TWI414882B - Half-tone phase shift blankmask, half-tone phase shift photomask, and manufacturing methods of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a halftone phase inversion blank mask, a halftone phase inversion photomask, and a method for manufacturing the same. <P>SOLUTION: In the halftone phase inversion blank mask, a transparent substrate, a phase inversion film, a metal film, and a resist film are layered sequentially. The phase inversion film has a constituent variable section where a composition ratio of at least one element among elements constituting the film is varied continuously in the film depth direction. In this way, the phase inversion film has mutually different composition ratios in the thickness direction, and the halftone phase inversion blank mask having the phase inversion film, which has excellent adhesiveness, particle property, pin hole property, chemical resistance, exposure resistance, residual stress, and surface resistance, can be manufactured. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

Halftone phase shift blank mask, halftone phase shift mask and manufacturing method thereof

The present disclosure relates to a half-tone phase shift blank mask and a half-tone phase shift mask that can implement a high-density critical dimension (CD) in a semiconductor lithography process. (half-tone phase shift photomask), and its manufacturing method, and more specifically, halftone phase shift blank mask, halftone phase shift applicable to 248 nm KrF lithography and 193 nm ArF lithography Photomask and its method of manufacture.

Due to the high level of integration of semiconductor integrated circuits, lithography, which is the core technology of semiconductor manufacturing processes, is becoming more and more important. In lithography, the exposure light wavelength is advanced to shorter wavelengths in the order of 436 nm G-line, 365 nm i-line, 248 nm KrF, and 193 nm ArF. Increase the resolution of the semiconductor circuit pattern. The use of shorter wavelengths for exposure greatly contributes to increased resolution, but it also has a negative effect on depth of focus (DoF) and, accordingly, causes serious problems in the design of optical systems containing lenses. .

In order to improve the DoF and reduce the burden of design, a phase shift mask has emerged. A phase shift mask is fabricated by using a phase shift blank mask. Currently, in phase shift blank masks, in particular, halftone phase shift blank masks have been widely used.

Forming a phase shift that simultaneously and substantially comprises molybdenum and tantalum on a 6025 substrate based on 6025 synthetic quartz glass having a size of substantially 152 mm Membrane, while manufacturing prior art halftone phase shift blank masks. At this time, the characteristics of the phase shift film such as composition ratio, density, and crystal state are substantially uniform in the thickness direction thereof. However, such phase shifting films having uniform characteristics in the thickness direction cause various problems in the blank mask process, the mask process, and the semiconductor manufacturing process.

First, with regard to the blank mask process, the phase shift film is located between the substrate and the metal film. At this time, the adhesion of the phase shift film is important with respect to the substrate and the metal film. When the phase shift mask and the metal film pattern are formed to fabricate the photomask, if the adhesion of the phase shift film is weak, the phase shift film can be detached from the metal film pattern, which causes malfunction. Moreover, ultrasonic waves are used to remove particles during the manufacture of the reticle. Therefore, if the adhesion of the phase shifting film is weak and the possibility that the phase shifting film pattern may be detached increases, it is necessary to increase the adhesion of the phase shifting film.

Moreover, in the process of manufacturing the reticle, a rinsing process for removing particles is performed using a chemical such as sulfuric acid or ammonia water. At this time, if the phase shift film has a weak chemical resistance, the phase shift film may be damaged, and thus, the function of the phase shift film may be lost. Therefore, a phase shift film having a high chemical resistance is required, and in particular, high chemical resistance is required at the surface of the phase shift film. Moreover, haze problems may occur due to residual chemicals that are not completely removed during the rinsing process. Therefore, in the case of a phase shift film having uniform characteristics in the thickness direction, turbidity may easily occur, which results in shortening of the life of the reticle.

