JP2002365783A - Apparatus of forming mask pattern, apparatus and method of manufacturing high-resolution mask as well as method of forming resist pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus of forming mask patterns which is capable of improving pattern shape controllability and transfer position accuracy by preventing the occurrence of deviations in phase differences and the reduction in the depth of focus and the allowance of the exposure energy in exposure in consequence of the nonuniformity in the pattern shapes and pattern density of the mask patterns in forming a high-resolution mask, an apparatus and method of manufacturing the high-resolution pattern as well as a method of forming resist patterns. SOLUTION: This apparatus is provided with a first mask pattern forming section 21 which forms the initial mask pattern in accordance with prescribed pattern data, a pattern dividing section 22 which divides the initial mask pattern to plural kinds of the mask patterns on the basis of the pattern shape and pattern density of the fine patterns in accordance with the data relating to a loading effect with respect to the initial mask pattern and a second mask pattern forming section 24 which forms the plural final mask patterns by each of plural kinds of the mask patterns.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a mask pattern, an apparatus and a method for manufacturing a high-resolution mask, and a method for forming a resist pattern, and more particularly to a high-resolution mask used in a photolithography process for manufacturing a semiconductor device. The present invention relates to an apparatus for forming a mask pattern of a mask, an apparatus and a method for manufacturing a high-resolution mask on which the mask pattern is drawn, and a resist pattern forming method for forming a fine resist pattern using the high-resolution mask.

[0002]

2. Description of the Related Art IC (Integrated Circuit)
In a photolithography process in a semiconductor device manufacturing process such as that described above, high resolution exceeding a resolution limit determined from an exposure wavelength is required as a pattern becomes finer. In recent years, as a technique for forming a fine pattern having a wavelength equal to or less than the exposure wavelength in response to such a demand, a phase shift mask that obtains high resolution by utilizing a phase difference of light has been used.

The phase shift mask is, for example, a halftone type using a material that slightly transmits light as a light shielding film, or a Levenson that inverts a phase in a fine pattern in both sides in a fine line width direction in a periodic pattern. A pattern, an auxiliary pattern type that arranges a phase inversion pattern around the original pattern, an edge emphasis type that inverts the phase at the edge of the pattern, and a chromeless type that inverts the phase only by changing the thickness of the substrate There is. Here, DR
AM (Dynamic Random Access Memory) and high-speed LSI
A description will be given of a Levenson phase shift mask that has already been put to practical use in a manufacturing process such as (Large Scale Integration).

In a conventional Levenson phase shift mask, as shown in FIGS. 9A to 9D, light-shielding films 91a, 91b and 91c patterned in a predetermined shape are formed on a transparent quartz substrate 90. Is formed periodically,
The region sandwiched between the light-shielding films 91a, 91b, and 91c is a transmitting portion that transmits exposure light. As a method of inverting the phase of the exposure light transmitted through the adjacent transmission part, for example, a substrate digging type in which the quartz substrate 90 in the adjacent transmission part is dug (see FIGS. 9A and 9B) Or a phase shifter providing type in which a phase shifter having a predetermined refractive index and a predetermined thickness is provided to one of the transmission portions (FIG. 9).
(C) and (d)).

Then, the light-shielding film 91 is formed in the substrate digging type.
For example, a single trench (Single T) in which an excavation 92 is formed in only one of the transmissive portions sandwiched between the light shielding films 91a and 91b in the adjacent transmissive portion sandwiched between the a, 91b and 91c.
(Rench) type (see FIG. 9A) and the light shielding films 91a and 91a.
There is a dual trench type (see FIG. 9A) in which diggings 93 and 94 having different depths are respectively formed in adjacent transmission portions sandwiched between b and 91c. Also,
The phase shifter-attached type also has a light shielding film 91 on a quartz substrate 90.
a, 91b, and 91c, for example, the light shielding film 91
b, 91c, the phase shifter 9
5 (see FIG. 9 (c))
Alternatively, after the phase shifter 96 is formed on the quartz substrate 90, the light shielding films 91a, 91b, and 91c are formed on the phase shifter 96, and the light shielding films 91a, 91b, and 91c in the adjacent transmission portions are further formed.
a, a phase shifter 9 having only one transmission portion sandwiched between 91b
6 (see FIG. 9D). Among such Levenson phase shift masks, the substrate digging type Levenson phase shift mask having a dual trench structure shown in FIG.

