JPH0980741A - Method for correcting defect of halftone phase shift mask and halftone phase shift mask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the influence of a method for correcting defects on transfer patterns by providing a phase shift mask with light shielding films in a shape to completely cover void defects and to partially cover the end of the plural opening patterns adjacent to the patterns. SOLUTION: The void defect 3 exists on the halftone phase shift line patterns 2 of the mask patterns 1. A defect correcting part 4 and correcting parts 5, 6 for correcting the shape are formed out of carbon films in this part by using a correction method by light shielding. The correcting parts 5, 6 for correcting the shape are formed by the method similar to the method for forming the defect correcting part 4. While these correcting parts are separate patterns in terms of design and have a separate kind of role, the correcting parts are formable simultaneously with the defect correcting part 4 in terms of the forming stage and there is no need for newly adding the stage. Optimum sizes are determined for the size of the correcting parts 5, 6 for correcting the shape according to the size of the defect correcting part 4. The widths A, A' of the correcting parts 5, 6 for correcting the shape suffice usually with the values within a range of 0.02 to 0.1μm and A, A' suffice with the same value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halftone phase shift mask used for forming a fine pattern in an optical lithography process for fine processing in various fields represented by a semiconductor manufacturing process, and particularly Defect repair method.

[0002]

2. Description of the Related Art Phase shift mask technology is a kind of so-called super-resolution technology in photolithography technology and has been actively developed in recent years. What is a phase shift mask?
Unlike a conventional photomask (or reticle), it does not have a pattern consisting of a simple light-transmitting portion and a light-shielding portion, but at least does not reverse the phase of the transmitted light and the phase of the transmitted light. It is a general term for photomasks (or reticles) that include a transmissive portion. And
It is known that the phase shift mask has a dramatically excellent effect in improving the resolution and the depth of focus of a fine pattern, as compared with a conventional photomask that does not use the phase shift technique. The phase shift mask is further subdivided from the viewpoint of structure (or method), and one of them is the halftone phase shift mask according to the present invention.

The halftone phase shift mask has an optical transmittance such that the resist is not exposed to light (optical transmittance of about 10% is generally used, but the optical transmittance value is not limited). A pattern composed of a semi-transparent layer (hereinafter referred to as "semi-transparent pattern") is provided, and with respect to the semi-transparent pattern, a phase inversion function of transmitted light near the pattern edge and a light-shielding function inside the pattern, By making the edge shape of the transmitted light intensity distribution steep by providing the role of generating two effects, the resolution and depth of focus characteristics of projection exposure transfer are significantly improved compared to conventional photomasks. At the same time, the desired pattern on the transfer surface (for example, the resist surface on the wafer in the case of a semiconductor manufacturing process) is converted into an optical image consisting of the light intensity distribution. Those with the effect of faithfully formed. (Here, the “mask pattern” refers to a pattern formed on a mask and used for projection exposure transfer, and by performing projection exposure through this mask, an optical image having a desired pattern is obtained on the transfer surface. (It is a pattern that can be used.) (In addition, it is used by being attached to a sequential movement type reduction projection exposure apparatus (commonly called "stepper"), and has a pattern enlarged to a fine pattern dimension to be obtained by projection exposure transfer. In some cases, the present invention can be applied to both a halftone phase shift mask and a halftone phase shift reticle according to such a representation method.

When manufacturing the halftone phase shift mask (itself), a mask pattern defect may occur in the lithography process during the manufacturing process. The present invention relates to a defect due to the lack of the semi-transparent pattern, that is, a so-called "whitening defect" among the defects, and a mode of the whitening defect of the halftone phase shift mask is shown in FIG. There is something like this. The dimensions of the mask pattern described below are all 1 × magnification when transferred onto a wafer. If the halftone phase shift mask is a halftone phase shift reticle and is called, for example, a “5-fold reticle”,
The size of the pattern on the halftone phase shift mask is 5 times the size of the pattern transferred on the wafer. FIG.
(A) and (c) are line and space patterns having a width of 0.4 μm, and white defects p1 and p3 (each having a diameter of 0.2 μm) are present. 2B and 2D show 0.4 μm square contact hole patterns with an interval of 0.4.
.mu.m, white defects p2 and p4 respectively
(Each having a diameter of 0.2 μm). As shown
The white defects p1, p2, p3, p4 are in contact with or adjacent to the adjacent opening patterns.

