Method for manufacturing phase shift mask and phase shift mask

Abstract

To provide a method for manufacturing a phase shift mask which dispenses with etching treatment for forming a light-shielding layer (light-shielding frame), and can simplify the whole manufacturing process, and a phase shift mask manufactured by the manufacturing method.SOLUTION: A phase shift mask 10 includes the steps of: forming a resist 3 having an opening on an exposure surface of a phase shift layer 2 formed on one surface of a substrate 1; etching a region exposed from the opening in the phase shift layer 2, by using the resist 3 as a mask; peeling the resist 3 from on the etched phase shift layer 2; coating a light-shielding resist 4 so as to coat the phase shift layer 2 from which the resist 3 has been peeled; and drawing and developing the light-shielding resist 4, and forming a light-shielding resist layer 4 having a pattern formed on the phase shift layer 2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a phase shift mask and a phase shift mask. [Background technology]

[0002] Some phase shift masks are provided with a light-shielding layer (light-shielding frame) to shield non-exposed areas on a wafer. A technology relating to a phase shift mask with a light-shielding layer is described in, for example, Patent Document 1. In the light-shielding layer according to the conventional technology, a chromium oxide (CrO) film is generally used, and an etching process is indispensable when processing a light-shielding layer formed of a CrO film. As described above, the conventional light-shielding layer (light-shielding frame) made of a CrO film requires an etching process in its manufacturing process, which tends to complicate the overall manufacturing process of the phase shift mask. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-72716 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made in light of the above circumstances, and aims to provide a method for manufacturing a phase shift mask that does not require an etching process to form a light-shielding layer (light-shielding frame), thereby simplifying the entire manufacturing process, and a phase shift mask manufactured by this manufacturing method. [Means for solving the problem]

[0005] The present invention has been made to solve the above-mentioned problems, and a method for manufacturing a phase shift mask according to one embodiment of the present invention is characterized by comprising the steps of: forming a resist pattern having openings on an exposed surface of a phase shift layer formed on one surface of a substrate; etching a region of the phase shift layer exposed from the openings using the resist pattern as a mask; peeling the resist pattern from above the etched phase shift layer; applying a light-shielding resist so as to cover the phase shift layer from which the resist pattern has been peeled off; and patterning and developing the light-shielding resist to form a light-shielding layer patterned on the phase shift layer.

[0006] A phase shift mask according to one aspect of the present invention includes a substrate, a phase shift layer patterned on one surface of the substrate, and a light-shielding layer formed on the phase shift layer; The light-shielding layer is characterized in that it is formed by laminating layers. In addition, a phase shift mask according to another aspect of the present invention is characterized in that it comprises a substrate, a phase shift layer patterned on one surface of the substrate, a light-shielding layer formed on the phase shift layer, and a light-shielding layer patterned on the other surface of the substrate. Effect of the Invention

[0007] According to the method for manufacturing a phase shift mask according to one aspect of the present invention, an etching process for forming a light-shielding layer (light-shielding frame) is not necessary, and the number of steps in the entire manufacturing process can be simplified. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic cross-sectional view illustrating a configuration of a phase shift mask according to an embodiment of the present disclosure. [Diagram 2] 5A to 5C are schematic cross-sectional views illustrating a manufacturing process of a phase shift mask according to an embodiment of the present disclosure. [Diagram 3] 1A to 1C are schematic cross-sectional views illustrating a manufacturing process (redoing a process) of a phase shift mask according to an embodiment of the present disclosure. [Figure 4] 1 is a schematic cross-sectional view showing a configuration of a phase shift mask according to a first modified example of an embodiment of the present disclosure. [Diagram 5] 5A to 5C are schematic cross-sectional views illustrating a manufacturing process of a phase shift mask according to a first modified example of an embodiment of the present disclosure. [Figure 6] 11 is a schematic cross-sectional view showing a configuration of a phase shift mask according to a second modified example of the embodiment of the present disclosure. FIG. [Figure 7] 10A to 10C are schematic cross-sectional views illustrating a manufacturing process of a phase shift mask according to a second modified example of an embodiment of the present disclosure. [Figure 8] FIG. 1 is a schematic cross-sectional view showing a configuration of a phase shift mask according to a conventional technique. [Figure 9] 1A to 1C are schematic cross-sectional views showing a manufacturing process of a phase shift mask according to the prior art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the structure of a phase shift mask and a method for manufacturing a phase shift mask according to an embodiment of the present disclosure will be described with reference to the drawings. Here, the configurations shown in the drawings are schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each layer, etc. are different from the actual ones. In addition, the embodiments shown below are examples of configurations for embodying the technical idea of ​​the present disclosure, and the technical idea of ​​the present disclosure is not limited to the materials, shapes, structures, etc. of the components described below. The technical idea of ​​the present disclosure can be modified in various ways within the technical scope defined by the claims described in the claims.

