TW201942664A - Phase shift mask blanks, manufacturing method of phase-shift mask blanks, and manufacturing method of display device for patterning a phase shift film into a cross-sectional shape with a high transmittance to sufficiently exhibit a phase shift effect - Google Patents

Abstract

The present invention provides a phase shift mask blank which can pattern a phase shift film into a cross-sectional shape with a high transmittance to sufficiently exhibit a phase shift effect. The phase shift mask blank of the present invention has a phase shift film provided on a transparent substrate, and an etched mask film on the phase shift film, a specific pattern formed on the etched mask film is preferably used as a mask. The phase shift mask blanks having phase shift patterns are formed by wet etching process on the transparent substrate, wherein the phase shift film contains a transition metal, silicon, oxygen, and nitrogen, The content of oxygen contained in the phase shift film is 5 atom% or more and 70 atom% or less, and the ratio of the transition metal to silicon contained in the phase shift film is 1:1.5 or more and 1:6 or less, and the film stress of the phase shift film is 0.35 GPa or less.

Description

Phase shift mask base, method for manufacturing phase shift mask, and method for manufacturing display device

The present invention relates to a method for manufacturing a phase shift mask substrate, a phase shift mask using the same, and a method for manufacturing a display device.

In recent years, display devices such as FPD (Flat Panel Display) represented by LCD (Liquid Crystal Display) are rapidly advancing the large screen, wide viewing angle, high definition, and high speed display. One of the elements required to achieve this high-definition and high-speed display is the production of electronic circuit patterns such as fine elements and wiring with high dimensional accuracy. In the patterning of electronic circuits for display devices, a photolithography method is often used. Therefore, a phase shift mask for manufacturing a display device having a fine and highly accurate pattern is required.

For example, Patent Document 1 discloses a method of diluting phosphoric acid, hydrogen peroxide, and ammonium fluoride in water while minimizing damage to a transparent substrate when wet-etching a thin film containing molybdenum silicide. A base mask for a flat panel display which wet-etches a thin film containing molybdenum silicide and a mask using the same.
Further, in Patent Document 2, for the purpose of improving the precision of a pattern, it is disclosed that a phase reversal film 104 includes films having mutually different compositions that can be etched using the same etching solution, and each film having a different composition is laminated 1 Phase reversal base mask and photomask formed in the form of a multilayer film or continuous film of at least 2 layers or more.
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Korean Patent Application Publication No. 10-2016-0024204
[Patent Document 2] Japanese Patent Laid-Open No. 2017-167512

[Problems to be solved by the invention]

In recent years, as a phase-shifting mask substrate for the manufacture of such display devices, in order to reliably transfer a fine pattern of less than 2.0 μm, research is being conducted at a certain ratio (5 atomic% or more, and further 10 atomic%). The phase shift film containing oxygen is used as a phase shift film having optical characteristics in which the transmittance of the phase shift film to the exposed light is 10% or more, and furthermore, 20% or more. However, it is known that in such a case where a phase shift film having an oxygen content of 5 atomic% or more and further 10 atomic% or more is patterned by wet etching, a wet etching solution is immersed in the phase shift. At the interface between the film and the etching mask film formed thereon, the etching of the interface portion will be performed earlier. As a result, the etching mask film pattern is used as a mask to form a phase shift film pattern, and the etching mask film pattern is peeled from the phase shift film and the phase shift film pattern cannot be formed. In this case, the cross-sectional shape of the edge portion of the formed phase-shifting film pattern is also inclined, and becomes a tapered shape in which the foot portion is stretched.

In the case where the cross-sectional shape of the edge portion of the phase shift film pattern is a cone shape, as the film thickness of the edge portion of the phase shift film pattern decreases, the phase shift effect decreases. Therefore, the phase shift effect cannot be fully exerted, and a fine pattern less than 2.0 μm cannot be stably transferred. If the content of oxygen in the phase shift film is set to 5 atomic% or more and further 10 atomic% or more, it is difficult to strictly control the cross-sectional shape of the edge portion of the phase shift film pattern, and it is very difficult to control the line width (CD, Critical Dimension ).

Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a phase shift mask having a high transmittance capable of patterning a phase shift film into a cross-sectional shape that can fully exert a phase shift effect by wet etching. A method for manufacturing a substrate, a phase shift mask having a phase shift film pattern capable of fully exerting a phase shift effect, and a method for manufacturing a display device using the phase shift mask.
[Technical means to solve the problem]

In order to solve these problems, the present inventors have intensively studied a method of verticalizing a cross-sectional shape of an edge portion of a phase shift film pattern. Previously, it has been considered to determine the wet etching rate or patterning characteristics in a composition ratio. However, through experiments and investigations on phase shift films and etch mask films containing transition metals, silicon, oxygen, and nitrogen, it was found that the oxidation of transition metals existing at the interface between the phase shift film and the etch mask film The main reason for the immersion of materials. In addition, the inventors have conducted further research and found that even if the composition of the phase shift film is not significantly different, by setting the film stress of the phase shift film to 0.35 GPa or less, it is possible to set the etching rate before being affected by the interface immersion. In order to finish the patterning of the phase shift film by wet etching at a faster etching rate, it is not necessary to use the etching mask film pattern as a mask to form the phase shift film pattern by wet etching. The etching mask film pattern is peeled off in the middle to form a phase shift film pattern reliably, and further, the phase shift film pattern can be formed into a cross-sectional shape that can fully exhibit the phase shift effect. In particular, it has been found that the wet etching solution is particularly prone to be immersed in the case where the etching mask film has a columnar structure from the interface between the phase shift film and the etching mask film. The columnar structure described herein refers to a state where particles of the material constituting the etching mask film have a columnar particle structure extending toward the film thickness direction of the etching mask film (the direction in which the particles are stacked). The present invention has been completed from the result of earnest research as described above, and has the following constitution.

(Composition 1) A phase-shifting mask substrate, characterized in that: it is provided with a phase-shifting film on a transparent substrate and an etching mask film on the phase-shifting film; and the phase-shifting mask substrate is used for Using the above-mentioned etching mask film with an etching mask film pattern having a specific pattern as a mask, and wet-etching the phase shift film on the transparent substrate to form an original version of the phase shift mask with a phase shift film pattern;
The phase shift film contains transition metals, silicon, oxygen, and nitrogen;
The content of oxygen contained in the phase shift film is 5 atomic% or more and 70 atomic% or less;
The ratio of transition metal to silicon contained in the phase shift film is 1: 1.5 or more and 1: 6 or less;
The film stress of the phase shift film is 0.35 GPa or less.

(Structure 2) The phase-shifting mask substrate according to Structure 1, wherein the nitrogen content in the phase-shifting film is 2 atomic% or more and 60 atomic% or less.
(Composition 3) The phase shift mask substrate according to constitution 1 or 2, wherein the content rate of oxygen contained in the phase shift film is greater than the content rate of nitrogen.
(Composition 4) The phase shift mask substrate according to any one of constitutions 1 to 3, wherein the phase shift film is composed of a plurality of layers or a single layer.

(Composition 5) The phase shift mask substrate according to any one of constitutions 1 to 4, wherein the etching mask film includes a chromium-based material.
(Structure 6) The phase-shift mask substrate according to any one of Structures 1 to 5, wherein the etching mask film has a columnar structure.