If the halftone phase shift mask has such a defect, the following problems occur during exposure and transfer. That is, the defect itself is transferred, and depending on the size and shape of the defect and the position where the defect exists, the white defect itself of the halftone phase shift mask may be generated due to the relationship of the light intensity on the transfer surface. However, even if the pattern is not actually transferred, the shape and size of the surrounding pattern are affected by the “optical proximity effect”, and the pattern is deformed. If a semiconductor integrated circuit is manufactured by an optical lithography process that causes such a problem, a serious accident such as malfunction of the product circuit may occur. Therefore, in general, photomask defects are rigorously inspected at the manufacturing stage, and if there are uncorrectable defects, the product is defective, and if they are correctable defects, all defects must be corrected. did not become. However, in this case, in order to correct a minute defect of 1 μm or less (in a 5 times reticle) with a small object, it is possible to use an extremely high-performance repair device that enables extremely delicate and highly accurate work. It becomes an essential requirement.

Now, as a conventional defect repairing method for a photomask having no halftone phase shift pattern portion (hereinafter referred to as "normal photomask"),
The method generally used at this stage is a correction method in which a carbon film is applied using a focused ion beam (FIB) device in the case of the above-mentioned white defect, which enables highly accurate correction. Is. In addition to this, although a metal film forming method by a lift-off process and the like are available for the time being, since they are inferior to the FIB device in terms of accuracy and efficiency, they are usually not used so much for defect correction of photomasks. There is. These means are technically established at present, and they can be corrected to a level that does not pose a problem in the case of a normal photomask, and the mask pattern after correction has the same high precision as in the case of no defect. A transfer pattern can be obtained. Even in the case of the halftone phase shift mask according to the present invention, since there is no essential difference in the film material itself, the same correction method as in the case of the normal photomask can be adopted (there are problems described later). It's possible (although) just for the sake of work, and so far this has been used to actually fix it.

However, in the case of the defect correction of the halftone phase shift mask, the correction of the white defect has a big problem. The problem is that in the correction method of forming a light-shielding film (film having a light-shielding property) with a carbon film using the FIB device, a light-shielding portion (having a transmittance of almost 0) is formed to cover the defective portion. In order to 2. The halftone phase shift pattern part, which should originally be a semi-transparent part, is missing, and only the modified part becomes a "light-shielding part". The point is that the "phase inversion effect of transmitted light" also disappears. That is, this causes the halftone phase shift effect of the corrected portion to be insufficient, which has a serious adverse effect on the characteristics of the transfer pattern in that the original halftone phase shift effect cannot be obtained. In the case of this correction method, for example, FIG.
When the defect extends to the pattern edge as in (b) or (b), the region of the formed light-shielding film protrudes into the opening, or conversely, the region of the light-shielding film leaves the defect partially uncovered. To avoid leaving a dent in the halftone phase shift pattern, it is necessary to accurately position the correction part along the original shape of the halftone phase shift pattern to form the light shielding part with high accuracy. Was required. Therefore, in the actual repair work, if the light-shielding film region protrudes from the desired correction portion, there is a problem that the protruding portion has to be removed using a (for example) highly accurate laser correction device. It was

Ideally, of course, this may be corrected by completely recovering the halftone phase shift portion itself as originally desired with respect to the white defect, that is, the halftone phase shift portion. It suffices to use a material that can be used for the above, and to repair it so that the transmittance and the phase difference of the transmitted light should be originally provided at that location. However, as a matter of practical correspondence, in consideration of the refractive index of the material, the thickness of the layer, and the transmittance in order to modify the transmittance and the phase difference of the transmitted light as described above, the white defect portion has the same quality as the surrounding area. This work is extremely difficult if (or equivalent) material is accurately embedded and the film thickness is adjusted to be uniform so that it does not protrude from the desired pattern, especially for micro defects on the submicron order. It is no exaggeration to say that applying this work is impossible at present for actual production. Therefore, it is practical to adopt a correction method of forming a light-shielding film with the carbon film (hereinafter, referred to as "light-shielding correction method").