[0006]

However, for example, DRA
When fabricating a dual-trench structure Levenson phase shift mask of a dual trench structure used in a process of manufacturing a logic circuit mixed with M, a logic circuit portion (hereinafter simply referred to as a “logic portion”) and a DRAM
Since there is a large difference in pattern shape and pattern density between the portions, a problem arises in that it is not possible to form a digging to produce a desired phase difference.

That is, as shown in FIG. 10, when forming a gate pattern having a gate length of 0.10 μm, for example, in a logic portion and a DRAM portion, light-shielding films 91a, 91b, 91c are formed in the logic portion on the quartz substrate 90. When the light shielding films 91d, 91e,..., 91g are formed in the DRAM portion, and the quartz substrate 90 of the transmission portion sandwiched between these light shielding films 91a, 91b,. In addition, for example, a logic part whose gate pattern is represented by an isolated pattern and an L & S (line and
Since there is a great difference in pattern shape and pattern density from a DRAM portion typified by a (space) pattern, a loading effect in which the digging depth by etching is different due to the difference occurs.

As a result, in the DRAM part having a high pattern density, a 380 nm deep dug 93b and a depth of 380 nm + 230 nm = 610 nm are formed in the adjacent transmission part.
Diggings 94b are respectively formed, and the desired phase difference 1
In the logic part having a low pattern density, which generates 71 °, a digging 93a having a depth of 400 nm and a depth of 400 nm + 250 nm = 650 are formed in the adjacent transmission part.
An indentation 94b of nm is formed, and a phase difference 186 ° deviated from a desired phase difference is generated.
Such a deviation of the phase difference not only causes a difference in pattern line width when forming a resist pattern using the phase shift mask, but also causes a placement error in which the pattern deviates from a desired position. Cause.

In FIG. 10, a case is assumed in which an exposure machine having a projection magnification of 4 times is used, and therefore, a DRAM is used.
, 91, L & S pattern light shielding films 91d, 91e,.
The width of g is 100 × 4 nm, and the transmission portion is dug 93
The width of b, 94b is 240 × 4 nm. On the other hand, in the logic section, the logic section and the DR
Since the mask bias by optical proximity correction (Optical Proximity Correction) is applied in order to make the optimal exposure amount of the AM portion coincide, the width of the light shielding film 91b of the isolated pattern is 90 × 4 nm, and the transparent portion is dug. 9
The width of 3a and 94a is 240 × 4 nm. It is possible to apply the optical proximity effect correction for correcting the deviation of the finished pattern shape using a mask to a high-speed LSI pattern. Depending on the density, there is a place where the correction amount becomes large, so that the problem of reducing the lithography process margin remains.

Further, when an exposure process is performed using a phase difference shift mask as shown in FIG. 10 and light intensity simulation is performed on line width controllability when a fine resist pattern is formed, a graph of FIG. 11 is obtained. As shown. That is, the gate length of the logic section and the DRAM section is set to 0.
Assuming that the specification of the resist transfer line width for the gate pattern of 10 μm is 0.10 ± 0.01 μm, the line width specification boundary line of the logic portion becomes as shown by the solid line in the graph of FIG. The width specification boundary line is indicated by a broken line.

In this case, an ED (Exposure Def) comprising the latitude of the exposure amount and the depth of focus (Depth of Focus).
ocus) When a window is obtained, since both mask patterns of the logic section and the DRAM section are formed on one phase shift mask, both conditions need to be overlapped in the simultaneous exposure. This is the area shaded in the figure. In other words, the ED window common to the logic section and the DRAM section is very small, so that the latitude of the exposure amount is 5.3% and the latitude of the depth of focus is 0.4 μm. The margin of depth of focus is also very small. Therefore, there is a problem that the lithography process margin when forming a fine resist pattern is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when a high resolution mask is formed, a phase shift mask is formed due to the non-uniform pattern shape and pattern density of the mask pattern. In order to prevent the depth of the digging formed by etching the adjacent transmissive part in the fluctuating phase shift, or to reduce the depth of focus and the exposure tolerance during exposure. An object of the present invention is to provide a mask pattern forming apparatus, a high-resolution mask manufacturing apparatus and a manufacturing method, and a resist pattern forming method using a high-resolution mask, which can improve pattern shape controllability and transfer position accuracy. I do.

