TW201903512A - Phase shift mask blank and method for manufacturing phase shift mask using the same and pattern transfer method - Google Patents

Abstract

A phase shift mask blank capable of manufacturing a phase shift mask capable of transferring a high-precision phase shift film pattern with high precision is provided. The phase shift film includes: a lower layer having a function of adjusting a reflectance with respect to light incident from a transparent substrate side; and an upper layer disposed on the upper side of the lower layer and having a function of adjusting transmittance and retardation of an exposure light. The phase shift film has predetermined optical properties with respect to transmittance and retardation with respect to the exposure light. The phase shift film has a reflectance for light in a wavelength range of 365 nm to 436 nm incident from the transparent substrate side is more than 20%, and a fluctuation range of reflectance for light in a wavelength range of 365 nm to 436 nm incident from the transparent substrate side is 10% or less.

Description

Phase shift mask base and method of manufacturing phase shift mask using same, and pattern transfer method

The present invention relates to a phase shift mask substrate, a method of manufacturing a phase shift mask using the same, and a pattern transfer method.

In recent years, with the high resolution and high definition of display devices such as FPD (Flat Panel Display), a phase shift mask for manufacturing a display device having a fine pattern has been sought. In the conventional conventional phase shift mask substrate used for the manufacture of a phase shift mask for manufacturing a display device, the substrate for a photomask made of synthetic quartz glass (hereinafter sometimes referred to as a synthetic quartz glass substrate) is used. A phase shift film is formed, and a light shielding film is formed on the phase shift film. When the phase shift film contains MoSiN, the transmittance of the i-ray used as the light for exposure is about 5%, and the reflectance of the light incident on the substrate side from the mask is 11%. Patent Document 1 describes a phase shift mask for manufacturing an LSI (Large Scale Integration) and a phase shift mask substrate used in the manufacture of the same. The phase shift mask base described in Patent Document 1 includes a light-transmitting substrate, a highly reflective material layer disposed on the light-transmitting substrate, a phase inversion layer disposed on the highly reflective material layer, and a phase inversion layer. Light blocking layer. The light transmissive substrate contains quartz. The highly reflective material layer has a reflectance of 20% to 90% with respect to the amount of light irradiated. The highly reflective material layer comprises bismuth (Si), molybdenum (Mo), tantalum (Ta), zirconium (Zr), aluminum (Al), titanium (Ti), platinum (Pt), ruthenium (Ru), chromium (Cr). And at least one of tin (Sn). The highly reflective material layer may additionally contain any one of oxygen (O) and nitrogen (N). The phase inversion layer contains molybdenum molybdenum (MoSi), molybdenum nitride (MoSiN) or hafnium oxide (SiO ₂ ). The light-shielding layer contains chromium (Cr). In addition, in recent years, with the increase in the size of display devices such as FPD, the substrate for a photomask has also been increased in size. When the substrate for the reticle is increased in size, the thermal deformation of the reticle substrate due to absorption of the exposed light becomes large, and the position of the pattern formed in the reticle changes. Therefore, it is desirable to form a substrate for a photomask using a material having little thermal expansion. Patent Document 2 describes a substrate for a photomask comprising a material obtained by adding TiO ₂ to quartz glass (hereinafter sometimes referred to as a TiO ₂ -SiO ₂ glass substrate). The substrate has a small coefficient of thermal expansion. Further, in Patent Document 3 describes a TiO ₂ on a glass substrate with a light-shielding film ₂ -SiO formed, and thus the light-shielding film formed on the antireflection film of the photomask substrate and photomask. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Patent Laid-Open No. 2010-152924 (Patent Document 2) Japanese Patent Laid-Open Publication No. 2010-010915 (Patent Document 3) Japanese Patent Laid-Open No. 2010-26398 Bulletin

