TW201826010A - Phase shift mask blank and method for manufacturing phase shift mask using same and method for manufacturing display device including a phase shift film arranged on a transparent substrate comprises first and second functional layers and an intermediate layer arranged therebetween - Google Patents

Abstract

The present invention provides a phase shift mask blank for use in manufacturing a phase shift mask for a display device, having excellent pattern cross-sectional profile and excellent CD uniformity and being formed with a fine pattern. A phase shift film arranged on a transparent substrate comprises first and second functional layers and an intermediate layer arranged therebetween. The first and second functional layers comprise a chromium-based material containing chromium, oxygen, and nitrogen, wherein chromium is between 30-70 atom%; oxygen is 20-60 atom%; and nitrogen is 0.4-30 atom%. The content of nitrogen contained in the first functional layer is equal to or greater than the content of nitrogen contained in the second functional layer. The content of oxygen contained in the second functional layer is greater than the content of oxygen contained in the first functional layer. The intermediate layer contains chromium and carbon, and the content of chromium is 55-90 atom% and the content of carbon is 10-45 atom%. The content of chromium contained in the intermediate layer is greater than the contents of chromium contained in the first and second functional layers.

Description

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

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

In recent years, along with the high resolution and high definition of display devices such as FPD (Flat Panel Display, flat panel display), there has been a demand for an excellent pattern cross-sectional shape and excellent CD (Critical Dimension) criticality uniformity. Phase shift mask for fine pattern display devices. In addition, affected by the reduction in price of display devices such as FPD, it is necessary to reduce the manufacturing cost of the phase shift mask. In the case of a previous phase-shifting mask base having a light-shielding film formed on the phase-shifting film, a resist film pattern was used as a mask and the light-shielding film was etched to form a light-shielding film pattern. The light-shielding film pattern is used as a photomask and the phase-shifting film is etched to form a phase-shifting film pattern. Thereafter, the resist film pattern is peeled off, and the light-shielding film pattern is peeled off to produce a phase having the phase-shifting film pattern. Shift the hood. On the other hand, in the case where the phase-shifting mask substrate on which the light-shielding film is not formed on the phase-shifting film, the step of forming the light-shielding film pattern and the peeling step on the phase-shifting film are not required, and the manufacturing cost can be reduced. In response to such a situation in recent years, a phase shift mask for a display device is required, which is manufactured using a phase shift mask substrate on which a light-shielding film is not formed on the phase shift film, and has an excellent pattern cross-sectional shape and Excellent CD uniformity and fine pattern formation. For example, Patent Document 1 proposes a phase shift mask substrate for a display device including a phase shift film having a structure in which two or more thin films are laminated on a transparent substrate. Although the thin films constituting the phase shift film have mutually different compositions, they collectively include substances that can be etched by the same etching solution, and have different etching rates due to different compositions. In Patent Document 1, when the phase shift film is patterned, the etching rate of each thin film constituting the phase shift film is adjusted so that the cross-sectional gradient of the edge portion of the phase shift film pattern is steeply formed. In addition, in Patent Document 1, a phase shift mask substrate for a display device is also proposed, which uses a light-shielding film, a semi-transmissive film, an etching stopper film, and hard light on the upper or lower part of the phase inversion film. The cover film is typically a functional film including one or more of the films necessary for transferring a pattern. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Laid-Open No. 2014-26281