[0013]

The above objects can be attained by a mask pattern forming apparatus, a high resolution mask forming apparatus and method, and a resist pattern forming method using a high resolution mask according to the present invention described below. You.
That is, the mask pattern forming apparatus according to claim 1 is a mask pattern forming apparatus for a high-resolution mask that improves resolution by using an interference effect due to a phase difference of light passing through both sides of the fine pattern in the fine line width direction. A pattern data input unit for inputting predetermined pattern data; a loading data input unit for inputting data relating to a loading effect when etching a transparent portion of the transparent substrate in the phase shift mask to form a digging; A first mask pattern creating section for creating an initial mask pattern based on the predetermined pattern data input to the input section, and the initial mask pattern created in the first mask pattern creating section are input to the loading data input section. Pattern shape based on loading effect data A pattern division unit for dividing a plurality of types of mask patterns fine pattern density as a reference, a plurality of types of each mask pattern is divided in the pattern division unit section, the create multiple final mask pattern 2
And a mask pattern creating section.

Thus, in the mask pattern creating apparatus according to the first aspect, a first mask pattern creating section for creating an initial mask pattern based on predetermined pattern data, and a phase shift mask for the initial mask pattern A pattern dividing unit that divides into a plurality of types of mask patterns based on a pattern shape and a pattern density based on data on a loading effect when etching a transparent portion of a transparent substrate in forming a digging, and a pattern dividing unit And a second mask pattern creation unit that creates a plurality of final mask patterns for each of the plurality of types of mask patterns divided in
A mask pattern having a pattern shape and a pattern density substantially similar to each other so as not to cause a loading effect is extracted from the initial mask pattern, and a plurality of final mask patterns divided and arranged for each are created. For this reason, when fabricating each of a plurality of phase shift masks for forming a one-layer resist pattern corresponding to the plurality of final mask patterns, the transparent portion of the transparent substrate is etched and dug. At the time of formation, the occurrence of a loading effect due to the difference between the pattern shape and the pattern density is prevented, and digging to a desired depth is formed with high accuracy. Therefore, a plurality of phase shift masks, each of which can control the phase difference with high precision, is realized.

According to a second aspect of the present invention, there is provided an apparatus for creating a mask pattern for a high-resolution mask, comprising: a pattern data input section for inputting predetermined pattern data; Depth of focus and exposure tolerance data input unit for inputting data on exposure tolerance, and first mask pattern generation unit for initially generating a mask pattern based on predetermined pattern data input to the pattern data input unit And a pattern shape and a pattern density of the initial mask pattern created by the first mask pattern creation unit, based on the data on the depth of focus and the exposure latitude input to the depth of focus and exposure latitude data input unit. A pattern dividing section for dividing into a plurality of types of mask patterns based on Divided for each plurality of types of mask patterns, and having a second mask pattern creating section that creates a plurality of final mask pattern.

Thus, in the mask pattern creating apparatus according to the second aspect, a first mask pattern creating section for creating an initial mask pattern based on predetermined pattern data, A pattern dividing unit that divides the pattern into a plurality of types of mask patterns based on the pattern shape and the pattern density based on the data regarding the depth of focus and the latitude of the exposure amount; The second to create a plurality of final mask patterns
By extracting a mask pattern having a similar pattern shape and pattern density enough to ensure a sufficient depth of focus and a sufficient amount of exposure during exposure by having the Thus, a plurality of final mask patterns divided and arranged respectively are created. For this reason,
In the case of forming a one-layer resist pattern by performing multiple exposure processing using a plurality of high-resolution masks manufactured in correspondence with the plurality of final mask patterns, a sufficient focus is required for each of the multiple exposure processing. The depth and the latitude of the exposure amount are secured. Therefore, a high-resolution mask capable of easily securing the optimum exposure conditions and increasing the lithography process latitude is realized.

In the mask pattern forming apparatus according to the second aspect, the plurality of final mask patterns formed in the second mask pattern forming section are each positioned at the position of light passing through both sides of the fine pattern in the fine line width direction. It is preferable to use a phase shift mask pattern that improves the resolving power by using the interference effect due to the phase difference.

That is, the mask pattern forming apparatus according to the second aspect is not limited to a phase shift mask pattern forming apparatus, but can be used when forming a phase shift mask pattern. . In such a case, a plurality of phase shift masks are produced corresponding to a plurality of final mask patterns produced by using the mask pattern producing apparatus, and a multiple exposure process is performed using the plurality of phase shift masks. In this case, a sufficient depth of focus and a sufficient amount of exposure are ensured, and a high-resolution mask capable of easily securing optimum exposure conditions and increasing the lithography process latitude is realized.

