JP3630929B2 - Method for manufacturing halftone phase shift mask - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a phase shift mask used for phase shift lithography, and more particularly to a method for manufacturing a halftone phase shift mask.
[0002]
[Prior art]
A phase shift mask is used as one of photomasks used when a fine pattern is transferred by a projection exposure apparatus in the manufacture of a semiconductor LSI or the like. This phase shift mask can improve the resolution of the transfer pattern by providing a phase difference between the exposure light passing through the mask. As one of the phase shift masks, a phase shift mask described in Japanese Patent Application Laid-Open No. 4-136854 is known particularly for a mask suitable for transferring isolated hole and line & space patterns.
[0003]
This phase shift mask forms a semi-transparent film (half-tone phase shift film) on the transparent substrate, which transmits light of an intensity that does not substantially contribute to exposure and simultaneously shifts the phase of the light passing therethrough. By selectively removing a part of the light-transmitting film and forming a semi-light-transmitting film pattern, a light-transmitting portion (transparent substrate exposed portion) that transmits light having an intensity that substantially contributes to exposure, and substantially And a semi-transparent portion that transmits light having an intensity that does not contribute to exposure. This phase shift mask shifts the phase of the light passing through the semi-translucent portion, so that the phase of the light passing through the semi-transparent portion is substantially inverted with respect to the phase of the light passing through the translucent portion. Thus, the contrast of the boundary portion can be satisfactorily maintained so that the light passing through the vicinity of the boundary between the semi-translucent portion and the translucent portion cancels each other and cancels each other. This is commonly referred to as a halftone phase shift mask.
In this phase shift mask, when the wavelength of the exposure light is λ and the refractive index of the semi-transparent film with respect to the exposure light is n, the thickness t of the semi-transparent film is
t = λ / {2 (n−1)}
Generally, it is set to a value satisfying the above, and the transmittance of the semi-transparent film at the wavelength of the exposure light is usually set to about 1 to 50%.
[0004]
As described above, the halftone phase shift mask has two functions of a phase shift function for shifting the phase of the exposure light by the semi-transparent portion and a light shielding function for substantially blocking the exposure light. . That is, this semi-transparent portion functions as a phase shift layer at the boundary portion of the pattern, and functions as a light shielding layer at other portions. Therefore, a slight amount of light leaks even in a portion where it is ideal to completely block exposure light. Normally, the entire exposure amount is adjusted so that the substantial exposure is not reached even if this leakage light is present.
As described above, since the halftone phase shift mask also serves as a light shielding function by the semi-translucent portion, in principle, it is not necessary to provide a light shielding film like a conventional general phase shift mask. . However, in order to cover the drawbacks of the halftone phase shift mask, a technique of providing a light shielding film on or below the semi-transparent film forming the semi-transparent part has been proposed. Hereinafter, the halftone phase shift mask according to this proposal will be described from the background of the proposal.
[0005]
As is well known, the halftone phase shift mask is usually used as a mask (reticle) of a reduction projection exposure apparatus (stepper) which is an exposure apparatus used in semiconductor manufacturing. This stepper performs reduction projection exposure by reducing a projection image obtained by projecting a reticle with exposure light using a projection lens and forming it on a semiconductor wafer as a transfer target. In this reduction projection exposure, usually, the same reticle pattern is repeatedly transferred to different positions on one semiconductor wafer and exposed to obtain a large number of semiconductor chips from one semiconductor wafer. Therefore, when pattern transfer is performed using this stepper, exposure is performed by covering the peripheral area of the mask so that only the transfer area of the phase shift mask (reticle) is exposed by the covering member (aperture) provided in the stepper. I do.
[0006]
However, it is difficult to install this aperture so as to expose only the transfer region with high accuracy (for example, with an accuracy of 1 μm inside or outside). In many cases, the aperture protrudes to the non-transfer region around the outer periphery of the transfer region. It will be exposed. Further, even if the aperture is highly accurate and there is no protruding portion, the exposure light is diffracted and reaches the transfer area because there is a distance between the aperture and the transfer object.