[Problems to be Solved by the Invention] The phase-shifting film used in the phase-shifting reticle for display devices previously proposed does not take into account the laser used in patterning the resist film used to form the phase-shifting film pattern. Designed to affect the resist film due to reflection of drawing light. Therefore, the reflectivity of the phase-shifting film to the laser drawing light exceeds 20%. As a result, there are cases in which a standing wave is generated in the resist film, and as a result, the CD uniformity of the resist film pattern is deteriorated, and even the resist film pattern is patterned to form a photomask. The CD uniformity of the transfer film pattern cannot meet the values required in recent years. Accordingly, the present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a phase-shifting film having a reduced film surface reflectance for light in a wavelength range of 350 nm to 436 nm used as laser drawing light, and to provide a phase shift film Phase shift mask substrate for forming phase shift mask for display device having excellent pattern cross-sectional shape and excellent CD uniformity and forming fine pattern, and method for manufacturing phase shift mask using same . Furthermore, an object is to provide a method for manufacturing a high-resolution and high-definition display device by using a phase shift mask for a display device having an excellent pattern cross-sectional shape and excellent CD uniformity and forming a fine pattern. [Technical means to solve the problem] The present inventors have worked hard in order to achieve the above-mentioned object, and have obtained the following insights: By constituting a phase shift film containing a chromium-based material with at least three layers, the composition of each layer constituting the phase shift film or The film thickness can be studied to reduce the phase shift film's light in the wavelength range from 350 nm to 436 nm while making the transmittance and phase difference of the phase shift film to the exposed light meet the specific optical characteristics required as a phase shift film. The film surface reflectance. This invention is based on this knowledge, and has the following structures. (Composition 1) A phase-shifting mask base characterized in that it is provided on a transparent substrate with a phase-shifting film containing a chromium-based material, and the phase-shifting film has a first functional layer constituting a lower layer and an upper layer thereof. The second functional layer and an intermediate layer disposed between the first functional layer and the second functional layer, the first functional layer and the second functional layer include a chromium-based material containing chromium, oxygen, and nitrogen, and chromium It is 30 to 70 atomic%, oxygen is 20 to 60 atomic%, and nitrogen is 0.4 to 30 atomic%. The content rate of nitrogen contained in the first functional layer is the same as or more than that contained in the second functional layer. The content of nitrogen is greater than the content of oxygen contained in the first functional layer. The intermediate layer contains chromium and carbon. The content of chromium is 55 to 90. Atomic%, the content of carbon is 10 to 45 atomic%, and the content of chromium contained in the intermediate layer is more than the content of chromium contained in the first functional layer and the second functional layer. (Structure 2) The phase-shifting mask substrate described in Structure 1, wherein the first functional layer has a function of mainly adjusting a transmittance and a phase difference of light to be exposed, and the second functional layer has a function of reducing The function of the reflectance of light incident on the phase shift film side is that the film thickness of the first functional layer is thicker than the film thickness of the second functional layer. (Structure 3) The phase shift mask substrate according to Structure 1 or 2, characterized in that the first functional layer includes a chromium nitride, and the second functional layer includes a chromium oxide obtained by bonding chromium with oxygen ( III). (Composition 4) The phase shift mask substrate according to any one of constitutions 1 to 3, wherein the intermediate layer further includes a chromium-based material containing oxygen, the first functional layer, the intermediate layer, and the above The second functional layer contains chromium (III) oxide. (Composition 5) The phase shift mask substrate according to any one of constitutions 1 to 4, wherein the film surface reflectance of the phase shift film to light incident from the phase shift film side is 350 to 436 nm. In the wavelength region, it is 15% or less. (Structure 6) The phase-shift mask base according to any one of Structures 1 to 5, characterized in that the back surface reflectance of the phase-shift film to light incident from the transparent substrate side is at a wavelength of 313 to 436 nm. In the area, it is 20% or less. (Structure 7) The phase shift mask substrate according to any one of Structures 1 to 6, wherein a light-shielding film pattern is provided between the transparent substrate and the phase shift film. (Composition 8) A method of manufacturing a phase shift mask, which is characterized by having the following steps: On the above-mentioned phase shift film of the phase shift mask base described in any one of 1 to 7, A step of forming a resist film pattern by drawing processing and developing processing of laser light in any wavelength range from 350 nm to 436 nm; and using the resist film pattern as a photomask and comparing the above-mentioned phase The step of performing a shift film etching, and forming a phase shift film pattern on the transparent substrate. (Composition 9) A method for manufacturing a display device, which is characterized by having the following steps: a step of placing a phase shift mask manufactured by the method for manufacturing a phase shift mask described in configuration 8 on a mask stage of an exposure device; And a step of irradiating the phase shift mask with exposure light, and transferring the phase shift film pattern to a resist film formed on a display device substrate. (Structure 10) The manufacturing method of the display device according to Structure 9, wherein the exposed light is a composite light of a plurality of wavelengths of light selected from a wavelength range of 313 nm to 436 nm. [Effects of the Invention] As described above, the phase shift mask base of the present invention includes a phase shift film containing a chromium-based material on a transparent substrate, and the phase shift film has a first functional layer constituting an upper layer and a lower layer thereof. The second functional layer and an intermediate layer disposed between the first functional layer and the second functional layer, the first functional layer and the second functional layer include a chromium-based material containing chromium, oxygen, and nitrogen, and chromium It is 30 to 70 atomic%, oxygen is 20 to 60 atomic%, and nitrogen is 0.5 to 30 atomic%. The content rate of nitrogen contained in the first functional layer is the same as or more than that contained in the second functional layer. The content rate of nitrogen, the content rate of oxygen contained in the second functional layer is higher than the content rate of oxygen contained in the first functional layer, the intermediate layer contains chromium and carbon, and the content rate of chromium is 55 to 90. Atomic%, the content of carbon is 10 to 45 atomic%, and the content of chromium contained in the intermediate layer is more than the content of chromium contained in the first functional layer and the second functional layer. Therefore, using this phase shift mask substrate, a phase shift mask having excellent pattern cross-sectional shape and excellent CD uniformity and having a fine pattern formed can be manufactured. Moreover, by using this phase shift mask, a high-resolution and high-definition display device can be manufactured.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following embodiment is an embodiment when the present invention is embodied, and the present invention is not limited to the scope thereof. In addition, in the drawings, the same or equivalent parts may be denoted by the same reference numerals and the description thereof may be simplified or omitted. Embodiment 1. In Embodiment 1, a phase shift mask base will be described. FIG. 1 is a schematic view showing a film configuration of a phase shift mask substrate 10. The phase shift mask base 10 includes a transparent substrate 20 that is transparent to the exposed light, and a phase shift film 30 made of a chromium-based material disposed on the transparent substrate 20. When it is assumed that there is no surface reflection loss, the transparent substrate 20 has a transmittance of 85% or more for the exposed light, and preferably has a transmittance of 90% or more. The phase shift film 30 includes, from the transparent substrate 20 side, a phase shift layer 31 as a first functional layer constituting a lower layer thereof, a reflectance reducing layer 32 as a second functional layer constituting an upper layer thereof, and as a phase shift layer 31 and The metal layer 33 is an intermediate layer between the reflectance reducing layers 32. Each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 is formed of a chromium-based material containing chromium (Cr). Therefore, the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 can be etched by the same etching solution. The phase shift layer 31 is disposed on the main surface of the transparent substrate 20. The phase shift layer 31 has a function of mainly adjusting the transmittance and the phase difference of the exposed light. The phase shift layer 31 is a layer having the thickest film thickness in the phase shift film 30 compared with the film thickness of the reflectance reduction layer 32 and the metal layer 33. The content ratios of the elements constituting the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 described below are values measured by X-ray photoelectron spectroscopy (XPS, ESCA). The phase shift layer 31 contains a chromium-based material containing chromium (Cr), oxygen (O), and nitrogen (N). As for the average content of each element, chromium is 30 to 70 atomic%, oxygen is 20 to 60 atomic%, and nitrogen It is 0.4 to 30 atomic%. The phase shift layer 31 preferably contains chromium from the viewpoint of forming an excellent pattern cross-sectional shape by wet etching in the form of a bonded state (chemical state) of the components constituting the phase shift layer 31. Chromium nitride bonded to nitrogen, especially containing chromium mononitride (CrN) or dichromium nitride (Cr ₂ N). Furthermore, the phase shift layer 31 may be a chromium-based material containing at least one of carbon (C) and fluorine (F). Examples of the material for forming the phase shift layer 31 include CrON, CrOCN, and CrFCON. The phase shift layer 31 can be formed by a sputtering method. The reflectance reduction layer 32 is disposed on the upper side of the phase shift layer 31. The reflectance reducing layer 32 mainly has a function of reducing the reflectance of light incident on the side of the phase shift film 30 (that is, the side of the reflectance reducing layer 32 opposite to the transparent substrate 20 side). The reflectance-reducing layer 32 is for reducing the reflectance of the phase-shifting film 30 by the reflection effect generated by the interface between the metal layer 33 and