[Problem to be Solved by the Invention] As described above, the transmittance of the phase shift film used in the conventional conventional phase shift mask substrate is about 5%. If the transmittance is small, there is a concern that in the phase shift mask used in the manufacture of FPDs such as a new generation of organic EL (Electroluminescence) panels, exposure on the phase shift film may occur due to repeated use. The positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film pattern due to absorption of light. The phase shift mask of Patent Document 1 is used for manufacturing an LSI, and therefore the phase shift film pattern is usually formed by dry etching. The phase shift mask of the patent document 1 is used for the manufacture of the LSI, and the reticle used in the manufacture of the semiconductor element is described as a prior art of the cited document 1 (refer to paragraph 0002 of the cited document 1). . In the case of a phase shift mask for manufacturing a display device such as an FPD, the phase shift film pattern is formed by wet etching. When the phase shift film including the highly reflective material layer and the phase inversion layer of Patent Document 1 is patterned by wet etching, the etching speed of the highly reflective material layer and the phase inversion layer is extremely different, and therefore, The cross-sectional shape of the phase shift film pattern or the CD (Cristal Dimension) unevenness is deteriorated. Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide a phase shift mask substrate for manufacturing a phase shift mask and a method of manufacturing a phase shift mask using the same, the phase shift mask substrate can be The absorption of the exposed light on the phase shift film is reduced to suppress the change in position of the phase shift film pattern caused by the thermal expansion of the phase shift film pattern. Further, it is an object of the invention to provide a phase shift mask substrate and a phase shift mask using the same, which can form a phase shift having a good cross-sectional shape and a small CD unevenness by wet etching Membrane pattern. [Means for Solving the Problems] The inventors of the present invention have made an effort to achieve the above object, and have obtained the following findings: at least a lower layer having a function of adjusting a reflectance of light incident on a side from a transparent substrate, and a lower layer disposed on the lower layer Further, the upper layer is configured to adjust the transmittance and phase difference of the light to be exposed, and the phase shift film is formed, and the composition of the material forming the upper layer and the lower layer of the phase shift film is studied, thereby making the phase shift film The reflectance (back surface reflectance) of light in the wavelength region of 365 nm to 436 nm incident from the side of the transparent substrate exceeds 20%, which can reduce the absorption of the exposed light on the phase shift film, and can suppress the phase shift film pattern. The position changes. In particular, it has been found that when the light to be exposed is a composite light containing light of a plurality of wavelengths selected from a wavelength region of 365 nm to 436 nm, in addition to the optical characteristics of the back reflectance of the phase shift film By setting the fluctuation range of the reflectance (back surface reflectance) of the phase shifting film to the wavelength region of 365 nm to 436 nm incident from the transparent substrate side to 10% or less, the exposure on the phase shift film can be reduced. The absorption of light can suppress the positional change of the phase shift film pattern. Further, the following findings have been obtained: the composition of the material formed to constitute the upper layer and the lower layer of the phase shift film is studied, whereby the upper layer and the lower layer can be etched using the same etching liquid when patterning the phase shift film. Further, the ratio of the etching rate of the lower layer to the etching rate of the upper layer is more than 1 and not more than 10, whereby a phase shift film pattern having a good cross-sectional shape and a small CD unevenness can be formed by wet etching. The present invention has been completed based on the findings and has the following constitution. (Configuration 1) A phase shift mask substrate which is used for manufacturing a phase shift mask for manufacturing a display device having a phase shift film pattern on a transparent substrate, and having a transparent substrate and formed thereon a phase shift film on a transparent substrate, the phase shift film having at least a lower layer having a function of adjusting a reflectance of light incident from the transparent substrate side; and an upper layer disposed on an upper side of the lower layer and having an adjustment The function of transmittance and phase difference of the exposed light; the phase shifting film has specific optical characteristics for the transmittance and phase difference of the exposed light, and the phase shifting film is 365 nm to 436 nm incident from the transparent substrate side. The reflectance of the light in the wavelength region is more than 20%, and the fluctuation range of the reflectance of the light in the wavelength region of 365 nm to 436 nm incident from the transparent substrate side is 10% or less. (Configuration 2) The phase shift mask substrate of the first aspect, wherein the phase shift film has a transmittance of 1% or more and 50% or less with respect to light having a wavelength of 365 nm included in the exposed light, and a phase difference It is 160° or more and 200° or less. (Configuration 3) The phase shift mask substrate according to the first or second aspect, wherein the upper layer is made of a material containing one or both of metal, oxygen, and nitrogen, and the lower layer is made of a material containing metal. The upper layer and the lower layer are made of a material that can be etched using the same etching liquid when patterning the phase shift film, and a ratio of an etching rate of the lower layer to an etching rate of the upper layer is more than 1 and 10 or less. (Configuration 4) The phase shift mask substrate of the third aspect is characterized in that the etching rate of the etching liquid to the phase shift film is 0.06 nm/sec or more and 2.5 nm/sec or less. (Claim 5) The phase shift mask substrate according to any one of 1 to 4, wherein the material constituting the upper layer is selected from the group consisting of a material containing metal and oxygen, a material containing metal and nitrogen, and a metal, oxygen. And a material of nitrogen, a material containing metal, cerium, and oxygen, a material containing metal, cerium, and nitrogen, and a material containing metal, cerium, oxygen, and nitrogen, and adding a pattern of the phase shifting film to the material The material used in the etching liquid used for the above-mentioned upper layer is a component having a faster etching rate or a slower component. (Claim 6) The phase shift mask substrate according to any one of 1 to 4, wherein the material constituting the lower layer is selected from the group consisting of a material containing metal, a material containing metal and tantalum, and the like. A material which is a component which slows the etching rate of the lower layer by the etching liquid used for patterning the phase shift film, or a component which becomes slow is added. (Structure 7) The phase shift mask substrate according to any one of 3 to 6, wherein the metal contained in the material constituting the upper layer and the metal contained in the material constituting the lower layer are each selected from titanium At least one of zirconium, molybdenum and niobium. (Structure 8) The phase shift mask substrate according to any one of 3 to 7, wherein the metal contained in the material constituting the upper layer is at least one selected from the group consisting of titanium and zirconium. (Configuration 9) The phase shift mask substrate of the sixth aspect is characterized in that the metal contained in the material constituting the lower layer is molybdenum, and the component for slowing the etching rate of the lower layer is carbon. (Structure 10) The phase shift mask substrate according to any one of 1 to 9, wherein the transparent substrate is made of SiO ₂ -TiO ₂ -based glass. (Structure 11) The phase shift mask substrate according to any one of 1 to 10, comprising: a light shielding film formed on the phase shift film. (Configuration 12) A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and is characterized by comprising: a resist pattern forming step, as in any of the configurations 1 to 10 Forming a resist pattern on the phase shift film of the phase shift mask base; and forming a phase shift film pattern by using the resist pattern as a mask, and performing wet etching on the phase shift film to form a phase Displacement film pattern. (Configuration 13) A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and characterized by: a resist pattern forming step of phase shifting light as in composition 11. a resist pattern is formed on the light shielding film of the cover base; a light shielding film pattern forming step of wet etching the light shielding film to form a light shielding film pattern; and a phase shift film pattern forming step In the step of using the light shielding film pattern as a mask, the phase shift film is wet-etched to form a phase shift film pattern. (Configuration 14) A pattern transfer method characterized in that a phase shift mask obtained by a method of manufacturing a phase shift mask of 12 or 13 is irradiated with light for exposure, and the pattern is transferred to a display. On the device substrate. (Configuration 15) The pattern transfer method according to the configuration 14, wherein the exposed light is a composite light including light of a plurality of wavelengths selected from a wavelength region of 365 nm to 436 nm. [Effects of the Invention] As described above, in the phase shift mask substrate of the present invention, the phase shift film has a reflectance (back reflectance) exceeding the wavelength range of 365 nm or more and 436 nm or less incident from the transparent substrate side. By 20%, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film pattern can be suppressed by reducing the absorption of the light on the phase shift film. Further, in addition to the optical characteristics of the back surface reflectance of the phase shift film, the phase shift film has a variation of 10% of the reflectance (back surface reflectance) of light in a wavelength region of 365 nm to 436 nm incident from the transparent substrate side. Hereinafter, when the light to be exposed is a composite light including light of a plurality of wavelengths selected from a wavelength region of 365 nm to 436 nm, the absorption of the light on the phase shift film can be further reduced, thereby suppressing The positional change of the phase shift film pattern caused by thermal expansion of the phase shift film pattern. Further, in the phase shift mask substrate of the present invention, the upper layer and the lower layer are formed of a material which can be etched using the same etching liquid when patterning the phase shift film, and the ratio of the etching speed of the lower layer to the etching speed of the upper layer When it exceeds 1 and is 10 or less, a phase shift film pattern which has a good cross-sectional shape and a small CD unevenness can be formed by wet etching. Therefore, it is possible to obtain a phase shift mask substrate in which a phase shift mask capable of accurately transferring a high-definition phase shift film pattern can be obtained. Further, the method of manufacturing a phase shift mask of the present invention is characterized in that the phase shift mask substrate of the present invention described above is used. Therefore, a phase shift film pattern having a small change in position can be formed. Further, a phase shift film pattern having a good cross-sectional shape and a small CD unevenness can be formed. Therefore, it is possible to manufacture a phase shift mask capable of accurately transferring a high-definition phase shift film pattern.