Moreover, when a stress is generated between the transparent substrate and the phase shift film, the adhesion therebetween is reduced when the reticle is manufactured, or is generated due to residual stress. The distortion of the case deteriorates the registration characteristics. Moreover, when fabricating a semiconductor component, a reticle is used to perform the lithography process, and in the lithography process, radiation exposure is typically applied from the substrate toward the phase shift film. At this time, the exposure resistance, that is, the phase shift film is resistant to exposure. However, in the case of a phase shift film having a single film whose characteristics are uniform in its thickness direction, the exposure resistance characteristics are not controlled, and thus are weak.

Further, when a photomask is formed using a phase shift blank mask, it is possible to perform a resist pattern forming process by using an electron beam. In this case, it is important to reduce the phenomenon of electron charging through the low sheet resistance. However, in the case of a phase shift film having a single film whose characteristics are uniform in its thickness direction, the electron beam exposure characteristics are low due to high sheet resistance, thereby lowering the critical dimension (CD) characteristics.

The present disclosure provides a halftone phase shift blank mask, a half phase shift mask, and a method of fabricating the halftone phase shift blank mask, which can be used for 248 nm KrF and 193 nm ArF lithography and can enhance such as phase Characteristics of adhesion, chemical resistance, exposure resistance, turbidity, crystal state of the film, composition ratio, residual stress, and sheet resistance of the film.

According to an exemplary embodiment, a halftone phase shift blank mask is provided, comprising a transparent substrate, a phase shift film, a metal film, and a photoresist film, wherein the phase shift film includes a variable composition region in which elements constituting the film are formed The composition ratio of at least one of the elements continuously changes in the depth direction of the film.

According to another exemplary embodiment, there is provided a half-tone phase shifting mask formed by patterning and etching a halftone phase shifting blank mask, the halftone phase shifting The blank mask includes a transparent substrate, a phase shift film, a metal film, and a photoresist film which are sequentially stacked, and the phase shift film includes a variable composition region in which a composition ratio of at least one of elements constituting the film is The film continuously changes in the depth direction.

According to another exemplary embodiment, there is provided a method of fabricating a halftone phase shifting blank mask by sequentially forming a phase shift film, a metal film, and a photoresist film on a transparent substrate, wherein the plasma is turned on Forming a phase shift film by gradually or continuously changing at least one of a plurality of conditions constituting the process conditions, and the phase shift film includes a variable composition region in which at least one of the elements constituting the film is formed The composition ratio continuously changes in the depth direction of the film.

Hereinafter, the exemplary embodiments will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of a halftone phase shifting blank mask 100 for a hard mask, in accordance with an illustrative embodiment.

Referring to FIG. 1, a halftone phase shift blank mask 100 according to an exemplary embodiment includes a transparent substrate 110, a phase shift film 120, a metal film 130, and a photoresist film 140. The phase shift film 120, the metal film 130, and the photoresist film 140 are sequentially formed on the transparent substrate 110.

The transparent substrate 110 is formed by performing a plurality of lapping and polishing processes with respect to the substrate substrate. The transparent substrate 110 may be formed of one of synthetic quartz, calcium fluoride CaF ₂ and F-doped quartz. The transparent substrate 110 may have a size of 6025 and may have a birefringence of 2 nm / 6.35 mm at a wavelength of 192 nm. At this time, the substrate substrate was cerium oxide (SiO ₂ ) having a purity of 99.9999%, which was manufactured by slicing and edge grinding using a synthetic quartz ingot, and had a size of 152 × 152 ± 0.2 mm. And a thickness of 6.3 mm or more.

