KR20080045467A - Photomask having auxiliary pattern and exposure equipment including the same - Google Patents

Abstract

A photomask having auxiliary patterns and exposure equipment having the same are provided to increase margin of a circuit design pattern by aligning a plurality of spot patters as auxiliary pattern within a space between line patterns. A photomask(50) comprises a plurality of first line patterns(32a), a plurality of second line patterns(32b) spaced away from the first line patterns, a space(36) disposed between the first and second line patterns, a plurality of auxiliary patterns formed within the space including a plurality of spot patterns(40'), a plurality of third line patterns(38a) formed on an upper side of the space, and a plurality of fourth line patterns(38b) formed on a lower side of the space. Each of the line patterns comprises a plurality of main patterns that are parallel to each other.

Description

Photomask having auxiliary pattern and exposure equipment including the same}

1 is a plan view illustrating a conventional photomask.

2 is a plan view for explaining a circuit pattern transferred from a conventional photomask.

3 is a plan view illustrating a photomask according to an embodiment of the present invention.

4 is a plan view illustrating a photomask according to another embodiment of the present invention.

5 and 6 are plan views illustrating photomasks according to another exemplary embodiment of the present invention.

7 is a schematic configuration diagram illustrating an exposure apparatus employing a photomask according to the present invention.

8 and 9 are plan views illustrating circuit patterns transferred from the photomasks of FIGS. 3 and 4, respectively.

The present invention relates to an apparatus for manufacturing a semiconductor device, and to a photomask having an auxiliary pattern and an exposure apparatus having the same.

Semiconductor devices are manufactured using unit processes such as photolithography, etching, thin film deposition, and diffusion processes. The photographic process of these unit processes directly affects the formation of fine patterns of the semiconductor device. Therefore, in the fabrication of highly integrated semiconductor devices, the photographic process plays a very important role.

The photolithography may include a coating step of forming a photoresist layer on a semiconductor substrate, an exposure step of selectively irradiating light to a predetermined region of the photoresist film using a photomask, and selectively exposing the exposed photoresist film. And developing to form a photoresist pattern.

In the exposing step, the semiconductor substrate having the photoresist film is aligned with the photo mask, and the photomask is irradiated with light from a light source to transfer the shape of the circuit patterns on the photomask to the photoresist film. By doing so.

In this case, when the critical dimension of the circuit pattern approaches the resolution limit of the exposure equipment that performs the exposure step, the circuit pattern on the photomask and the circuit transferred to the photoresist film. The patterns will be different from each other. For example, optical phenomena such as corner rounding and line end foreshortening are observed from the circuit pattern transferred to the photoresist film. This phenomenon is called the optical proximity effect. The optical proximity effect is known to be due to optical diffraction phenomena in the exposure apparatus, for example a projection system.

As the degree of integration of the semiconductor device increases, the critical dimension of the circuit pattern on the photomask is reduced, and thus the optical proximity effect is remarkably generated. For example, when the circuit patterns on the photomask are arranged in close proximity to each other, the optical proximity effect occurs larger.

1 is a plan view illustrating a conventional photomask. 2 is a plan view for explaining a circuit pattern transferred from a conventional photomask.

Referring to FIG. 1, a circuit design pattern is formed on the photomask 10. The circuit pattern includes first line patterns 12 and second line patterns 14 spaced apart from the first line patterns 12. The first and second line patterns 12 and 14 have a plurality of line patterns that are formed parallel to each other and periodically aligned. A space 16 is positioned between the first and second line patterns 12 and 14. Third line patterns 18 are positioned on the space 16, and fourth line patterns 20 are positioned below the space 16. In this case, the third and fourth line patterns 18 and 20 are disposed to be parallel to the first and second line patterns 12 and 14.

That is, the periodicity of the first line patterns 12 periodically aligned toward the second line patterns 14 is disconnected in the space 16.

A fifth line pattern 22 is formed in the space 16 to be spaced apart from the first to fourth line patterns 12, 14, 18, and 20. That is, the fifth line pattern 22 may be an island type pattern.