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the following embodiment is an embodiment of the present invention, and the present invention is not limited to the scope. In the drawings, the same or equivalent components are denoted by the same reference numerals, and the description thereof is simplified or omitted. Embodiment 1. In Embodiment 1, a phase shift mask base will be described. Fig. 1 is a schematic view showing the film constitution of the 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 a light shielding film 40 formed on the phase shift film 30. The transparent substrate 20 is transparent to the exposed light. When the surface reflection loss is not caused, the transparent substrate 20 has a transmittance of 85% or more with respect to the light to be exposed, and preferably has a transmittance of 90% or more. The transparent substrate 20 is made of a material containing barium and oxygen, and can be made of synthetic quartz glass, quartz glass, aluminosilicate glass, soda lime glass, and low thermal expansion glass (SiO). ₂ -TiO ₂ Glass, etc.) is composed of a glass material. When the transparent substrate 20 is composed of a low thermal expansion glass, the positional change of the phase shift film pattern caused by the thermal deformation of the transparent substrate 20 can be suppressed. The phase shift film 30 has a lower layer 31 having a function of adjusting a reflectance of light incident on the side from the transparent substrate 20 (hereinafter sometimes referred to as a back surface reflectance), and an upper layer 32 disposed on the upper side of the lower layer 31, and It has the function of adjusting the transmittance and phase difference of the exposed light. The back reflectance of the phase shift film 30 is mainly affected by the lower layer 31, and the phase difference and transmittance of the phase shift film 30 are mainly affected by the upper layer 32. The lower layer 31 and the upper layer 32 can be formed by sputtering. The transmittance of the phase shift film 30 is 1% or more, preferably 3% or more, for the light having a wavelength of 365 nm included in the exposed light. Further, the transmittance of the phase shift film 30 is 70% or less, preferably 50% or less, and more preferably 40% or less with respect to the light having a wavelength of 365 nm included in the exposed light. As described above, the transmittance of the phase shift film 30 is 1% or more and 70% or less, preferably 1% or more and 50% or less, more preferably 3% or more, of the light having a wavelength of 365 nm included in the light to be exposed. 40% or less. The transmittance can be measured using a phase shift amount measuring device or the like. The phase difference of the phase shift film 30 is 160 or more, preferably 170 or more, for the light having a wavelength of 365 nm included in the exposed light. Further, the phase difference of the phase shift film 30 is 200 or less, more preferably 190 or less, for the light having a wavelength of 365 nm included in the light to be exposed. The phase difference can be measured using a phase shift amount measuring device or the like. The back surface reflectance of the phase shift film 30 is more than 20%, preferably 25% or more, more preferably 30% or more for light in the wavelength region of 365 nm to 436 nm. Further, the back surface reflectance of the phase shift film 30 is preferably 60% or less, more preferably 55% or less, for light in the wavelength region of 365 nm to 436 nm. When the back reflectance exceeds 20%, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film can be suppressed. From the above, the back surface reflectance of the phase shift film 30 is preferably 25% or more and 60% or less, more preferably 30% or more and 55% or less. Further, the fluctuation range of the back surface reflectance of the phase shift film 30 is 10% or less, preferably 7% or less, and more preferably 5% or less in the wavelength region of 365 nm to 436 nm. The back reflectance can be measured using a spectrophotometer or the like. Further, the variation range of the back reflectance is the difference between the maximum value and the minimum value of the back surface reflectance in the wavelength region of 365 nm to 436 nm. The upper layer 32 is made of a material containing one or both of metal, oxygen, and nitrogen in order to make the phase shift film 30 have a variation range of the back surface reflectance and the back surface reflectance described above, and to have the above-described phase difference and transmittance. The lower layer 31 is made of a material containing metal. Specific examples of the material constituting the upper layer 32 include a material containing metal and oxygen, a material containing metal and nitrogen, a material containing metal, oxygen and nitrogen, a material containing metal, cerium and oxygen, and a metal containing cerium. And nitrogen materials, as well as materials containing metals, bismuth, oxygen and nitrogen. Metal, ruthenium, oxygen and nitrogen are the main components of the material constituting the upper layer 32. Further, a material obtained by adding a component which causes an etching rate of the etching liquid used for patterning the phase shift film 30 to the upper layer 32 or a component which becomes slow is added to the materials. As the metal which is a main component of the material constituting the upper layer 32, a transition metal is preferable. Examples of the transition metal which is a main component of the material constituting the upper layer 32 include molybdenum (Mo), titanium (Ti), and zirconium (Zr). When the transition metal which is the main component contained in the material constituting the upper layer 32 is titanium (Ti), zirconium (Zr), and molybdenum (Mo), it is easy to adjust the phase difference and the transmittance to be required as the phase shift film 30. value. Further, when the transition metal which is the main component contained in the material constituting the upper layer 32 is titanium (Ti) and zirconium (Zr), the etching rate of the upper layer 32 of the etching liquid used when patterning the phase shift film 30 becomes Faster, the etching time of the phase shift film 30 can be shortened. The material constituting the upper layer 32 may contain two or more kinds of metals which are main components. When the material constituting the upper layer 32 includes a component which accelerates the etching rate, the content ratio of the component which increases the etching rate of the upper layer 32 is smaller than the content ratio of each of the principal components included in the material constituting the upper layer 32. Specific examples of the component for increasing the etching rate of the upper layer 32 include aluminum (Al). When the material constituting the upper layer 32 includes a component that slows the etching rate, the content ratio of the component that slows the etching rate of the upper layer 32 is smaller than the content ratio of each of the principal components included in the material constituting the upper layer 32. Specific examples of the component for slowing the etching rate of the upper layer 32 include carbon (C) and tantalum (Ta). Furthermore, it is within the scope of the invention to include other elements within the scope of the characteristics of the upper layer 32. More specifically, as a material constituting the lower layer 31, a material containing a metal and a material containing a metal and a crucible may be mentioned. The metal and tantalum are the main components of the material constituting the lower layer 31. Further, a material in which a component which slows the etching rate of the lower layer 31 by the etching liquid used for patterning the phase shift film 30 or a component which is fastened is added to the materials. As the metal which is a main component of the material constituting the lower layer 31, a transition metal is preferable. Examples of the transition metal which is a main component of the material constituting the lower layer 31 include molybdenum (Mo), titanium (Ti), and zirconium (Zr). When the transition metal which is the main component contained in the material constituting the upper layer 32 is titanium (Ti), zirconium (Zr) or molybdenum (Mo), it becomes a transition metal which is a main component contained in the material constituting the lower layer 31. Also preferred are titanium (Ti), zirconium (Zr) and molybdenum (Mo). When the transition metal which is the main component contained in the material constituting the lower layer 31 is titanium (Ti), zirconium (Zr), and molybdenum (Mo), when the phase shift film 30 is patterned, it is easy to use the same etching liquid pair. The upper layer 32 and the lower layer 31 are etched. The material constituting the lower layer 31 may contain two or more kinds of metals which are main components. When the material constituting the lower layer 31 includes a component that slows down the etching rate, the content ratio of the component that slows down the etching rate of the lower layer 31 is smaller than the content ratio of each of the principal components included in the material constituting the lower layer 31. Specific examples of the component for slowing the etching rate of the lower layer 31 include carbon (C), bismuth (Si), and tantalum (Ta). When the material constituting the lower layer 31 includes a component which accelerates the etching rate, the content ratio of the component which causes the etching rate of the lower layer 31 to be faster is smaller than the content ratio of each of the main components included in the material constituting the lower layer 31. Specific examples of the component for increasing the etching rate of the lower layer 31 include aluminum (Al). Furthermore, it is within the scope of the invention to include other elements within a range that does not affect the characteristics of the lower layer 31. When the lower layer 31 contains one or both of oxygen and nitrogen, the total content of oxygen and nitrogen in the lower layer 31 is preferably smaller than the total content of oxygen and nitrogen in the upper layer 32. When the content of oxygen and nitrogen contained in the lower layer 31 is small, the sheet resistance of the phase shift film is lowered, so that electrostatic breakdown of the phase shift film pattern formed in the phase shift mask can be prevented. The total content of oxygen and nitrogen can be measured by using an Oujie electron spectroscopy apparatus or an X-ray photoelectron spectroscopy (XPS (X-ray photoelectron spectroscopy)). The upper layer 32 and the lower layer 31 are made of a material which can be etched using the same etching liquid when the phase shift film 30 is patterned. Further, when the upper layer 32 and the lower layer 31 are etched using the same etching liquid, the ratio of the etching rate of the lower layer 31 to the etching rate of the upper layer 32 exceeds 1 and is 10 or less. When the ratio of the etching rates exceeds 1 and is 10 or less, the phase shift film pattern after the wet etching has a good cross-sectional shape and a small CD unevenness. The comparison between the etching rate of the lower layer 31 and the etching rate of the upper layer 32 is preferably more than 1 and 5 or less, more preferably more than 1 and 3 or less. The ratio of the etching rate of the lower layer 31 to the etching speed of the upper layer 32 in the embodiment is obtained by forming the upper layer 32 and the lower layer 31 on the transparent substrate 20 under the respective film formation conditions. For each sample obtained, the etching rate of the sample of the lower layer 31 is divided by the etching rate of the sample of the upper layer 32, after calculating the respective etching rates based on the etching time and film thickness of the sample of the upper layer 32 and the sample of the lower layer 31. As a method of calculating the ratio of the etching rate other than the above, there is a method of measuring the reflectance of the film of the upper layer 32 and the lower layer 31 during etching and detecting the etching end point of the upper layer 32 and the lower layer 31, and according to the film thickness of each layer. After the etching rate of the upper layer 32 and the lower layer 31 is calculated by the etching end time, the etching rate of the lower layer 31 is divided by the etching rate of the upper layer 32. The etching rate of the etching liquid for etching the upper layer 32 and the lower layer 31 to the phase shift film 30 is preferably 0.06 nm/sec or more, more preferably 0.2 nm/sec or more. Further, the etching rate of the etching liquid for etching the upper layer 32 and the lower layer 31 to the phase shift film 30 is preferably 2.5 nm/sec or less, more preferably 2.0 nm/sec or less. As the etching liquid for etching the upper layer 32 and the lower layer 31 when the phase shift film 30 is patterned, an etchant containing a fluorine compound such as ammonium hydrogen fluoride or ammonium fluoride, and an oxidizing agent such as phosphoric acid, nitric acid, sulfuric acid or hydrogen peroxide can be used. . For example, an etching solution containing ammonium hydrogen fluoride and hydrogen chloride, and an etching liquid containing ammonium fluoride, phosphoric acid, and hydrogen peroxide can be mentioned. Examples of the material constituting the upper layer 32 include MoSiN, MoSiON, MoSiO, ZrSiN, ZrSiON, ZrSiO, TiO, TiON, TiSiO, and TiSiON. Further, those in which C or Ta is added as a component for slowing the etching rate and Al is added as a component for increasing the etching rate are mentioned. Examples of the material constituting the lower layer 31 include Mo, MoSi, Ta, TaSi, Zr, ZrSi, Ti, TiSi, and the like. Further, those in which C or Ta is added as a component for slowing the etching