[0010] (Overall structure of phase shift mask) The configuration of a phase shift mask according to an embodiment of the present disclosure will be described below. Fig. 1 is a schematic cross-sectional view showing a configuration of a phase shift mask according to an embodiment of the present disclosure. The phase shift mask 10 shown in Fig. 1 is a phase shift mask (i.e., a patterned phase shift mask) to which exposure light having a wavelength of 200 nm or less is applied and which has a circuit pattern, and includes a substrate 1 transparent to the exposure wavelength, a phase shift layer 2 having a circuit pattern formed on the substrate 1, and a light-shielding resist layer 4 formed so as to cover the upper surface of the phase shift layer 2 located in a non-exposed region.

[0011] Each layer constituting phase shift mask 10 according to the embodiment of the present disclosure will now be described in detail. (substrate) There is no particular limitation on the substrate 1, and as the substrate 1, for example, quartz glass, CaF2, aluminosilicate glass, or the like is generally used.

[0012] (Phase shift layer) The phase shift layer 2 is formed on the substrate 1 with or without another film interposed therebetween. The phase shift layer 2 is, for example, a film that is resistant to oxygen-containing chlorine-based etching (Cl / O-based) and can be etched with fluorine-based etching (F-based). The transmittance value of the phase shift layer 2 is, for example, in the range of 3% to 80% with respect to the transmittance of the substrate 1, and the optimum transmittance can be appropriately selected according to the desired wafer pattern. The phase difference value of the phase shift layer 2 is, for example, in the range of 160 degrees to 220 degrees, and more preferably in the range of 175 degrees to 190 degrees. That is, the phase shift layer 2 may have a transmittance to the exposure light in the range of 3% to 80% and a phase difference in the range of 160 degrees to 220 degrees. When the transmittance of the phase shift layer 2 to the exposure light is less than 3%, good exposure performance may not be obtained. When the phase difference is in the range of 160 degrees to 220 degrees, the required exposure performance can be easily maintained.

[0013] In other words, the phase shift layer 2 is a layer that can adjust the phase and transmittance of the transmitted exposure light by a predetermined amount. Here, "adjusting the phase" means, for example, inverting the phase. Also, "transmittance" means the transmittance of the exposure light. The phase shift layer 2 is, for example, a single layer film containing silicon and at least one selected from a transition metal, nitrogen, oxygen, and carbon, or a multilayer film or gradient film thereof, and the transmittance and phase difference for the exposure wavelength are adjusted by appropriately selecting the composition and film thickness.