Light is irradiated toward the photomask provided with the said circuit pattern. The light irradiated with the photomask passes through the photomask and is then irradiated onto the photoresist film on the wafer. Accordingly, the circuit pattern on the photomask is transferred onto the photoresist film.

Referring to FIG. 2, due to the above-described optical phenomenon, the circuit pattern on the photomask 10 and the circuit pattern transferred on the photoresist film do not coincide with each other. That is, as shown in region A of FIG. 2, the third line patterns 18 ′ transferred onto the photoresist film 24 may include the third line pattern 18 of the photomask 10. In comparison, its width and length are formed short. This phenomenon also occurs in the transferred fourth and fifth line patterns 20 'and 22'.

In addition, as shown in the region B of FIG. 2, the transferred first and second line patterns 12 ′ and 14 ′ are extended in the expanded portion B due to the above-described optical phenomenon. Is formed. In this case, the extension B appears adjacent to the space 16 and is formed towards the space 16. That is, the extended portions of the transferred first and second line patterns 12 ′ and 14 ′ are formed to face each other with the space 16 therebetween.

Accordingly, there is a demand for a photomask capable of improving the resolution by suppressing an optical phenomenon such as the extension B.

An object of the present invention is to provide a photomask having an auxiliary pattern suitable for suppressing an optical proximity effect.

Another object of the present invention is to provide an exposure apparatus having a photomask suitable for suppressing an optical proximity effect.

According to one aspect of the present invention, the present invention provides a photomask having an auxiliary pattern suitable for suppressing the optical proximity effect. The photomask includes first line patterns. Second line patterns spaced apart from the first line patterns are disposed. A space is located between the first and second line patterns. Auxiliary patterns are disposed in the space. Third line patterns are disposed on the space. Fourth line patterns are disposed under the space.

In some embodiments according to an aspect of the present disclosure, each of the first to fourth line patterns may include a plurality of main patterns disposed parallel to each other.

In another embodiment of the present invention, the first and second line patterns may extend to be located at both sides of the third and fourth line patterns.

In another embodiment of the present invention, the auxiliary patterns may include a plurality of spot patterns. In this case, the speckled patterns may be aligned along the extension lines of the line patterns corresponding to each other of the third and fourth line patterns.

In another embodiment of the present invention, the speckled patterns may be formed to have narrower widths than the widths of each of the first to fourth line patterns.

In another embodiment of the present invention, at least one of the first line pattern and at least one of the second line patterns of the second line patterns may include the first line pattern and the second line pattern. The apparatus may further include first extended patterns formed to extend from the pattern. In this case, the first extended patterns of the first line pattern and the first extended patterns of the second line pattern may include a space area between the auxiliary patterns and the third line patterns, and the auxiliary pattern. And a space area between the regions and a space area between the auxiliary patterns and the fourth line patterns.

In another embodiment of the present invention, the third and fourth line patterns may include second extended patterns formed to extend from an end thereof.

In another embodiment of the present invention, the method may further include a fifth line pattern positioned between the first and second line patterns. In this case, the auxiliary patterns may be located between the first line patterns and the fifth line pattern, and between the fifth line pattern and the second line patterns.

In another embodiment of the present invention, the spacing between the first line patterns and the auxiliary patterns is formed to be smaller than the spacing between the auxiliary patterns and the fifth line pattern, and the auxiliary patterns and The interval between the second line patterns may be formed to be smaller than the interval between the fifth line pattern and the auxiliary patterns.

In another embodiment, the auxiliary patterns may be located between the third line patterns and the fifth line pattern, and between the fourth line patterns and the fifth line pattern. In this case, the auxiliary patterns between the third line patterns and the fifth line pattern are aligned along the extension lines of the third line patterns, and the auxiliary pattern between the fourth line patterns and the fifth line pattern. They may be aligned along the extension lines of the fourth line patterns.