[0007]
As described above, it has been found that when the aperture allows the exposure light to pass through a wider range than the original transfer region, there is the following problem. That is, in a halftone phase shift mask, a semi-transparent film that passes light of an intensity that does not substantially contribute to exposure is usually formed in a non-transfer area. For this reason, as described above, when the exposure light passes through a wider range than the original transfer region, exposure is performed with light of an intensity that does not substantially contribute to the exposure at the protruding portion on the non-transfer region. Of course, even if this protruding portion is present, no problem occurs in one exposure. However, the portion exposed at the protruding portion (the protruding exposure portion) may overlap the transfer region, or may protrude and overlap the exposed portion at the next exposure. Even if the exposure amount does not substantially contribute to exposure in one exposure, they may be integrated to reach the amount contributing to exposure. Therefore, this results in the same thing as a result of exposing the area that should not be exposed, resulting in a defect.
Also, a pattern larger than a pattern size (approximately 0.3 to 0.5 μm for an i-line having a wavelength of 365 nm) that exhibits the original advantages of a halftone phase shift mask (approximately several to several tens of times larger). In this case, the side lobe effect becomes prominent in the vicinity of the pattern, and unnecessary resist film reduction may occur, resulting in defects.
[0008]
In order to eliminate the above disadvantages, a non-transfer area on the semi-transparent film formed in the non-transfer area and adjacent to the boundary between the transfer area and the non-transfer area has a light shielding width greater than a predetermined width. A halftone phase shift mask in which a portion is formed has been proposed (Japanese Patent Laid-Open No. 6-282063) (conventional example 1).
[0009]
FIG. 5 is a diagram for explaining a manufacturing process of the halftone phase shift mask according to the above proposal.
In this figure, a translucent light-shielding film 2a made of chromium is formed on a transparent substrate 1 by sputtering, and a phase shift film 2b made of SOG (spin-on-glass) is formed thereon by spin coating. The semi-transparent film 2a and the phase shift film 2b made of SOG constitute the semi-transparent film 2. Subsequently, a light shielding film 3 made of chromium is formed on the semi-transparent film 2 by a sputtering method, and a positive electron beam resist 4 is formed on the light shielding film 3 by a spin coating method (FIG. 5A). )).
Next, a resist pattern 41 is formed by electron beam drawing, and the light shielding film 3 is wet etched using the resist pattern 41 as a mask. Subsequently, the phase shift film 2b is dry etched to form the light shielding film pattern 31 and the phase shift film pattern 21b. (FIG. 5B).
Next, after peeling off the resist pattern 41, a negative electron beam resist 5 is formed by spin coating (FIG. 5C).
Next, a resist pattern 51 is formed by electron beam drawing, and the light shielding film pattern 31 and the semi-transmissive light shielding film 2a are wet-etched using the resist pattern 51 as a mask to form the light shielding film pattern 32 and the semi-transmissive light shielding film pattern 21a ( FIG. 5 (d)).
Finally, the resist pattern 51 is removed to obtain a desired halftone phase shift mask (FIG. 5E).
[0010]
However, in the above invention, the film structure formed on the transparent substrate is a structure of chromium / SOG / chromium. Therefore, in order to form a film having such a structure, a chromium film is formed in a vacuum apparatus. Then, it is necessary to form the SOG film by taking it out from the vacuum apparatus, applying SOG by spin coating, and firing it in a furnace, and then putting it in the vacuum apparatus again to form a chromium film. That is, there are problems that the process is complicated and takes time to manufacture, and that the process is complicated, so that the probability of occurrence of defects is high. Moreover, since chromium is processed after processing SOG, there is a high probability that defects will occur here. In addition, there is a problem in adhesion between SOG and chromium, and there is a possibility that chromium is peeled off from SOG or SOG is peeled off from chromium.
[0011]
In order to solve such problems, for example, a technique has been proposed in which a MoSiON single layer film is used as a semi-transparent film and a light shielding film made of chromium is formed thereon (Proc. SPIE, Vol 2621). , 266-272 (1995)) (conventional example 2).
[0012]
FIG. 6 is a diagram for explaining a manufacturing process of the halftone phase shift mask according to the above proposal.
In this figure, a semi-transparent film 2 made of MoSiON is formed on a transparent substrate 1 by a sputtering method, and a light-shielding film 3 made of chromium is formed on the semi-transparent film 2 by a sputtering method. A positive electron beam resist 4 is formed on the substrate by spin coating (FIG. 6A).
Next, a resist pattern 41 is formed by electron beam drawing, and the light shielding film 3 is wet-etched using the resist pattern 41 as a mask. Subsequently, the semi-transparent film 2 is dry-etched, so that the light-shielding film pattern 31 and the semi-transparent film pattern 21 are obtained. Is formed (FIG. 6B).
Next, after peeling off the resist pattern 41, a negative electron beam resist 5 is formed by spin coating (FIG. 6C).