[0014] The phase shift layer 2 preferably contains silicon in the range of 20 atomic % to 60 atomic % inclusive, preferably contains transition metals in the range of 0 atomic % to 20 atomic % inclusive, preferably contains nitrogen in the range of 30 atomic % to 80 atomic % inclusive, preferably contains oxygen in the range of 0 atomic % to 30 atomic % inclusive, and preferably contains carbon in the range of 0 atomic % to 10 atomic % inclusive, based on the element ratio of the entire phase shift layer 2. More preferred content ranges of each element in the phase shift layer 2 are as follows: silicon in the range of 30 atomic % to 50 atomic % inclusive, transition metals in the range of 0 atomic % to 10 atomic % inclusive, nitrogen in the range of 40 atomic % to 70 atomic % inclusive, oxygen in the range of 0 atomic % to 20 atomic % inclusive, and carbon in the range of 0 atomic % to 5 atomic % inclusive, based on the element ratio of the entire phase shift layer 2. If the content of each element in the phase shift layer 2 is within the above numerical range, the phase difference as well as the transmittance of the phase shift layer 2 can be easily controlled. The phase shift layer 2 may contain at least one of oxide, carbide, and nitride of a metal silicide. In this case, the metal constituting the metal silicide may be the above-mentioned transition metal.

[0015] The transition metal contained in the phase shift layer 2 is preferably at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, and tungsten, and more preferably molybdenum. If the transition metal contained in the phase shift layer 2 is at least one selected from molybdenum, titanium, vanadium, cobalt, nickel, zirconium, niobium, tantalum, and tungsten, the phase shift layer 2 can be easily processed, and if the transition metal is molybdenum, the phase shift layer 2 can be more easily processed, such as by etching.

[0016] (light shielding layer) The light-shielding resist layer (light-shielding layer) 4 according to the embodiment of the present disclosure is a layer formed of a resist having light-shielding properties (hereinafter, also simply referred to as "light-shielding resist 4"). The light-shielding resist 4 is photosensitive to electron beams or light, and has substantially low transmittance with respect to the exposure wavelength of an exposure device when transferring the circuit pattern of the obtained photomask to a wafer, for example, ultraviolet light such as i-line (365 nm), KrF (248 nm), and ArF (193 nm). The light-shielding resist 4 according to the embodiment of the present disclosure is preferably one having a transmittance of almost zero, i.e., less than 1%, preferably less than 0.5%, and more preferably less than 0.1% for excimer laser light such as KrF (248 nm) and ArF (193 nm).

[0017] If the resist has low light transmittance with respect to the exposure wavelength used for pattern transfer onto the wafer, the area where the light-shielding resist layer 4 is formed becomes a light-shielding portion, enabling pattern transfer. The light-shielding resist 4 is not particularly limited as long as it has such characteristics, and either a positive type or a negative type can be used. Specific examples include novolak type resists such as compositions of novolak resin and quinone diazide, and compositions of novolak resin and polymethylpentene-1-sulfone, positive resists such as copolymers of α-methylstyrene and α-methylchloroacrylate, and chemically amplified resists obtained by compounding inhibitors and acid generators with novolak resins or phenolic resins, and negative resists such as crosslinked resists mainly composed of chloromethylated polystyrene, but are not limited to these.

[0018] (Method of manufacturing phase shift mask) A manufacturing method of a phase shift mask 10 according to an embodiment of the present disclosure includes the steps of forming a resist (patterned resist) 3 having openings on an exposed surface of a phase shift layer 2 formed on one side (front surface) of a substrate 1, etching an area of ​​the phase shift layer 2 exposed from the openings using the resist 3 as a mask, peeling the resist 3 from above the etched phase shift layer 2, applying a light-shielding resist 4 to cover the phase shift layer 2 from which the resist 3 has been peeled off, and patterning and developing the light-shielding resist 4 to form a patterned light-shielding resist layer 4 on the phase shift layer 2.