In another embodiment of the present invention, the first line patterns, the second line patterns, and the fifth line pattern may be formed in parallel with each other.

According to another aspect of the present invention, the present invention provides an exposure apparatus having a photomask suitable for suppressing the optical proximity effect. The exposure apparatus includes a light source. First line patterns, second line patterns spaced apart from the first line patterns, a space formed between the first and second line patterns, auxiliary patterns disposed in the space, and an upper portion of the space A photomask including third line patterns disposed in the first and fourth line patterns disposed under the space is spaced apart from the light source. A wafer chuck on which the wafer is mounted is disposed spaced apart from the photomask.

In some embodiments according to another aspect of the present invention, each of the first to fourth line patterns may include a plurality of main patterns arranged side by side. In this case, the main patterns may be transferred to the wafer on the wafer chuck by the exposure process and the auxiliary patterns may not be transferred to the wafer.

In another embodiment of the present invention, the first to second line patterns may extend to be located at both sides of the third to fourth line patterns.

In another embodiment of the present invention, the auxiliary patterns may include a plurality of spot patterns. In this case, the speckled patterns may be aligned along the extension lines of the line patterns corresponding to each other of the third and fourth line patterns.

In another embodiment of the present invention, the speckled patterns may be formed to have narrower widths than the widths of each of the first to fourth line patterns.

In another embodiment of the present invention, at least one of the first line pattern and at least one of the second line patterns, the second line pattern is the first line pattern and the second line pattern. It may further include extended patterns formed to extend from the line pattern. In this case, the extended patterns of the first line pattern and the extended patterns of the second line pattern may include a space area between the auxiliary patterns and the third line patterns and a space between the auxiliary patterns. A region may be disposed to correspond to a space region between the auxiliary patterns and the fourth line patterns.

In another embodiment of the present invention, the method may further include a fifth line pattern positioned between the first and second line patterns. In this case, the auxiliary patterns may be located between the first line patterns and the fifth line pattern, and between the fifth line pattern and the second line patterns.

In another embodiment of the present invention, the spacing between the first line patterns and the auxiliary patterns is formed to be smaller than the spacing between the auxiliary patterns and the fifth line pattern, and the auxiliary patterns and The interval between the second line patterns may be formed to be smaller than the interval between the fifth line pattern and the auxiliary patterns.

In another embodiment, the auxiliary patterns may be located between the third line patterns and the fifth line pattern, and between the fourth line patterns and the fifth line pattern. In this case, the auxiliary patterns between the third line patterns and the fifth line pattern are aligned along the extension lines of the third line patterns, and the auxiliary pattern between the fourth line patterns and the fifth line pattern. They may be aligned along the extension lines of the fourth line patterns.

In another embodiment of the present invention, the first line patterns, the second line patterns, and the fifth line pattern may be formed in parallel with each other.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments introduced below are provided to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the present invention may be embodied in other forms without being limited to the embodiments described below. In the drawings, lengths, thicknesses, and the like of layers and regions may be exaggerated for convenience of description. Like numbers refer to like elements throughout the specification.

3 is a plan view illustrating a photomask according to an embodiment of the present invention. 4 is a plan view illustrating a photomask according to another embodiment of the present invention. 5 and 6 are plan views illustrating photomasks according to another exemplary embodiment of the present invention. 7 is a schematic configuration diagram illustrating an exposure apparatus employing a photomask according to the present invention. 8 and 9 are plan views illustrating circuit patterns transferred from the photomasks of FIGS. 3 and 4, respectively.

Referring to FIG. 3, the photomask 30 according to an embodiment of the present invention includes circuit design patterns. The circuit design patterns include first line patterns 32a and second line patterns 32b spaced apart from the first line patterns 32a. The first and second line patterns 32a and 32b may be a plurality of first main line patterns 34 disposed to be spaced apart from each other. Sub-spaces may be located between the first main line patterns 34. The first main line patterns 34 may be arranged parallel to each other with the same width and spacing. That is, the first main line patterns of the first and second line patterns 32a and 32b may be disposed with periodicity. In addition, the first main line patterns 34 may be aligned with the Y axis.