Next, the result of the inventor's examination of the effect on the transfer pattern when the light-shielding correction method is actually used will be described. 3A to 3D are pattern diagrams corrected by the conventional defect correction method using the pattern diagrams including the white defects shown in FIGS. 2A to 2D. Note that FIGS. 3A to 3D and FIGS. 2A to 2D have a corresponding relationship. FIGS. 3A to 3D show defect correction parts r1, r2, r3 and r4 (the size of these four examples is 0.3 × 0.3 μm) so as to completely cover the white defects. There is a state in which the halftone phase shift pattern is arranged so as to be close to at least the opening so as not to stick out from the original halftone phase shift pattern and not to be bited. If a simple white defect of a light-shielding pattern like a normal photomask is to be repaired, a corrective light-shielding film is applied so that the state shown in FIG. The transfer pattern exposed on the resist surface on the wafer)
A pattern equivalent to that obtained by projection exposure with a defect-free mask pattern can be obtained.

However, in the case of repairing the white defect of the halftone phase shift mask, the following situation occurs. FIGS. 4A and 4B show patterns transferred using the correction patterns of FIGS. 3A and 3B. Here, the optical conditions for projection exposure transfer were a wavelength of 365 nm, a numerical aperture of 0.6, a coherence degree of 0.3, and a mask halftone phase shift portion transmittance of 8%. As described above, the effect of the halftone phase shift mask is due to the phase inversion effect of the exposure / transmitted light in the vicinity of the pattern edge. Therefore, if the white defect is in the vicinity of the pattern edge, FIG. ), The modified portion is a complete light-shielding portion, and the surrounding pattern is a halftone phase shift portion and a transmissive portion. This is different from the light intensity distribution in the case of a defective mask pattern. Moreover, when this is projected and exposed and transferred, the transfer pattern is curvedly deformed (recessed) at both ends of the line pattern as shown in FIG. The cause of the dents on both ends is not only the right end of the line pattern with the correction part, but the light-shielding part also affects the surroundings by the proximity effect, and therefore the left end also has a curved deformation (dent). It is thought that By the way,
This phenomenon can be confirmed even by performing a light intensity distribution simulation under the same conditions.

The profile shown by the solid line in FIG. 6 is shown in FIG.
It is sectional drawing of the light intensity distribution on the line segment which connects x1-x1 'in (a). The dotted line shows the light intensity distribution in the case of no defect. From this figure, it can be seen that the defect correction by the conventional method affects the light intensity at both ends of the line pattern having the correction portion.

Further, in addition to this, transfer patterns are similarly obtained for FIGS. 3B to 3D, and the results are shown in FIGS. 4B to 4D. According to this,
4C shows the curved deformation at both ends of the line edge as in FIG. 4A, and in the contact hole patterns of FIGS. 4B and 4D, two round shapes are slightly pulled toward the center side. It was transformed into a shape similar to the egg shape that it was made. From these results, it has become clear that the influence of the shading correction method on the transfer pattern also appears in that the transfer pattern is deformed. This means that the white defect is not transferred as a defect when it is shielded from light, but it has an effect of deforming the surrounding pattern because the optical proximity effect changes. That is, since only the correction portion is the light shielding portion, there is no transmitted light component, the phase inversion action is not performed near the pattern edge in the halftone phase shift portion, and the light intensity distribution is deteriorated. Therefore, it is possible to prevent the defect itself from being transferred by a simple conventional correction method,
It was clarified that the modification causes an adverse effect of causing deformation to the adjacent pattern. Especially,
As in the case of FIG. 3, for a dense array pattern,
Even if the pattern is not in contact with the defect repairing part, there is an effect such as deformation of the pattern shape or dimensional change on a plurality of adjacent patterns.