(Composition 7) The phase shift mask substrate according to any one of the constitutions 1 to 6, wherein the etching mask film contains at least any one of nitrogen, oxygen, and carbon.

(Composition 8) The phase-shifting mask base according to any one of constitutions 1 to 7, wherein the transparent substrate is a rectangular substrate, and the length of the short side of the transparent substrate is 300 mm or more.

(Composition 9) A method for manufacturing a phase shift mask, which is characterized by including the following steps:
Prepare the phase shift mask substrate as described in any one of 1 to 8;
Forming a resist film on the phase shift mask substrate;
Drawing and developing a desired pattern on the above-mentioned resist film, thereby forming a resist film pattern, using the resist film pattern as a mask, and patterning the etching mask film by wet etching The etching mask film pattern; and using the etching mask film pattern as a mask, the phase shift film is wet-etched on the transparent substrate to form a phase shift film pattern.

(Composition 10) A method for manufacturing a display device, which comprises the steps of using a phase shift mask manufactured by constituting the phase shift mask base described in any one of 1 to 8 or using a phase shift mask The phase shift mask manufactured by the described method of manufacturing a phase shift mask is a step of exposing a transfer pattern to a resist film on a display device.
[Effect of the invention]

According to the phase shift mask substrate of the present invention, even when the phase shift film contains transition metals, silicon, oxygen, and nitrogen, and the content rate of oxygen is a certain value or more, the pattern of the etched mask film can be used as When the mask forms a phase shift film pattern by wet etching, the phase shift film pattern is reliably formed without removing the etching mask film pattern in the middle, and further, the phase shift film can be patterned into A phase shift mask substrate with a high transmittance in a cross-sectional shape that can fully utilize the phase shift effect. In addition, a phase shift mask substrate capable of patterning a phase shift film into a cross-sectional shape with a small CD deviation can be obtained by wet etching.

In addition, according to the method for manufacturing a phase shift mask of the present invention, the phase shift mask is manufactured using the phase shift mask substrate described above. Therefore, it is possible to manufacture a phase-shifting mask having a phase-shifting film pattern which can fully exert a phase-shifting effect. In addition, a phase shift mask having a phase shift film pattern with a small CD deviation can be manufactured. This phase shift mask can cope with the miniaturization of line and gap patterns or contact holes.

In addition, according to the manufacturing method of the display device of the present invention, a display device is manufactured using a phase shift mask manufactured using the above-mentioned phase shift mask substrate or a phase shift mask obtained by the above-described phase shift mask manufacturing method. Therefore, a display device having a fine line and gap pattern or a contact hole can be manufactured.

Embodiment 1.
In the first embodiment, a phase shift mask base will be described. The phase shift mask substrate is used to form an etching mask film pattern with a desired pattern formed on the etching mask film as a mask, and the phase shift film is formed on the transparent substrate by wet etching to form a phase shift film pattern. The original version of the phase shift mask.

FIG. 1 is a schematic view showing a film configuration of a phase shift mask substrate 10.
The phase shift mask substrate 10 shown in FIG. 1 includes a transparent substrate 20, a phase shift film 30 formed on the transparent substrate 20, and an etch mask film 40 formed on the phase shift film 30.

The transparent substrate 20 is transparent to light exposed. When the transparent substrate 20 has no surface reflection loss, it has a transmittance of 85% or more with respect to the exposed light, and preferably a transmittance of 90% or more. The transparent substrate 20 includes a material containing silicon and oxygen, and may be composed of glass materials such as synthetic quartz glass, quartz glass, aluminosilicate glass, soda lime glass, and low thermal expansion glass (SiO ₂ -TiO ₂ glass, etc.). When the transparent substrate 20 is made of low thermal expansion glass, the position change of the phase shift film pattern caused by the thermal deformation of the transparent substrate 20 can be suppressed. The transparent substrate 20 for a phase-shifting mask base used in display device applications is generally a rectangular substrate, and the length of the short side of the transparent substrate used is 300 mm or more. The invention can provide a phase shift mask capable of stably transferring a fine phase shift film pattern formed on the transparent substrate, for example, up to 2.0 μm, even if the length of the short side of the transparent substrate is larger than 300 mm. Phase shift mask substrate.

The phase shift film 30 includes a transition metal silicide-based material containing a transition metal, silicon, oxygen, and nitrogen. The transition metal is preferably molybdenum (Mo), tantalum (Ta), tungsten (W), titanium (Ti), zirconium (Zr), or the like. Content rate of oxygen contained in phase shift film 30 From the viewpoint of light transmittance and etching rate with respect to exposed light, the content rate of oxygen contained in phase shift film 30 is 5 atomic% or more and 70 atomic%. the following. Preferably, the content of oxygen contained in the phase shift film 30 is preferably 10 atomic% or more and 70 atomic% or less, more preferably 20 atomic% or more and 60 atomic% or less, and further preferably It is 25 atomic% or more and 50 atomic% or less.
In addition, by making the content rate of oxygen contained in the phase shift film 30 greater than the content rate of nitrogen, the transmittance of the phase shift film to the exposed light can be effectively increased. In addition, since the wet etching speed when patterning is performed by wet etching can be accelerated, when the etching mask film pattern is used as a mask to form a phase shift film pattern by wet etching, it is not in the middle of wet etching. The etching mask film pattern is peeled off to form a phase shift film pattern reliably. Furthermore, the phase shift film pattern can be formed into a favorable cross-sectional shape which can fully exhibit a phase shift effect.
From the viewpoint of the wet etching rate and chemical resistance of the phase shift film 30, the ratio of the transition metal to silicon contained in the phase shift film 30 is set to 1: 1.5 or more and 1: 6 or less. When the ratio of the transition metal to silicon contained in the phase shift film 30 is less than 1: 1.5, the cleaning solution (sulfuric acid used in the cleaning process of the phase shift mask substrate or the phase shift mask) Hydrogen oxide mixtures, ammonia water hydrogen peroxide mixtures, ozone water, etc.) are not good because they deteriorate. In addition, when the ratio of the transition metal to silicon contained in the phase shift film 30 exceeds 1: 6, the wet etching rate during patterning by wet etching becomes slow, which is not preferable. The ratio of the transition metal to silicon contained in the phase shift film 30 is preferably 1: 1.5 or more and 1: 4 or less, more preferably 1: 1.6 or more and 1: 3.8 or less, and further preferably 1: 1.7 or more and 3.6. the following.
When nitrogen is contained in the phase shift film 30, the refractive index can be increased, and therefore the film thickness for obtaining a retardation can be reduced, which is preferable in this respect. However, if nitrogen is contained in the phase shift film 30 in a large amount, the wet etching rate becomes slower. The phase shift film 30 has a desired optical characteristic (transmittance, phase difference). From the viewpoint of a wet etching rate, the content rate of nitrogen contained in the phase shift film 30 is preferably 2 atomic% or more and 60 atomic% or less, more preferably 2 atomic% or more and 50 atomic% or less, still more preferably 3 atomic% or more and 30 atomic% or less, still more preferably 5 atomic% or more and 25 atomic% or less.
Examples of the transition metal silicide-based material include oxynitride of a transition metal silicide and oxynitride carbide of a transition metal silicide. If the transition metal silicide-based material is a molybdenum silicide-based material (MoSi-based material), zirconium silicide-based material (ZrSi-based material), and molybdenum-zirconium silicide-based material (MoZrSi-based material), it is easy to obtain The excellent pattern cross-sectional shape formed is preferable in this respect.
The phase shift film 30 has a function of adjusting the reflectance of light incident from the transparent substrate 20 side (hereinafter referred to as the case of the back reflectance) and a function of adjusting the transmittance and phase difference of the exposed light.
The phase shift film 30 can be formed by a sputtering method.