Next, a resist pattern 51 is formed by electron beam drawing, and the light shielding film pattern 31 is wet-etched using the resist pattern 51 as a mask to form the light shielding film pattern 32 (FIG. 6D).
Finally, the resist pattern 51 is removed to obtain a desired halftone phase shift mask (FIG. 6E).
[0013]
[Problems to be solved by the invention]
However, in the halftone phase shift mask of the above-described conventional example 2, although the semi-transparent film is a single layer, both the mask blank manufacturing process and the mask manufacturing process are reduced as compared with the conventional example 1, but the following still remains. I found out there was a problem like this.
That is, in the mask manufacturing process, after etching the light-shielding film and the semi-transparent film and removing the resist, the resist is applied again, and the light-shielding film pattern is again patterned by electron beam drawing to form the light-shielding film pattern of the final shape. However, there is an uncorrectable missing defect or surplus defect that occurs during the processes such as developing or etching the resist when forming these films on the translucent film or the light-shielding film by a sputtering method or the like. In such a case, a series of steps such as resist application, drawing, development, etching, and resist removal for the second time are wasted. In other words, if all the manufacturing processes are not completed, it will not be possible to pass or fail, and the recovery when it becomes a defective product (such as arranging production again and starting production) will be delayed. . In addition, the semi-transparent film is more difficult to detect defects with the automatic defect inspection apparatus than the light shielding film.
[0014]
The present invention has been made under the background described above, and provides a manufacturing method of a phase shift mask that can reduce manufacturing waste, perform defect inspection easily and with high accuracy, and easily perform defect correction with high accuracy. Objective.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, a halftone phase shift mask manufacturing method of the present invention has the following configuration.
[0016]
(Configuration 1) In a method of manufacturing a halftone phase shift mask having a pattern of a semi-transparent film and a light shielding film on a transparent substrate, a semi-transparent film and a light shielding film are sequentially formed on the transparent substrate, and further on the light shielding film Forming a resist pattern on the substrate, etching the light shielding film using the resist pattern as a mask, forming a light shielding film pattern, and etching the semi-transparent film using the resist pattern and the light shielding film pattern as a mask. A step of forming a semi-transparent film pattern, a step of performing a defect inspection based on at least the light shielding film pattern, a resist pattern formed on the light shielding film pattern, and using the resist pattern as a mask A step of forming a light-shielding film pattern having a final shape by etching the light-shielding film pattern. Method of manufacturing over emission type phase shift mask.
[0017]
(Structure 2) The method for manufacturing a halftone phase shift mask according to Structure 1, wherein the defect inspection step is performed after the resist pattern is peeled off and the cleaning step.
[0018]
(Configuration 3) In the defect inspection step, if there is a missing defect or a surplus defect that can be corrected, the surplus defect is corrected on the spot, and the isolated missing defect is also corrected on the spot to form a pattern edge. The method for manufacturing a halftone phase shift mask according to Configuration 1 or 2, wherein the missing defect is corrected in a final process.
[0019]
(Configuration 4) Excess light shielding film defects remaining on the semi-transparent film detected in the defect inspection after completion of the mask are corrected by etching on the edge of the light shielding film pattern, and other defects are left as they are. A method for manufacturing a halftone phase shift mask according to Configuration 3, wherein:
[0020]
[Action]
In the present invention, it is possible to eliminate manufacturing waste by stopping the manufacturing when it is determined that a defect cannot be corrected by performing a defect inspection during the mask manufacturing process. In other words, in the normal manufacturing process in which defect inspection is performed after the mask is completed, if there are missing or surplus defects that are determined to be uncorrectable, it will be recreated from the beginning. However, according to the present invention, a series of steps such as resist application, drawing, development, etching, and resist removal for the second time can be omitted. Further, by performing defect correction in the middle of the manufacturing process, the inspection process in the final mask state is simplified.
[0021]
In the present invention, the defect inspection of the semi-transparent film can be performed in a state where the same light-shielding film pattern exists on the semi-transparent film pattern (the defect inspection can be performed based on the light-shielding film pattern). Therefore, defect inspection can be performed easily and with high accuracy. That is, in the automatic defect inspection apparatus, the light-shielding film is easier to detect the defect than the semi-transparent film, so that a more accurate inspection can be performed. Also, when inspecting using an optical microscope, the light-shielding film is easier to recognize patterns and defects than the semi-transparent film.