As described above, the conventional method for correcting the white defect in the halftone phase shift mask is performed even if the method is already established technically to cope with the conventional normal photomask. However, since the same characteristics as the design pattern cannot be obtained, the exposure transfer pattern is adversely affected, the transfer characteristics of the pattern are deteriorated, and there is a problem that this effect may affect a plurality of adjacent patterns. It was

A method for correcting white defects in a halftone phase shift mask is disclosed in Japanese Patent Laid-Open No. 7-1465.
According to Japanese Patent Laid-Open No. 44-44, transfer is performed by forming a light-shielding portion on a defective portion and a region protruding from the boundary between the transmissive portion included in the defective portion and the halftone phase shift portion by a predetermined length to the opening pattern. It has been proposed that the pattern shape can be corrected. However, according to the study by the inventor, the “correction of the transfer pattern shape” disclosed in the above proposal is only for the opening pattern in which the defect is in contact with and / or close to, and as shown in FIG. In a densely arranged pattern, even if the defect is not in contact with or / or is not close to the opening pattern, the proximity effect of the defect correction portion itself due to the light shielding related to the light shielding portion causes However, there was a problem that it had an influence on the transfer.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a method for correcting a white defect in a halftone phase shift mask. In addition to eliminating the drawbacks of the conventional defect repairing method, the effect is surely obtained and the process is simple, and the influence of the defect repairing method on the transfer pattern is particularly noticeable for a dense array pattern. It is an object of the present invention to provide a defect correction method and a halftone phase shift mask that can suppress and correct to a minimum and obtain a highly accurate transfer pattern.

[0016]

[Means for Solving the Problems] Means provided by the present invention for solving the above-mentioned problems are as follows:
In the case of correcting the white defect of the pattern of the halftone phase shift mask formed on the transparent substrate, the pattern having both the translucency and the phase inversion property with respect to the transmitted light as shown in FIG. Completely covers
Further, it is a method of repairing a defect of a halftone phase shift mask, characterized in that a light shielding film is provided in a shape that also partially covers respective ends of a plurality of opening patterns adjacent to the pattern. According to this, for a plurality of opening patterns adjacent to the part of the semi-transparent pattern having a white defect,
By providing a light-shielding film in a shape that also covers the end portions of each of the plurality of opening patterns (that is, not only for only one of the adjacent opening patterns), the semi-transparent pattern having the blank defect and the light-shielding pattern are shielded. In combination with the film, the above-mentioned distortion does not occur, and a light intensity distribution generated by the original halftone phase shift pattern (without white defects) can be created.

More preferably, as described in claim 2, the shape of the light shielding film is either a single rectangle or a combination of a plurality of rectangles. A method of repairing a defect of a halftone phase shift mask according to claim 1. The use of a rectangle is preferable in that the pattern itself is formed into a rectangle and the four sides are straight lines, so that if a rectangle is used for the shape of the light-shielding film, the matching with the pattern end portion is good. Because.

More preferably, as shown in claim 3, the pattern of the light-shielding film has symmetry, and the defect correction of the halftone phase shift mask according to claim 1 or 2, Is the way. It is to be noted that the pattern of the light-shielding film is provided with symmetry (a great difference from the situation at the time of transfer exposure of a large pattern) under a situation where the influence of the optical proximity effect is great as in the case of transfer exposure of such a fine pattern. Then, if a light-shielding film is applied to only one side of the pattern to correct it, the shape of the latent image consisting of high and low light intensity distributions will be adversely affected on the other side of (close to) the pattern, so avoid this. This is because it is preferable in that respect. In addition, "the pattern of the light-shielding film has a symmetry" means that "the pattern of the light-shielding film simply has a symmetry in shape".
And "the lengths of the light-shielding films protruding to the adjacent opening patterns are the same", or both are satisfied at the same time.