The transmittance of the phase shift film 30 to the exposed light satisfies a value required as the phase shift film 30. The transmittance of the phase shift film 30 is preferably 10% to 70%, more preferably 15% to 65%, and more preferably light of a specific wavelength (hereinafter referred to as a representative wavelength) contained in the exposed light. It is 20% ~ 60%. That is, in the case where the exposed light is a composite light containing light in a wavelength range of 313 nm to 436 nm, the phase shift film 30 has the above-mentioned transmittance for light of a representative wavelength contained in the wavelength range. For example, when the exposed light is a combination of i-rays, h-rays, and g-rays, the phase shift film 30 has the above-mentioned transmittance to any of i-rays, h-rays, and g-rays.
The transmittance can be measured using a phase shift amount measuring device or the like.

The phase difference of the phase shift film 30 with respect to the exposed light satisfies a value required as the phase shift film 30. The phase difference of the phase shift film 30 is preferably 160 ° to 200 °, and more preferably 170 ° to 190 ° for light having a representative wavelength contained in the exposed light. With this property, the phase of light of a representative wavelength contained in the exposed light can be changed from 160 ° to 200 °. Therefore, a phase difference of 160 ° to 200 ° occurs between light having a representative wavelength transmitted through the phase shift film 30 and light having a representative wavelength transmitted through the transparent substrate 20 only. That is, when the exposed light is a composite light containing light in a wavelength range of 313 nm to 436 nm, the phase shift film 30 has the above-mentioned phase difference with respect to light of a representative wavelength contained in the wavelength range. For example, when the exposed light is a combination of i-rays, h-rays, and g-rays, the phase shift film 30 has the above-described phase difference for any of the i-rays, h-rays, and g-rays.
The phase difference can be measured using a phase shift amount measuring device or the like.

The phase shift film 30 may be composed of a plurality of layers, or may be composed of a single layer. The phase shift film 30 composed of a single layer is difficult to form an interface in the phase shift film 30 and is easy to control the cross-sectional shape, which is preferable in this respect. On the other hand, a phase shift film 30 composed of a plurality of layers is preferable in terms of film formation ease and the like.
In addition, if the film stress of the phase shift film 30 is 0.35 GPa or less, it can be performed by setting the etching rate to be able to end by wet etching before being affected by the immersion with the interface of the etching mask film 40. The phase-etching film has a relatively fast etching rate and is formed into a cross-sectional shape that can fully exert the effect of phase-shifting, which is preferable in this respect. The film stress of the phase shift film 30 is preferably 0.2 GPa or more from the viewpoint of chemical resistance. From the viewpoint of the cross-sectional shape and chemical resistance of the phase shift film pattern, it is more preferable that the film stress of the phase shift film 30 is 0.2 GPa or more and 0.35 GPa or less, and more preferably 0.22 GPa or more and 0.35 GPa or more. the following.

The etching mask film 40 is disposed on the upper side of the phase shift film 30 and includes a material having an etching resistance to an etchant for etching the phase shift film 30. In addition, the etching mask film 40 may have a function of blocking the transmission of the exposed light, and may further have a film surface reflectance of the light incident from the phase shift film 30 side with the phase shift film 30 to be 350 nm to 436 nm. The function of reducing the reflectance of the film surface in a wavelength range of 15% or less. The etching mask film 40 may contain, for example, a chromium-based material. Examples of the chromium-based material include chromium (Cr), and materials containing at least any one of chromium (Cr), oxygen (O), nitrogen (N), and carbon (C). Alternatively, a material containing at least any one of chromium (Cr), oxygen (O), nitrogen (N), and carbon (C), and further containing fluorine (F) may be mentioned. Examples of the material constituting the etching mask film 40 include Cr, CrO, CrN, CrF, CrC, CrCO, CrCN, CrON, CrCON, and CrCONF.
The etching mask film 40 can be formed by a sputtering method.
In addition, if the etching mask film 40 has a columnar structure, a cross-sectional shape of an etching mask film pattern that is patterned by wet etching can be favorably formed. Thereby, the cross-sectional shape of the phase shift film pattern formed by patterning the phase shift film 30 by wet etching using the etching mask film pattern as a mask is further improved, and therefore it is preferable to have a columnar structure. In addition, the columnar structure can be confirmed by observing a cross-section SEM (Scanning Electron Microscope) and confirming the phase shift mask substrate on which the etching mask film 40 is formed. Here, the columnar structure refers to a state where particles of a material constituting the etching mask film have a columnar particle structure extending in a film thickness direction of the etching mask film (the direction in which the particles are stacked).

In the case where the etching mask film 40 has a function of blocking the transmission of the exposed light, the optical density of the exposed light in the portion where the phase shift film 30 and the etching mask film 40 are laminated is preferably 3 or more, more preferably It is 3.5 or more, and more preferably 4 or more.
The optical density can be measured using a spectrophotometer or an OD (Optical Density) meter.

The etch mask film 40 may be composed of a single film having a uniform composition or a plurality of films having different compositions, or may be a single film having a composition that changes continuously due to thickness.

Furthermore, the phase shift mask substrate 10 shown in FIG. 1 is provided with an etching mask film 40 on the phase shift film 30, but for the phase shift film 30 having the etching mask film 40 and the etching mask film 40 The present invention can also be applied to a phase shift mask substrate provided with a resist film thereon.

Next, a method for manufacturing the phase shift mask base 10 in this embodiment will be described. The phase shift mask substrate 10 shown in FIG. 1 is manufactured by performing the following phase shift film formation steps and etching mask film formation steps.
Hereinafter, each step will be described in detail.

1. Phase shift film formation step First, a transparent substrate 20 is prepared. If the transparent substrate 20 is transparent to the exposed light, it may be any glass such as synthetic quartz glass, quartz glass, aluminosilicate glass, soda lime glass, low thermal expansion glass (SiO ₂ -TiO ₂ glass, etc.) and the like. Made of materials.

Next, a phase shift film 30 is formed on the transparent substrate 20 by a sputtering method.
The phase shift film 30 is formed using a sputtering target containing a transition metal and silicon, or a sputtering target containing a transition metal, silicon, and oxygen and / or nitrogen. Sputtering gas atmosphere consisting of at least one inert gas in a group consisting of argon, krypton, and xenon, or a mixture of the above inert gas and a gas containing a gas selected from the group consisting of oxygen, carbon dioxide gas, nitrogen monoxide gas, and nitrogen dioxide gas It is performed in a sputtering gas atmosphere composed of a mixed gas of at least one active gas in the composition group. The active gas may contain nitrogen.