The transparent substrate 110 is fabricated by performing a plurality of polishing processes and a plurality of polishing processes with respect to the substrate substrate. First, a plurality of polishing processes are performed with respect to a substrate substrate having a size of 152 × 152 ± 0.2 mm and a thickness of 6.3 mm or more. In the case of performing a single grinding process, the polishing process is performed under high pressure using polishing particles having a relatively large particle size in consideration of process efficiency. In this case, the target thickness reduction can be easily achieved; however, damage may occur which includes cracks generated in the thickness direction from the surface of the substrate substrate. Internal cracks generated in the substrate base material as defects can be found in subsequent processes. Moreover, due to the coarse particle size of the polished particles, the accuracy of the target thickness reduction cannot be correctly achieved. Therefore, the transparent substrate 110 according to the current exemplary embodiment can be fabricated by performing a plurality of polishing processes in order to reduce defects and achieve an accurate target thickness reduction with respect to the substrate substrate. The polishing particles used in the polishing process for the substrate substrate may be selected from one or a group consisting of lanthanum carbide (SiC), diamond (C), zirconia (ZrO ₂ ), and alumina (Al ₂ O ₃ ). Above, and applied to a plurality of polishing processes. Moreover, the polishing particles used in the polishing process may have a size of 4 to 20 μm. If the size of the polishing particles is less than 4 μm, the target thickness reduction can be accurately achieved; however, the processing time may be prolonged, thereby reducing the productivity. Moreover, if the size of the polishing particles is larger than 20 μm, it is not easy to achieve the target thickness reduction and the defect level is lowered.

Next, a plurality of polishing processes are performed with respect to the substrate substrate subjected to a plurality of polishing processes. The slurry for polishing contains cerium oxide (CeO ₂ ), colloidal cerium oxide (SiO ₂ ) polishing particles, and hydrogen peroxide (H ₂ O ₂ ), and uses nitric acid (HNO ₃ ) or hydroxide. Potassium (KOH) is used to control the pH of the slurry. The overall pH of the polishing slurry in the polishing process can be controlled in the range of 6 to 12. In particular, inorganic bases such as potassium hydroxide (KOH) offer the advantage of a synergy effect because inorganic bases have an etching effect on the substrate substrate. At the same time, the polishing particles physically remove the substrate substrate during the polishing process. At this time, if the polishing particles have a size of 5 μm or more, the target thickness reduction can be easily achieved; however, it may be difficult to ensure good surface roughness. Moreover, if the polishing particles have a size of 5 μm or less, the substrate substrate subjected to the polishing process may have a small thickness reduction. Therefore, it takes a long processing time, thereby reducing the processing efficiency. Therefore, in the polishing process, the polishing particles CeO ₂ may have a particle size in the range of 0.5 μm to 5 μm. Moreover, the particle size of the colloidal ceria particles used in the plurality of polishing processes may range from 20 μm to 200 μm. If the colloidal cerium oxide particles have a size of 20 μm or less, the polishing efficiency of the polishing process is lowered, and if the colloidal cerium oxide particles have a size of 200 μm or more, the polishing process may not be satisfied. Guaranteed surface roughness.

The polishing process improves surface roughness. Therefore, in the case where a plurality of polishing processes are performed, preferably, the size of the polishing particles gradually decreases as the frequency of the plurality of polishing processes increases. In the first polishing process, since the substrate substrate has a relatively rough surface state due to the polishing process, a larger amount of the substrate substrate must be removed than the second and third polishing processes. Thus, in In the first polishing process, a porous cerium pad having high hardness and low compressibility can be used as a polishing pad, and in the second polishing process, a cushion such as SUBA #400 to SUBA #800 can be used. . The polishing pad can be selected according to the amount of removal of the substrate substrate and the surface state. If a SUBA #400 or smaller polishing pad is used, the processing time is increased due to the relatively high compressibility and elastic recovery rate of the polishing pad and the low hardness characteristics, thereby reducing the polishing efficiency. If SUBA #800 or larger polishing pad is used, the target surface roughness may not be easily achieved due to the low compressibility and elastic recovery rate of the polishing pad and high hardness characteristics. The cushion used in the second polishing process may have a compressibility of 3% or more and an elastic recovery rate of 65% or more. In a polishing pad having a compressibility of 3% or more, when a polishing pressure is applied to the ceria particles, the nap layer around the particles is elastically deformed to distribute and absorb the polishing pressure, and accordingly, suppress The formation of defects having a concave shape that may occur on the surface of the substrate. In a polishing pad having an elastic recovery ratio of 65% or more, since the raised layer can be easily compressed and recovered, the raised layer does not allow the larger cerium oxide particles to remain in the raised layer, and therefore, the concave defect can be suppressed. produce. In the third polishing process, a suede pad as a super-soft pad is used as a polishing pad. Since the surface roughness and particle characteristics must be improved as much as possible in the third polishing process, an ultra-soft polishing pad having a low hardness and a relatively large elastic recovery rate and compressibility is used. The ultra-soft polishing pad used in the third polishing process may have a compressibility of 6% or more and an elastic recovery rate of 72% or more. Since the defect must be further strictly controlled in the third polishing process, the polishing pad has More compressibility and elastic recovery than the polishing pad used in the second polishing process.