The first main line patterns 34 may be light blocking patterns formed on a transparent substrate. For example, the first main line patterns 34 may be chromium layer patterns deposited on a transparent substrate. The transparent substrate may be transparent quartz.

The transparent substrate may be exposed through the subspaces disposed between the first main line patterns 34.

A space 36 having a predetermined width is positioned between the first and second line patterns 32a and 32b. Line patterns are not formed in the space 36. Therefore, the periodicity of the first and second line patterns 32a and 32b may be disconnected by the space 36.

In this case, the first main line patterns 34 adjacent to the space 36 may have first extension patterns 42a extending toward the space 36. The first extension patterns 42a are selectively formed on the main line patterns 34 in correspondence to the interval between the third and fourth line patterns described later, that is, the length of the space in the Y-axis direction. It can be formed as. In addition, the first extension patterns 42a may be formed alternately and repeatedly with patterns having different widths.

Third line patterns 38a are positioned on the space 36. Similarly, fourth line patterns 38b are disposed under the space 36. The third and fourth line patterns 38a and 38b may be a plurality of second main line patterns 39 disposed parallel to each other. The second main line patterns 39 may have the same width L1 and may be spaced apart from each other. In this case, the second main line patterns of the fourth line patterns 38b may be aligned to correspond to the second main line patterns of the third line patterns 38a. That is, the second main line patterns of the third and fourth line patterns 38a and 38b corresponding to each other may be positioned to face each other with a space therebetween. In this case, the second main line patterns 39 may be aligned to be parallel to the Y axis.

The second main line patterns 39 may also be light blocking patterns formed on the transparent substrate. Subspaces exposing the transparent substrate may be disposed between the second main line patterns 39.

The first and second line patterns 32a and 32b may be arranged in parallel with the third and fourth line patterns 38a and 38b. In addition, the first and second line patterns 32a and 32b may be formed to extend along a length direction of the first and second line patterns 32a and 32b, and may be disposed on both sides of the third and fourth line patterns 38a and 38b.

On the other hand, auxiliary patterns are disposed in the space 36. When the photomask 30 is irradiated with light to transfer the circuit design patterns of the photomask onto the photoresist film on the wafer, the first and second main line patterns 34 and 39 are formed in the photoresist. Transferred on the film, and the auxiliary patterns are not transferred on the photoresist film. That is, the auxiliary patterns may serve as dummy patterns. In addition, the auxiliary patterns may serve as an optical diffraction grating. Accordingly, the auxiliary patterns may serve to compensate for optical phenomena according to the first and second main line patterns 34 and 39.

The auxiliary patterns may also be light blocking patterns formed on the transparent substrate.

The auxiliary patterns may be a plurality of spot patterns 40. The specular patterns 40 may be formed to have the same area. When the auxiliary patterns are the specular patterns 40, the auxiliary patterns may be square patterns. The speckled patterns 40 may be spaced apart from each other with the same widths. The speckled patterns 40 may be located parallel to each other with the same spacing. That is, the speckled patterns 40 may be aligned in the space 36 along the extension lines of the third and fourth line patterns 38a and 38b disposed to face each other. Accordingly, the space 36 may be divided by the spot patterns 40. In this case, the number of spot patterns aligned parallel to the X axis may be determined according to the number of second main line patterns of the third line patterns 38a or the fourth line patterns 38b. Can be. In this case, the spot patterns aligned with the X axis may be a plurality of patterns for one second main line patterns.