The composition and thickness of the phase shift film 30 are adjusted so that the phase shift film 30 becomes the above-mentioned phase difference and transmittance. The composition of the phase shift film 30 can be controlled by the content ratio of the elements constituting the sputtering target (for example, the content ratio of the transition metal to the silicon content), the composition of the sputtering gas, the flow rate, and the like. The thickness of the phase shift film 30 can be controlled by sputtering power, sputtering time, and the like. When the sputtering apparatus is a continuous sputtering apparatus, the thickness of the phase shift film 30 can be controlled according to the substrate transfer speed. In this way, the content of oxygen in the phase shift film 30 is controlled so that it is 5 atomic% or more and 70 atomic% or less.
In addition, the phase shift film 30 is adjusted according to the degree of vacuum, the sputtering power, the pressure of the sputtering gas, and the like in order to achieve the above-mentioned required film stress.

When the phase shift film 30 is composed of a single film having a uniform composition, the above-described film formation process is performed only once without changing the composition and flow rate of the sputtering gas. In the case where the phase shift film 30 is composed of a plurality of layers with different compositions, each film forming process changes the composition and flow rate of the sputtering gas to perform the above-mentioned film forming process multiple times. The phase shift film 30 can also be formed using targets having different content ratios of the elements constituting the sputtering target. In the case of a single film composition in which the phase shift film 30 continuously changes in thickness direction, the composition and flow rate of the sputtering gas are changed together with the elapsed time of the film formation process, and the above-mentioned film formation process is performed only once. In the case of performing a plurality of film formation processes, the sputtering power applied to the sputtering target can be reduced.

2. Etching mask film forming step After the phase shift film 30 is formed, an etching mask film 40 is formed on the phase shift film 30 by sputtering.
In this way, a phase shift mask substrate 10 can be obtained.

The etching mask film 40 is formed by using a sputtering target containing chromium or a chromium compound (chromium oxide, chromium nitride, chromium carbide, chromium oxynitride, chromium oxynitride, or the like). A sputtering gas atmosphere consisting of at least one of the inert gases in the group consisting of, Neon, Argon, Krypton, and Xenon, or containing a gas selected from the group consisting of helium, neon, argon, krypton, and xenon Mixing at least one inert gas of the group with an active gas containing at least one selected from the group consisting of oxygen, nitrogen, nitrogen monoxide gas, nitrogen dioxide gas, carbon dioxide gas, hydrocarbon gas, and fluorine-based gas The sputtering is performed in a gas atmosphere. Examples of the hydrocarbon gas include methane gas, butane gas, propane gas, and styrene gas.
In addition, the etching mask film 40 can be made into a state having a columnar structure according to the material and composition of the etching mask film 40, the degree of vacuum during sputtering sputtering, the sputtering power, the pressure of the sputtering gas, and the like.

In the case where the etching mask film 40 is composed of a single film having a uniform composition, the above-described film formation process is performed only once without changing the composition and flow rate of the sputtering gas. In the case where the etching mask film 40 is composed of a plurality of layers with different compositions, each of the film forming processes changes the composition and flow rate of the sputtering gas to perform the above-mentioned film forming processes a plurality of times. In the case of etching a single film composition in which the composition of the photomask film 40 continuously changes due to the thickness direction, the composition and flow rate of the sputtering gas are changed together with the elapsed time of the film formation process, and the above film formation process is performed only once.

Furthermore, the phase shift mask substrate 10 shown in FIG. 1 is provided with an etching mask film 40 on the phase shift film 30. Therefore, an etching mask film forming step is performed when the phase shift mask substrate 10 is manufactured. In addition, when manufacturing a phase shift mask substrate having an etching mask film 40 on the phase shift film 30 and a resist film on the etching mask film 40, the etching mask is formed after the etching mask film forming step. A resist film is formed on the film 40.

The phase shift mask substrate 10 of this embodiment 1 contains transition metal, silicon, oxygen, and nitrogen, and the content of oxygen is 5 atomic% or more and 70 atomic% or less, and the ratio of the transition metal to silicon is 1: 1.5 or more. In addition, the phase shift film 30 is configured such that the film stress is 1: 6 or less and the film stress is 0.35 GPa or less. Thereby, before being affected by the immersion of the etching solution at the interface between the phase shift film 30 and the etching mask film 40, the patterning of the phase shift film by wet etching can be ended as set to end Generally, when the etching mask film pattern is used as a mask to form a phase shift film pattern by wet etching, the phase mask film pattern is reliably formed without removing the etching mask film pattern in the middle. Furthermore, the phase shift film pattern can be formed into a cross-sectional shape that can fully exhibit the phase shift effect, and a phase shift mask having a phase shift film pattern having excellent CD uniformity can be obtained. Moreover, in the case of the phase shift mask, when the etching mask film pattern remains on the phase shift film pattern, the influence of reflection from the protective film or the display device substrate attached to the phase shift mask can be suppressed. In addition, the phase shift mask substrate 10 of this first embodiment can form a phase shift film pattern with a good cross-sectional shape, a small CD deviation, and a high transmittance by wet etching. Therefore, it is possible to obtain a phase shift mask substrate capable of manufacturing a phase shift mask capable of transferring a highly fine phase shift film pattern with high accuracy.

Embodiment 2.
In the second embodiment, a method for manufacturing a phase shift mask will be described.

FIG. 2 is a schematic view showing a method of manufacturing a phase shift mask.
The method of manufacturing the phase shift mask shown in FIG. 2 is a method of manufacturing a phase shift mask using the phase shift mask substrate 10 shown in FIG. 1, which includes the following steps: forming a resistance on the phase shift mask substrate 10 described above. Etch film; forming a resist film pattern 50 by drawing and developing a desired pattern on the resist film (first resist film pattern forming step), using the resist film pattern 50 as a mask, Patterning the etch mask film 40 to form an etch mask film pattern 40a (the first etch mask film pattern forming step); and using the etch mask film pattern 40a as a mask, and using the phase shift film 30 by A phase shift film pattern 30a is formed on the transparent substrate 20 by wet etching (phase shift film pattern forming step). Furthermore, it further includes a second resist film pattern forming step and a second etching mask film pattern forming step.
Hereinafter, each step will be described in detail.

1. First resist film pattern forming step In the first resist film pattern forming step, first, a resist film is formed on the etching mask film 40 of the phase shift mask substrate 10 of Embodiment 1. The resist material used is not particularly limited. For example, it suffices that it is sensitive to laser light having any wavelength selected from the wavelength range of 350 nm to 436 nm described below. The resist film may be either a positive type or a negative type.
Thereafter, a desired pattern is drawn on the resist film using laser light having any wavelength selected from a wavelength region of 350 nm to 436 nm. The pattern drawn on the resist film is a pattern formed on the phase shift film 30. Examples of the pattern drawn on the resist film include a line and gap pattern or a hole pattern.
Thereafter, the resist film is developed with a specific developing solution, and as shown in FIG. 2 (a), a first resist film pattern 50 is formed on the etching mask film 40.

2. First etching mask film pattern forming step In the first etching mask film pattern forming step, first, the etching mask film 40 is etched with the first resist film pattern 50 as a mask to form a first etching light. Cover film pattern 40a. The etching mask film 40 is formed of a chromium-based material containing chromium (Cr). The etching solution for etching the etching mask film 40 is not particularly limited as long as it can selectively etch the etching mask film 40. Specific examples include an etching solution containing ceric ammonium nitrate and perchloric acid.
Thereafter, as shown in FIG. 2 (b), the first resist film pattern 50 is peeled off using a resist stripping solution or by ashing. Depending on circumstances, the next phase shift film pattern forming step may be performed without peeling the first resist film pattern 50.