Alternatively, as described in claim 4, there is provided a halftone phase shift mask, wherein a pattern having both translucency and phase inversion property for transmitted light is provided on a transparent substrate, and at least a part of the pattern. Is a halftone phase shift mask, characterized in that a light-shielding film is provided in a shape that also partially covers the respective end portions of a plurality of opening patterns adjacent to the pattern. According to this halftone phase shift mask, even if there is a white defect under the light-shielding film, a plurality of opening patterns adjacent to the semitransparent pattern portion having the white defect, that is, the adjacent opening patterns By providing a light-shielding film in a shape that covers not only one of them but also the end portions of each of the plurality of opening patterns, while combining the semi-transparent pattern having the white defect and the light-shielding film, It is possible to create a light intensity distribution generated by the original halftone phase shift pattern (without white defects) without such distortion.

Alternatively, as described in claim 5, there is provided a halftone phase shift mask which is modified by the defect repairing method for a halftone phase shift mask according to any one of claims 1 to 3. . According to this halftone phase shift mask, even if there is a white defect under the light shielding film (similar to claim 4), a plurality of opening patterns adjacent to the semitransparent pattern portion having the white defect are formed. On the other hand, by providing a light-shielding film in a shape that covers not only one of the adjacent opening patterns but also the end portions of each of the plurality of opening patterns, the semi-transparent pattern having the white defect With the combination of the light shielding film and the light shielding film, it is possible to create the light intensity distribution generated by the original halftone phase shift pattern (without white defects) without the distortion as described above. Furthermore, the pattern itself is composed of rectangles,
Since the four sides are straight lines, it is preferable to use a rectangle for the shape of the light-shielding film in terms of good matching with the pattern end portion. In addition, when the pattern of the light-shielding film has symmetry (a large difference from the situation at the time of transfer exposure of a large pattern), under the situation where the influence of the optical proximity effect is large as in the case of transfer exposure of such a fine pattern, If a light-shielding film is applied to only one side of the pattern to correct it, the shape of the latent image consisting of high and low light intensity distribution will be adversely affected on the other side of (close to) the pattern, so avoid this. Is preferred.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION As a material for a light-shielding film provided for the purpose of correction in the present invention, a light-shielding film material which is usually used (in the photomask field in a broad sense) such as chromium, tantalum oxide, and MoSi is used. , And a metal material such as tungsten, molybdenum, or tantalum, or a carbon film is suitable. For example, when a film made of a material typified by carbon is applied to the film forming operation, a FIB device capable of forming a minute light-shielding portion with high accuracy can be preferably used.

Hereinafter, the manufacturing process of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is a diagram showing a method of correcting a white defect in a halftone phase shift mask according to the present invention. FIG. 1A is the same as FIG. 2B, in which there is a white defect 3 on the halftone phase shift line pattern 2 in the mask pattern 1. It is shown that the defect correction section 4 and the shape correction correction sections 5 and 6 were formed by using the above-described light shielding correction method using the carbon film. Here, the defect correction section 4 is based on the conventional defect correction method, and in the present invention, shape correction correction sections 5 and 6 are further added. The shape correction correction portion is formed by a method similar to that of the defect correction portion and has a different pattern in design and plays a different role, but can be formed simultaneously with the defect correction portion in the forming process. Therefore, it is not necessary to add a new process. The size of the shape correction correction parts 5 and 6 is required to be optimum according to the size of the defect correction part. The optimum size can be obtained by creating a defect transfer evaluation pattern in which the sizes of the defect correction part and the shape correction correction part are varied, and then performing a transfer test to evaluate the optimum range in advance. And a method of obtaining an optimum range by calculation by lithography simulation. Generally, the widths A and A ′ of the shape correction correction parts 5 and 6 are different depending on the size of the defect correction part and the optical conditions at the time of exposure transfer, but usually 0.02 to 0.1 μm (magnification of 1 ×). If it is within the range of time), A and A ′ may have the same value.

FIG. 1B shows the case where a white defect 8 exists adjacent to the halftone phase shift contact hole pattern 7, and the pattern is the same as that of FIG. 2D. In the conventional repair method, only the defect repair section 9 is repaired, but in the repair method of the present invention, the shape correction repair section 1 is further added.
Add 0 and 11. The width B of the correction portion at this time,
B ′ may be in the range of usually 0.02 to 0.1 μm as in the case of A. The forming method is the same as in the case of FIG.