[0019] Each step of the method for producing phase shift mask 10 according to the embodiment of the present invention will now be described in detail. FIG. 2 is a schematic cross-sectional view showing a manufacturing process of the phase shift mask 10 shown in FIG. 1. FIG. 2(a) shows a process of laminating a phase shift layer 2 and a resist 3 in this order on one surface (front surface) of a substrate 1. FIG. 2(b) shows a process of forming a resist (patterned resist) 3 having an opening on an exposed surface of the phase shift layer 2 formed on one surface of the substrate 1. FIG. 2(c) shows a process of etching an area of ​​the phase shift layer 2 exposed from the opening using the patterned resist 3 as a mask. FIG. 2(d) shows a process of peeling off the patterned resist 3 from the etched phase shift layer 2. FIG. 2(e) shows a process of applying a light-shielding resist 4 so as to cover the phase shift layer 2 from which the patterned resist 3 has been peeled off. FIG. 2(f) shows a process of drawing and developing the light-shielding resist 4 to form a patterned light-shielding resist layer 4 on the phase shift layer 2. In this manner, the phase shift mask 10 according to the embodiment of the present disclosure is manufactured.

[0020] In the step of FIG. 2(a), the resist 3 may be made of either a positive resist or a negative resist, but it is preferable to use a chemically amplified resist for electron beam writing, which allows for the formation of a highly accurate pattern. The film thickness of the resist 3 is, for example, in the range of 50 nm to 250 nm. In particular, when producing a phase shift mask that requires the formation of a fine pattern, in order to prevent the pattern from collapsing, it is necessary to thin the resist 3 so that the aspect ratio of the patterned resist 3 does not become large, and a film thickness of 200 nm or less is preferable. On the other hand, the lower limit of the film thickness of the resist 3 is determined by comprehensively considering conditions such as the etching resistance of the resist material used, and is preferably 60 nm or more. When a chemically amplified resist for electron beam writing is used as the resist film, the energy density of the electron beam during writing is 35 μC / cm 2 to 100μC / cm 2 After this drawing, a heat treatment and a development treatment are performed to obtain a patterned resist 3 as shown in FIG. 2(b).

[0021] In the step of Fig. 2(c), the conditions of fluorine-based dry etching (F-based) for patterning the phase shift layer 2 may be known, and CF4, C2F6, or SF6 are generally used as the fluorine-based gas, and active gas such as oxygen or inert gas such as nitrogen gas or helium gas may be mixed as necessary. In the case of Fig. 2(c), the resist 3 is resistant to the fluorine-based dry etching (F-based), so it remains without being removed or patterned in this step. In Fig. 2(c), the substrate 1 is generally recessed by about 1 nm to 3 nm at the same time to prevent the phase shift layer 2 from being removed and to fine-tune the phase difference.

[0022] In the step of FIG. 2(d), the resist 3 may be removed by wet stripping using a stripping liquid, or by dry stripping using dry etching. In the step of FIG. 2(e), the light-shielding resist 4 is usually applied by spin coating, but scan coating may also be used. After application, a pre-bake step may be performed using a hot plate method, a hot air circulating oven method, or the like, if necessary. As will be described later, it is desirable to remove the light-shielding resist 4 that has adhered to the side, back and front edges of the substrate 1 during spin coating prior to the pre-bake step.

[0023] In the step of FIG. 2(f), the drawing and development of the light-shielding resist 4 can be performed by any method, such as a dipping method, a spray method, or a paddle method, using an alkaline aqueous solution, an organic solvent, or the like, depending on the type of light-shielding resist used. From the viewpoint of reducing the amount of foreign matter attached and the amount of liquid used, the spray method or the paddle method is preferable. If necessary, a post-baking process may be carried out to form the light-shielding resist layer 4. In this way, the method for manufacturing phase shift mask 10 according to the embodiment of the present disclosure does not require an etching process in the manufacturing process of the light-shielding layer because it does not use a CrO film as the light-shielding layer (light-shielding frame). Therefore, the entire manufacturing process can be simplified (the number of steps can be reduced) compared to the manufacturing method for a phase shift mask according to the conventional technology described below.