Grooves included in the polishing pad used in the polishing process can have various shapes. For example, a polishing pad having a groove of 25 mm pitch, 4 mm width, and a depth of 0.5 mm can be used. The groove of the polishing pad increases the polishing efficiency of the transparent substrate 110 by supplying a sufficient amount of the slurry to the transparent substrate 110 during the polishing process. Polishing pads without grooves can also be used. The size of the groove can vary depending on the polishing process, and the use of the polishing pad having the groove can be determined according to the polishing process. Further, if the polishing pad used in the polishing process has a structure of two or more layers, the raised layer corresponding to the polishing pad of the second layer from the direct opposite direction may have a thickness in the range of 200 μm to 600 μm. If the raised layer has a thickness of 200 μm or less, the elastic recovery rate of the polishing pad is reduced, and therefore, it is difficult to ensure good surface roughness, and it will be a negative effect in view of the defects containing the particles. If the raised layer has a thickness of 600 μm or more, the polishing efficiency which ensures the surface roughness is lowered.

The phase shift film 120 shifts the phase of the exposure by 180°. The phase shift film 120 substantially contains molybdenum and rhenium, and may additionally contain at least one element selected from the group consisting of nitrogen, carbon, oxygen, and fluoride.

At least one of the elements constituting the phase shift film 120 has a region (hereinafter referred to as "variable composition region") in which the difference in content is equal to or greater than 3 at% in the thickness direction of the phase shift film 120. Moreover, in the phase shift film 120, the element content is different in the thickness direction thereof, and the thickness of the variable composition region can be selectively controlled. The elements with poor content may be molybdenum and niobium, and molybdenum or niobium The content may have a difference of 3 at% or more in the thickness direction of the phase shift film 120. When a region where the difference in content between molybdenum and niobium is at least 3 at% forms an interface with the remaining region, a thickness difference between molybdenum and niobium of at least 3 at% may be equal to or less than 50 Å. If the content of molybdenum or niobium having a difference of 3 at% or more in the thickness direction of the phase shift film 120 is greater than 50 Å, it is considered that the content of molybdenum or niobium has a thickness direction of the phase shift film 120. A zone of 3 at% or greater does not form an interface with the remaining zone.

The content of the elements constituting the phase shift film 120 may be uniform in the width direction of the phase shift film 120. At this time, the composition uniformity in the width direction of the phase shift film 120 may be equal to or less than 10%. The composition uniformity can be calculated using the following equation, and the measurement position can be at least 5 points in the width direction of the phase shift film 120. The composition of the film can be analyzed using the AES method, the XPS method, and the RBS method.

The phase shift film 120 may have a density difference in a range from 0.2 g/cm ³ to 2.0 g/cm ³ in its thickness direction. If the difference in density in the thickness direction of the phase shift film 120 is less than 0.2 g/cm ³ , the phase shift film 120 has a state similar to the state in which the density does not change, and if the density changes by more than 2.0 g/cm ³ , the phase shift film The stress in 120 can vary greatly. Moreover, the phase shift film 120 may have a residual stress difference in the thickness direction, and specifically, may include a region in which the residual stress difference in the thickness direction thereof is equal to or greater than 10 MPa.