the reflectance-reducing layer 32 and the reflection generated by the surface of the reflectance-reducing layer 32. And the film thickness adjustment layer. The reflectance-reducing layer 32 contains a chromium-based material containing chromium (Cr), oxygen (O), and nitrogen (N). As for the average content of each element, chromium is 30 to 70 atomic%, and oxygen is 20 to 60 atomic%. Nitrogen is 0.4 to 30 atomic%. The reflectance-reducing layer 32 is preferable from the viewpoint of obtaining an excellent pattern cross-sectional shape by wet etching in the form of the bonding state (chemical state) of the components constituting the reflectance-reducing layer 32. Chromium oxide containing chromium and oxygen bond, especially chromium (III) oxide (Cr ₂ O ₃ ). Further, the reflectance reducing layer 32 may be a chromium-based material containing at least one of carbon (C) and fluorine (F). For example, examples of the material for forming the reflectance-reducing layer 32 include CrON, CrOCN, and CrFON. From the viewpoint of reducing the reflectance of light incident from the phase shift film 30 side (the surface side of the reflectance reduction layer 32), and forming an excellent pattern cross-sectional shape by wet etching as a whole of the phase shift film 30 In other words, it is assumed that the content rate of nitrogen (N) included in the phase shift layer 31 is the same as or more than the content rate of nitrogen (N) included in the reflectance reduction layer 32, and that the reflectance reduction layer 32 contains A state where the content rate of oxygen (O) is higher than the content rate of oxygen (O) contained in the phase shift layer 31. In terms of the effect of reducing the reflectance of the film surface, it is preferable that the content of oxygen (O) contained in the reflectance-reducing layer 32 is higher than the content of oxygen (O) contained in the phase-shift layer 31. The ratio is at least 1 atomic% or more, preferably 5 atomic% or more. The reflectance reduction layer 32 can be formed by a sputtering method. The metal layer 33 is disposed between the phase shift layer 31 and the reflectance reduction layer 32. The metal layer 33 has a function of adjusting the transmittance to the exposed light, and has a function of reducing the reflectance to the light incident from the phase shift film 30 side in combination with the reflectance reducing layer 32. Furthermore, it has a function of reducing the reflectance of light incident from the transparent substrate 20 side in combination with the phase shift layer. The metal layer 33 contains chromium (Cr) and carbon (C). Regarding the average content of each element, the content of chromium (Cr) is 55 to 90 atomic%, and the content of carbon (C) is 10 to 45 atomic%. Furthermore, in terms of the relationship between the metal layer 33 and the phase shift layer 31 and the reflectance reduction layer 32, the content of chromium contained in the metal layer 33 is higher than that of the chromium contained in the phase shift layer 31 and the reflectance reduction layer 32. Containing rate. By setting the content ratio of carbon (C) to 10 atomic% or more, it is possible to suppress corrosion of the cross-sectional shape of the metal layer 33 caused by an increase in the side etching rate. Further, by setting the content of carbon (C) to 45 atomic% or less, the cross-sectional shape of the metal layer 33 can be suppressed from becoming a tapered shape. By setting the content ratio of carbon (C) contained in the metal layer 33 to the above-mentioned appropriate range, a pattern can be formed on the metal layer 33 by an appropriate photomask process. The metal layer 33 may be a chromium-based material containing at least one of nitrogen (N), oxygen (O), and fluorine (F). Examples of the material for forming the metal layer 33 include CrC, CrCN, CrCO, CrCF, and CrCON. Among them, the metal layer 33 is preferably a chromium-based material containing chromium (Cr), carbon (C), and oxygen (O). Furthermore, from the viewpoint of obtaining an excellent pattern cross-sectional shape by wet etching in the form of the bonding state (chemical state) of the components constituting the phase shift layer 31, the reflectance reducing layer 32, and the metal layer 33, It is further preferred that chromium (III) oxide (Cr ₂ O ₃ ). By providing the metal layer 33, the sheet resistance of the phase-shifting film is reduced, so that the charge accumulation of the phase-shifting mask substrate and the phase-shifting mask can be prevented. When the metal layer 33 is not provided, the electricity generated when the phase-shift mask base and the phase-shift mask are moved in and out of the housing will not leak out, and the electricity will be stored in the phase-shift mask base and the phase-shift mask. Easy to adhere to foreign objects. In addition, when a relatively small pattern is formed in the phase shift mask, the electricity jumps from the pattern to the pattern, which is likely to cause electrostatic damage. The metal layer 33 can be formed by a sputtering method. The metal layer 33 preferably has a higher extinction coefficient than the reflectance reduction layer 32 in the wavelength region of 350 nm to 436 nm. In addition, it is preferable to have an extinction coefficient higher than the extinction coefficient of the reflectance reduction layer 32 in the wavelength region of 313 nm to 436 nm. The difference between the extinction coefficient of the metal layer 33 and the extinction coefficient of the reflectance reduction layer 32 is preferably 1.5 to 3.5, and more preferably 1.8 to 3.5. If the difference in extinction coefficient is 1.5 to 3.5, it is possible to increase the range of the above-mentioned wavelength region (wavelength region of 350 nm to 436 nm, or wavelength region of 313 nm to 436 nm) of the interface between the metal layer 33 and the reflectance reduction layer 32. The reflectance is more preferable because it further exhibits the effect of reducing the reflectance. In addition, the metal layer 33 preferably has an extinction coefficient higher than that of the phase shift layer 31 in a wavelength region of 350 nm to 436 nm. In addition, it is preferable to have an extinction coefficient higher than the extinction coefficient of the phase shift layer 31 in the wavelength region of 313 nm to 436 nm. The extinction coefficient can be measured using an n & k analyzer or an ellipsometer. The metal layer 33 has a chromium (Cr) content rate (atomic%) higher than the chromium (Cr) content rate (atomic%) of the phase shift layer 31 and the reflectance reduction layer 32. The difference between the average Cr content rate of the metal layer 33 and the average Cr content rate of the phase shift layer 31 and the reflectance reduction layer 32 is preferably 10 to 80 atomic%, more preferably 15 to 80 atomic%. If the difference in the average Cr content is 10 to 80 atomic%, the above-mentioned wavelength region (a wavelength region of 350 nm to 436 nm, or a wavelength of 313 nm to 436 nm) of the interface between the metal layer 33 and the reflectance reduction layer 32 can be increased. Area), it is preferable to further exhibit the reflectance reduction effect. The difference between the average Cr content rate of the metal layer 33 and the average Cr content rate of the phase shift layer 31 and the reflectance reduction layer 32 is more preferably 15 to 60 atomic%, and more preferably 20 to 50 atomic%. By setting the difference between the average Cr content ratios to the above range, the above-mentioned wavelength region (wavelength region of 350 nm to 436 nm) of the interface between the metal layer 33 and the reflectance reduction layer 32 is exerted on light incident from the side of the reflectance reduction layer. Or in the wavelength range of 313 nm to 436 nm), in addition to the above-mentioned wavelength range (313 nm to 436) of the interface between the metal layer 33 and the phase shift layer 31 for light incident from the transparent substrate side In the wavelength range of nm), the effect of reducing the reflectance is preferable. The etching rate of the metal layer 33 can be adjusted by making chromium (Cr) a nitrogen-based material by containing nitrogen (N), oxygen (O), carbon (C), and fluorine (F). For example, when chromium (Cr) contains carbon (C) or fluorine (F), the wet etching speed can be reduced, and when chromium (Cr) contains nitrogen (N) or oxygen (O), the wet etching can be accelerated Etching speed. In consideration of the wet etching speed with the phase shift layer 31 and the reflectance reduction layer 32 formed above and below the metal layer 33, by adding the above elements to chromium to make it a chromium-based material, the phase shift after etching can be made. The cross-sectional shape of the film 30 becomes favorable. Each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 preferably has a refractive index of 2.0 or more in a wavelength region of 350 nm to 436 nm. If it has a refractive index of 2.0 or more, in order to obtain the required optical characteristics (transmittance and phase difference), the required film thickness of the phase shift film 30 can be made thin. Therefore, a phase shift mask made using the phase shift mask substrate 10 provided with the phase shift film 30 can be provided with a phase shift film pattern having excellent pattern cross-sectional shape and excellent CD uniformity. The refractive index can be measured using an n & k analyzer or an ellipsometer. With the laminated structure of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32, the transmittance and phase difference of the phase shift film 30 to the exposed light have specific optical characteristics. 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 1% to 30%, more preferably 2% to 20%, and more preferably than 2% to 20% of light of a specific wavelength (hereinafter referred to as a representative wavelength) included in the exposed light. It is preferably 3% to 10%. That is, when the exposed light is a composite light including 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 included in its wavelength range. For example, when the exposed light is a composite light including j-line, i-line, h-line, and g-line, the phase shift film 30 has the above-mentioned transmission for any of the j-line, i-line, h-line, and g-line. rate. 