Preferably, the width L2 of the specular patterns 40 is smaller than the width L1 of the second main line patterns 39 of the third and fourth line patterns 38a and 38b. . In this case, the speckled patterns 40 extend from the center of the third and fourth line patterns 38a and 38b disposed to face each other, and have an extension line parallel to the Y axis positioned in the space 36. It is preferred to align accordingly. In addition, the width of the speckled patterns 40 may be smaller than the width of the first main line patterns 34. When the width of the specular patterns 40 is formed larger than the first and second main line patterns 34 and 39, the specular patterns 40 are formed on the photoresist film after the exposure process. May appear as afterimages. Therefore, the width of the specular patterns 40 may be determined according to the widths of the first and second main line patterns 34 and 39. In addition, the number of spot patterns aligned with the Y axis may be determined according to the widths of the first and second main line patterns 34 and 39.

Spot patterns aligned with the Y axis may be formed in a single unitary pattern. That is, the auxiliary pattern aligned with the Y axis may be a bar type pattern. In this case, in order to suppress the optical proximity effect generated by the exposure process, the bar pattern should have a very small width compared to the spot pattern. For example, when the width of the first and second main line patterns 34 and 39 is about 65 nm, the optical proximity effect is suppressed when the width of the spot patterns 40 is about 65 nm or less. can do. On the other hand, when the width of the first and second main line patterns 34 and 39 is about 65 nm, the optical proximity effect may be suppressed when the width of the bar pattern is about 35 nm or less.

In addition, when using a scattering bar type pattern as an auxiliary pattern, the scattering bar pattern has a minimum length in order to suppress an optical proximity effect or suppress a residual occurring on the photoresist. Has the disadvantage of requiring

Therefore, when the degree of integration of the semiconductor device is increased and the design rule is reduced, the speckle pattern is more preferable to suppress the optical proximity effect or to suppress the afterimage on the photoresist than the bar pattern. That is, in improving the resolution according to the exposure process, the spot pattern is more preferable than the bar pattern as the auxiliary pattern. In the case where the specular patterns are used as auxiliary patterns, the specular patterns are not related to the resolution of the pattern, but an optical field such as an interference phenomenon caused by the specular patterns is described above. It acts as an auxiliary pattern.

Meanwhile, when the specular patterns 40 are disposed in the space 36, the first main line patterns adjacent to the space 36 may be the first surfaces of the first main line patterns 34. It is preferable to have the second expansion patterns 42b extending from the toward the space 36. The second extension patterns 42b may be located at both sides of the first extension patterns 42a. The second extension patterns 42b serve as dummy patterns not transferred onto the photoresist during the exposure process.

In addition, third extension patterns 42c are formed to extend from the first main line patterns 34 on second surfaces facing the first surfaces of the first main line patterns 34. Can be. The third extension patterns 42c may be formed alternately and repeatedly with patterns having different widths. For example, third extension patterns corresponding to the specular patterns aligned along the X axis may be formed to have thicker widths than third extension patterns corresponding to the spaces between the specular patterns 41.

In addition, the third extension patterns 42c may be formed to have smaller widths than the second extension patterns 42b. The third extension patterns 42c may serve as dummy patterns not transferred onto the photoresist during the exposure process.

The second and third extension patterns 42b and 42c may serve to generate an optical diffraction phenomenon according to an exposure process. That is, the second and third extension patterns 42b and 42c may serve to suppress the optical proximity effect.

Meanwhile, the widths of the first extension patterns 42a may be formed in inverse proportion to the distance between the first main line patterns 34 and the space 36. For example, the width of the first extension patterns of the first main line patterns located close to the space 36 is greater than the width of the first extension patterns of the first main line patterns located far from the space 36. Can be.

In addition, the width of the first extension patterns 42a may be determined according to the width of the first and second main line patterns 34 and 39 and the width of the space 36.

As described above, since the spot pattern 40 may have a larger width than the bar pattern, when the spot patterns 40 are used as the auxiliary patterns, the first expansion may be performed. The width of the patterns 42a can be reduced. That is, the distance between the first extension patterns 42a and the first main line pattern adjacent to the first extension patterns 42a may be increased. Accordingly, the pattern margin of the first main line patterns may be improved.

Hereinafter, a photomask according to another embodiment of the present invention will be described.