[0024] Next, a manufacturing process (redoing a process) of the phase shift mask 10 according to an embodiment of the present disclosure will be described. Fig. 3 is a schematic cross-sectional view showing a manufacturing process (redoing a process) of a phase shift mask according to an embodiment of the present disclosure. Note that the "redoing a process" according to an embodiment of the present disclosure may also be called re-forming or reworking. FIG. 3(a) shows a phase shift mask 10 according to an embodiment of the present disclosure. FIG. 3(b) shows a process of peeling off the light-shielding resist layer 4 formed on the phase shift layer 2 of the phase shift mask 10. FIG. 3(c) shows a process of applying the light-shielding resist 4 again so as to cover the phase shift layer 2 from which the light-shielding resist layer 4 has been peeled off. FIG. 3(d) shows a process of drawing and developing the light-shielding resist 4 to form again a light-shielding resist layer 4 patterned on the phase shift layer 2. In this way, a new phase shift mask 11 can be produced (manufactured) using the phase shift mask 10 according to an embodiment of the present disclosure.

[0025] In addition, the light-shielding resist layer 4 shown in Fig. 3(d) can also be peeled off again. Therefore, by peeling off the light-shielding resist layer 4 shown in Fig. 3(d), it is possible to return to the state shown in Fig. 3(b). In this way, the manufacturing process of the phase shift mask 10 according to the embodiment of the present disclosure allows for remanufacturing (reforming: reworking) of the light-shielding resist layer 4. This makes it easy to change the light-shielding area. In the embodiment of the present disclosure, the method for removing the light-shielding resist layer 4 may be, for example, so-called dry removal or chemical removal.

[0026] (Other embodiments) 2(a) , the exposed surface of the phase shift layer 2 may be subjected to a primer treatment before applying the resist 3. By applying the resist 3 after the exposed surface of the phase shift layer 2 is subjected to a primer treatment, the adhesion of the resist 3 can be improved. 2(e) of applying the light-shielding resist 4, the exposed surface of the phase shift layer 2 from which the resist 3 has been peeled off may be treated with a primer before applying the light-shielding resist 4. By applying the light-shielding resist 4 after treating the exposed surface of the phase shift layer 2 with a primer, the adhesion of the light-shielding resist 4 can be improved.

[0027] (Modifications of the embodiment of the present disclosure) Hereinafter, a first modified example and a second modified example of the embodiment of the present disclosure will be described. (First Modification) FIG. 4 is a schematic cross-sectional view showing a configuration of a phase shift mask 12 according to a first modification of the embodiment of the present disclosure. The phase shift mask 12 shown in FIG. 4 includes a substrate 1, a phase shift layer 2 patterned on one surface of the substrate 1, and a light-shielding resist layer 4 formed on the phase shift layer 2, and a part of the light-shielding resist layer 4 is laminated. More specifically, the phase shift mask 12 according to the first modification of the embodiment of the present disclosure includes a light-shielding resist layer 4a formed so as to cover the upper surface of the phase shift layer 2 located in the exposed region, and a light-shielding resist layer 4b formed so as to cover the upper surface of the phase shift layer 2 located in the non-exposed region. The layer thickness of the light-shielding resist layer 4b is thicker than the layer thickness of the light-shielding resist layer 4a. The layer thickness of the light-shielding resist layer 4b is, for example, in the range of 1.5 times to 2.5 times the layer thickness of the light-shielding resist layer 4a. Phase shift mask 12 having such a structure allows the thickness of the light-shielding resist layer to be adjusted appropriately, so that the degree of light-shielding in the light-shielding area can be easily adjusted.

[0028] A method for manufacturing phase shift mask 12 according to a first modified example of the embodiment of the present disclosure will now be described. 5A to 5C are schematic cross-sectional views illustrating a manufacturing process of a phase shift mask according to a first modified example of the embodiment of the present disclosure. Fig. 5(a) shows a phase shift mask 10 according to an embodiment of the present disclosure. Fig. 5(b) shows a process of applying light-shielding resist 4 again so as to cover phase shift layer 2 provided in phase shift mask 10. Fig. 5(c) shows a process of drawing and developing the newly applied light-shielding resist 4 to form a light-shielding resist layer 4 patterned on phase shift layer 2 again. In this manner, a phase shift mask 12 according to a first modified embodiment of the present disclosure is manufactured.