When the phase shift film 120 is formed using a sputtering method, it is summarized in Table 1. Condition.

The phase shift film 120 is formed by sputtering a target of molybdenum molybdenum under the process conditions outlined in Table 1. The molybdenum content in the molybdenum molybdenum target is 5 to 30 at%, and the remainder is ruthenium. At this time, the sputtering target has a uniform element distribution in the thickness direction and the width direction, and specifically, the composition uniformity may be equal to or less than 10%. Further, the sputtering target is manufactured by a hot press (HP) method or a hot iso-static pressure (HIP) method, and may have a particle diameter of 30 μm or less. Moreover, the sputtering target may have a uniform particle size distribution in its thickness direction or width direction, and may have a particle size distribution error equal to or less than 10% in its thickness direction or width direction.

The metal film 130 is a multilayer film. When the metal film 130 has a two-layer structure, the lower layer positioned close to the substrate functions as a light shielding film and has a main component selected from one of the group consisting of Cr, CrN, CrCN, CrON, CrCON, and CrO, CrCO, or mixture. The upper layer positioned away from the substrate serves as an antireflection film and has a main component selected from one of the group consisting of Cr, CrN, CrCN, CrON, CrCON, CrO, and CrCO, or a mixture thereof. At this time, the anti-reflection film has 10% to 25% at the wavelength of exposure. Reflectivity and optical density of 2.5 or greater. Specifically, in the case of optical density, the metal film 130 alone can achieve an optical density equal to or greater than 2.5, or the combination of the metal film 130 and the phase shift film 120 can achieve an optical density equal to or greater than 2.5.

Moreover, the metal film 130 includes a region having a composition difference of 3 at% or more in the thickness direction thereof and having a thickness of 50 Å or less, and a region having a composition difference of 3 at% or more has a depth at the metal film 130. The composition that changes continuously in the direction.

At this time, forming a region in which the composition continuously changes in the depth direction of the metal film 130 means performing deposition of the metal film 130 in a state including process conditions for controlling the characteristics of the metal film 130 without turning off the power. At least one zone that changes continuously or stepwise in the state of the slurry. That is, the continuous change of the composition of the metal film 130 in the depth direction of the metal film 130 means that the process conditions are continuously or stepwise changed during the sputtering for forming the metal film.

Further, the metal film 130 may have a three-layer structure having a light shielding film, an antireflection film, and an etch stop film. In the three-layer structure of the metal film 130, a layer serving as a light shielding film and an anti-reflection film is formed of MoSi as a main component, and contains a group selected from the group consisting of MoSi, MoSiO, MoSiN, MoSiC, MoSiCN, MoSiCO, and MoSiCON. One, or a mixture thereof. The layer serving as the etching stopper film is formed of Cr as a main component, and contains one selected from the group consisting of Cr, CrN, CrCN, CrON, CrCON, CrO, and CrCO, or a mixture thereof. Further, in the metal layer 130 having a three-layer structure, the composition difference of the elements constituting the metal layer 130 has 50 Å or more in a region equal to or greater than 3 at% in the thickness direction thereof. A smaller thickness, and a region constituting a difference in composition of the elements of the metal layer 130 equal to or greater than 3 at% (which does not have an interface) is configured by a region constituting a continuous change in the thickness direction of the metal film 130. Moreover, the metal layer 130 may have a multilayer structure having an interface therein, or may have a region in which the composition generally changes in the thickness direction thereof as in the phase shift film 120.

Further, an etch stop film may be additionally included between the phase shift film 120 and the metal film 130.