Referring to FIG. 4, a photomask according to another embodiment of the present invention is similar to the photomask according to the embodiment of the present invention described above. That is, the photomask 50 according to another embodiment of the present invention includes the first to fourth line patterns 32a, 32b, 38a, and 38b and the space 36 described above. Therefore, the description of the first to fourth line patterns 32a, 32b, 38a, and 38b and the above-described space 36 will be omitted.

Referring to FIG. 4, the photomask 50 according to another embodiment of the present invention includes a fifth line pattern 52 disposed in the space 36. The fifth line pattern 52 may be disposed in an island type in the space 36. The fifth line pattern 52 may have a central portion thereof larger than a width of both ends. Accordingly, when the photolithography process is performed using the photomask having the fifth line pattern, a pattern having a contact region at the center thereof may be provided.

The fifth line pattern 52 may be disposed in parallel with the first and second main line patterns 34 and 39 described above. That is, the fifth line pattern 52 may be disposed parallel to the Y axis. The fifth line pattern 52 may be a light blocking pattern such as a chrome layer pattern.

Auxiliary patterns such as spot patterns are positioned between the first main line patterns 34 of the first and second line patterns 32a and 32b and the fifth line pattern 52. In this case, the speckled patterns can be aligned side by side with the Y axis. Since the width and number of the specular patterns are the same as described above, description thereof will be omitted.

Among the spot patterns aligned with the Y axis, the spot patterns 40 'disposed between the first line patterns 32a and the fifth line pattern 52 may include the fifth line pattern ( 52 may be disposed closer to the first line patterns 32a than to the first line patterns 32a. That is, when the fifth line pattern 52 is located at the center of the space 36, the distance L4 between the first line pattern 32a and the speckled patterns 40 ′ is equal to the above. It may be smaller than the spacing L5 between the speckled patterns 40 ′ and the fifth line pattern 52.

Similarly, among the spot patterns aligned with the Y axis, the spot patterns 40 'disposed between the second line patterns 32b and the fifth line pattern 52 may be formed in the fifth pattern. The line pattern 52 may be disposed closer to the second line patterns 32b. That is, when the fifth line pattern 52 is located at the center of the space 36, the spacing between the second line pattern 32b and the spot patterns 40 ′ is the spot pattern. It may be smaller than the spacing between the 40 and the fifth line pattern 52.

Accordingly, the above-described optical proximity effect can be greatly suppressed by aligning the spot patterns 40 'closer to the first and second line patterns 32a and 32b which require more periodicity.

Further, the spot patterns 40 ″ are disposed in the space 36 and disposed above and below the fifth line pattern 52, and are aligned between the first and second line patterns 32a and 32b. In this case, the speckled patterns 40 ″ may be formed when the fifth line pattern 52 does not exist in the space 36, that is, the specular patterns according to the above-described embodiment. It is preferable to arrange the same. For example, an extension line extending along the Y axis from the fifth line pattern 52 and the gap L6 between the first main line patterns 34 and the speckle patterns 40 ″ and the spots The spacing L7 between the pattern patterns 40 "may be equal to each other. That is, the speckle patterns 40 ″ may be aligned in the space 36 along the extension lines of the second main line patterns 39 facing each other.

Meanwhile, when the fifth line pattern 52 is disposed in the space 36 and the specular patterns are arranged as an auxiliary pattern, the fifth line pattern 52 is the fifth line pattern 52. The fourth extension patterns 42d may extend from the fourth extension patterns 42d. The fourth extension patterns 42d may be spaced apart from each other. In addition, the fourth extension patterns 42d may be patterns having different widths from each other. For example, fourth extension patterns positioned at the center of the fifth line pattern 52 may have thicker widths than fourth extension patterns positioned at both ends of the fifth line pattern 52. have.