[0024]

EXAMPLES Next, exposure and transfer were carried out using these modified mask patterns to confirm the effect. FIG. 5 is an example of confirming the effect of the defect repairing method of the present invention. FIG.
FIG. 1A is a diagram showing an exposure transfer result of the pattern shown in FIG. As in the above, the optical conditions during transfer were a wavelength of 365 nm, a numerical aperture of 0.6, and a coherence degree of 0.3, and the transmittance of the halftone phase shift portion of the mask was 8%. Comparing this result with the case of FIG. 4A using the conventional method, it can be seen that the bending deformation of the pattern is obviously improved and the almost original pattern is obtained. Further, when a resist pattern was formed by actually exposing and transferring it on the wafer, a good pattern without pattern deformation was similarly obtained.

Further, in FIG. 7, x2-x2 'of FIG.
A solid line shows a cross-sectional view of the light intensity distribution in the line segment connecting the two. The dotted line shows the light intensity distribution in the case of no defect, but it was almost the same as the solid line. As a result, it was found that the repair method of the present invention was almost equal to the defect-free state, and the repair was complete.

In this example, the light intensity distribution simulation was performed under various conditions as a preliminary experiment, and the pattern was found to be optimal when the width of the shape correction correction portion was 0.04 μm. The shape correction correction unit was set under the conditions. In addition, FIG. 5B is shown in FIG.
It is the figure which similarly calculated | required the exposure transfer result about the pattern shown by. Also in this case, the shape of the transfer pattern is obviously improved as compared with FIG.

In this exposure transfer result, the amount of defocus is set to 0.
And only when. Therefore, in order to see changes in the depth of focus characteristics when the defect correction method according to the present invention is applied, Table 1 shows the exposure transfer pattern dimensions when only the defocus amount is changed in the case of FIG. The change in C (change in size of the exposure transfer image corresponding to the position of the defect correction portion on the mask) is shown. In order to study the effect of the present invention, in the table, there is no defect in the defocus amount under the same conditions (uncorrected, and this is regarded as a “reference value”).
And the size of each exposure transfer pattern when the conventional defect correction method is applied (this is a comparative example).

[0028]

[Table 1]

As is clear from Table 1, in the case of the defect repairing method according to the present invention, a transfer pattern almost equal to that of the original halftone phase shift mask in the case of no defect was obtained. Further, it was found that when the conventional defect repairing method is applied, there is a difference in pattern dimension due to the curved deformation of the pattern.

As described in the section of the prior art, the conventional method of repairing the white defect of the halftone phase shift mask is intended to completely shield only the defective portion, and the original mask pattern. Had been modified to recover. However, since the defect correction portion is a complete light-shielding film, the function of the halftone phase shift mask in the exposure transfer cannot be supplemented even if the original lack of the halftone phase shift portion is graphically supplemented. When actually exposed and transferred using a mask modified by the conventional method,
The obtained pattern shape has a problem that the pattern is curved and deformed as described in the section of the prior art.
Since this phenomenon is caused by the change in the optical proximity effect, it has occurred for all the patterns in the region affected by the proximity effect. That is, in the case of a dense pattern arrangement, not only the pattern in which the defects are in contact but also a plurality of adjacent patterns are curved and deformed.

On the other hand, according to the defect repairing method of the present invention, the halftone phase shift effect of this portion lost by the shaded defect repairing portion is corrected by the shape correction for all patterns affecting the shape. This can be compensated by adding a correction unit for use. That is, along the edge of the original mask pattern, a certain amount (0.0
2 to 0.1 μm), a correction portion is formed so as to have a width of 2 to 0.1 μm, and this is performed on all the adjacent opening patterns.
By correcting the transfer optical image of the portion where these transfer patterns are curved and deformed, a transfer pattern close to the original mask pattern can be obtained.

The present invention is not limited to the above-described embodiment, but can be applied to all kinds of white defect correcting methods in all cases, and of course, the size and width of the shape correcting section are not limited to the above. It is not limited to the example of. Further, the defect repairing method is not limited to the carbon film repairing method using a focused ion beam device,
It can also be applied to a correction method by a lift-off method using a chromium film or other correction methods.