3. Phase shift film pattern forming step In the first phase shift film pattern forming step, the phase shift film 30 is etched with the first etch mask film pattern 40a as a mask, as shown in FIG. 2 (c), forming a phase Film transfer pattern 30a. Examples of the phase shift film pattern 30a include a line and gap pattern or a hole pattern. The etching solution for etching the phase shift film 30 is not particularly limited as long as it can selectively etch the phase shift film 30. Examples thereof include an etching solution containing ammonium fluoride, phosphoric acid, and hydrogen peroxide, and an etching solution containing ammonium hydrogen fluoride and hydrogen chloride.

4. Second resist film pattern forming step In the second resist film pattern forming step, first, a resist film covering the first etching mask film pattern 40 a is formed. The resist material used is not particularly limited. For example, it suffices that it is sensitive to laser light having any wavelength selected from the wavelength range of 350 nm to 436 nm described below. The resist film may be either a positive type or a negative type.
Thereafter, a desired pattern is drawn on the resist film using laser light having any wavelength selected from a wavelength region of 350 nm to 436 nm. The pattern drawn on the resist film is a light-shielding strip pattern that shields the outer peripheral area of the area where the pattern is formed on the phase-shift film 30 and a light-shielding strip pattern that shields the central portion of the phase-shift film pattern. Furthermore, the pattern drawn on the resist film may be a pattern without a light-shielding belt pattern that shields the central portion of the phase-shift film pattern 30a according to the transmittance of the phase-shift film 30 to the exposed light.
Thereafter, the resist film is developed with a specific developing solution, and as shown in FIG. 2 (d), a second resist film pattern 60 is formed on the first etching mask film pattern 40 a.

5. Second etching mask film pattern forming step In the second etching mask film pattern forming step, the second etching film pattern 60 is used as a mask to etch the first etching mask film pattern 40a, as shown in FIG. 2 ( As shown in e), a second etching mask film pattern 40b is formed. The first etching mask film pattern 40a is formed of a chromium-based material containing chromium (Cr). The etching solution for etching the first etching mask film pattern 40a is not particularly limited as long as it can selectively etch the first etching mask film pattern 40a. For example, an etching solution containing ammonium cerium nitrate and perchloric acid may be mentioned.
Thereafter, the second resist film pattern 60 is peeled using a resist stripping solution or by ashing.
Thus, a phase shift mask 100 can be obtained.
Furthermore, in the above description, the case where the etching mask film 40 has a function of blocking the transmission of the exposed light has been described, but the etching mask film 40 has only a hard mask when the phase shift film 30 is etched. In the case of functions, in the above description, the second resist film pattern forming step and the second etching mask film pattern forming step are not performed, and the first etching mask film pattern is peeled off after the phase shift film pattern forming step, so that A phase shift mask 100 is made.

According to the manufacturing method of the phase shift mask of the second embodiment, since the phase shift mask base of the first embodiment is used, a phase shift film pattern with a good cross-sectional shape and small CD deviation can be formed. Therefore, it is possible to manufacture a phase shift mask capable of transferring a highly fine phase shift film pattern with high accuracy. The phase shift mask manufactured in this way can cope with the miniaturization of line and gap patterns or contact holes.

Embodiment 3.
In the third embodiment, a method for manufacturing a display device will be described. The display device is a step of performing a phase shift mask 100 manufactured using the above-described phase shift mask substrate 10 or using a phase shift mask 100 manufactured by the above-described method of manufacturing the phase shift mask 100 Step), and a step (pattern transfer step) of exposing and transferring the transfer pattern onto the resist film on the display device (pattern transfer step).
Hereinafter, each step will be described in detail.

1. Mounting step In the mounting step, the phase shift mask manufactured in Embodiment 2 is placed on a mask stage of an exposure apparatus. Here, the phase shift mask is disposed so as to face the resist film formed on the display device substrate through the projection optical system of the exposure device.

2. Pattern transfer step In the pattern transfer step, the phase shift mask 100 is irradiated with the exposed light, and the phase shift film pattern is transferred to a resist film formed on the display device substrate. The light to be exposed is a composite light including a plurality of wavelengths of light selected from a wavelength range of 365 nm to 436 nm, or a wavelength range selected from a wavelength range of 365 nm to 436 nm by a filter or the like Monochrome light. For example, the exposed light is i-ray, h-ray, and g-ray composite light or i-ray monochromatic light. If composite light is used as the light for exposure, the light intensity of the exposure can be increased and the output can be increased, so the manufacturing cost of the display device can be reduced.

According to the manufacturing method of the display device of the third embodiment, it is possible to manufacture a high-definition display device capable of suppressing CD errors and having high resolution, fine line and gap patterns, or contact holes.
[Example]

Confirmation of film stress, etching rate, and cross-sectional shape of phase-shift film pattern In order to confirm film stress, etching rate, and cross-sectional shape of phase-shift film pattern, the following experiments were performed.
First, prepare a transparent substrate 20 composed of 6025 size (152 mm × 152 mm) synthetic quartz glass substrates whose two main surfaces are mirror-polished. The transparent substrate 20 is covered with 5 × 5 pieces in vertical and horizontal directions and transferred into continuous sputtering. Device. The continuous sputtering apparatus is provided with a first chamber for forming a phase shift film 30 and second, third, and fourth chambers for forming an etching photomask film 40.
A specified sputtering power is applied to the molybdenum silicide target (Mo: Si = 1: 4) disposed in the first chamber, and a mixed gas of Ar gas, N ₂ gas, and CO ₂ gas is introduced into the first chamber while being transferred. The transparent substrate 20 forms a phase shift film 30 including a molybdenum silicide-based material (MoSiONC) containing Mo, Si, O, N, and C on the transparent substrate 20 when the transparent substrate 20 passes near the molybdenum silicide target. Furthermore, the vacuum degree, sputtering power, and pressure of the sputtering gas in the first chamber are appropriately adjusted, and the seven types of phase shift films 30 having different film stresses are formed on the transparent substrate 20.
The film stress was calculated using UltraFLAT 200M (manufactured by Corning Tropel Co., Ltd.) for each phase-shifted film 30 that had been formed, by measuring the change in flatness.
In addition, the composition analysis of seven types of phase shift films 30 having different film stresses was performed by X-ray photoelectron spectroscopy (XPS). As a result, 7 types (samples 1 to 7) of the phase shift film 30 were uniformly contained in the depth direction of the film, and the average content of each element was Mo: 11 atomic%, Si: 25 atomic%, and O: 34 atoms. %, N: 18 atomic%, C: 12 atomic%, the ratio of Mo to Si is 1: 2.3, and the content rate of oxygen contained in the phase shift film 30 is greater than the content rate of nitrogen.