In addition, when the fifth line pattern 52 is disposed in the space 36 and the specular patterns are arranged in the auxiliary pattern, the first main line patterns adjacent to the space 36 may have the same amount. The fifth extension patterns 42e may be provided on the surfaces. The fifth extension patterns 42e may have different widths corresponding to the positions of the speckle patterns in the space 36. In particular, fifth extension patterns formed on the first surface of the first main line patterns 34 adjacent to the space 36 are formed on the second surface of the first main line patterns opposite the first surface. It may be formed to have widths larger than the widths of the fifth extension patterns.

In addition, when the fifth line pattern 52 is disposed in the space 36 and the specular patterns are arranged as an auxiliary pattern, the second main line patterns 39 may be disposed in the space 36. Sixth extension patterns 42f may be provided on end portions of the adjacent second main line patterns 39.

The fourth to sixth extension patterns 42d, 42e, and 42f serve as dummy patterns not transferred onto the photoresist during the exposure process.

Alternatively, referring to FIG. 5, the distance between the third line patterns 38a and the fifth line pattern 52 may be between the fourth line patterns 38b and the fifth line pattern 52. When the spot patterns are disposed in the space, the fourth expansion patterns 42d may be formed at positions between the center portion and the end portion of the fifth line pattern 52.

As another method, referring to FIG. 6, a plurality of fifth line patterns described with reference to FIG. 4 may be disposed in a space.

Hereinafter, an exposure apparatus having the above-described photomask as a third embodiment of the present invention will be described.

Referring to FIG. 7, the exposure apparatus includes a light source 60 for irradiating light and a photomask 62 spaced apart from the light source 60. Since the photomask 62 is the same as the photomask having the circuit design patterns and the auxiliary patterns described above, a description thereof will be omitted.

A masking blade 64 may be disposed between the light source 60 and the photomask 62. The masking blade 64 may serve to define an irradiation area of light irradiated from the light source 60 to the photomask 62.

The wafer stage 66 and the wafer chuck 68 on the wafer stage 66 are disposed at a position spaced apart from the photomask 62. The wafer chuck 68 serves to support the wafer 70. An optical system 72 may be disposed between the wafer chuck 68 and the photomask 62 on which the wafer 70 is seated. The optical system 72 serves to reduce and project the light passing through the photomask 62 onto the wafer chuck 68. Light incident on the wafer chuck 68 is irradiated onto the photoresist film on the wafer 70 to form photoresist patterns on the wafer 70.

As a result of performing an exposure process using an exposure apparatus having a photomask of FIGS. 3 and 4, the photoresist patterns formed on the photoresist films 80 and 82 are shown in FIGS. 8 and 9. Reference numeral 90 in FIG. 9 denotes a contact area. 8 and 9, the problems of the prior art, that is, the areas A and B of FIG. 2 are improved. The results shown in FIGS. 8 and 9 may be confirmed through simulation (SOLID_E simulation).

As described above, according to the present invention, the optical proximity effect according to the exposure process may be suppressed by aligning auxiliary patterns such as spot patterns in a space located between line patterns of the photomask. In particular, since the speckle pattern can be formed to have a size corresponding to the size of the design rule, the resolution can be improved by suppressing the optical proximity effect more than the auxiliary patterns such as the bar pattern.

In addition, since the optical proximity effect can be suppressed by forming spot patterns having a larger width than the bar pattern as the auxiliary pattern, the margin of the circuit design pattern can be improved.

Claims (21)