[0033]

When the pattern is exposed and transferred onto the wafer by using the halftone phase shift mask whose mask defect is corrected by the defect correcting method of the present invention, the obtained pattern on the wafer is the same as the halftone phase shift mask. Not only the white defects were not transferred, but there was no pattern deformation due to the lack of the halftone phase shift effect in the defect correction part, dimensional difference, defocusing characteristics, etc., and a very precise and good pattern was obtained.

Further, since the defect repairing method of the present invention can be easily performed by using the defect repairing device used in the prior art, there is no technical problem. Moreover, unlike the conventional case, it is not necessary to accurately position along the pattern edge so that the region of the light shielding film for correction does not protrude from the edge of the halftone phase shift pattern. Since there is no problem even if and are overlapped, there is an advantage that the margin required for the correction position accuracy is relaxed.

After all, with respect to the method of repairing the white defect of the halftone phase shift mask, the defect of the conventional defect repairing method is solved, and the effect can be surely obtained and the process is simple. In particular, it is possible to provide a defect correction method and a halftone phase shift mask that can minimize and correct the influence of a defect correction method on a transfer pattern for a pattern of a dense array to obtain a highly accurate transfer pattern. It was

[Brief description of drawings]

FIG. 1A and FIG. 1B are explanatory views showing an example corrected by a defect correction method of a halftone phase shift mask according to the present invention.

2A to 2D are explanatory diagrams showing examples of typical patterns and types and outlines of white defects in the halftone phase shift mask.

3A to 3D are explanatory diagrams showing an example of a pattern corrected by using a conventional defect correction method.

FIG. 4A to FIG. 4D are diagrams showing transfer patterns when projection exposure transfer is performed using a pattern after the defects of FIG. 3 are corrected by a conventional defect correction method.

5 (a) and 5 (b) are diagrams showing a transfer pattern when projection exposure transfer is performed using the pattern after correction of FIG. 1 by the defect correction method according to the present invention.

FIG. 6 shows x1- of FIG. 4 (a) according to a conventional defect correction method.
It is sectional drawing which shows the light intensity distribution in the line segment shown by x1 '.

FIG. 7 is a cross-sectional view showing a light intensity distribution on a line segment indicated by x2-x2 ′ in FIG. 5A by the defect repairing method according to the present invention.

[Description of sign]

1 ... Partial pattern diagram in halftone phase shift mask 2 ... Halftone phase shift line pattern 3 ... White defect 4 ... Defect correction part 5, 6 ... Shape correction correction part 7 ... ..Halftone phase shift contact hole pattern 8 ... white defects 9 ... defect correction parts 10,11 ... shape correction correction parts p1, p2, p3, p4 ... white defects r1, r2 , R3, r4 ... Defect repair section

Claims (5)

[Claims] 1. A white defect in a halftone phase shift mask comprising a transparent substrate having a pattern having both translucency and phase inversion for transmitted light, when the white defect in the pattern is corrected. A defect-correcting method for a halftone phase shift mask, wherein a light-shielding film is provided so as to completely cover the opening pattern and also partially cover respective ends of a plurality of opening patterns adjacent to the pattern. 2. The defect of the halftone phase shift mask according to claim 1, wherein the shape of the light-shielding film is either a single rectangle or a combination of a plurality of rectangles. How to fix. 3. The defect repairing method for a halftone phase shift mask according to claim 1, wherein the pattern of the light shielding film has symmetry. 4. A halftone phase shift mask provided on a transparent substrate with a pattern having both translucency and phase inversion property for transmitted light, wherein at least a part of the pattern is adjacent to the pattern. A halftone phase shift mask, characterized in that a light-shielding film is provided in a shape that also partially covers the ends of each of the plurality of opening patterns. 5. A halftone phase shift mask, wherein the halftone phase shift mask is repaired by the method for repairing a defect of a halftone phase shift mask according to any one of claims 1 to 3.