rate and Al is added as a component for increasing the etching rate are mentioned. As a preferable combination of the upper layer 32 and the lower layer 31, for example, a combination in which the upper layer 32 is MoSiN and the lower layer 31 is MoSiC (Example 1), the upper layer 32 is ZrSiN, and the lower layer 31 is MoSi (Example 2), the upper layer 32 TiO ₂ Further, the lower layer 31 is a combination of MoSi (Example 3) and the upper layer 32 is ZrSiON and the lower layer 31 is a combination of ZrSi (Example 4). The thickness of the upper layer 32 and the lower layer 31 is adjusted so that the phase shift film 30 becomes the fluctuation range of the back surface reflectance and the back surface reflectance described above, and becomes the phase difference and the transmittance described above. From the viewpoint of the cross-sectional shape of the phase shift film pattern, it is preferred to be as thin as possible. The thickness of the upper layer 32 is preferably 180 nm or less, more preferably 160 nm or less. In addition, the thickness of the lower layer 31 is preferably 3 nm or more, and more preferably 5 nm or more from the viewpoint of the fluctuation range of the back surface reflectance and the back surface reflectance and the thickness uniformity in the substrate surface. From the viewpoint of the cross-sectional shape of the phase shift film pattern, the thickness of the lower layer 31 is preferably as thin as possible. Specifically, the thickness of the lower layer 31 is preferably 50 nm or less, more preferably 30 nm or less. The lower layer 31 and the upper layer 32 may be in the form of a single film having a uniform composition, or may be in the case of a plurality of films having different compositions, or may be in the form of a single film which is continuously changed in the thickness direction. The light shielding film 40 is made of a material that is chemically resistant to the etching liquid used when patterning the phase shift film 30. A material suitable as the light shielding film 40 is a chromium-based material. More specifically, the chromium-based material may be chromium (Cr) or a material containing at least one of chromium (Cr), carbon (C), nitrogen (N), oxygen (O), and fluorine (F). For example, examples of the material constituting the light shielding film 40 include Cr, CrC, CrN, CrO, CrCN, CrON, CrCO, and CrCON. The light shielding film 40 can be formed by a sputtering method. In the portion where the phase shift film 30 and the light shielding film 40 are laminated, the optical density of the light to be exposed is preferably 3 or more, and more preferably 4 or more. The optical density can be measured using a spectrophotometer or an OD (Optical Densitometer). The light-shielding film 40 may be a single film including a uniform composition, a case where a plurality of films having different compositions are included, or a case where a film consisting of a single film continuously changing in the thickness direction may be included. Further, the phase shift mask substrate 10 shown in FIG. 1 is provided with a light shielding film 40 on the phase shift film 30, but the phase shift mask substrate having no light shielding film 40 on the phase shift film 30 may be applied to the substrate. invention. Further, the present invention can also be applied to a phase shift mask substrate having a light shielding film 40 on the phase shift film 30 and a resist film on the light shielding film 40. Further, the present invention can also be applied to a phase shift mask substrate having a light-shielding film 40 on the phase shift film 30 and a resist film on the phase shift film 30. Next, a method of manufacturing the phase shift mask substrate 10 of the embodiment will be described. The phase shift mask substrate 10 shown in Fig. 1 is produced by performing the following phase shift film forming step and light shielding film forming step. Hereinafter, each step will be described in detail. 1. Phase Displacement Film Forming Step First, the transparent substrate 20 is prepared. The transparent substrate 20 may be made of synthetic quartz glass, quartz glass, aluminosilicate glass, soda lime glass, and low thermal expansion glass (SiO) as long as it is transparent to the exposed light. ₂ -TiO ₂ Glass, etc.). Next, the phase shift film 30 is formed on the transparent substrate 20 by sputtering. The phase shift film 30 is formed by forming the lower layer 31 on the main surface of the transparent substrate 20 and forming the upper layer 32 on the lower layer 31. The film formation of the lower layer 31 is performed by using a sputtering target containing a metal which is a main component of a material constituting the lower layer 31 or a sputtering target containing the metal and ruthenium, for example, in a sputtering gas atmosphere containing an inert gas, the inert gas It comprises at least one selected from the group consisting of helium, neon, argon, xenon, and xenon. When the material constituting the lower layer 31 contains carbon as a component that slows the etching rate of the lower layer 31, carbon dioxide gas, a hydrocarbon-based gas, or the like is further added to the sputtering gas atmosphere. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. When the material constituting the lower layer 31 contains a component which is a component which slows the etching rate of the lower layer 31, a sputtering target containing ruthenium is used. When the material constituting the lower layer 31 contains aluminum as a component which accelerates the etching rate of the lower layer 31, a sputtering target containing aluminum is used. Similarly, the film formation of the upper layer 32 is performed by using a sputtering target containing a metal and a crucible which are main components of the material constituting the upper layer 32, for example, in a sputtering gas atmosphere containing a mixed gas of an inert gas and an active gas, which is inert. The gas comprises at least one selected from the group consisting of helium, neon, argon, helium and neon, the active gas comprising a group selected from the group consisting of oxygen, nitrogen, nitric oxide gas and nitrogen dioxide. At least one of them. When the material constituting the upper layer 32 contains aluminum as a component which accelerates the etching speed of the upper layer 32, a sputtering target containing aluminum is used. When the material constituting the upper layer 32 contains carbon which is a component which slows the etching rate of the upper layer 32, carbon dioxide gas, a hydrocarbon-based gas or the like is further added to the sputtering gas atmosphere. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. When the material constituting the upper layer 32 contains ruthenium which is a component which slows the etching rate of the upper layer 32, a sputtering target containing ruthenium is used. When the lower layer 31 and the upper layer 32 are formed, the composition and thickness of each of the lower layer 31 and the upper layer 32 are such that the phase shift film 30 has a variation range of the back surface reflectance and the back surface reflectance described above, and the phase difference and the transmission are the above. The rate is adjusted. The composition of each of the lower layer 31 and the upper layer 32 can be controlled by the composition of the sputtering gas, the flow rate, and the like. The thickness of each of the lower layer 31 and the upper layer 32 can be controlled by sputtering power, sputtering time, and the like. Further, in the case where the sputtering apparatus is a continuous sputtering apparatus, the thickness of each of the lower layer 31 and the upper layer 32 can be controlled by the substrate transfer speed. When the lower layer 31 includes a single film having a uniform composition, the film formation process is performed only once without changing the composition and flow rate of the sputtering gas. In the case where the lower layer 31 includes a plurality of films having different compositions, the film forming process is performed plural times for changing the composition and flow rate of the sputtering gas for each film forming process. When the lower layer 31 includes a single film which is continuously changed in the thickness direction, the film formation process is performed only once, while changing the composition and flow rate of the sputtering gas. The film formation of the upper layer 32 is also the same. In the case where a plurality of film forming processes are performed, the sputtering power applied to the sputtering target can be made small. 2. Light-Shielding Film Forming Step After the phase-shift film 30 is formed, the light-shielding film 40 is formed on the phase shift film 30 by sputtering. In this way, the phase shift mask substrate 10 is obtained. The film formation of the light shielding film 40 uses a sputtering target containing a chromium or chromium compound, for example, sputtering containing at least one inert gas selected from the group consisting of helium, neon, argon, neon, and xenon. Performing in a gas atmosphere or in a sputtering gas atmosphere containing a mixed gas of an inert gas and a reactive gas, the inert gas comprising at least one selected from the group consisting of helium, neon, argon, neon, and xenon. In one aspect, the active gas comprises at least one selected from the group consisting of oxygen, nitrogen, nitrogen monoxide, nitrogen dioxide, carbon dioxide gas, hydrocarbon gas, and fluorine gas. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. In the case where the light-shielding film 40 includes a single film having a uniform composition, the film formation process is performed only once without changing the composition and flow rate of the sputtering gas. When the light shielding film 40 includes a plurality of films having different compositions, the film forming process is performed plural times for changing the composition and flow rate of the sputtering gas for each film forming process. In the case where the light-shielding film 40 includes a single film which continuously changes in the thickness direction, the film formation process is performed only once, while changing the composition and flow rate of the sputtering gas. The lower layer 31, the upper layer 32, and the light shielding film 40 are preferably continuously formed using a continuous sputtering apparatus, and are not exposed to the atmosphere by taking the transparent substrate 20 out of the apparatus. The surface oxidation or surface carbonization of the undesired layers can be prevented by continuously forming a film without taking it out of the apparatus. The undesired surface oxidation or surface carbonization of each layer is such that when the laser light used for drawing the resist film formed on the light shielding film 40 or the phase shift film pattern is transferred to the resist film formed on the substrate of the display device The reflectance of the exposed light used is varied, and the etch rate of the oxidized portion or the carbonized portion is changed. Further, the phase shift mask substrate 10 shown in FIG. 1 is provided with the light shielding film 40 on the phase shift film 30. Therefore, when the phase shift mask substrate 10 is manufactured, a light shielding film forming step is performed to fabricate the phase shift film 30. When the phase shift mask substrate of the light shielding film 40 is not provided, the light shielding film forming step is not performed. Further, when a phase shift mask substrate including the light shielding film 40 on the phase shift film 30 and a resist film on the light shielding film 40 is produced, a resist film is formed on the light shielding film 40 after the light shielding film forming step. Further, when the phase shift film 30 is not provided with the light shielding film 40 and the phase shift film 30 is provided with the phase shift mask substrate of the resist film, the light shielding film forming step is not performed, and after the phase shift film forming step, A resist film is formed on the phase shift film 30. In the phase shift mask substrate 10 of the first embodiment, the reflectance (back surface reflectance) of the phase shift film 30 in the wavelength range of 365 nm or more and 436 nm or less incident from the side of the transparent substrate 20 exceeds 20%. By reducing the absorption of the light by the exposure of the phase shift film 30, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film pattern can be suppressed. Further, in the phase shift mask substrate 10 of the first embodiment, the reflectance (back surface reflectance) of the phase shift film 30 with respect to light in the wavelength region of 365 nm to 436 nm incident from the side of the transparent substrate 20 is 10 When the light to be exposed is a composite light containing light of a plurality of wavelengths selected from a wavelength region of 365 nm to 436 nm, the absorption of the light by the phase shift film 30 can be further suppressed. The positional change of the phase shift film pattern caused by thermal expansion of the phase shift film pattern. Further, in the phase shift mask substrate 10 of the first embodiment, the upper layer 32 and the lower layer 31 are made of a material which can be etched using the same etching liquid when patterning the phase shift film 30, and the etching speed of the lower layer 31 is higher than that of the upper layer 32. Since the ratio of the etching speed exceeds 1 and is 10 or less, a phase shift film pattern having a good cross-sectional shape and a small CD unevenness can be formed by wet etching. Therefore, it is possible to obtain a phase shift mask substrate in which a phase shift mask capable of accurately transferring a high-definition phase shift film pattern can be obtained. Embodiment 2. In Embodiment 2, a method of 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 substrate using the phase shift mask substrate 10 shown in FIG. 1, and includes the following first resist pattern forming step and first light shielding film. The pattern forming step, the phase shift film pattern forming step, the second resist pattern forming step, and the second light shielding film pattern forming step. Hereinafter, each step will be described in detail. 