[0022]
Furthermore, in the present invention, since the defect correction of the semi-transparent film can be performed in a state where the same light-shielding film pattern exists on the semi-transparent film pattern, the defect correction can be performed easily and with high accuracy. That is, when correcting a surplus defect with a laser repair device, the light-shielding film absorbs laser light more easily than the semi-transparent film, so that it can be corrected with low power and damage to the underlying glass substrate is small. Similarly, since the particles scattered by the laser light are deposited again on the light shielding film, they are finally removed, and the scattered particles do not remain on the semi-transparent film (the light shielding film is finally etched). To expose the semi-transparent film). Even when correction is performed by the FIB apparatus, the image can be easily recognized and can be corrected with high accuracy.
[0023]
【Example】
Hereinafter, the present invention will be described in detail based on examples.
[0024]
Example 1
FIG. 1 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to an embodiment of the present invention.
[0025]
As shown in the figure, first, after a predetermined cleaning is performed on a transparent substrate 1 made of quartz glass (size 6 inch square, thickness 0.25 inch) whose surface has been polished, A translucent film 2 made of molybdenum, silicon, oxygen, and nitrogen was formed by a sputtering method to a thickness of 160 nm, and subsequently, a light-shielding film 3 made of chromium was formed to a thickness of 100 nm. On this light-shielding film 3, a positive electron beam resist (EBR-9: manufactured by Toray Industries, Inc.) 4 was applied at a film thickness of 500 nm by a spin coating method and baked (FIG. 1A).
[0026]
Then, a desired pattern was drawn on the positive electron beam resist 4 and developed to form a resist pattern 41. Subsequently, using the resist pattern 41 as a mask, the light shielding film 3 is wet-etched using an etchant composed of ceric ammonium nitrate and perchloric acid to form a first light shielding film pattern 31 (FIG. 1). (B)).
[0027]
Next, using the resist pattern 41 and the first light shielding film pattern 31 as a mask, an etching gas: CF₄/ O₂A semi-transparent film pattern 21 was formed by dry-etching the semi-transparent film 2 under the conditions of the mixed gas, pressure: 0.4 Torr, and RF power: 100 W (FIG. 1C).
[0028]
Next, after the resist was peeled off and subjected to predetermined cleaning, a defect inspection was performed (FIG. 1 (d)).
As a result, surplus defects and missing defects that could not be corrected were discovered, so that it was not possible to proceed to the subsequent process, and preparation for mask fabrication was started again.
[0029]
Example 2
FIG. 2 is a diagram for explaining a halftone phase shift mask manufacturing process according to another embodiment of the present invention. The process up to the middle is the same as in FIG. 1 and will be described with reference to FIG.
[0030]
First, a predetermined cleaning is performed on a transparent substrate 1 made of quartz glass (6 inch square, 0.25 inch thick) whose surface is polished, and then molybdenum, silicon, oxygen, nitrogen is formed on the transparent substrate 1. The semi-transparent film 2 made of was formed with a film thickness of 160 nm by a sputtering method, and subsequently, the light shielding film 3 made of chromium was formed with a film thickness of 100 nm. On this light-shielding film 3, a positive electron beam resist (EBR-9: manufactured by Toray Industries, Inc.) 4 was applied at a film thickness of 500 nm by a spin coating method and baked (FIG. 1A).
[0031]
Then, a desired pattern was drawn on the positive electron beam resist 4 and developed to form a resist pattern 41. Subsequently, using the resist pattern 41 as a mask, the light shielding film 3 is wet-etched using an etchant composed of ceric ammonium nitrate and perchloric acid to form a first light shielding film pattern 31 (FIG. 1). (B)).
[0032]
Next, using the resist pattern 41 and the first light shielding film pattern 31 as a mask, an etching gas: CF₄/ O₂A semi-transparent film pattern 21 was formed by dry-etching the semi-transparent film 2 under the conditions of the mixed gas, pressure: 0.4 Torr and RF power: 100 W (FIG. 1C).
[0033]
Next, after the resist pattern 41 was peeled off and subjected to predetermined cleaning, a defect inspection was performed (FIG. 1D).
[0034]
As a result of the defect inspection, a surplus defect that can be corrected (the isolated black defect 5 and the black defect 6 on the edge) was found (FIG. 2A). Therefore, the repair was performed in the same manner as a normal Cr photomask was repaired by a repair device using a YAG laser (FIG. 2B).