Next, the transparent substrate 20 with the phase shift film 30 is introduced into the second chamber, and a mixed gas of argon (Ar) gas and nitrogen (N ₂ ) gas is introduced with the second chamber set to a specific vacuum degree. _{(Ar: 65 sccm, N 2} : 15 sccm). Then, a sputtering power of 1.5 kW was applied to a sputtering target containing chromium, and a chromium nitride (CrN) (film thickness: 15 nm) containing chromium and nitrogen was formed on the phase shift film 30 by reactive sputtering. Next, a mixed gas (30 sccm) of argon (Ar) gas and methane (CH ₄ : 4.9%) gas was introduced under a condition of a specific vacuum degree in the third chamber, and applied to a sputtering target containing chromium. With a sputtering power of 8.5 kW, chromium carbides (CrC) (film thickness 60 nm) containing chromium and carbon are formed on CrN by reactive sputtering. Finally, in a state where the fourth chamber is set to a specific vacuum degree, a mixed gas of argon (Ar) gas and methane (CH ₄ : 5.5%) gas, and nitrogen (N ₂ ) gas and oxygen (O ₂ ) are introduced. Gas mixture (Ar + CH ₄ : 30 sccm, N ₂ : 8 sccm, O ₂ : 3 sccm), a sputtering power of 2.0 kW was applied to a chromium-containing sputtering target, and reactive sputtering was performed on CrC. Forms chromium oxynitride (CrCON) (film thickness 30 nm) containing chromium, carbon, oxygen, and nitrogen. As described above, the etching mask film 40 having a laminated structure of a CrN layer, a CrC layer, and a CrCON layer is formed on the phase shift film 30. Furthermore, a cross-sectional SEM observation of the phase shift mask base 10 on which the phase shift film 30 and the etching mask film 40 were formed on the transparent substrate 20 was performed, and it was confirmed that the etching mask film 40 had a columnar structure.

Then, a photoresist is coated on the etching mask film 40 by using a resist coating device, and then a heating and cooling step is performed to form a photoresist film having a film thickness of 520 nm. After that, the photoresist film was drawn using a laser drawing device. After the development and washing steps, the line and gap patterns with a line pattern width of 1.8 μm and the gap pattern width of 1.8 μm were formed on the etch mask film. Etch pattern.
Thereafter, using the resist film pattern as a mask, the etching mask film is wet-etched with a chromium etchant containing cerium ammonium nitrate and perchloric acid to form an etching mask film pattern 40a.
Thereafter, using the etching mask film pattern 40a as a mask, the phase shift film 30 was wet-typed with a molybdenum silicide etching solution (temperature: 22 ° C.) diluted with pure water from a mixed solution of ammonium hydrogen fluoride and hydrogen peroxide. Etching forms a phase shift film pattern 30a.

Thereafter, after the resist film pattern is peeled off with a resist stripping solution, finally, the mask film pattern 40a is peeled off and etched with a chromium etchant.
In this way, a phase shift film pattern 30 a is formed on the transparent substrate 20. The cross section of the obtained phase shift film pattern 30a was observed with a scanning electron microscope. The cross-sectional shape of the phase shift film pattern is defined based on the angle formed by the upper surface and the side where the upper surface and the side meet (the upper side) and the side and the lower surface where the side and the lower surface meet (the lower side). The cross-sectional shapes of samples 1 to 7 were evaluated.
Table 1 shows the results of the film stress of the phase shift film 30 of samples 1 to 7, the etching speed on the molybdenum silicide etchant, and the cross-sectional shape.

【Table 1】 As shown in Table 1, it was confirmed that as the film stress of the phase shift film 30 becomes smaller, the etching rate with respect to the molybdenum silicide etching solution becomes faster. It was confirmed that by setting the film stress of the phase shift film 30 to 0.45 GPa or less, the formation of the phase shift film pattern 30a was completed before the immersion of the etching solution in the interface between the phase shift film 30 and the etching mask film 40, Therefore, the phase shift film pattern can be formed without peeling the etching mask film pattern in the middle. In addition, it was confirmed that by setting the film stress of the phase shift film 30 to 0.35 GPa or less, the cross-sectional shape of the phase shift film pattern obtained was 45 ° or more, and it was fully exhibited by performing the following overetching. Section shape of the phase shift effect. In addition, although the cross-sectional shape becomes good as the film stress becomes smaller, the sample 7 (reference example) in which the film stress of the phase shift film 30 does not reach 0.2 GPa was performed using a sulfuric acid hydrogen peroxide mixture or an ammonia water hydrogen peroxide mixture. The results of the chemical resistance evaluation cannot be said to be good. From the above results, in order to make the cross-sectional shape of the phase shift film pattern formed by wet etching good, the film stress of the phase shift film 30 is preferably 0.35 GPa or less, and the chemical resistance of the phase shift film is further improved. From the viewpoint, the film stress of the phase shift film 30 is preferably 0.2 GPa or more and 0.35 GPa or less.

Examples 1 to 3.
A. Phase shift mask substrate and manufacturing method thereof To manufacture the phase shift mask substrate of Example 1, first, a 1214 size (1220 mm × 1400 mm) synthetic quartz glass substrate is prepared as the transparent substrate 20.

Thereafter, the main surface of the synthetic quartz glass substrate is mounted on a tray (not shown) with the main surface facing downward, and is carried into the first chamber of the continuous sputtering apparatus.
A phase shift film 30 was formed on the main surface of the transparent substrate 20 by sputtering according to the film formation conditions of the above-mentioned sample 4 (Example 1), sample 5 (Example 2), and sample 6 (Example 3). .
Next, in the same manner as above, a phase-shifting mask base 10 having an etched mask film 40 having a laminated structure of a CrN layer, a CrC layer, and a CrCON layer formed on the phase-shifting film 30 is obtained.

With respect to the obtained phase-shifting film 30 of the phase-shifting mask base 10, transmittance and phase difference were measured by MPM-100 manufactured by Lasertec. In the measurement of the transmittance and phase difference of the phase shift film 30, a substrate with a phase shift film (a dummy substrate) with a phase shift film 30 formed on the main surface of a synthetic quartz glass substrate manufactured on the same tray was used (a dummy substrate). ). The transmittance and phase difference of the phase shift film 30 are measured before the substrate (dummy substrate) with the phase shift film is taken out from the chamber before the etching mask film 40 is formed. As a result, the transmittance was 22.1% (wavelength: 365 nm) and the phase difference was 161 degrees (wavelength: 365 nm).
In addition, for each phase shift film 30, the change in flatness was measured using UltraFLAT 200M (manufactured by Corning Tropel Co.), and the film stress was calculated. The results were found to be the same as the evaluation results in Table 1. In addition, the amount of change in transmittance and change in phase difference of the chemical solution (sulfuric acid hydrogen peroxide mixture, ammonia water hydrogen peroxide mixture, and ozone water) used in the cleaning of the phase shift mask by this phase shift film 30 are relatively small. Small, and has high chemical resistance, washing resistance.
In addition, the film stress of the phase shift film 30 is measured by a flatness measuring device that can measure the flatness of a large glass substrate or a large phase shift mask base. The flatness of the substrate with the phase shift film on which the phase shift film 30 was formed was measured, and the change in flatness was measured to calculate the film stress. As a result, it was confirmed that the results are the same as the evaluation results in Table 1.

In addition, about the obtained phase shift mask substrate, the reflectance and optical density of the film surface were measured with a spectrophotometer SolidSpec-3700 manufactured by Shimadzu Corporation. The film surface reflectance of the phase shift mask substrate (etching mask film 40) is 8.3% (wavelength: 436 nm), and the optical density OD is 4.0 (wavelength: 436 nm). It can be seen that the etching mask film functions as a light-shielding film having a small reflectance on the film surface.