1. First resist pattern forming step In the first resist pattern forming step, first, a resist film is formed on the light shielding film 40 of the phase shift mask substrate 10 of the first embodiment. The resist film material to be used is not particularly limited. It suffices to be a laser light having a wavelength selected from any wavelength range of 350 nm to 436 nm, which will be described later. Further, the resist film may be either a positive type or a negative type. Thereafter, laser light having any one of wavelengths selected from the wavelength range of 350 nm to 436 nm is used to draw a specific pattern on the resist film. The pattern drawn on the resist film is formed in the pattern of the phase shift film. Thereafter, the resist film is developed by using a specific developer, and the first resist pattern 50 is formed on the light shielding film 40. 2. First Light-Shielding Film Pattern Forming Step In the first light-shielding film pattern forming step, first, the light-shielding film 40 is etched using the first resist pattern 50 as a mask to form a first light-shielding film pattern 40a. The light shielding film 40 is formed of, for example, a chromium-based material containing chromium (Cr). The etching liquid for etching the light shielding film 40 is not particularly limited as long as it can selectively etch the light shielding film 40. Specifically, an etching solution containing cerium ammonium nitrate and perchloric acid is mentioned. Thereafter, the first resist pattern 50 is peeled off by using a resist stripping liquid or by ashing. 3. Phase Displacement Film Pattern Forming Step In the first phase shift film pattern forming step, the phase shift film 30 is etched using the first light-shielding film pattern 40a as a mask to form a phase shift film including the upper layer pattern 32a and the lower layer pattern 31a. Pattern 30a. The upper layer 32 and the lower layer 31 included in the phase shift film 30 include a material which can be etched using the same etching liquid. Therefore, the upper layer 32 and the lower layer 31 can be etched by the same etching solution. The etching liquid for etching the phase shift film 30 is not particularly limited as long as it can selectively etch the phase shift film 30. For example, an etching solution containing ammonium fluoride, phosphoric acid, and hydrogen peroxide, and an etching solution containing ammonium hydrogen fluoride and hydrogen chloride can be mentioned. 4. Second resist pattern forming step In the second resist pattern forming step, first, a resist film covering the first light-shielding film pattern 40a is formed. The resist film material to be used is not particularly limited. It suffices to be sensitive to laser light having any of wavelengths selected from the wavelength range of 350 nm to 436 nm described later. Further, the resist film may be either a positive type or a negative type. Thereafter, laser light having any one of wavelengths selected from the wavelength range of 350 nm to 436 nm is used to draw a specific pattern on the resist film. The pattern drawn on the resist film is a light-shielding strip pattern that is shielded from the peripheral region of the region where the phase shift film is patterned. Thereafter, the resist film is developed by a specific developer, and the second resist pattern 60 is formed on the first light-shielding film pattern 40a. 5. Second Light-Shielding Film Pattern Forming Step In the second light-shielding film pattern forming step, the first light-shielding film pattern 40a is etched using the second resist pattern 60 as a mask to form the second light-shielding film pattern 40b. The first light-shielding film pattern 40a is formed of a chromium-based material containing chromium (Cr). The etching liquid for etching the first light-shielding film pattern 40a is not particularly limited as long as it can selectively etch the first light-shielding film pattern 40a. For example, an etching solution containing cerium ammonium nitrate and perchloric acid can be mentioned. Thereafter, the second resist pattern 60 is peeled off by using a resist stripping solution or by ashing. In this way, the phase shift mask 100 is obtained. Further, the phase shift mask substrate 10 shown in FIG. 1 is provided with the light shielding film 40 on the phase shift film 30. Therefore, when the phase shift mask is manufactured using the phase shift mask substrate 10 shown in FIG. 1, the first step is performed. The resist pattern forming step, the first light shielding film pattern forming step, the phase shift film pattern forming step, the second resist pattern forming step, and the second light shielding film pattern forming step, but the light shielding film 40 is not provided on the phase shift film 30. When the phase shift mask substrate is used to manufacture the phase shift mask, a resist pattern forming step and a phase shift film pattern forming step are performed. Here, in the resist pattern forming step, a resist pattern is formed on the phase shift film 30, and in the phase shift film pattern forming step, the resist pattern is used as a mask to form a phase shift film pattern. Further, when the phase shift film 40 is provided with the phase shift film 30 and the phase shift mask is provided on the light-shielding film 40 having the resist film, the first resist pattern forming step is not required to be applied to the light-shielding film 40. A process of forming a resist film thereon. Further, when the phase shift film 30 is not provided with the light shielding film 40, and the phase shift film 30 is provided with the resist film phase shift mask substrate, the phase shift mask is not required to be used for the phase shift film by the resist pattern forming step. A process of forming a resist film on 30. According to the method of manufacturing a phase shift mask of the second embodiment, since the phase shift mask substrate of the first embodiment is used, a phase shift film pattern having a small change in position can be formed. Further, a phase shift film pattern having a good cross-sectional shape and a small CD unevenness can be formed. Therefore, it is possible to manufacture a phase shift mask which can accurately transfer a high-definition phase shift film pattern. Embodiment 3. In Embodiment 3, a method of manufacturing a display device will be described. The display device is manufactured by performing the following photomask mounting step and pattern transfer step. The pattern transfer step corresponds to a pattern transfer method. Hereinafter, each step will be described in detail. 1. Mounting Step In the placing step, the phase shift mask manufactured in the second embodiment is placed on the mask stage of the exposure apparatus. Here, the phase shift mask is disposed to face the resist film formed on the substrate of the display device with a projection optical system that is exposed to the exposure device. For example, a projection exposure apparatus having an equal magnification projection optical system is used as the exposure apparatus. 2. Pattern Transfer Step In the pattern transfer step, the phase shift mask is irradiated with the exposed light, and the phase shift film pattern is transferred to the resist film formed on the substrate of the display device. The exposed light is a composite light comprising light of a plurality of wavelengths selected from a wavelength region of 313 nm to 436 nm. For example, the light to be exposed includes composite light of i-rays, h-rays, and g-rays, or composite light including j-rays, i-rays, h-rays, and g-rays. When composite light is used as the light for exposure, the light intensity of the exposure can be increased to increase the throughput, so that the manufacturing cost of the display device can be reduced. According to the method of manufacturing the display device of the third embodiment, since the phase shift mask manufactured in the second embodiment is used, the resolution of the transfer pattern transferred onto the display device substrate is improved, and the pattern line width can be made 1.8 μm. The following line and gap pattern or hole pattern are high-resolution, high-definition display devices that are transferred without causing CD errors. [Examples] Hereinafter, the present invention will be more specifically described based on examples and comparative examples. Further, the following examples are merely examples of the invention and are not intended to limit the invention. The phase shift mask substrates of Examples 1 to 6 and Comparative Example 1 were provided with a transparent substrate, a phase shift film formed on the transparent substrate, and a light shielding film formed on the phase shift film. As the transparent substrate, a synthetic quartz glass substrate having a size of 800 mm × 920 mm and a thickness of 10 mm was used. Hereinafter, Examples 1 to 6 and Comparative Example 1 will be described in detail. Example 1. The phase shift film of the phase shift mask substrate of Example 1 comprises a lower layer (MoSi, film thickness 10 nm) and an upper layer (MoSiN, film thickness 155 nm) arranged in sequence from the transparent substrate side. With the above two-layer structure, the phase shift film has a transmittance of 3.5% for light at 365 nm and a phase difference of 179.7°. Further, the transmittance and the phase difference were measured using MPM-100 (trade name) manufactured by Lasertec. The measurements were also carried out in the same manner in Examples 2 to 6 and Comparative Example 1. The back reflectance of the phase shift film is 43.0% for the wavelength 365 nm, 42.2% for the wavelength 405 nm, and 42.4% for the wavelength 436 nm. Further, the reflectance of the back surface of the phase shift film in the wavelength region of 365 nm to 436 nm fluctuated by 0.8%. Therefore, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film can be suppressed. In addition, the back surface reflectance was measured using SolidSpec-3700 (trade name) manufactured by Shimadzu Corporation. The measurements were also carried out in the same manner in Examples 2 to 6 and Comparative Example 1. Moreover, the range of fluctuation of the back surface reflectance is calculated based on the measurement result of the back surface reflectance. The same was calculated in the examples 2 to 6. In the case of using an etching solution containing ammonium hydrogen fluoride and hydrogen chloride, the ratio of the etching rate of the lower layer to the etching rate of the upper layer was 1.7. Therefore, the cross-sectional shape of the phase shift film pattern after the wet etching is good, and the CD unevenness becomes small. Further, the etching rate of the etching solution containing ammonium hydrogen fluoride and hydrogen chloride to the phase shift film was 0.07 nm/sec. The phase shift mask substrate of Example 1 was produced by the following method. First, a synthetic quartz glass substrate as a transparent substrate is prepared. The two major surfaces of the transparent substrate are mirror ground. The two main surfaces of the transparent substrates prepared in Examples 2 to 6 and Comparative Example 1 were similarly mirror-polished. Thereafter, the transparent substrate is carried into the continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. A MoSi target and a Cr target are disposed in the sputtering chamber. Thereafter, a sputtering power of 5.0 kW was applied to the MoSi target (Mo: Si = 1:4) disposed in the sputtering chamber, and Ar gas was introduced into the sputtering chamber at a flow rate of 100 sccm. When the transparent substrate passes near the MoSi target, a layer containing MoSi having a thickness of 10 nm is formed on the main surface of the transparent substrate. Thereafter, a sputtering power of 7.0 kW was applied to the MoSi target disposed in the sputtering chamber, and Ar gas and N were