[0029] (Second Modification) Fig. 6 is a schematic cross-sectional view showing a configuration of a phase shift mask 13 according to a second modified example of the embodiment of the present disclosure. Phase shift mask 13 shown in Fig. 6 includes a light-shielding resist layer 4 on the other surface (rear surface) of substrate 1 included in phase shift mask 10 according to the embodiment of the present disclosure shown in Fig. 1. The structure according to the second modified example is not limited to a structure in which the phase shift mask 10 is formed, and for example, a general binary mask may be formed instead of the phase shift mask 10. In other words, a light-shielding resist layer 4 may be formed on the back surface of a general binary mask. Thus, the gist of the structure according to the second modified example is that a light-shielding resist is applied and formed on the rear surface of the mask (light-shielding resist layer 4 is formed).

[0030] The pattern shape of the light-shielding resist layer 4 formed on one surface of the substrate 1 may be different from the pattern shape of the light-shielding resist layer 4 formed on the other surface of the substrate 1 in a plan view. Alternatively, the pattern shape of the light-shielding resist layer 4 formed on one surface of the substrate 1 may be the same as the pattern shape of the light-shielding resist layer 4 formed on the other surface of the substrate 1 in a plan view. Phase shift mask 13 having such a configuration has light-shielding patterns formed on both sides of phase shift mask 13, making it possible to rework the back side, thereby reducing the frequency of replacing phase shift masks.

[0031] A method for manufacturing phase shift mask 13 according to a second modification of the embodiment of the present disclosure will now be described. 7A to 7C are schematic cross-sectional views illustrating a manufacturing process of a phase shift mask according to a second modified example of the embodiment of the present disclosure. Fig. 7(a) shows a phase shift mask 10 according to an embodiment of the present disclosure. Fig. 7(b) shows a process of applying a light-shielding resist 4 onto the other surface (rear surface) of a substrate 1 included in the phase shift mask 10. Fig. 7(c) shows a process of patterning and developing the applied light-shielding resist 4 to form a light-shielding resist layer 4 on the other surface (rear surface) of the substrate 1. In this manner, a phase shift mask 13 according to a second modified example of the embodiment of the present disclosure is manufactured. 7(b) and 7(c) may be performed before the step of forming the light-shielding resist layer 4 on one surface (front surface) of the substrate 1. In other words, the step of forming the light-shielding resist layer 4 on the other surface of the substrate 1 may be performed before the step of forming the light-shielding resist layer 4 on one surface of the substrate 1, or may be performed after the step of forming the light-shielding resist layer 4 on one surface of the substrate 1.

[0032] (Overall structure of a phase shift mask according to the prior art) For reference, the configuration of a phase shift mask 20 according to the prior art will be briefly described below. Fig. 8 is a schematic cross-sectional view showing the configuration of a phase shift mask according to the prior art. Phase shift mask 20 shown in Fig. 8 includes substrate 1 transparent to the exposure wavelength, phase shift layer 2 having a circuit pattern formed on substrate 1, and light-shielding layer (CrO film) 41 formed so as to cover the upper surface of phase shift layer 2 located in the non-exposed region.

