufacturing a blank for a black matrix, comprising forming a metal oxide layer as a low-reflection film on a glass substrate, and forming a metal nitride layer as a light-shielding film on the low-reflection film, the thickness of the glass substrate Is 0.6 mm or less, and 0.5 to 3 atomic% of Ta is contained with respect to all metal components of the metal nitride layer. The Young's modulus of the metal nitride layer is 1. The metal nitride layer is formed by a sputtering method so as to be 6 times or less and occupy a thickness of 50% or more in the thickness direction of the light-shielding film. The manufacturing method of the blanks for black matrices made into 10-30 volume% with respect to the whole.   The board | substrate with a black matrix formed by patterning the light shielding film and low reflection film of the blank for black matrices of any one of Claims 1-4.   A color filter substrate comprising a color filter layer and a transparent conductive film formed on the black matrix-attached substrate according to claim 6. A manufacturing method of a display panel, which is formed by combining the color filter substrate according to claim 7 and a substrate with a TFT array,
The initial thickness of the glass substrate is 0.3 to 0.6 mm,
A method for manufacturing a display panel, wherein the outer surface of a glass substrate of a color filter substrate is reduced by a chemical method or a physical method, and the thickness of the glass substrate is 0.05 to 0.3 mm.

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