[0035]
After the above correction, a positive electron beam resist (EBR-9: manufactured by Toray Industries, Inc.) 7 was applied at a film thickness of 500 nm by a spin coating method and baked (FIG. 2C).
[0036]
Next, a desired pattern was drawn on the positive electron beam resist 7 and developed to form a resist pattern 71. Subsequently, using the resist pattern 71 as a mask, the light shielding film pattern 31 is wet-etched again using an etchant composed of ceric ammonium nitrate and perchloric acid, and the second (final shape) light shielding film pattern 32 is obtained. Was formed (FIG. 2D).
[0037]
Finally, the resist pattern 71 was peeled off and subjected to a predetermined cleaning, and then a defect inspection was performed again. As a result, no defects were detected, and a high-quality halftone phase shift mask was efficiently obtained ( FIG. 2 (e)).
[0038]
Example 3
FIG. 3 is a diagram for explaining a halftone phase shift mask manufacturing process according to another embodiment of the present invention. The process up to the middle is the same as in FIG. 1 and will be described with reference to FIG.
[0039]
First, a predetermined cleaning is performed on a transparent substrate 1 made of quartz glass (6 inch square, 0.25 inch thick) whose surface is polished, and then molybdenum, silicon, oxygen, nitrogen is formed on the transparent substrate 1. The semi-transparent film 2 made of was formed with a film thickness of 160 nm by a sputtering method, and subsequently, the light shielding film 3 made of chromium was formed with a film thickness of 100 nm. On this light-shielding film 3, a positive electron beam resist (EBR-9: manufactured by Toray Industries, Inc.) 4 was applied at a film thickness of 500 nm by a spin coating method and baked (FIG. 1A).
[0040]
Then, a desired pattern was drawn on the positive electron beam resist 4 and developed to form a resist pattern 41. Subsequently, using the resist pattern 41 as a mask, the light shielding film 3 is wet-etched using an etchant composed of ceric ammonium nitrate and perchloric acid to form a first light shielding film pattern 31 (FIG. 1). (B)).
[0041]
Next, using the resist pattern 41 and the first light shielding film pattern 31 as a mask, an etching gas: CF₄/ O₂A semi-transparent film pattern 21 was formed by dry-etching the semi-transparent film 2 under the conditions of the mixed gas, pressure: 0.4 Torr and RF power: 100 W (FIG. 1C).
[0042]
Next, after the resist was peeled off and subjected to predetermined cleaning, a defect inspection was performed (FIG. 1 (d)).
[0043]
As a result of the defect inspection, a defect defect that can be corrected (isolated white defect (pinhole) 8 and white defect 9 on the edge) was found (FIG. 3A). Thus, the isolated white defect (pinhole) 8 is corrected by depositing a carbon film 81 of about 3000 angstroms in the same way as a normal Cr photomask is corrected, and the white defect 9 on the edge is corrected. It was left as it was (FIG.3 (b)).
[0044]
After the above partial correction, a positive electron beam resist (EBR-9: manufactured by Toray Industries, Inc.) 7 was applied at a film thickness of 500 nm by a spin coating method and baked (FIG. 3C).
[0045]
Next, a desired pattern was drawn on the positive electron beam resist 7 and developed to form a resist pattern 71. Subsequently, using the resist pattern 71 as a mask, the light shielding film pattern 31 is wet-etched again using an etchant composed of ceric ammonium nitrate and perchloric acid, and the second (final shape) light shielding film pattern 32 is obtained. Was formed (FIG. 3D).
[0046]
Finally, after the resist pattern 71 was peeled off and subjected to a predetermined cleaning, the defect inspection was performed again. The defect was detected because it was hidden in the white defect 9 on the edge and the light shielding film already detected above. An isolated white defect (pinhole) 10 on the semi-transparent film pattern 21 that was not detected was detected. Thus, the isolated white defect (pinhole) 10 is corrected by depositing a carbon film 101 of about 3000 angstroms in the same way as a normal Cr photomask is corrected by the FIB apparatus, and the white defect 9 on the edge is also corrected. Similarly, a carbon film 91 was deposited and corrected. As a result, it was possible to efficiently obtain a high-quality halftone phase shift mask that has no problem in transferring to a wafer (FIG. 3 (e)).