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 ° with respect to light having a representative wavelength included in the exposed light. Because of this property, it is possible to change the phase of light of a representative wavelength included in the exposed light by 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 including 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 included in its wavelength range. For example, when the exposed light is a composite light including j-line, i-line, h-line, and g-line, the phase shift film 30 has the above-mentioned phase for any one of j-line, i-line, h-line, and g-line. difference. The transmittance and phase difference of the phase shift film 30 can be controlled by adjusting the composition and thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 constituting the phase shift film 30. Therefore, in this embodiment, the composition and thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 are adjusted so that the transmittance and phase difference of the phase shift film 30 have the above-mentioned specific optical characteristics. Moreover, the transmittance of the phase shift film 30 is mainly affected by the composition and thickness of the phase shift layer 31 and the metal layer 33. The refractive index of the phase shift film 30 is mainly affected by the composition and thickness of the phase shift layer 31. The transmittance and phase difference can be measured using a phase shift amount measuring device or the like. The film surface reflectance of the phase shift film 30 with respect to light incident from the phase shift film 30 side is 15% or less in a wavelength region of 350 nm to 436 nm. The wavelength range of 313 nm to 436 nm is preferably 22.5% or less. That is, the film surface reflectance of the phase shift film 30 to light incident from the phase shift film 30 side is 15% or less in a wavelength range of 350 nm to 436 nm, and it is preferable to expand the wavelength range to 313 nm to 436. nm is also below 22%. If the film surface reflectance of the phase shift film 30 is 15% or less in the wavelength region of 350 nm to 436 nm, the film surface reflectance of the laser drawing light is reduced, so that a phase shift having excellent CD uniformity can be formed Photomask. In addition, if the film surface reflectance of the phase shift film 30 is 22.5% or less in the wavelength range of 313 nm to 436 nm, the film surface reflectance of the exposed light is reduced, so the pattern formed on the phase shift mask is transferred. In this case, blurring (glare) of the transfer pattern caused by the reflected light from the display device substrate can be prevented. The film surface reflectance of the phase shift film 30 is preferably in the range of 313 nm to 436 nm, preferably 20% or less, and further preferably 15% or less. The fluctuation range of the film surface reflectance of the phase shift film 30 is preferably 9% or less in the wavelength region of 350 nm to 436 nm, and more preferably 8.5% or less. In the wavelength region of 313 nm to 436 nm, it is preferably 12.5% or less, and more preferably 12%. That is, the fluctuation range of the film surface reflectance of the phase shift film 30 is preferably 9% or less in the wavelength region of 350 nm to 436 nm, and more preferably 8.5% or less. 313 nm to 436 nm is also below 12.5%, and further below 12%. The film surface reflectance of the phase shift film 30 and its fluctuation range can be controlled by adjusting the refractive index, extinction coefficient, and thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 constituting the phase shift film 30. . The extinction coefficient and refractive index can be controlled by adjusting the composition. Therefore, in this embodiment, the phase shift layer 31 and the metal layer 33 are adjusted in such a manner that the film surface reflectance of the phase shift film 30 and its fluctuation range have the specific physical properties described above. And the composition and thickness of each of the reflectance reducing layers 32. In addition, the film surface reflectance of the phase shift film 30 and its fluctuation range are mainly affected by the composition and thickness of each of the metal layer 33 and the reflectance reduction layer 32. The film surface reflectance can be measured using a spectrophotometer or the like. The variation range of the reflectance of the film surface is obtained from the difference between the maximum reflectance and the minimum reflectance in a wavelength region of 350 nm to 436 nm or 313 nm to 436 nm. The phase shift layer 31 may be a case including a single film having a uniform composition, a case including a plurality of films having different compositions, or a case including a single film whose composition is continuously changed in the thickness direction. The same applies to the metal layer 33 and the reflectance reducing layer 32. Further, each element constituting each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 23 may be formed at the interface between the phase shift layer 31 and the metal layer 33, and at the interface between the metal layer 33 and the reflectance reduction layer 32. The composition gradient region of the composition gradient. Furthermore, in the composition gradient region, the composition gradient may be continuously formed throughout the entire region, or the composition gradient may be formed stepwise, and further, the composition gradient may be formed stepwise in one part, and continuously formed in the other part. FIG. 2 is a schematic view showing the structure of another film of the phase shift mask base 10. As shown in FIG. 2, the phase shift mask base 10 may be provided with a light-shielding film pattern 40 between the transparent substrate 20 and the phase shift film 30. When the phase shift mask substrate 10 includes a light-shielding film pattern 40, the light-shielding film pattern 40 is disposed on the main surface of the transparent substrate 20. The light-shielding film pattern 40 has a function of blocking the transmission of the exposed light. The material for forming the light-shielding film pattern 40 is not particularly limited as long as it has a function of blocking the transmission of the exposed light. Examples include chromium-based materials. Examples of the chromium-based material include chromium (Cr) or a chromium-based material containing at least one of chromium (Cr) and carbon (C) and nitrogen (N). Other examples include chromium-based materials containing chromium (Cr) and at least one of oxygen (O) and fluorine (F), or chromium (Cr), carbon (C), and nitrogen (N). A chromium-based material containing at least one of oxygen (O) and fluorine (F). For example, examples of a material for forming the light-shielding film pattern 40 include Cr, CrC, CrN, and CrCN. The light-shielding film pattern 40 can be formed by patterning a light-shielding film formed by a sputtering method by etching. In a portion where the phase shift film 30 and the light-shielding film pattern 40 are laminated, the optical density of the exposed light is preferably 3 or more, and more preferably 3.5 or more. The optical density can be measured using a spectrophotometer or an OD (Optical Density) meter. The light-shielding film pattern 40 may be a case where a single film having a uniform composition is included, a case where a plurality of films having different compositions are included, or a case where a single film whose composition is continuously changed in the thickness direction is included. Furthermore, the phase shift mask base 10 may include a resist film on the phase shift film 30. Next, a method for manufacturing the phase shift mask base 10 according to this embodiment will be described. The phase shift mask substrate 10 is manufactured by performing the following preparation steps and a phase shift film formation step. Hereinafter, each step will be described in detail. 1. Preparation Step In the preparation step, first, the transparent substrate 20 is prepared. The material of the transparent substrate 20 is not particularly limited as long as it is a material that is transparent to the light used for exposure. Examples include synthetic quartz glass, soda lime glass, and alkali-free glass. When a phase-shifting mask base 10 having a light-shielding film pattern 40 is manufactured, a light-shielding film containing, for example, a chromium-based material is formed on the transparent substrate 20 by a sputtering method. Thereafter, a resist film pattern is formed on the light-shielding film, the resist film pattern is used as a photomask, and the light-shielding film is etched to form a light-shielding film pattern 40. After that, the resist film pattern was peeled. 2. Phase shift film forming step In the phase shift film forming step, a phase shift film 30 containing a chromium-based material is formed on the transparent substrate 20 by a sputtering method. Here, when the light-shielding film pattern 40 is formed on the transparent substrate 20, the phase shift film 30 is formed so as to cover the light-shielding film pattern 40. The phase shift film 30 is formed by forming a phase shift layer 31 on the main surface of the transparent substrate 20, forming a metal layer 33 on the phase shift layer 31, and forming a reflectance reducing layer 32 on the metal layer 33. The film formation of the phase shift layer 31 is performed using a sputtering target containing chromium or a chromium-based material in a sputtering gas atmosphere. The sputtering gas atmosphere includes, for example, a material selected from the group consisting of helium, neon, argon, krypton, and An inert gas of at least one of the group consisting of xenon gas, and one containing at least one selected from the group consisting of oxygen, nitrogen, nitrogen monoxide gas, nitrogen dioxide gas, carbon dioxide gas, hydrocarbon-based gas, and fluorine-based gas Mixed gas of active gas. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. As the sputtering target, in addition to chromium metal, chromium-based materials such as chromium oxide, chromium nitride, chromium oxynitride, and chromium carbonitride can be used. Similarly, the metal layer 33 is formed using a sputtering target containing chromium or a chromium-based material in a sputtering gas atmosphere. The sputtering gas atmosphere includes, for example, An inert gas including at least one of the group consisting of gas and xenon, or an inert gas including at least one selected from the group consisting of helium, neon, argon, krypton, and xenon, and including an oxygen selected from the group consisting of oxygen Mixed gas of at least one of nitrogen, nitrogen monoxide gas, nitrogen dioxide gas, carbon dioxide gas, hydrocarbon-based gas, and fluorine-based gas. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. As the sputtering target, in addition to chromium metal, chromium-based materials such as chromium oxide, chromium nitride, chromium oxynitride, and chromium carbonitride can be used. Similarly, the film formation of the reflectance-reducing layer 32 is performed using a sputtering target containing chromium or a chromium-based material in a sputtering gas atmosphere including, for example, An inert gas of at least one of the group consisting of Krypton, Krypton and Xenon, and a group selected from the group consisting of oxygen, nitrogen, nitrogen monoxide gas, nitrogen dioxide gas, carbon dioxide gas, hydrocarbon-based gas, and fluorine-based gas A mixture of at least one active gas. Examples of the hydrocarbon-based gas include methane gas, butane gas, propane gas, and styrene gas. As the sputtering target, in addition to chromium metal, chromium-based materials such as chromium oxide, chromium nitride, chromium oxynitride, and chromium carbonitride can be used. When forming the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32, the composition and thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 are based on the transmittance and phase of the phase shift film 30. The difference is adjusted in such a manner that the specific optical characteristics described above and the film surface reflectance of the phase shift film 30 and its fluctuation range have the specific physical properties described above. The composition of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 can be controlled according to the composition and flow rate of the sputtering gas. The thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 can be controlled according to sputtering power, sputtering time, and the like. When the sputtering device is a continuous sputtering device, the thickness of each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 can be controlled according to the substrate transfer speed. When the phase shift layer 31 includes a single film or a plurality of films having a uniform composition, the