B. Phase-shifting reticle and manufacturing method thereof In order to manufacture the phase-shifting reticle 100 using the phase-shifting reticle substrate 10 manufactured in the manner described above, first, an anti-reflection film 40 on the phase-shifting reticle substrate 10 is used. The resist coating device coats a photoresist film.
After that, a photoresist film with a film thickness of 520 nm was formed through the heating and cooling steps.
After that, the photoresist film was drawn using a laser drawing device. After the development and washing steps, the line and gap patterns with a line pattern width of 1.8 μm and the gap pattern width of 1.8 μm were formed on the etch mask film. Etch pattern.

Thereafter, using the resist film pattern as a mask, the etching mask film is wet-etched with a chromium etchant containing cerium ammonium nitrate and perchloric acid to form a first etching mask film pattern 40a.

Thereafter, the first etching mask film pattern 40a is used as a mask, and the phase shift film 30 is wet-etched with a molybdenum silicide etching solution diluted with a mixed solution of ammonium hydrogen fluoride and hydrogen peroxide with pure water to form a phase. Film transfer pattern 30a.
Thereafter, the resist film pattern is peeled.

Thereafter, a photoresist film is applied so as to cover the first etching mask film pattern 40a using a resist coating device.
After that, a photoresist film with a film thickness of 520 nm was formed through the heating and cooling steps.
Thereafter, a photoresist film is drawn using a laser drawing device, and a second resist film pattern 60 for forming a light-shielding band is formed on the first etching mask film pattern 40a through development and washing steps.

Thereafter, using the second resist film pattern 60 as a mask, the first etching mask film pattern 40a formed in the transfer pattern formation region was wet-typed with a chromium etchant containing cerium ammonium nitrate and perchloric acid. Etching.
Thereafter, the second resist film pattern 60 is peeled.

In this way, a phase-shielding film pattern 30a is formed on the transparent substrate 20 in the transfer pattern formation region, and a light-shielding structure including a laminated structure including the phase-shift film pattern 30a and the etching mask film pattern 40b is formed outward from the transfer pattern formation region. Strip of phase shift mask 100.

The cross-sectional shape of the phase shift film pattern of the obtained phase shift mask was observed with a scanning electron microscope.

The cross-sectional shape (angle) of the phase-shifting film pattern formed on the phase-shifting photomasks of Examples 1 to 3 is the same as the result of Table 1 above, and all meet the 45% or more of the lower limit of the cross-section control by overetch . Therefore, when forming the phase shift film patterns of Examples 1 to 3, by performing the etching, it is possible to obtain exposure light containing light in a wavelength range of 300 nm to 500 nm, and more specifically, i A phase-shifting mask having excellent phase-shifting effect in the exposure light of the combined light of ray, h-ray and g-ray.

The CD deviation of the phase shift film pattern of the phase shift mask was measured by SIR8000 manufactured by Seiko Electronics Nanotechnology. The measurement of the CD deviation is performed on an area of 1100 mm × 1300 mm other than the peripheral area of the substrate at 11 × 11 locations. The CD deviation is the magnitude of deviation from the target line and gap pattern (width of line pattern: 1.8 μm, width of gap pattern: 1.8 μm). In Examples 1 to 3 and Comparative Example 1, the same apparatus was used for the measurement of the CD deviation.
A CD deviation of 0.098 μm is better.
Therefore, when the phase shift masks of Examples 1 to 3 are set on the mask stage of the exposure device, and the resist film on the display device is subjected to exposure transfer, it can be asserted that the transfer can be achieved with high accuracy. Fine pattern of 2.0 μm.

Comparative Examples 1 to 3.
In order to manufacture the phase shift mask substrates of Comparative Examples 1 to 3, a synthetic quartz glass substrate having a size of 1214 (1220 mm × 1400 mm) was prepared as a transparent substrate in the same manner as in Examples 1 to 3.
A phase shift film 30 was formed on the main surface of the transparent substrate 20 by sputtering under the film forming conditions of the above-mentioned sample 1 (comparative example 1), sample 2 (comparative example 2), and sample 3 (comparative example 3).
Then, in the same manner as described above, a phase shift mask substrate 10 of an etch mask film 40 having a laminated structure of a CrN layer, a CrC layer, and a CrCON layer formed on the phase shift film 30 is obtained. For each of the obtained phase shift films 30, the change in flatness was measured using UltraFLAT 200M (manufactured by Corning Tropel Co.), and the film stress was calculated. The results are the same as the evaluation results in Table 1. In addition, the amount of change in transmittance and change in phase difference of the chemical solution (sulfuric acid hydrogen peroxide mixture, ammonia water hydrogen peroxide mixture, and ozone water) used in the cleaning of the phase shift mask by this phase shift film 30 are relatively Small, and has high chemical resistance, washing resistance.
Then, a phase shift mask was produced by the same method as in Examples 1 to 3.
The cross-sectional shape of the phase shift film pattern of the obtained phase shift mask was observed with a scanning electron microscope. As a result, in Comparative Example 1, the etching mask film pattern was peeled before the phase shift film pattern was formed, and the phase shift film pattern could not be formed. In Comparative Example 2, the mask film pattern was not peeled before the phase shift film pattern was formed, but the cross-sectional shape (angle) of the obtained phase shift film pattern became 10 °, which is the same as the result in Table 1 above. It is 45 degrees lower than the lower limit of the cross-sectional control by over-etching.
Therefore, with the obtained phase shift mask, it is impossible to expose light containing light in a wavelength range of 300 nm to 500 nm, and more specifically, to include i-ray, h-ray, and g-ray composite light. A sufficient phase shift effect is obtained in the exposed light.
The CD deviation of the phase shift film pattern of Comparative Example 2 was 0.313 μm, and the CD deviation of the phase shift film pattern of Comparative Example 3 was 0.283 μm.

Therefore, when the phase shift masks of Comparative Examples 1 to 3 are set on the mask stage of an exposure device and the resist film on the display device is subjected to exposure transfer, it is expected that a fine pattern less than 2.0 μm cannot be transferred. .