The photoresist film 140 may be formed of a photoresist material containing a strong acid, and an organic thin film including a strong acid having a higher concentration than the photoresist film 140 may be formed under the photoresist film 140. The organic film positioned under the photoresist film 140 can be developed by a developer regardless of the application of the exposure process. The photoresist film 140 may have a thickness in the range of 1,000 Å to 4,500 Å. Moreover, an organic thin film having a thickness of 700 Å or less and containing a strong acid having a higher concentration than the photoresist film 140 may be formed under the photoresist film 140. At this time, the organic film positioned under the photoresist film 140 can be developed by the developer regardless of the application of the exposure process. The photoresist material coated on the surface of the metal film 130 is a chemically amplified resist.

2 is a flow chart illustrating a method of fabricating a blank mask for a halftone phase shift mask, in accordance with an illustrative embodiment.

Referring to FIG. 2, a phase shift film 120 is formed on a transparent substrate 110 having a size of 6025 using a sputtering target manufactured by using an HP or HIP method, and the phase shift film 120 has a Mo: Si in a long penetration sputtering apparatus. The composition ratio of =2:8 (i.e., Mo: Si = 20 at%: 80 at%) is as shown in Fig. 3. The process conditions for depositing the phase shifting film 120 are summarized in Table 2.

The first deposition process was performed with respect to the phase shift film 120 for 30 seconds under the process conditions described in Table 2 (operation S200). At this time, the gas flow rate is not limited to 3~5 sccm, but based on the volume percentage (vol%), the flow rate of the Ar gas may be in the range of 10% to 70%, and the flow rate of the N ₂ gas may be in the range of 20% to 85%. . The pressure can also be in the range of 0.01 to 0.4 Pa, and the sputtering power can be in the range of 0.6 to 13 W/mm. Next, the second deposition process is continuously performed (operation S210). Moreover, in this case, the process conditions can be changed to control the characteristics of the phase shift film 120.

Through the process described above, a single-layer phase shift film 120 having two characteristics in the thickness direction can be formed. At this time, when the deposition conditions are changed from the lower layer to the upper layer of the phase shift film 120 to form the phase shift film 120 having no interface between the lower layer and the upper layer on the transparent substrate 110, the flow rate of the Ar gas is maintained at 3 sccm. And the flow rate of N ₂ gas gradually increases from 5→9→13→17 sccm. The sputtering power is also gradually increased from 0.7→1.0→1.2→1.5 kW. According to Auger analysis, the lower layer of phase shift film 120 contains 15 at% Mo, 40 at% Si, and 45 at% N, and the upper layer contains 11 at% Mo, 35 at% Si, and 54 at% N. As described above, since the upper layer of the phase shift film 120 contains a relatively large amount of nitrogen, the phase shift film 120 can have chemical durability, turbidity, adhesion to a metal film, residual stress, and amorphous state. Achieve excellent characteristics. Meanwhile, since the lower layer of the phase shift film 120 contains a relatively small amount of nitrogen, the following layers are excellent in exposure durability, adhesion to the substrate, and sheet resistance, and specifically, in pin holes and particles. The aspect is excellent. Moreover, the absence of an interface in the phase shift film 120 by achieving a multilayer continuous film enhances the characteristics associated with pinholes and particles. At the same time, it is also possible to fabricate the phase shifting film 120 having an interface by applying a mechanical shutter.

Next, the metal film 130 is formed on the phase shift film 120 via a sputtering process (operation S220). At this time, the metal film 130 may include at least two films. Next, an organic film containing a strong acid and having a thickness of 100 Å is formed on the metal film 130 by using a spin coating (operation S230). The organic film can be developed by controlling the soft baking conditions using a developer without requiring an exposure process. Moreover, if the organic film is not developed through the development process after the exposure process by controlling the soft baking conditions, the organic film can be removed only by a dry etching process. Next, a final photoresist film is formed on the organic film by coating a positive type chemically amplified photoresist material (operation S240). Through the process described above, a halftone phase shifting blank mask having a continuous multilayer structure can be fabricated. Thereafter, a half-phase shift mask can be formed by patterning and etching a halftone phase shifting blank mask.