applied. ₂ The gas mixture gas becomes 100 sccm and N in Ar gas ₂ The gas was introduced into the sputtering chamber as the gas flow rate was 60 sccm, and the transparent substrate was transferred. When the transparent substrate passes through the vicinity of the MoSi target, a film having a film thickness of 155 nm containing MoSiN is formed on the lower layer. Thereafter, a sputtering power of 8.6 kW was applied to the Cr target, and Ar gas and CO were applied on one side. ₂ The gas mixture gas becomes 100 sccm and CO in Ar gas ₂ The gas was introduced into the sputtering chamber as the gas flow rate was 20 sccm, and the transparent substrate was transferred. Thereafter, a phase shift film including a lower layer (MoSi, film thickness: 10 nm) and an upper layer (MoSiN, film thickness: 155 nm), and a transparent substrate of a light-shielding film (CrOC, film thickness: 130 nm) are formed by continuous sputtering. The device is taken out and washed. Further, the film formation of the lower layer, the film formation of the upper layer, and the film formation of the light-shielding film are continuously performed in the continuous sputtering apparatus, and the transparent substrate is not exposed to the atmosphere by being taken out of the continuous sputtering apparatus. in. Using the phase shift mask substrate described above, a phase shift mask was fabricated by the following method. First, a resist film containing a positive-type photoresist of a novolak type is formed on the light-shielding film of the phase shift mask base. Thereafter, a laser beam having a wavelength of 413 nm was used by a laser drawing machine to draw a line and gap pattern of 1.8 μm on the resist film. Thereafter, the resist film is developed by a specific developer to form a first resist pattern on the light shielding film. Thereafter, the light-shielding film is etched using the first resist pattern as a mask to form a first light-shielding film pattern. As the etching liquid for etching the light shielding film, an etching liquid containing cerium ammonium nitrate and perchloric acid is used. Thereafter, the first resist pattern is peeled off using a resist stripper. Thereafter, the phase shift film is etched using the first light-shielding film pattern as a mask to form a phase shift film pattern. As the etching liquid for etching the phase shift film, an etching solution containing ammonium hydrogen fluoride and hydrogen chloride is used. Thereafter, a resist film covering the first light-shielding film pattern and containing a positive-type photoresist of a novolak type is formed. Thereafter, a laser beam having a wavelength of 413 nm was used by a laser drawing machine to draw a specific pattern on the resist film. Thereafter, the resist film is developed by a specific developer, and a second resist pattern is formed on the first light-shielding film pattern. Thereafter, the first light-shielding film pattern is etched using the second resist pattern as a mask to form a second light-shielding film pattern. As the etching liquid for etching the first light-shielding film pattern, an etching liquid containing cerium ammonium nitrate and perchloric acid is used. The section of the phase shift film pattern of the phase shift mask manufactured by using the phase shift mask substrate described above is slightly eroded at the boundary between the layer and the lower layer in the film thickness direction of the phase shift film pattern, but does not affect the characteristics of the mask. degree. In addition, the phase shift film pattern profile of the phase shift mask was observed using an electron microscope (JSM7401F (trade name) manufactured by JEOL Ltd.). Observations were also made in the same manner in Examples 2 to 6 and Comparative Example 1. The CD of the phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above is not 50 nm, which is good. The CD unevenness is the offset width from the target line and gap pattern (width of the line pattern: 1.8 μm, width of the gap pattern: 1.8 μm). Further, the CD unevenness of the phase shift film pattern of the phase shift mask was measured using SIR8000 manufactured by Seiko Instruments Nano Technologies. The measurements were also carried out in the same manner in Examples 2 to 6 and Comparative Example 1. The phase shift film pattern of the phase shift mask has a small change in position, and the phase shift film pattern has an excellent pattern cross-sectional shape and excellent CD uniformity. Further, it has been confirmed that the phase shift mask has excellent optical characteristics (back surface reflectance, variation in back surface reflectance, transmittance, and phase difference), so that the positional shift during pattern transfer is also suppressed. And the resolution of the transfer pattern transferred onto the substrate of the display device is improved, and the line having a pattern line width of 1.8 μm and the gap pattern are transferred without causing CD errors. Further, the pattern transfer using the phase shift mask is performed by a projection exposure method using an equal magnification projection optical system. The exposed light includes a composite light of i-rays, h-rays, and g-rays. The same applies to Examples 2 to 6. Example 2. The phase shift film of the phase shift mask substrate of Example 2 comprises a lower layer (MoSi, film thickness 3 nm) and an upper layer (ZrSiN, film thickness 75 nm) arranged in sequence from the transparent substrate side. In the second embodiment, the etching speed of the lower layer of MoSi is faster, so that the upper layer contains Zr and the etching speed is made faster. With the above two-layer structure, the phase shift film has a transmittance of 3.1% for light at 365 nm and a phase difference of 177.4°. The back reflectance of the phase shifting film is 41.5% for the wavelength 365 nm, 41.2% for the wavelength 405 nm, and 38.3% for the wavelength 436 nm. Further, the reflectance of the back surface of the phase shift film in the wavelength region of 365 nm to 436 nm was changed by 3.2%. Therefore, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film can be suppressed. In the case of using an etching solution containing ammonium hydrogen fluoride and hydrogen chloride, the ratio of the etching rate of the lower layer to the etching rate of the upper layer was 1.9. Therefore, the cross-sectional shape of the phase shift film pattern after the wet etching is good, and the CD unevenness becomes small. Further, the etching rate of the etching solution containing ammonium hydrogen fluoride and hydrogen chloride to the phase shift film was 0.26 nm/sec. The phase shift mask substrate of Example 2 was produced by the same method as in Example 1 except for the film forming step of the phase shift film. The film formation step of the phase shift film of Example 2 is as follows. First, the transparent substrate is carried into a continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. In the sputtering chamber, a MoSi target (Mo: Si = 1:4), a ZrSi target (Zr: Si = 1:2), and a Cr target were disposed. Thereafter, a sputtering power of 3.0 kW was applied to the MoSi target placed in the sputtering chamber, and the Ar gas was introduced into the sputtering chamber at a flow rate of 55 sccm to transport the transparent substrate. When the transparent substrate passes near the MoSi target, a layer containing MoSi having a thickness of 3 nm is formed on the main surface of the transparent substrate. Thereafter, a sputtering power of 5.6 kW was applied to the ZrSi target disposed in the sputtering chamber, and Ar gas and N were applied. ₂ The gas mixture gas becomes 50 sccm and N in Ar gas ₂ The gas was introduced into the sputtering chamber as the gas flow rate was 40 sccm, and the transparent substrate was transferred. When the transparent substrate passes through the vicinity of the ZrSi target, a layer containing ZrSiN having a thickness of 75 nm is formed on the lower layer. A phase shift mask was produced by the same method as in Example 1 using the above phase shift mask substrate. The phase shift film pattern profile of the phase shift mask manufactured using the phase shift mask substrate is slightly eroded at the interface between the layer and the lower layer in the film thickness direction of the phase shift film pattern, but does not affect the characteristics of the mask. . The CD of the phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above is not 45 nm, which is good. The phase shift film pattern of the phase shift mask has a small change in position, and the phase shift film pattern has an excellent pattern cross-sectional shape and excellent CD uniformity. Further, it has been confirmed that the phase shift mask has excellent optical characteristics (back surface reflectance, variation in back surface reflectance, transmittance, and phase difference), so that the positional shift during pattern transfer is also suppressed. And the resolution of the transfer pattern transferred onto the substrate of the display device is improved, and the line having a pattern line width of 1.8 μm and the gap pattern are transferred without causing CD errors. Embodiment 3. The phase shifting film of the phase shift mask substrate of Embodiment 3 comprises a lower layer (MoSi, film thickness 10 nm) and an upper layer (TiO) arranged in sequence from the transparent substrate side. ₂ , film thickness 110 nm). In the third embodiment, the etching speed of the lower layer of MoSi is faster, so that the material of the upper layer contains Ti and the etching rate is increased. With the above two-layer structure, the phase shift film has a transmittance of 13.8% for light at 365 nm and a phase difference of 185.0°. The back reflectance of the phase shifting film is 47.6% for the wavelength 365 nm, 52.2% for the wavelength 405 nm, and 53.6% for the wavelength 436 nm. Further, the reflectance of the back surface of the phase shift film in the wavelength region of 365 nm to 436 nm fluctuated by 6.0%. Therefore, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film can be suppressed. In the case of using an etching solution containing ammonium hydrogen fluoride and hydrogen chloride, the ratio of the etching rate of the lower layer to the etching rate of the upper layer was 1.7. Therefore, the cross-sectional shape of the phase shift film pattern after the wet etching is good, and the CD unevenness becomes small. Further, the etching rate of the etching solution containing ammonium hydrogen fluoride and hydrogen chloride to the phase shift film was 0.15 nm/sec. The phase shift mask substrate of Example 3 was produced by the same method as in Example 1 except for the film forming step of the phase shift film. The film formation step of the phase shift film of Example 3 is as follows. First, the transparent substrate is carried into a continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. A MoSi target (Mo: Si = 1:4), a Ti target, and a Cr target were disposed in the sputtering chamber. Thereafter, a sputtering power of 5.5 kW was applied to the MoSi target placed in the sputtering chamber, and the Ar gas was introduced into the sputtering chamber at a flow rate of 75 sccm to transport the transparent substrate. When the transparent substrate passes through the vicinity of the MoSi target, a layer containing MoSi having a thickness of 3 nm is formed on the main surface of the transparent substrate. Thereafter, a sputtering power of 7.5 kW is applied to the Ti target disposed in the sputtering chamber, and Ar gas and O are applied. ₂ The mixed gas of gas becomes 45 sccm and O in Ar gas ₂ The gas was introduced into the sputtering chamber as the gas flow rate was 35 sccm, and the transparent substrate was transferred. When the transparent substrate passes near the Ti target, the film is formed on the lower layer to contain TiO. ₂ The film has a thickness of 200 nm above. A phase shift mask was produced by the same method as in Example 1 using the above phase shift mask substrate. The phase shift film pattern profile of the phase shift mask manufactured using the phase shift mask substrate is slightly eroded at the interface between the layer and the lower layer in the film thickness direction of the phase shift film pattern, but does not affect the characteristics of the mask. . The CD of the phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above was not 55 nm and was good. The phase shift film pattern of the phase shift mask has a small change in position, and the phase shift film pattern has an excellent pattern cross-sectional shape and excellent CD uniformity. Further, it has been confirmed that the phase shift mask has excellent optical characteristics (back surface reflectance, variation in back surface reflectance, transmittance, and phase difference), so that the positional shift during pattern transfer is also suppressed. And the resolution of the transfer pattern transferred onto the substrate of the display device is improved, and the line having a pattern line width of 1.8 μm and the gap pattern are transferred without causing