Example 4.
In order to manufacture the phase shift mask substrate of Example 4, as in Examples 1 to 3, a 1214 size (1220 mm × 1400 mm) synthetic quartz glass substrate was prepared as a transparent substrate.
Then, on the main surface of the transparent substrate 20, a phase shift film 30 is formed by sputtering in accordance with the following film forming conditions.
A specific sputtering power is applied to a molybdenum silicide target (Mo: Si = 1: 9) disposed in the first chamber of the continuous sputtering device, while Ar gas, helium (He) gas, and nitrogen (N ₂ ) are applied. A mixed gas of gas (Ar: 18 sccm, He: 50 sccm, N ₂ : 13 sccm) is introduced into the first chamber to transport the transparent substrate 20, and when the transparent substrate 20 passes near the molybdenum silicide target, the transparent substrate 20 is aligned. A phase shift film 30 including a molybdenum silicide-based material (MoSiON) containing Mo, Si, O, and N is formed.
The film stress is calculated in the same manner as in Example 1 by measuring the flatness change for each phase-shifted film 30 that has been formed. The film stress of the phase shift film 30 is 0.22 Pa. Furthermore, the amount of change in the transmittance and the amount of phase difference of the chemical liquids (sulfuric acid hydrogen peroxide mixture, ammonia water hydrogen peroxide mixture, and ozone water) used in the cleaning of the phase shift mask by this phase shift film 30 are relatively small. Small, and has high chemical resistance, washing resistance.
The composition of the phase shift film 30 is analyzed by X-ray photoelectron spectroscopy (XPS). As a result, the phase shift film 30 is uniformly contained in the depth direction of the film. The average content of each element is Mo: 8 atomic%, Si: 40 atomic%, O: 6 atomic%, and N: 46 atomic%. The ratio of Si is Mo: Si = 1: 5.
Next, the transparent substrate 20 with the phase shift film 30 is introduced into the second chamber, and an etching mask film 40 having a laminated structure of a CrN layer, a CrC layer, and a CrCON layer is formed on the phase shift film 30 in the same manner as in the above embodiment. .
With respect to the obtained phase-shifting film 30 of the phase-shifting mask base 10, the transmittance and phase difference were measured by MPM-100 manufactured by Lasertec Corporation in the same manner as in the above-mentioned embodiment. The transmittance of the phase shift film 30 is 27.0% (wavelength 405 nm), and the phase difference is 178 degrees (wavelength: 405 nm).
The cross-sectional SEM observation of the phase-shifting mask base 10 on which the phase-shifting film 30 and the etching mask film 40 were formed on the transparent substrate 20 was performed in the same manner as in the above-mentioned embodiment, and it was confirmed that the etching-mask film 40 had a columnar structure.
Then, as in the above-mentioned embodiment, the phase shift mask 100 is manufactured using the phase shift mask substrate 10.
The cross-sectional shape of the phase shift film pattern of the obtained phase shift mask was observed with a scanning electron microscope. FIG. 3 is a sectional photograph of a phase shift mask of Embodiment 4. FIG.
As shown in FIG. 3, the cross-sectional shape (angle) of the phase shift film pattern formed on the phase shift mask of Example 4 is 74 degrees. Thereby, it is possible to obtain an exposure light containing light in a wavelength range of 300 nm to 500 nm, more specifically, an exposure light containing a composite light of i-rays, h-rays, and g-rays. Phase shift mask for shift effect.
Furthermore, as in the above examples, the CD deviation of the phase shift film pattern of the phase shift mask was measured, and it was found that a CD deviation of 0.092 μm is better.
Therefore, when the phase shift mask of Example 4 is set on the mask stage of an exposure device, and the resist film on the display device is subjected to exposure transfer, it can be asserted that the transfer of less than 2.0 μm can be performed with high accuracy. Fine pattern.
Furthermore, in the above embodiment, the case where molybdenum is used as the transition metal has been described, but in the case of other transition metals, the same effect as the above can be obtained.
Moreover, in the said embodiment, although the example of the phase shift mask base for display device manufacture, and the phase shift mask for display device manufacture was demonstrated, it is not limited to this. The phase shift reticle substrate and the phase shift reticle of the present invention can also be applied to semiconductor device manufacturing, MEMS (Microelectromechanical System, microelectromechanical system) manufacturing, printed substrates, and the like.
In the above-mentioned embodiment, the example in which the size of the transparent substrate is 1214 (1220 mm × 1400 mm) has been described, but it is not limited to this. In the case of a phase shift mask substrate for display device manufacturing, a large size transparent substrate may be used, and the size of the transparent substrate is 300 mm or more on one side. The size of the transparent substrate used in the phase shift mask base for manufacturing a display device is, for example, 330 mm × 450 mm or more and 2280 mm × 3130 mm or less.
In the case of a phase shift mask substrate for semiconductor device manufacturing, MEMS manufacturing, and printed circuit boards, a small-size transparent substrate can be used, and the size of the transparent substrate is 9 inches or less on one side. The size of the transparent substrate used in the phase shift mask base of the above-mentioned application is, for example, 63.1 mm × 63.1 mm or more and 228.6 mm × 228.6 mm or less. Generally, 6025 size (152 mm × 152 mm) or 5009 size (126.6 mm × 126.6 mm) is used for semiconductor manufacturing and MEMS manufacturing, and 7012 size (177.4 mm × 177.4 mm) or 9012 size (228.6) is used for printed circuit board systems. mm × 228.6 mm).

10‧‧‧Phase shift mask substrate

20‧‧‧ transparent substrate

30‧‧‧ phase shift film

30a‧‧‧phase shift film pattern

40‧‧‧ etching mask film,

40a‧‧‧The first etching mask film pattern

40b‧‧‧Second etching mask film pattern

50‧‧‧The first resist film pattern

60‧‧‧Second resist pattern

100‧‧‧phase shift mask

FIG. 1 is a schematic diagram showing a film configuration of a base of a phase shift mask.

2 (a) to (e) are schematic diagrams showing manufacturing steps of a phase shift mask.

FIG. 3 is a sectional photograph of a phase shift mask of Embodiment 4. FIG.

Claims (10)

A phase shift mask substrate, characterized in that: it is provided with a phase shift film on a transparent substrate and an etching mask film on the phase shift film; and The phase shift mask substrate is used to form an etching mask film pattern with a specific pattern on the etching mask film as a mask, and the phase shift film is formed on the transparent substrate by wet etching to form a phase shift film. The original version of the phase shift mask of the pattern; The phase shift film contains transition metals, silicon, oxygen, and nitrogen; The content of oxygen contained in the phase shift film is 5 atomic% or more and 70 atomic% or less; The ratio of transition metal to silicon contained in the phase shift film is 1: 1.5 or more and 1: 6 or less; The film stress of the phase shift film is 0.35 GPa or less. For example, the phase shift mask substrate of claim 1, wherein the content of nitrogen in the phase shift film is 2 atomic% or more and 60 atomic% or less. For example, the phase shift mask substrate of claim 1 or 2, wherein the content rate of oxygen contained in the phase shift film is greater than the content rate of nitrogen. For example, the phase shift mask substrate of claim 1 or 2, wherein the phase shift film is composed of a plurality of layers or a single layer. The phase shift mask substrate according to claim 1 or 2, wherein the etching mask film comprises a chromium-based material. The phase shift mask substrate according to claim 1 or 2, wherein the etching mask film has a columnar structure. The phase shift mask substrate according to claim 1 or 2, wherein the etching mask film contains at least any one of nitrogen, oxygen, and carbon. For example, the phase shift mask substrate of claim 1 or 2, wherein the transparent substrate is a rectangular substrate, and the length of the short side of the transparent substrate is 300 mm or more. A method for manufacturing a phase-shifting photomask is characterized by including the following steps: Prepare the phase shift mask substrate of any of claims 1 to 8; Forming a resist film on the phase shift mask substrate; The resist film pattern is formed by drawing and developing a desired pattern on the resist film, and using the resist film pattern as a mask, the etching mask film is patterned by wet etching to form the resist film. Etching the mask film pattern; and The etching mask film pattern is used as a mask, and the phase shift film is wet-etched on the transparent substrate to form a phase shift film pattern. A method of manufacturing a display device, comprising the steps of using a phase shift mask manufactured using the phase shift mask substrate of any one of claims 1 to 8, or using phase shift light by claim 9 The phase shift mask manufactured by the manufacturing method of the mask exposes the transfer pattern to a resist film on the display device.