[0033] For reference, a conventional method for manufacturing a phase shift mask 20 will be briefly described below. FIG. 9 is a schematic cross-sectional view showing a manufacturing process of the phase shift mask 20 shown in FIG. 8. FIG. 9(a) shows a process of laminating a phase shift layer 2, a light-shielding layer (CrO film) 41, and a resist 3 in this order on one surface (front surface) of a substrate 1. FIG. 9(b) shows a process of drawing and developing the resist 3 to form a patterned resist 3 on the light-shielding layer (CrO film) 41. FIG. 9(c) shows a process of etching the light-shielding layer (CrO film) 41 and the phase shift layer 2 using the patterned resist 3 as a mask. FIG. 9(d) shows a process of peeling off the resist 3 from the etched light-shielding layer (CrO film) 41. FIG. 9(e) shows a process of applying a resist 5 so as to cover the light-shielding layer (CrO film) 41. FIG. 9(f) shows a process of drawing and developing the resist 5 to form a patterned resist 5 on the light-shielding layer (CrO film) 41. Fig. 9(g) shows a process of etching and removing light-shielding layer (CrO film) 41 using patterned resist 5 as a mask. Fig. 9(h) shows a process of peeling off resist 5 from light-shielding layer (CrO film) 41. In this manner, phase shift mask 20 according to the conventional technology is manufactured.

[0034] In this way, the method for manufacturing a phase shift mask according to an embodiment of the present disclosure forms a light-shielding resist layer using a light-shielding resist, and therefore can eliminate a light-shielding layer formed of a CrO film, etc. Therefore, the method for manufacturing a phase shift mask according to an embodiment of the present disclosure does not require the steps shown in Fig. 9(c) and Fig. 9(g) (etching treatment of the CrO film, etc.) that were necessary in the method for manufacturing a phase shift mask according to the conventional technology. As a result, the method for manufacturing a phase shift mask according to the embodiment of the present disclosure can reduce (simplify) the number of steps in the entire manufacturing process, compared to the method for manufacturing a phase shift mask according to the conventional technology.

[0035] Furthermore, in the conventional phase shift mask manufacturing method, it is difficult to add or modify a light-shielding area after the mask is manufactured, and if it is necessary to change the light-shielding area, the mask must be manufactured again. However, in the case of the manufacturing method of a phase shift mask according to an embodiment of the present disclosure (redoing the process), a light-shielding resist layer is formed using a light-shielding resist, so that it is easy to add or modify light-shielding areas after the mask is manufactured, and there is no need to remanufacture the mask even if it is necessary to change the light-shielding area.

[0036] Moreover, for example, this embodiment can have the following configuration. (1) 1. A method for manufacturing a phase shift mask, comprising the steps of: forming a resist pattern having openings on an exposed surface of a phase shift layer formed on one surface of a substrate; etching a region of the phase shift layer exposed from the openings using the resist pattern as a mask; peeling the resist pattern from above the etched phase shift layer; applying a light-shielding resist to cover the phase shift layer from which the resist pattern has been peeled off; and patterning and developing the light-shielding resist to form a light-shielding layer patterned on the phase shift layer. (2) The method for producing a phase shift mask according to (1) above, wherein in the step of forming the resist pattern, the exposed surface of the phase shift layer is treated with a primer before the resist pattern is formed. (3) The method for manufacturing a phase shift mask described in (1) or (2) above, characterized in that in the process of applying the light-shielding resist, the exposed surface of the phase shift layer from which the resist pattern has been peeled off is subjected to a primer treatment, and then the light-shielding resist is applied. (4) peeling off the light-shielding layer formed on the patterned phase shift layer after the step of forming the patterned light-shielding layer; applying a light-shielding resist again to cover the phase shift layer from which the light-shielding layer has been peeled off; and forming a patterned light-shielding layer again on the phase shift layer by patterning and developing the re-applied light-shielding resist. (5) after the step of forming the patterned light-shielding layer, applying a light-shielding resist again to cover the phase shift layer; and forming a patterned light-shielding layer on the phase shift layer by patterning and developing the recoated light-shielding resist. (6) The method for manufacturing a phase shift mask described in any one of (1) to (5) above, further comprising a step of forming a patterned light-shielding layer on the other side of the substrate after the step of forming the patterned light-shielding layer or before the step of forming the resist pattern. (7) The method for manufacturing a phase shift mask described in (6) above, characterized in that the pattern shape of the light-shielding layer formed on one side of the substrate is different from the pattern shape of the light-shielding layer formed on the other side of the substrate in a planar view. (8) The method for manufacturing a phase shift mask described in (6) above, characterized in that the pattern shape of the light-shielding layer formed on one side of the substrate is the same as the pattern shape of the light-shielding layer formed on the other side of the substrate in a planar view. (9) A substrate, a phase shift layer patterned on one surface of the substrate, and a light-shielding layer formed on the phase shift layer, The phase shift mask according to claim 1, wherein the light-shielding layer is formed by laminating layers. (10) 1. A phase shift mask comprising: a substrate; a phase shift layer patterned on one surface of the substrate; a light-shielding layer formed on the phase shift layer; and a light-shielding layer patterned on the other surface of the substrate. [Industrial Applicability]