above-described film forming process is performed only once or a plurality of times without changing the composition and flow rate of the sputtering gas. In the case where the phase shift layer 31 includes a plurality of films having different compositions, the composition and flow rate of the sputtering gas are changed for each film forming process, and the film forming process is performed a plurality of times. When the phase shift layer 31 includes a single film whose composition is continuously changed in the thickness direction, the film forming process described above is performed only once while changing the composition and flow rate of the sputtering gas. The same applies to the film formation of the metal layer 33 and the film formation of the reflectance reduction layer 32. In the case of performing a plurality of film formation processes, the sputtering power applied to the sputtering target can be reduced. The phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 are preferably formed using a continuous sputtering device, and the film is continuously formed without taking the transparent substrate 20 out of the device and exposing it to the atmosphere. By continuously forming a film without taking it out of the device, it is possible to prevent the surface oxidation or surface carbonization of each unexpected layer. Unexpected surface oxidation or surface carbonization of each layer changes the laser light used when drawing the resist film formed on the phase shift film 30 or transfers the phase shift film pattern on the display device substrate The reflectivity of the exposed light used in the resist film may be changed, or the etching rate of the oxidized portion or the carbonized portion may be changed. When a phase shift mask substrate 10 including a resist film is manufactured, a resist film is next formed on the phase shift film. Regarding the phase shift mask base 10 of the first embodiment, a phase shift film 30 made of a chrome-based material provided on a transparent substrate 20 includes: a phase shift layer 31; a reflectance reduction layer 32; and a metal layer 33 provided on Between the phase shift layer 31 and the reflectance reduction layer 32, in the wavelength region of 350 nm to 436 nm, it has a higher extinction coefficient than that of the reflectance reduction layer 32; the phase shift film 30 transmits the exposed light The rate and phase difference satisfy specific optical characteristics required for the phase shift film 30, and the film surface reflectance of the phase shift film 30 is 15% or less in a wavelength region of 350 nm to 436 nm. Therefore, using the phase shift mask substrate 10, a phase shift mask having an excellent pattern cross-sectional shape and excellent CD uniformity and having a fine pattern formed can be manufactured. In addition, regarding the phase shift mask base 10 of the first embodiment, a phase shift film 30 made of a chromium-based material provided on a transparent substrate 20 includes a phase shift layer 31, a reflectance reduction layer 32, and a metal layer 33. It is located between the phase shift layer 31 and the reflectance reduction layer 32, and has a higher chromium content than the chromium content of the reflectance reduction layer 32. The phase shift film 30 has a transmittance and a phase difference with respect to the exposed light that satisfy the phase. Specific optical characteristics required for the shift film 30, and the film surface reflectance of the phase shift film 30 is 15% or less in a wavelength region of 350 nm to 436 nm. Therefore, using the phase shift mask substrate 10, a phase shift mask having an excellent pattern cross-sectional shape and excellent CD uniformity and having a fine pattern formed can be manufactured. In the phase shift mask base 10 of the first embodiment, the back surface reflectance of the phase shift film is 20% or less in a wavelength region of 365 to 436 nm. Therefore, it is possible to suppress the influence of reflection on the exposure device side, and therefore, it is possible to manufacture a phase-shifting photomask that can perform pattern transfer with high accuracy. Embodiment 2. In Embodiment 2, the manufacturing method of a phase shift mask is demonstrated. The phase shift mask substrate is manufactured by performing the following resist film pattern formation steps and phase shift film pattern formation steps. Hereinafter, each step will be described in detail. 1. Resist film pattern forming step In the resist film pattern forming step, first, a resist film is formed on the phase shift film 30 of the phase shift mask base 10 of Embodiment 1. However, when the phase shift mask base 10 is provided with a resist film on the phase shift film 30, the formation of the resist film is not performed. The material of the resist film used is not particularly limited. It suffices that it is sensitive to laser light having a wavelength selected from a wavelength range of 350 nm to 436 nm described below. The resist film may be any of a positive type and a negative type. Thereafter, a specific pattern is drawn on the resist film using laser light having any wavelength selected from a wavelength range of 350 nm to 436 nm. 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 using a specific developing solution, and a resist film pattern is formed on the phase shift film 30. 2. Phase shift film pattern formation step In the phase shift film pattern formation step, first, a resist film pattern is used as a photomask and the phase shift film 30 is etched to form a phase shift film pattern. Each of the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 constituting the phase shift film 30 is formed of a chromium-based material containing chromium (Cr). Therefore, the phase shift layer 31, the metal layer 33, and the reflectance reduction layer 32 can be etched by the same etching medium (etching solution, etching gas). The etching medium (etching solution, etching gas) for etching the phase shift film 30 is not particularly limited as long as it can selectively etch the phase shift film 30. Specific examples include an etching solution containing cerium ammonium nitrate and perchloric acid, or an etching gas containing a mixed gas of chlorine gas and oxygen. Thereafter, the resist film pattern is peeled using a resist stripping solution or by ashing. According to the method for manufacturing a phase shift mask according to the second embodiment, a phase shift mask having excellent pattern cross-sectional shape and excellent CD uniformity and having a fine pattern can be manufactured. Embodiment 3. In Embodiment 3, the manufacturing method of a display device is demonstrated. The display device is manufactured by performing the following mask mounting step and 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 via the projection optical system of the exposure device. 2. Pattern transfer step In the pattern transfer step, the phase shift mask is irradiated with exposure light, and the phase shift film pattern is transferred to a resist film formed on a display device substrate. The exposed light is a composite light including a plurality of wavelengths of light selected from a wavelength range of 313 nm to 436 nm, or a single selected by cutting a wavelength range from the wavelength range of 313 nm to 436 nm using a filter or the like. Shade. For example, the exposed light is a composite light including i-line, h-line, and g-line, or a mixed light including j-line, i-line, h-line, and g-line, or a monochromatic light of i-line. If the composite light is used as the light for the exposure, the intensity of the exposed light can be increased to increase the productivity, and thus the manufacturing cost of the display device can be reduced. Furthermore, since the phase shift film has a phase shift mask with a backside reflectance of 20% or less in the wavelength range of 365 to 436 nm, the influence of reflection on the exposure device side can be suppressed, and it can be formed on the display device substrate. The resist film is subjected to high-precision pattern transfer. According to the method for manufacturing a display device according to the third embodiment, a high-resolution and high-definition display device can be manufactured. [Examples] Hereinafter, the present invention will be described more specifically based on examples and comparative examples. The following embodiment is an example of the present invention and does not limit the present invention. The phase shift mask bases of Examples 1 to 3 and Comparative Example 1 include a transparent substrate and a phase shift film made of a chromium-based material and disposed on the transparent substrate. 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. FIG. 3 shows the reflectance spectrum of the film surface of the phase-shifting film of the phase-shift mask substrate in Examples 1, 2, 3, and Comparative Example 1, and FIG. 4 shows the phase shifts in Examples 1, 2, 3, and Comparative Example 1. Backside reflectance spectrum of a phase-shifting film on a reticle substrate. FIG. 5 is a graph showing a composition analysis result of a depth direction of a phase shift film of a phase shift mask substrate in Example 1. FIG. FIG. 6 is a graph showing a composition analysis result in a depth direction of a phase shift film of a phase shift mask substrate in Example 2. FIG. FIG. 7 is a graph showing a composition analysis result in a depth direction of a phase shift film of a phase shift mask substrate in Example 3. FIG. Hereinafter, Examples 1 to 3 and Comparative Example 1 will be described in detail. Embodiment 1. The phase-shifting film in the phase-shifting mask substrate of Embodiment 1 includes a phase-shifting layer, a metal layer, and a reflectance reducing layer sequentially arranged from the transparent substrate side, and further, between the phase-shifting layer and the metal layer A composition gradient region is formed at the interface, the interface between the metal layer and the reflectance reducing layer (see FIG. 5). The phase shift mask substrate of Example 1 was manufactured by the following method. First, a synthetic quartz glass substrate is prepared as a transparent substrate. Both main surfaces of the transparent substrate are mirror-polished. Both major surfaces of the transparent substrates prepared in Examples 2, 3, and Comparative Example 1 were similarly mirror-polished. Next, the transparent substrate was carried into a continuous sputtering apparatus. A sputtering chamber is provided in the continuous sputtering apparatus. Next, a 2.7 kW sputtering power was applied to the chromium target placed in the sputtering chamber, while Ar gas, N ₂ Gas, CO ₂ Gas and O ₂ The mixed gas of the gas is introduced into the sputtering chamber, and the transparent substrate is conveyed at a speed of 200 mm / min. Here, the mixed gas system uses Ar as 35 sccm, N ₂ Becomes 35 sccm, CO ₂ Becomes 13 sccm, O ₂ A flow rate of 10 sccm was introduced into the sputtering chamber. When the transparent substrate passes near the chromium target, a phase shift layer including a chromium-based material (CrCON) containing Cr, C, O, and N is formed on the transparent substrate. Next, a sputtering power of 0.6 kW was applied to the chromium target, while Ar gas and CH ₄ Gas mixture gas (Ar gas contains CH at a concentration of 4% ₄ The mixed gas of the gas) is introduced into the sputtering chamber, and the transparent substrate is conveyed at a speed of 400 mm / min. When the transparent substrate passes near the chromium target, a metal layer including a chromium-based material (CrC) containing Cr and C is formed on the phase shift layer. Next, a sputtering power of 3.3 kW was applied to the chromium target, while Ar gas, N ₂ Gas, CO ₂ Gas and O ₂ The mixed gas of the gas is introduced into the sputtering chamber, and the transparent substrate is conveyed at a speed of 400 mm / min. When the transparent substrate passes near the chromium target, a reflection-reducing layer including a chromium-based material (CrCON) containing Cr, C, O, and N is formed on the metal layer. Here, the mixed gas system uses Ar as 35 sccm, N ₂ Becomes 35 sccm, CO ₂ Becomes 13 sccm, O ₂ A flow rate of 9 sccm was introduced into the sputtering chamber. Next, the transparent substrate on which the phase shift film including the phase shift layer, the metal layer, and the reflectance reduction layer is formed is taken out from the continuous sputtering apparatus and washed. Furthermore, the film formation of the phase shift layer, the film formation of the metal layer, and the film formation of the reflectance reduction layer are performed under the condition that the transparent substrate is not taken out of the continuous sputtering device and is exposed to the atmosphere. The inside of a continuous-type sputtering apparatus is performed continuously. Since the phase shift film including the phase shift layer, the metal layer, and the reflectance reduction layer of Example 1 was formed in a continuous sputtering apparatus, the interface between the phase shift layer and the metal layer, the metal layer, and the reflectance reduction layer were formed. The interface is formed with a composition gradient region in which elements constituting each layer continuously form a composition gradient. Regarding the phase shift film of Example 1, the results of measuring the composition in the depth direction by X-ray photoelectron spectroscopy (ESCA) are shown in FIG. 5. The phase shift layer contains a chromium-based material containing chromium (Cr), oxygen (O), nitrogen (N), and carbon (C). The average content of each element is Cr: 49.8 atomic%, O: 40.0 atomic%, and N: 8.2 atomic%, C: 2.0 atomic%. The metal layer contains a chromium-based material containing chromium (Cr), carbon (C), and oxygen (O), and the average content of each element is Cr: 69.9 atomic%, C: 22.7 atomic%, and O: 7.4 atomic%. Furthermore, the reflectance-reducing layer contains a chromium-based material containing chromium (Cr), oxygen (O), nitrogen (N), and carbon (C). The average content of each element is Cr: 48.5 atomic%, and O: 47.4 atomic%. , N: 3.7 atomic%, C: 0.4 atomic%. In addition, between the phase shift layer and the metal layer, and between the metal layer and the reflectance reduction layer, there is a composition gradient region in which each element is continuously reduced or increased. The bonding state (chemical state) of the element was evaluated from the spectrum of Cr, O, and N of each layer. As a result, it was confirmed that the phase shift layer mainly contains chromium mononitride (CrN), and further, chromium (III) oxide (Cr ₂ O ₃ ). It was also confirmed that the bonding state (chemical state) of the elements constituting the metal layer mainly contains chromium (Cr), and further, chromium (III) oxide (Cr ₂ O ₃ ). It was also confirmed that the bonding state (chemical state) of the elements constituting the reflectance-reducing layer mainly contains chromium (III) oxide (Cr ₂ O ₃ ), There is CrN and CrN ₂ N). The phase shift film has a transmittance of 4.9% to 365 nm light and a phase difference of 187 ° through the above three-layer structure. The transmittance and phase difference were measured using MPM-100 (trade name) manufactured by Lasertec. The measurement was performed in the same manner in Examples 2, 3, and Comparative Example 1. Curve a in FIG. 3 shows the film surface reflectance spectrum of the phase-shifting film of the phase-shifting mask substrate of Example 1. Curve a in FIG. 4 represents the back surface reflectance spectrum of the phase-shifting film of the phase-shifting mask substrate of Example 1. As can be seen from Fig. 3, regarding the phase-shifting film, the film surface reflectance is 13.3% at a wavelength of 313 nm, 9.6% at 350 nm, 8.3% at a wavelength of 365 nm, and a wavelength of 405 nm. It is 7.1% at a wavelength of 413 nm, 7.3%, and 8.1% at a wavelength of 436 nm. Regarding the phase shift film, the variation of the reflectance of the film surface is 2.5% in the wavelength region of 350 nm to 436 nm, 1.2% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 6.2%. As can be seen from Fig. 4, regarding the phase shift film, the back surface reflectance is 9.7% at a wavelength of 313 nm, 8.8% at 350 nm, 9.0% at a wavelength of 365 nm, and a wavelength of 405 nm. Is 12.3%, 13.2% at a wavelength of 413 nm, and 16.1% at a wavelength of 436 nm. Regarding the phase shift film, the variation of the reflectance of the film surface is 7.3% in the wavelength region of 350 nm to 436 nm, 7.1% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 7.3%. In addition, the film surface reflectance and the back surface reflectance were measured using SolidSpec-3700 (trade name) manufactured by Shimadzu Corporation. The measurement was performed in the same manner in Examples 2, 3, and Comparative Example 1. Using the above-mentioned phase shift mask substrate, a phase shift mask is manufactured by the following method. First, a resist film containing a novolac positive photoresist is formed on the phase shift film of the phase shift mask substrate. Thereafter, a laser plotter was used to draw a specific pattern on the resist film using laser light having a wavelength of 413 nm. Thereafter, the resist film is developed using a specific developing solution to form a resist film pattern on the phase shift film. Thereafter, the phase shift film is etched by using the resist film pattern as a photomask to form a phase shift film pattern. Each of the phase shift layer, the metal layer, and the reflectance reducing layer constituting the phase shift film is formed of a chromium-based material containing chromium (Cr). Therefore, the phase shift layer, the metal layer, and the reflectance reducing layer can be etched by the same etching solution. Here, as an etching solution for etching the phase shift film, an etching solution containing ceric ammonium nitrate and perchloric acid was used. Thereafter, the resist film pattern was peeled using a resist stripping solution. The phase shift film pattern cross section of the phase shift mask manufactured using the above phase shift mask substrate has suffered some erosion in the metal layer located at the center portion of the film thickness direction of the phase shift film pattern, but it does not affect the mask characteristics The extent of the impact. The phase shift film pattern cross section of the phase shift mask was observed using an electron microscope (JSM7401F (trade name) manufactured by Japan Electronics Co., Ltd.). The measurement was performed in the same manner in Examples 2, 3, and Comparative Example 1. The CD of the phase-shifting film pattern of the phase-shifting mask manufactured by using the above-mentioned phase-shifting mask substrate is not all 70 nm, which is good. The CD unevenness is the deviation width between the target line and the gap pattern (the width of the line pattern: 2.0 μm, the width of the gap pattern: 2.0 μm). The CD unevenness of the phase shift film pattern of the phase shift mask was measured using SIR8000 manufactured by Seiko Instruments Technology. The measurement was performed in the same manner in Example 2 and Comparative Example 1. Because the phase shift mask has excellent pattern cross-sectional shape and excellent CD uniformity, and the film surface reflectance of the phase shift film pattern of the exposed light is low, the use of the above phase shift mask can produce high resolution High-definition display device. Embodiment 2. The phase-shifting film in the phase-shifting mask base of Embodiment 2 includes a phase-shifting layer, a metal layer, and a reflectance reducing layer which are sequentially arranged from the transparent substrate side (see FIG. 6). A phase-shifting mask substrate was manufactured in the same manner as in Example 1 except that the reflectance-reducing layer of the phase-shifting mask substrate of Example 2 was formed under the following film-forming conditions. Regarding the reflectance reducing layer, a sputtering power of 2.15 kW was applied to the chromium target, and Ar gas, N ₂ Gas and O ₂ The mixed gas of the gas is introduced into the sputtering chamber, and the transparent substrate is conveyed at a speed of 200 mm / min. When the transparent substrate passes near the chromium target, a reflection-reducing layer including CrON is formed on the metal layer. Here, the mixed gas system uses Ar as 35 sccm, N ₂ Becomes 35 sccm, O ₂ A flow rate of 22 sccm was introduced into the sputtering chamber. Regarding the phase shift film of Example 2, the results of measuring the composition in the depth direction by X-ray photoelectron spectroscopy (ESCA) are shown in FIG. 6. The phase shift layer contains a chromium-based material containing chromium (Cr), oxygen (O), nitrogen (N), and carbon (C). The average content of each element is Cr: 50.6 atomic%, O: 39.5 atomic%, and N: 8.3 atomic%, C: 1.6 atomic%. The metal layer contains a chromium-based material containing chromium (Cr), carbon (C), and oxygen (O), and the average content of each element is Cr: 69.2 atomic%, C: 22.8 atomic%, and O: 8.0 atomic%. Furthermore, the reflectance-reducing layer 33 contains a chromium-based material containing chromium (Cr), oxygen (O), and nitrogen (N). The average content of each element is Cr: 46.6 atomic%, O: 51.5 atomic%, and N: 1.7. Atomic%, C: 0.2 atomic%. In addition, between the phase shift layer and the metal layer, and between the metal layer and the reflectance reduction layer, there is a composition gradient region in which each element is continuously reduced or increased. In addition, the bonding state (chemical state) of the element was evaluated from the spectrum of Cr, O, and N of each layer of the phase shift layer, the metal layer, and the reflectance reducing layer. As a result, the bonding state (chemical state) and implementation Example 1 is the same. As can be seen from FIGS. 5 and 6, the reflectance-reducing layer of Example 2 has an oxygen (O) content increase of 4.1 atomic% compared to the reflectance-reducing layer of Example 1. On the other hand, chromium (Cr ) Content decreased by 1.9 atomic%. As described above, since the content of oxygen (O) is higher than that of the reflectance-reducing layer of Example 1, the phase-shifting film of Example 2 is more excellent in terms of adhesion with the resist film. The phase shift film has a transmittance of 5.2% to 365 nm light and a phase difference of 183 ° through the above three-layer structure. The curve b in FIG. 3 shows the film surface reflectance spectrum of the phase-shifting film of the phase-shifting mask substrate of Example 2. Curve b in FIG. 4 shows the back surface reflectance spectrum of the phase shift film of the phase shift mask substrate of Example 2. As can be seen from Fig. 3, regarding the phase-shifting film, the film surface reflectance is 8.8% at a wavelength of 313 nm, 7.5% at 350 nm, 8.1% at a wavelength of 365 nm, and a wavelength of 405 nm. It is 10.6%, 11.1% at a wavelength of 413 nm, and 12.4% at a wavelength of 436 nm. Regarding the phase shift film, the variation range of the reflectance of the film surface was 4.8% in the wavelength region of 350 nm to 436 nm, and 