CD errors. Example 4. The phase shift film of the phase shift mask substrate of Example 4 comprises a lower layer (ZrSi, film thickness 18 nm) and an upper layer (ZrSiON, film thickness 17 nm) arranged in sequence from the transparent substrate side. In the fourth embodiment, the etching rate of the lower layer of ZrSi is faster, so that the upper layer contains Zr and the etching rate is made faster. With the above two-layer structure, the phase shift film has a transmittance of 6.4% for light at 365 nm and a phase difference of 185.9°. The back reflectance of the phase shift film is 50.8% for the wavelength 365 nm, 55.2% for the wavelength 405 nm, and 57.6% for the wavelength 436 nm. Further, the reflectance of the back surface of the phase shift film in the wavelength region of 365 nm to 436 nm fluctuated by 6.8%. Therefore, the positional change of the phase shift film pattern caused by the thermal expansion of the phase shift film can be suppressed. In the case of using an etching solution containing ammonium hydrogen fluoride and hydrogen chloride, the ratio of the etching rate of the lower layer to the etching rate of the upper layer was 2.0. Therefore, the cross-sectional shape of the phase shift film pattern after the wet etching is good, and the CD unevenness becomes small. Further, the etching rate of the etching solution containing ammonium hydrogen fluoride and hydrogen chloride to the phase shift film was 0.44 nm/sec. The phase shift mask substrate of Example 4 was produced by the same method as in Example 1 except for the film forming step of the phase shift film. The film formation step of the phase shift film of Example 4 is as follows. First, the transparent substrate is carried into a continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. A ZrSi target (Zr: Si = 1:2) and a Cr target were disposed in the sputtering chamber. Thereafter, a sputtering power of 3.0 kW was applied to the ZrSi target placed in the sputtering chamber, and the Ar gas was introduced into the sputtering chamber at a flow rate of 130 sccm to transport the transparent substrate. When the transparent substrate passes through the vicinity of the ZrSi target, a layer containing a thickness of 18 nm of ZrSi is formed on the main surface of the transparent substrate. Thereafter, a sputtering power of 5.6 kW was applied to the ZrSi target disposed in the sputtering chamber, and Ar gas and O were placed on one side. ₂ Gas and N ₂ The mixed gas of gas becomes 100 sccm, O with Ar gas ₂ The gas becomes 60 sccm, and N ₂ The gas was introduced into the sputtering chamber as the gas flow rate was 40 sccm, and the transparent substrate was transferred. When the transparent substrate passes through the vicinity of the ZrSi target, a film containing ZrSiON having a thickness of 117 nm is formed on the lower layer. A phase shift mask was produced by the same method as in Example 1 using the above phase shift mask substrate. The phase shift film pattern profile of the phase shift mask manufactured using the phase shift mask substrate is slightly eroded at the interface between the layer and the lower layer in the film thickness direction of the phase shift film pattern, but does not affect the characteristics of the mask. . The CD of the phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above is not 45 nm, which is good. The phase shift film pattern of the phase shift mask has a small change in position, and the phase shift film pattern has an excellent pattern cross-sectional shape and excellent CD uniformity. Further, it has been confirmed that the phase shift mask has excellent optical characteristics (back surface reflectance, variation in back surface reflectance, transmittance, and phase difference), so that the positional shift during pattern transfer is also suppressed. And the resolution of the transfer pattern transferred onto the substrate of the display device is improved, and the line having a pattern line width of 1.8 μm and the gap pattern are transferred without causing CD errors. Example 5. Example 5 used TiO ₂ -SiO ₂ The glass substrate serves as a transparent substrate. Therefore, the positional change of the phase shift film pattern caused by the thermal deformation of the transparent substrate can be suppressed. The same as Embodiment 1 except for the transparent substrate. The positional change of the phase shift film pattern of the phase shift mask of the fifth embodiment is smaller than that of the first embodiment, and the phase shift film pattern has excellent pattern cross-sectional shape and excellent CD uniformity, so that it functions as in the first embodiment. Phase shift masks have the same effect. Example 6. Example 6 used TiO ₂ -SiO ₂ The glass substrate serves as a transparent substrate. Therefore, the positional change of the phase shift film pattern caused by the thermal deformation of the transparent substrate can be suppressed. The same as Embodiment 4 except for the transparent substrate. The positional change of the phase shift film pattern of the phase shift mask of Example 6 was small as compared with Example 4. Further, since the phase shift film pattern has an excellent pattern cross-sectional shape and excellent CD uniformity, it exhibits the same effects as those of the phase shift mask of the fourth embodiment. Comparative Example 1. The phase shift film of the phase shift mask substrate of Comparative Example 1 comprises a monolayer film (film thickness: 130 nm) of MoSiON disposed on a transparent substrate. The same as Example 1 except for the phase shift film. The phase shift film has a transmittance of 7.5% for light at 365 nm and a phase difference of 180°. The back reflectance of the phase shifting film is 12.5% for a wavelength of 365 nm, 10.6% for a wavelength of 405 nm, and 11.0% for a wavelength of 436 nm. The etching rate of the etching solution containing ammonium hydrogen fluoride and hydrogen chloride to the phase shift film was 0.03 nm/sec. The phase shift mask base of Comparative Example 1 was produced by the same method as in Example 1 except for the film formation step of the phase shift film. The film formation step of the phase shift film of Comparative Example 1 is as follows. First, the transparent substrate is carried into a continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. A MoSi target (Mo: Si = 1:4) and a Cr target were disposed in the sputtering chamber. Then, a sputtering gas of 5.4 kW was applied to the MoSi target placed in the sputtering chamber, and the mixed gas of the Ar gas and the NO gas was introduced into the sputtering so that the Ar gas became 50 sccm and the NO gas became a flow rate of 40 sccm. The transparent substrate is transferred while being plated. When the transparent substrate passes through the vicinity of the MoSi target, a single-layer phase shift film containing a film thickness of 130 nm of MoSiON is formed on the main surface of the transparent substrate. A phase shift mask was produced by the same method as in Example 1 using the above phase shift mask substrate. The phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above has a tapered cross section, and does not reach a level at which a high-definition phase shift film pattern can be transferred with high precision. The CD of the phase shift film pattern of the phase shift mask manufactured using the phase shift mask substrate described above is not 100 nm, and the level of the high-definition phase shift film pattern can be transferred with high precision. The phase shift film pattern of the phase shift mask has a large change in position, and the pattern cross-sectional shape and CD uniformity of the phase shift film pattern are also insufficient. Therefore, it is difficult to accurately transfer the high-definition phase shift film pattern using the phase shift mask described above. As described above, the present invention has been described in detail based on the embodiments and examples, but the present invention is not limited thereto. It will be appreciated that variations or modifications can be made within the spirit of the present invention as long as they have a general knowledge in the field. The invention having the following constitution can also exert the same effects as the present invention. (Configuration A-1) A phase shift mask substrate characterized in that it is used for phase shifting of a display device having a phase shift film pattern formed on a phase shift mask base transparent substrate by wet etching The photomask further includes a transparent substrate and a phase shift film formed on the transparent substrate, wherein the phase shift film has at least a lower layer having a function of adjusting a reflectance of light incident from the transparent substrate side; and an upper layer And disposed on the upper side of the lower layer and having a function of adjusting transmittance and phase difference of the light to be exposed; wherein the phase shift film has a transmittance of 1% or more for light having a wavelength of 365 nm included in the exposed light. And 50% or less, the phase difference is 160° or more and 200° or less, and the phase shift film has a reflectance of more than 20% in a wavelength region of 365 nm to 436 nm incident from the transparent substrate side, and the upper layer is composed of a metal. And one or both of oxygen and nitrogen, wherein the lower layer is made of a metal-containing material, and the upper layer and the lower layer are formed by patterning the phase shift film. Etching with the same material of the etchant composition, etching rate of the lower layer with respect to the ratio of the etching rate of the upper layer 10 and is less than 1. (Configuration A-2) The phase shift mask substrate constituting A-1 is characterized in that the etching rate of the etching liquid in the phase shift film is 0.06 nm/sec or more and 2.5 nm/sec or less. (Configuration A-3) The phase shift mask substrate constituting A-1 or A-2, characterized in that the material constituting the upper layer is selected from a material containing metal and oxygen, a material containing metal and nitrogen, and a metal. , oxygen and nitrogen materials, materials comprising metals, cerium and oxygen, materials comprising metals, cerium and nitrogen, and materials comprising metals, cerium, oxygen and nitrogen, and additions to the materials such that the phases are displaced The material used for the patterning of the film is a component which has a faster etching rate for the upper layer or a component which is slower. (Configuration A-4) The phase shift mask substrate constituting A-1 or A-2, wherein the material constituting the lower layer is selected from a material containing metal, a material containing metal and tantalum, and A material which is a component which slows the etching rate of the lower layer by the etching liquid used for patterning the phase shift film, or a component which becomes slow is added to the material. (Construction A-5) The phase shift mask substrate according to any one of the items A-1 to A-4, characterized in that the metal contained in the material constituting the upper layer and the material constituting the lower layer are included The metal is at least one selected from the group consisting of titanium, zirconium, molybdenum and niobium. (Construction A-6) The phase shift mask base structure according to any one of the items A-1 to A-5, wherein the metal contained in the material of the upper layer is at least one selected from the group consisting of titanium and zirconium. . (Configuration A-7) The phase shift mask substrate constituting A-4 is characterized in that the metal contained in the material constituting the lower layer is molybdenum, and the component which slows the etching rate of the lower layer is carbon. (Construction A-8) The phase shift mask substrate according to any one of A-1 to A-7, wherein the transparent substrate is made of SiO ₂ -TiO ₂ Made of glass. (Structure A-9) The phase shift mask substrate according to any one of the items A-1 to A-8, characterized in that the light-shielding film formed on the phase shift film is provided. (Configuration A-10) A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and characterized by: a resist pattern forming step, such as forming A-1 a resist pattern formed on the phase shift film of the phase shift mask substrate of any one of A-8; and a phase shift film pattern forming step of using the resist pattern as a mask to perform the phase shift film The phase shift film pattern is formed by wet etching. (Configuration A-11) A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and characterized by: a resist pattern forming step, which is structured as A-9 a resist pattern formed on the light-shielding film of the phase shift mask base; a light-shielding film pattern forming step of wet etching the light-shielding film to form a light-shielding film pattern; and The displacement film pattern forming step of wet etching the phase shift film to form a phase shift film pattern by using the light shielding film pattern as a mask.