[0047]
Example 4
In Example 4, a defect inspection was performed on the final mask after the resist pattern was finally peeled off and subjected to predetermined cleaning in the same manner as in Examples 2 and 3, and as shown in FIG. In addition, there is an excess light shielding film defect (the isolated black defect 11 and the black defect 12 on the edge) on the semi-transparent film pattern 21. In this case, the black defect 12 on the edge of the semi-transparent film pattern 21 was etched using an etching solution, and the isolated black defect 11 was left as it was. As a result, it was possible to efficiently obtain a high-quality halftone type phase shift mask having no problem in transferring to a wafer (FIG. 4B).
As described above, according to the present invention, a high-quality halftone phase shift mask that does not cause any problem in transferring to a wafer even if a defect occurs only by adding a relatively simple inspection process in the middle of the process. Can be obtained efficiently and in a short time.
[0048]
Although the present invention has been described with reference to the preferred embodiments, the present invention is not necessarily limited to the above embodiments.
[0049]
For example, the missing defect on the pattern edge is not limited to a method of correcting by the FIB (focus ion beam) method. For example, a portion other than the missing defect portion is masked with a resist or the like, and only carbon or the like is masked on the missing defect portion. A method of depositing a correction film is also possible.
[0050]
Further, the semi-transparent film is not limited to one made of molybdenum, silicon, oxygen, and nitrogen, and is selected from, for example, a semi-transparent film made of molybdenum, silicon, oxygen, and nitrogen, tungsten, titanium, tantalum, and chromium. It may be a semi-transparent film made of a metal, silicon, oxygen and / or nitrogen.
[0051]
Furthermore, the light shielding film is not limited to chromium, for example, a material containing chromium and at least one selected from oxygen, nitrogen, and carbon, a film of aluminum, titanium, tungsten, molybdenum silicide (MoSi), Alternatively, it may be made of a material containing at least one selected from oxygen, nitrogen, and carbon.
[0052]
【The invention's effect】
As described above, according to the method of manufacturing a halftone phase shift mask of the present invention, there is little manufacturing waste, defect inspection can be performed easily and with high accuracy, and defect correction can be performed easily and with high accuracy. .
Therefore, a halftone phase shift mask can be manufactured easily and inexpensively with a high yield.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to a first embodiment of the invention;
FIG. 2 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to a second embodiment of the invention;
FIG. 3 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to a third embodiment of the invention;
FIG. 4 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to a fourth embodiment of the invention;
5 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to Conventional Example 1. FIG.
6 is a diagram for explaining a manufacturing process of a halftone phase shift mask according to Conventional Example 2. FIG.
[Explanation of symbols]
1 Transparent substrate
2 Semi-translucent membrane
3 Shading film
4 resists
5 Isolated black defects
6 Black defect on the edge
7 resist
8 Isolated white defect (pinhole)
9 White defect on the edge
10 Isolated white defect (pinhole) of semi-translucent film
11 Isolated black defect on light-shielding film pattern
12 Black defect on the edge of the light shielding film pattern
21 Semi-transparent film pattern
31 Light-shielding film pattern
32 Final shape shading film pattern
41 resist pattern
71 resist pattern

Claims (3)

In a method for producing a halftone phase shift mask having a pattern of a semi-transparent film and a light-shielding film on a transparent substrate,
A step of sequentially forming a translucent film and a light shielding film on a transparent substrate, and further forming a resist pattern on the light shielding film;
Etching the light shielding film using the resist pattern as a mask to form a light shielding film pattern;
Etching the semi-transparent film using the resist pattern and the light-shielding film pattern as a mask to form a semi-transparent film pattern;
Forming a resist pattern on the light-shielding film pattern, and forming the light-shielding film pattern having a final shape by etching the light-shielding film pattern using the resist pattern as a mask;
A process of performing defect inspection after the mask is completed ;
Have
Excess light-shielding film defects remaining on the semi-transparent film detected in the defect inspection after completion of the mask should be corrected by etching on the edge of the semi-transparent film pattern, and other defects should be left as they are. A method of manufacturing a characteristic halftone phase shift mask. 2. The method according to claim 1 , further comprising a step of performing a defect inspection based on the light shielding film pattern after the resist pattern is peeled off and subjected to predetermined cleaning after the step of forming the semi-transparent film pattern. The manufacturing method of the halftone type phase shift mask of description. In the defect inspection step after the step of forming the semi-transparent film pattern, if there is a missing defect or a surplus defect that can be corrected, the surplus defect is corrected on the spot, and the isolated missing defect is also 3. The method of manufacturing a halftone phase shift mask according to claim 2, wherein the defect is corrected in the field, and the missing defect on the pattern edge is corrected in the final step.

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