[0037] The present invention can provide a phase shift mask on which a fine pattern is formed with high precision, suitable for manufacturing logic devices of 28 nm or less, or memory devices of 30 nm or less. [Explanation of symbols]

[0038] 1. Substrate 2. Phase shift layer 3. Resist 4. Light-shielding resist layer (light-shielding resist) 41...Light blocking layer (CrO film) 5. Resist 10. Phase shift mask 11 Phase shift mask 12 Phase shift mask 13 Phase shift mask 20 Phase shift mask

Claims

1. forming a resist pattern having an opening on an exposed surface of a phase shift layer formed on one surface of a substrate; etching a region of the phase shift layer exposed through the opening by using the resist pattern as a mask; stripping the resist pattern from above the etched phase shift layer; applying a light-shielding resist to cover the phase shift layer from which the resist pattern has been peeled off; and forming a patterned light-shielding layer on the phase shift layer by patterning and developing the light-shielding resist.

2. 2. The method for producing a phase shift mask according to claim 1, wherein in the step of forming the resist pattern, the resist pattern is formed after the exposed surface of the phase shift layer is treated with a primer.

3. 2. The method for manufacturing a phase shift mask according to claim 1, wherein in the step of applying the light-shielding resist, the exposed surface of the phase shift layer from which the resist pattern has been stripped is subjected to a primer treatment, and then the light-shielding resist is applied.

4. peeling off the light-shielding layer formed on the patterned phase shift layer after the step of forming the patterned light-shielding layer; applying a light-shielding resist again to cover the phase shift layer from which the light-shielding layer has been peeled off; 2. The method of claim 1, further comprising the step of: patterning and developing the reapplied light-shielding resist to form a light-shielding layer patterned on the phase shift layer again.

5. after the step of forming the patterned light-shielding layer, applying a light-shielding resist again to cover the phase shift layer; 2. The method for producing a phase shift mask according to claim 1, further comprising the step of: patterning and developing the reapplied light-shielding resist to form a patterned light-shielding layer on the phase shift layer.

6. 2. The method for manufacturing a phase shift mask according to claim 1, further comprising the step of forming a patterned light-shielding layer on the other surface of the substrate after the step of forming the patterned light-shielding layer or before the step of forming the resist pattern.

7. 7. The method for manufacturing a phase shift mask according to claim 6, wherein a pattern shape of the light-shielding layer formed on one surface of the substrate is different from a pattern shape of the light-shielding layer formed on the other surface of the substrate in a plan view.

8. 7. The method for manufacturing a phase shift mask according to claim 6, wherein a pattern shape of the light-shielding layer formed on one surface of the substrate is the same as a pattern shape of the light-shielding layer formed on the other surface of the substrate in a plan view.

9. A substrate, a phase shift layer patterned on one surface of the substrate, and a light-shielding layer formed on the phase shift layer, The phase shift mask according to claim 1, wherein the light-shielding layer is formed by laminating layers.

10. 1. A phase shift mask comprising: a substrate; a phase shift layer patterned on one surface of the substrate; a light-shielding layer formed on the phase shift layer; and a light-shielding layer patterned on the other surface of the substrate.

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