4.3% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 4.9%. As can be seen from Fig. 4, regarding the phase shift film, the back surface reflectance is 8.7% at a wavelength of 313 nm, 8.9% at 350 nm, 10.1% at a wavelength of 365 nm, and a wavelength of 405 nm. Is 15.0%, 16.0% at a wavelength of 413 nm, and 18.1% at a wavelength of 436 nm. Regarding the phase shift film, the variation range of the reflectance of the film surface is 9.2% in the wavelength region of 350 nm to 436 nm, and 8.0% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm In the wavelength region, it is 9.7%. Thus, the phase shift film of Example 1 is more excellent from the viewpoint of the film surface reflectance. Using the phase shift mask substrate described above, a phase shift mask was manufactured in the same manner as in Example 1. The phase shift film pattern section of the phase shift mask manufactured by using the above phase shift mask substrate is vertical, and no erosion occurs in the metal layer. The CD of the phase-shifting film pattern of the phase-shifting mask manufactured using the above-mentioned phase-shifting mask substrate is not all 60 nm, which is good. In this way, the CD unevenness of the phase shift film pattern of Example 1 and Example 2 formed using the resist film pattern as a photomask is compared, and the CD unevenness of Example 2 is less, so it is the same as that of the resist film. From the viewpoint of adhesion, the phase shift film of Example 2 is considered to be more excellent. Because the phase shift mask has excellent pattern cross-sectional shape and excellent CD uniformity, and the film surface reflectance of the phase shift film pattern of the exposed light is low, the use of the above phase shift mask can produce high resolution High-definition display device. Embodiment 3 The phase-shifting film in the phase-shifting mask base of Embodiment 3 includes a phase-shifting layer, a metal layer, and a reflectance reducing layer sequentially arranged from the transparent substrate side (see FIG. 7). Each of the phase shift layer, the metal layer, and the reflectance reduction layer in the phase shift mask substrate of Example 3 was formed under the following film formation conditions. Regarding the phase shift layer, as a mixed gas, Ar is 35 sccm, N ₂ Becomes 35 sccm, CO ₂ Becomes 100 sccm, O ₂ A phase shift layer containing a chromium-based material (CrON) containing Cr, O, and N was formed on a transparent substrate in the same manner as in Example 1 except that the flow rate was set to 35 sccm. Next, as for the metal layer, a sputtering power of 0.5 kW was applied to a chromium target disposed in a sputtering chamber. A chromium-containing material containing Cr and C was formed on the phase shift layer in the same manner as in Example 1 ( CrC). Next, regarding the reflectance-reducing layer, as the mixed gas, Ar is 35 sccm, N ₂ Becomes 35 sccm, CO ₂ Becomes 100 sccm, O ₂ A reflectance-reducing layer containing a chromium-based material (CrCO) containing Cr, O, and N was formed on the metal layer in the same manner as in Example 1 except that it was introduced into the sputtering chamber at a flow rate of 35 sccm. Regarding the phase shift film of Example 3, the results of measuring the composition in the depth direction by X-ray photoelectron spectroscopy (ESCA) are shown in FIG. 7. The phase shift layer contains a chromium-based material containing chromium (Cr), oxygen (O), nitrogen (N), and carbon (C). The average content of each element is Cr: 45.5 atomic%, O: 53.8 atomic%, and N: 0.6 atomic%, C: 0.1 atomic%. The metal layer contains a chromium-based material containing chromium (Cr), carbon (C), and oxygen (O). The average content of each element is Cr: 74.7 atomic%, C: 15.8 atomic%, and O: 8.8 atomic%. N: 0.7 atomic%. Further, the reflectance-reducing layer 33 contains a chromium-based material containing chromium (Cr), oxygen (O), nitrogen (N), and carbon (C), and the average content of each element is Cr: 44.4 atomic% and O: 55.0 atoms %, N: 0.5 atomic%, C: 0.1 atomic%. In addition, between the phase shift layer and the metal layer, and between the metal layer and the reflectance reduction layer, there is a composition gradient region in which each element is continuously reduced or increased. The bonding state (chemical state) of the element was evaluated from the spectrum of Cr, O, and N of each layer. As a result, it was confirmed that the phase shift layer mainly contains dichromium nitride (Cr ₂ N), and further, chromium (III) oxide (Cr ₂ O ₃ ) And chromium (Ⅵ) (CrO ₃ ). It was also confirmed that the bonding state (chemical state) of the elements constituting the metal layer mainly contains chromium (Cr), and further, chromium (III) oxide (Cr ₂ O ₃ ). It was also confirmed that the bonding state (chemical state) of the elements constituting the reflectance-reducing layer mainly contains chromium (III) oxide (Cr ₂ O ₃ ). The phase shift film has a transmittance of 4.9% to 365 nm light and a phase difference of 187 ° through the above three-layer structure. Curve c in FIG. 3 shows the film surface reflectance spectrum of the phase shift film of the phase shift mask substrate of Example 3. Curve c in FIG. 4 represents the back surface reflectance spectrum of the phase-shifting film of the phase-shifting mask substrate of Example 3. As can be seen from Fig. 3, regarding the phase shift film, the film surface reflectance is 21% at a wavelength of 313 nm, 14.7% at 350 nm, 12.8% at a wavelength of 365 nm, and a wavelength of 405 nm. It is 10.2%, 9.8% at a wavelength of 413 nm, and 9.0% at a wavelength of 436 nm. Regarding the phase shift film, the variation range of the reflectance of the film surface was 5.7% in the wavelength region of 350 nm to 436 nm, and 3.8% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 12.0%. As can be seen from Figure 4, regarding the phase-shifting film, the back surface reflectance is 7.5% at a wavelength of 313 nm, 8.3% at 350 nm, 9.8% at a wavelength of 365 nm, and a wavelength of 405 nm. Is 14.9%, 15.9% at a wavelength of 413 nm, and 18.2% at a wavelength of 436 nm. Regarding the phase-shifting film, the variation range of the reflectance of the film surface was 9.9% in a wavelength region of 350 nm to 436 nm, and 8.3% in a wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 11.0%. In addition, the film surface reflectance and the back surface reflectance were measured using SolidSpec-3700 (trade name) manufactured by Shimadzu Corporation. The phase shift mask was manufactured using the phase shift mask substrate of Example 3 in the same manner as in the above embodiment. The phase shift film patterns of the obtained phase shift reticle have a CD of 65 nm, which is good. The CD unevenness is the deviation width between the target line and the gap pattern (the width of the line pattern: 2.0 μm, the width of the gap pattern: 2.0 μm). Because the phase shift mask has excellent pattern cross-sectional shape and excellent CD uniformity, and the film surface reflectance of the phase shift film pattern of the exposed light is low, the use of the above phase shift mask can produce high resolution High-definition display device. Comparative Example 1. The phase shift film in the phase shift mask substrate of Comparative Example 1 contained only a phase shift layer (CrOCN, film thickness 122 nm). The phase shift mask substrate of Comparative Example 1 is different from the phase shift mask substrate of the above-mentioned embodiment in that the phase shift film does not include a metal layer and a reflectance reduction layer. The phase shift layer in the phase shift mask substrate of Comparative Example 1 was formed under the following film formation conditions. Regarding the phase shift layer, a sputtering power of 3.5 kW was applied to a chromium target disposed in a sputtering chamber, and Ar gas, N ₂ Gas and CO ₂ The mixed gas of the gas is introduced into the sputtering chamber, and the transparent substrate is conveyed at a speed of 200 mm / min. When the transparent substrate passes near the chromium target, a phase shift layer including CrOCN with a film thickness of 122 nm is formed on the main surface of the transparent substrate. Here, the mixed gas system is 46 sccm, N with Ar ₂ Becomes 32 sccm, CO ₂ A flow rate of 18.5 sccm was introduced into the sputtering chamber. Regarding the phase shift film of Comparative Example 1, the composition in the depth direction was measured by X-ray photoelectron spectroscopy (ESCA). The phase shift film is uniform in the depth direction, Cr: 44 atomic%, C: 8 atomic%, O: 30 atomic%, and N: 18 atomic%. The phase shift film has a transmittance of 4.5% to 365 nm light and a phase difference of 181 ° by the above-mentioned one-layer structure. The curve d in FIG. 3 represents the film surface reflectance spectrum of the phase shift film of the phase shift mask substrate of Comparative Example 1. The curve d in FIG. 4 represents the back surface reflectance spectrum of the phase shift film of the phase shift mask substrate of Comparative Example 1. As can be seen from Fig. 3, regarding the phase shift film, the film surface reflectance is 21.0% at a wavelength of 313 nm, 23.9% at 350 nm, 24.0% at a wavelength of 365 nm, and a wavelength of 405 nm. 25.1%, 25.3% at a wavelength of 413 nm, and 26.0% at a wavelength of 436 nm. Regarding the phase-shifting film, the variation range of the film surface reflectance is 2.1% in the wavelength region of 350 nm to 436 nm, 2.0% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 12.0%. As can be seen from Figure 4, regarding the phase-shifting film, the back surface reflectance is 7.5% at a wavelength of 313 nm, 17.1% at 350 nm, 17.9% at a wavelength of 365 nm, and a wavelength of 405 nm. Is 19.9%, 20.2% at a wavelength of 413 nm, and 20.3% at a wavelength of 436 nm. Regarding the phase shift film, the variation of the reflectance of the film surface was 3.2% in the wavelength region of 350 nm to 436 nm, 2.4% in the wavelength region of 365 nm to 436 nm, and 313 nm to 436 nm. In the wavelength region, it is 11.0%. Using the above-mentioned phase shift mask substrate, a phase shift mask was manufactured in the same manner as in Example 1. The phase shift film pattern section of the phase shift mask manufactured by using the above phase shift mask substrate is vertical. The CD of the phase-shifting film pattern of the phase-shifting mask manufactured using the above-mentioned phase-shifting mask substrate is not all 90 nm, which does not reach the level required for manufacturing a phase-shifting mask for a high-resolution, high-definition display device. Although the above phase shift mask has an excellent pattern cross-sectional shape, the CD unevenness is large, and the film surface reflectance of the phase shift film pattern of the exposed light is high. Therefore, using the above phase shift mask cannot produce a high Resolution, high-definition display device. As mentioned above, although this invention was demonstrated in detail based on embodiment and an Example, this invention is not limited to this. Obviously, as long as it is a person with ordinary knowledge in the art, modifications or improvements within the technical idea of the present invention can be made. For example, in the embodiment, a reflectance reduction layer is provided as the first functional layer and a phase shift layer is provided as the second functional layer. However, when a specific optical characteristic is satisfied, a phase shift layer may be provided as the first functional layer. And has a reflectance-reducing layer as a second functional layer.