First line patterns; Second line patterns spaced apart from the first line patterns; A space located between the first and second line patterns; Auxiliary patterns disposed in the space; Third line patterns disposed on the space; And And a fourth line pattern disposed under the space. The method of claim 1, Each of the first to fourth line patterns may include a plurality of main patterns disposed parallel to each other. The method of claim 1, And the first and second line patterns extend to be positioned at both sides of the third and fourth line patterns. The method of claim 1, The auxiliary patterns may include a plurality of spot patterns, wherein the spot patterns are aligned along extension lines of line patterns corresponding to each other among the third and fourth line patterns. . The method of claim 4, wherein The specular pattern is formed to have a width narrower than the width of each of the first to fourth line patterns. The method of claim 1, The first line pattern of at least one of the first line patterns and the second line pattern of at least one of the second line patterns may be formed to extend from the first line pattern and the second line pattern. And first extended patterns of the first line pattern, and the first extended patterns of the second line pattern, the auxiliary patterns and the third line patterns. And a space area therebetween, a space area between the auxiliary patterns, and a space area between the auxiliary patterns and the fourth line patterns. The method of claim 1, And the third and fourth line patterns include second extended patterns formed to extend from an end thereof. The method of claim 1, And further including a fifth line pattern positioned between the first and second line patterns, between the first line patterns and the fifth line pattern, and between the fifth line pattern and the second line patterns. A photomask, characterized in that the auxiliary patterns are located between. The method of claim 8, The interval between the first line patterns and the auxiliary patterns is smaller than the interval between the auxiliary patterns and the fifth line pattern, and the interval between the auxiliary patterns and the second line patterns is The photomask of claim 5, wherein the photomask is formed to be smaller than an interval between the fifth line pattern and the auxiliary patterns. The method of claim 8, The auxiliary patterns are positioned between the third line patterns and the fifth line pattern, and between the fourth line patterns and the fifth line pattern, and between the third line patterns and the fifth line pattern. Wherein the auxiliary patterns of are aligned along extension lines of the third line patterns, and the auxiliary patterns between the fourth line patterns and the fifth line pattern are aligned along extension lines of the fourth line patterns. Mask. The method of claim 8, And the first line patterns, the second line patterns, and the fifth line pattern are formed parallel to each other. Light source; A first line pattern spaced apart from the light source, second line patterns spaced apart from the first line patterns, a space formed between the first and second line patterns, and disposed in the space A photomask having auxiliary patterns, third line patterns disposed above the space, and fourth line patterns disposed below the space; And And a wafer chuck disposed to be spaced apart from the photomask and on which the wafer is mounted. The method of claim 12, Each of the first to fourth line patterns includes a plurality of main patterns arranged side by side, wherein the main patterns are transferred to a wafer on the wafer chuck by an exposure process and the auxiliary patterns Exposure equipment characterized in that it is not transferred to the wafer. The method of claim 12, And the first to second line patterns extend on both sides of the third to fourth line patterns. The method of claim 12, The auxiliary patterns may include a plurality of spot patterns, wherein the spot patterns are aligned along extension lines of line patterns corresponding to each other among the third and fourth line patterns. . The method of claim 15, And the speckle pattern is formed to have widths narrower than the width of each of the first to fourth line patterns. The method of claim 12, An extended pattern formed to extend from the first line pattern and the second line pattern at least one of the first line pattern and at least one second line pattern of the second line patterns Further including extended patterns, wherein the extended patterns of the first line pattern and the extended patterns of the second line pattern are space regions between the auxiliary patterns and the third line patterns, the And a space area between the auxiliary patterns and a space area between the auxiliary patterns and the fourth line patterns. The method of claim 12, And further including a fifth line pattern positioned between the first and second line patterns, between the first line patterns and the fifth line pattern, and between the fifth line pattern and the second line patterns. Exposure equipment, characterized in that the auxiliary patterns are located between. The method of claim 18, The interval between the first line patterns and the auxiliary patterns is smaller than the interval between the auxiliary patterns and the fifth line pattern, and the interval between the auxiliary patterns and the second line patterns is Exposure apparatus, characterized in that formed to be smaller than the interval between the fifth line pattern and the auxiliary pattern. The method of claim 18, The auxiliary patterns are positioned between the third line patterns and the fifth line pattern, and between the fourth line patterns and the fifth line pattern, and between the third line patterns and the fifth line pattern. Wherein the auxiliary patterns of are aligned along the extension lines of the third line patterns, and the auxiliary patterns between the fourth line patterns and the fifth line pattern are aligned along the extension lines of the fourth line patterns. equipment. The method of claim 18, And the first line patterns, the second line patterns, and the fifth line pattern are formed parallel to each other.

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