According to the halftone phase shift blank mask, the half phase shift mask and the manufacturing method thereof according to the present invention, since the phase shift film has different composition ratios in the thickness direction thereof, various kinds can be achieved according to the position in the phase shift film. Features. therefore, It is possible to manufacture a halftone phase shift blank mask which is excellent in adhesion, particle, chemical durability, exposure durability, residual stress, and sheet resistance characteristics of the phase shift film. Therefore, a high-quality half-phase shift mask can be manufactured, and finally, it allows fabrication of high-quality semiconductor elements.

Although the halftone phase shift blank mask, the half phase shift mask, and the method of fabricating the same have been described with reference to the specific embodiments, it is not limited thereto. It will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the invention as defined by the appended claims.

100‧‧‧ halftone phase shift blank mask

110‧‧‧Transparent substrate

120‧‧‧ phase shift film

130‧‧‧Metal film

140‧‧‧Photoresist film

S200~S240‧‧‧ operation

The exemplary embodiments may be understood in more detail in the following description of the accompanying drawings in which: FIG. 1 is a cross-sectional view of a blank mask for a hard mask in accordance with an illustrative embodiment.

2 is a flow chart illustrating a method of fabricating a blank mask for a hard mask, in accordance with an illustrative embodiment.

3 is a schematic diagram of a composition ratio of a phase shifting film in a long through sputtering apparatus for fabricating a blank mask for a hard mask, according to an exemplary embodiment.

S200~S240‧‧‧ operation

Claims (25)