10‧‧‧Phase shift mask substrate

20‧‧‧ transparent substrate

30‧‧‧ phase shift film

31‧‧‧Phase shift layer

32‧‧‧Reflectivity reduction layer

33‧‧‧metal layer

40‧‧‧Light-shielding film pattern

FIG. 1 is a schematic diagram showing a film configuration of a base of a phase shift mask. Fig. 2 is a schematic view showing the structure of another film of a phase shift mask base. FIG. 3 is a film surface reflectance spectrum of a phase shift film of a phase shift mask substrate in Examples 1, 2, 3 and Comparative Example 1. FIG. FIG. 4 is a backside reflectance spectrum of the phase shift film of the phase shift mask substrate in Examples 1, 2, 3 and Comparative Example 1. FIG. FIG. 5 is a graph showing a composition analysis result of a depth direction of a phase shift film of a phase shift mask substrate in Example 1. FIG. FIG. 6 is a graph showing the results of analyzing the composition in the depth direction of the phase shift film of the phase shift mask substrate in Example 2. FIG. FIG. 7 is a graph showing the results of analyzing the composition in the depth direction of the phase shift film of the phase shift mask substrate in Example 3. FIG.

Claims (10)

A phase shift mask substrate, characterized in that it is provided on a transparent substrate with a phase shift film containing a chrome-based material, and the phase shift film has a first functional layer constituting a lower layer and a second function constituting an upper layer thereof. Layer and an intermediate layer disposed between the first functional layer and the second functional layer, the first functional layer and the second functional layer include a chromium-based material containing chromium, oxygen, and nitrogen, and the chromium is 30 to 70 Atomic%, oxygen is 20 to 60 atomic%, nitrogen is 0.4 to 30 atomic%, the content rate of nitrogen contained in the first functional layer is the same as or more than the content rate of nitrogen contained in the second functional layer The content rate of oxygen contained in the second functional layer is greater than the content rate of oxygen contained in the first functional layer. The intermediate layer contains chromium and carbon. The content of chromium is 55 to 90 atomic%. Carbon The content ratio is 10 to 45 atomic%, and the content ratio of chromium contained in the intermediate layer is higher than the content ratio of chromium contained in the first functional layer and the second functional layer. For example, the phase shift mask substrate of claim 1, wherein the first functional layer has a function of mainly adjusting the transmittance and phase difference of the light to be exposed, and the second functional layer has a function of reducing light incident on the phase shift film side. The function of the reflectance is that the film thickness of the first functional layer is thicker than the film thickness of the second functional layer. For example, the phase shift mask substrate of claim 1 or 2, wherein the first functional layer includes chromium nitride or dichromium nitride, and the second functional layer includes chromium (III) oxide formed by bonding chromium and oxygen. For example, the phase shift mask substrate of claim 1 or 2, wherein the intermediate layer further includes a chromium-based material containing oxygen, and the first functional layer, the intermediate layer, and the second functional layer include chromium (III) oxide. For example, the phase shift mask substrate of claim 1 or 2, wherein the film surface reflectance of the phase shift film to light incident from the phase shift film side is 15% or less in a wavelength region of 350 to 436 nm. For example, the phase shift mask substrate of claim 1 or 2, wherein the back surface reflectance of the phase shift film to light incident from the transparent substrate side is 22.5% or less in a wavelength region of 313 to 436 nm. For example, the phase shift mask substrate of claim 1 or 2, wherein a light-shielding film pattern is provided between the transparent substrate and the phase shift film. A method for manufacturing a phase-shifting photomask, which is characterized by having the following steps: on the above-mentioned phase-shifting film of the phase-shifting photomask substrate according to any one of claims 1 to 7, by using a layer having a wavelength selected from 350 nm to 436; a step of forming a resist film pattern by drawing processing and developing processing of laser light of any wavelength in a wavelength region of nm; and using the resist film pattern as a photomask and etching the phase shift film, The step of forming a phase shift film pattern on the transparent substrate. A method for manufacturing a display device, comprising the steps of: placing a phase shift mask manufactured by the method of manufacturing a phase shift mask according to claim 8 on a mask stage of an exposure device; The photomask irradiates the exposed light and transfers the phase shift film pattern to a resist film formed on a display device substrate. The method for manufacturing a display device according to claim 9, wherein the exposed light comprises a composite light of a plurality of wavelengths of light selected from a wavelength range of 313 nm to 436 nm.