10‧‧‧ phase shift mask base

20‧‧‧Transparent substrate

30‧‧‧ phase shift film

30a‧‧‧ phase shift film pattern

31‧‧‧Under

31a‧‧‧lower pattern

32‧‧‧Upper

32a‧‧‧Upper pattern

40‧‧‧Shade film

40a‧‧‧1st light-shielding film pattern

40b‧‧‧2nd shading film pattern

50‧‧‧1st resist pattern

60‧‧‧2nd resist pattern

100‧‧‧ phase shift mask

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the constitution of a film of a phase shift mask base. 2(a) to 2(e) are schematic views showing the steps of manufacturing the phase shift mask.

Claims (15)

A phase shift mask substrate, which is used for manufacturing a phase shift mask for manufacturing a display device having a phase shift film pattern on a transparent substrate, and has a transparent substrate and is formed on the transparent substrate a phase shift film having at least a lower layer having a function of adjusting a reflectance of light incident from the transparent substrate side, and an upper layer disposed on an upper side of the lower layer and having an adjustment for exposure light The function of transmittance and phase difference; the phase shifting film has specific optical characteristics for the transmittance and phase difference of the exposed light, and the phase shifting film is in the wavelength region of 365 nm to 436 nm incident from the transparent substrate side. The reflectance of the light is more than 20%, and the fluctuation range of the reflectance of the light in the wavelength region of 365 nm to 436 nm incident from the transparent substrate side is 10% or less. The phase shift mask substrate according to claim 1, wherein the phase shift film has a transmittance of 1% or more and 50% or less with respect to light of a wavelength of 365 nm included in the exposed light, and a phase difference of 160° or more and 200. ° below. The phase shift mask substrate of claim 1 or 2, wherein said upper layer is composed of a material containing one or both of metal, oxygen and nitrogen, said lower layer being composed of a metal-containing material, said upper layer and said lower layer It is composed of a material which can be etched using the same etching liquid when patterning the phase shift film, and the ratio of the etching rate of the lower layer to the etching rate of the upper layer is more than 1 and 10 or less. The phase shift mask substrate of claim 3, wherein the etching rate of the etching solution of the phase shift film is 0.06 nm/sec or more and 2.5 nm/sec or less. The phase shift mask substrate of claim 1, wherein the material constituting the upper layer is selected from the group consisting of a material containing metal and oxygen, a material containing metal and nitrogen, a material containing metal, oxygen and nitrogen, and a metal, bismuth and oxygen. a material, a material containing metal, niobium and nitrogen, and a material containing metal, antimony, oxygen and nitrogen, and an etching solution for etching the upper layer by using an etching solution used for patterning the phase shifting film A material that has a faster component or a slower component. The phase shift mask substrate of claim 1, wherein the material constituting the lower layer is selected from the group consisting of a metal-containing material, a material containing a metal and a tantalum, and a material added to the material to pattern the phase shift film. The etchant used is a material which has a faster etching rate for the lower layer or a slower component. The phase shift mask substrate according to claim 3, wherein the metal contained in the material constituting the upper layer and the metal contained in the material constituting the lower layer are each at least one selected from the group consisting of titanium, zirconium, molybdenum and tantalum. The phase shift mask substrate of claim 3, wherein the metal contained in the material constituting the upper layer is at least one selected from the group consisting of titanium and zirconium. The phase shift mask substrate according to claim 6, wherein the metal contained in the material constituting the lower layer is molybdenum, and the component which slows the etching rate of the lower layer is carbon. The phase shift mask substrate of claim 1 or 2, wherein the transparent substrate is made of SiO ₂ -TiO ₂ -based glass. A phase shift mask substrate according to claim 1 or 2, comprising a light shielding film formed on said phase shift film. A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and characterized in that: a resist pattern forming step is provided in any one of claims 1 to 10 Forming a resist pattern on the phase shift film of the phase shift mask base; and forming a phase shift film pattern by using the resist pattern as a mask, and performing wet etching on the phase shift film to form a phase shift film pattern . A method of manufacturing a phase shift mask, which is a method of manufacturing a phase shift mask for manufacturing a display device, and characterized by: a resist pattern forming step of a phase shift mask substrate as claimed in claim 11 a light-shielding film pattern forming step of forming a light-shielding film pattern by using the resist pattern as a mask, wet etching the light-shielding film to form a light-shielding film pattern, and a phase shift film pattern forming step. The light-shielding film pattern is used as a mask, and the phase shift film is wet-etched to form a phase shift film pattern. A pattern transfer method characterized in that a phase shift mask obtained by a method of manufacturing a phase shift mask of claim 12 or 13 is irradiated with light to transfer a pattern onto a display device substrate. . The pattern transfer method of claim 14, wherein the exposed light is a composite light comprising light of a plurality of wavelengths selected from a wavelength region of 365 nm to 436 nm.