A halftone phase shifting blank mask comprising a transparent substrate, a phase shifting film, a metal film and a photoresist film, wherein the phase shifting film comprises a variable composition region, wherein at least one of the elements constituting the film The composition ratio is continuously changed in the depth direction of the film, and at least one element constituting the film has a content equal to or greater than 3 at% in the thickness direction of the film in the variable composition region. difference. The halftone phase shifting blank mask of claim 1, wherein the phase shifting film substantially comprises molybdenum and niobium, and at least one of the molybdenum and the niobium is in the variable composition The region has a content difference equal to or greater than 3 at% in the thickness direction thereof. The halftone phase shifting blank mask of claim 1, wherein the phase shifting film substantially comprises molybdenum and tantalum, and at least one of the molybdenum and the tantalum is in the variable composition region There is a content difference equal to or greater than 3 at% in the thickness direction thereof, and the variable composition region has a thickness of less than or equal to 50 Å. The halftone phase shifting blank mask of claim 1, wherein the phase shifting film substantially comprises molybdenum and niobium, and has a thickness of 0.2 g/cm ³ to 2.0 g/cm ³ in a thickness direction thereof. The difference in density in the range. The halftone phase shift blank mask of claim 1, wherein the composition constituting the phase shift film has a composition uniformity of 10% or less. The halftone phase shift blank cover as described in item 1 of the patent application scope A cover wherein the phase shift film has different residual stresses in its thickness direction. The halftone phase shift blank mask of claim 6, wherein the phase shift film comprises a region in which a residual stress difference in the thickness direction is equal to or greater than 10 MPa. The halftone phase shift blank mask of claim 1, wherein the metal film comprises a multilayer structure comprising a lower layer and an upper layer, wherein the light shielding film serves as a light shielding film and is positioned adjacent to the transparent substrate. The lower layer includes one selected from the group consisting of Cr, CrN, CrCN, CrON, CrCON, CrO, and CrCO as a main component, or a mixture thereof, and functions as an antireflection film and is positioned away from the transparent substrate. The upper layer includes one selected from the group consisting of Cr, CrN, CrCN, CrON, CrCON, CrO, and CrCO as a main component, or a mixture thereof. The halftone phase shift blank mask of claim 8, wherein the multilayer metal film has a variable composition region having a thickness of 50 Å or less, and at least one of the elements constituting the film. The content of the element continuously changes in the depth direction of the multilayered metal film. The halftone phase shift blank mask of claim 1, wherein the metal film comprises a region in which a residual stress difference in a thickness direction thereof is equal to or greater than 10 MPa. The halftone phase shifting blank mask of claim 1, wherein the metal film has a three-layer structure, the three-layer structure comprising a first layer, a second layer, and a third layer, wherein the One layer and the second layer each include MoSi as a main component, and are selected from the group consisting of MoSi, MoSiO, MoSiN, MoSiC, MoSiCN, MoSiCO, and MoSiCON. One of the group, or a mixture thereof, and the third layer includes chromium as a main component, and one selected from the group consisting of Cr, CrN, CrCN, CrON, CrCON, CrO, and CrCO, or mixture. The semi-tone phase shifting blank mask of claim 11, wherein the three-layer metal film has a variable composition region having a thickness of 50 Å or less, and wherein the elements constituting the three-layer film are The content of at least one of the elements continuously changes in the depth direction of the multilayered metal film. The halftone phase shift blank mask of claim 1, wherein the photoresist film is formed of a photoresist material comprising a strong acid, and comprises an organic film having a strong acid higher than a concentration of the photoresist film. Formed under the photoresist film. The halftone phase shifting blank mask of claim 13, wherein the organic film formed under the photoresist film is developed by a developer. The halftone phase shift blank mask of claim 1, wherein the transparent substrate is formed by a plurality of polishing processes and a plurality of polishing processes. The halftone phase shift blank mask of claim 15, wherein the plurality of polishing processes are selected from the group consisting of tantalum carbide (SiC), diamond (C), zirconium oxide (ZrO ₂ ), and aluminum oxide ( The polishing particles of at least one of the group consisting of Al ₂ O ₃ ) are performed. The halftone phase shifting blank mask of claim 16, wherein the polishing particles have a particle size in the range of 4 μm to 20 μm. The halftone phase shift blank mask of claim 15, wherein the plurality of polishing processes include cerium oxide (CeO ₂ ), colloidal cerium oxide (SiO ₂ ), and hydrogen peroxide (H _{2 ).} The slurry of O ₂ ) is executed. A half-tone phase shifting mask manufactured by patterning and etching a halftone phase shifting blank mask as described in any one of claims 1 to 18. A method for manufacturing a halftone phase shifting blank mask by sequentially forming a phase shift film, a metal film, and a photoresist film on a transparent substrate, wherein the film is changed stepwise or continuously by turning on the plasma Forming the phase shift film at least one of a plurality of conditions constituting a process condition, and the phase shift film includes a variable composition region, wherein a composition ratio of at least one of elements constituting the film is The film is continuously changed in the depth direction, and at least one of the elements constituting the film has a content difference of equal to or more than 3 at% in the thickness direction of the film in the variable composition region. The method of manufacturing a halftone phase shifting blank mask according to claim 20, wherein the plurality of conditions constituting the process condition include a flow rate of a non-reactive gas, a flow rate of a reaction gas, a process pressure, and a sputtering The power, and the flow rate of the non-reactive gas is selected in the range of 10 to 70% by volume, and the flow rate of the reaction gas is selected in the range of 20 to 85% by volume, and the process pressure is It is selected in the range of 0.01 to 0.4 Pa, and the sputtering power is selected in the range of 0.6 to 13 W/mm. Manufacturing semi-phased phase as described in claim 20 or 21 A method of moving a blank mask, wherein the non-reactive gas is Ar gas, and the reaction gas is nitrogen. A method of fabricating a halftone phase shifting blank mask as described in claim 22, wherein the upper layer of the phase shifting film has a higher nitrogen content than the lower layer thereof. The method of manufacturing a halftone phase shifting blank mask according to claim 20, further comprising: forming the metal film on the phase shift film by using sputtering; and forming on the metal film Photoresist film. The method of manufacturing a halftone phase shifting blank mask according to claim 24, wherein the photoresist film is formed of a photoresist material including a strong acid, and includes a strong acid having a concentration higher than the photoresist film. An organic film is formed under the photoresist film.