A high-resolution mask manufacturing apparatus according to a fourth aspect of the present invention is a high-resolution mask manufacturing apparatus that improves resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction. A pattern data input unit for inputting predetermined pattern data; a loading data input unit for inputting data relating to a loading effect when a transparent portion of the transparent substrate in the phase shift mask is etched to form a digging; A first mask pattern creating unit for creating an initial mask pattern based on the predetermined pattern data input to the input unit, and the initial mask pattern created by the first mask pattern creating unit are input to the loading data input unit. Based on the loading effect data, the pattern shape and pattern A pattern dividing unit for dividing into a plurality of types of mask patterns based on the pattern density, a second mask pattern creating unit for creating a plurality of final mask patterns for each of the plurality of types of mask patterns divided by the pattern dividing unit. And a phase shift mask producing section for producing a plurality of phase shift masks for each of the plurality of final mask patterns produced by the second mask pattern producing section.

In the apparatus for manufacturing a high-resolution mask according to the fourth aspect of the present invention, the apparatus for generating a mask pattern according to the first aspect and a plurality of phase shift masks for each of a plurality of final mask patterns created there. And a mask pattern having a substantially similar pattern shape and pattern density that does not cause a loading effect by extracting a mask pattern from the initial mask pattern and arranging the mask pattern in each of a plurality of final mask patterns. And
A plurality of phase shift masks for forming a one-layer resist pattern are produced corresponding to the plurality of final mask patterns. Therefore, when manufacturing each of the plurality of phase shift masks, when a transparent portion of the transparent substrate is etched to form a digging, a loading effect due to a difference in pattern shape and pattern density occurs. As a result, the digging of the desired depth is accurately formed. Accordingly, high-precision phase difference control of the Levenson phase shift mask is facilitated and the production yield is improved, so that a high-performance Levenson phase shift mask is manufactured at low cost.

According to a fifth aspect of the present invention, there is provided an apparatus for manufacturing a high-resolution mask, comprising: a pattern data input section for inputting predetermined pattern data; and a focal depth for inputting data relating to the depth of focus and the amount of exposure during exposure. A first mask pattern creation unit for initially creating a mask pattern based on predetermined pattern data input to the pattern data input unit; and a first mask pattern creation unit. For the initial mask pattern, the pattern to be divided into a plurality of types of mask patterns based on the pattern shape and the pattern density based on the data on the depth of focus and the latitude of the exposure amount input to the depth of focus and the latitude of the exposure amount input to the tolerance data input unit. For each of the plurality of types of mask patterns divided by the dividing unit and the pattern dividing unit, A second mask pattern creating section that creates a disk pattern, for each of the plurality of final mask pattern created in the second mask pattern creation section, and a high-resolution mask making unit for making a plurality higher resolution mask,
It is characterized by having.

In the apparatus for manufacturing a high-resolution mask according to the fifth aspect, a plurality of high-resolution masks are prepared for each of the plurality of final mask patterns generated by the apparatus for generating a mask pattern according to the second aspect. By having a high-resolution mask manufacturing section to be manufactured, a mask pattern having a substantially similar pattern shape and pattern density enough to secure a sufficient depth of focus and a sufficient exposure amount at the time of exposure is extracted from the initial mask pattern. Then, a plurality of high-resolution masks for forming a one-layer resist pattern can be manufactured corresponding to the plurality of final mask patterns. For this reason, when performing multiple exposure processing using these plural high-resolution masks to form a resist pattern of one layer, a sufficient depth of focus and a sufficient amount of exposure are required for the multiple exposure processing. Secured. Therefore, a high-resolution mask capable of easily securing the optimum exposure condition and increasing the lithography process latitude is manufactured.

In the apparatus for manufacturing a high-resolution mask according to the fifth aspect, the plurality of high-resolution masks manufactured in the mask manufacturing section are each provided with a phase difference of light transmitted through both sides of the fine pattern in the fine line width direction. It is preferable to use a phase shift mask that improves the resolving power by using the interference effect of (6).

That is, the apparatus for manufacturing a high-resolution mask according to claim 5 is not limited to the apparatus for manufacturing a phase shift mask, but can also be used when manufacturing a phase shift mask. In that case, when performing multiple exposure processing using a plurality of phase shift masks manufactured using the high-resolution mask manufacturing apparatus, sufficient depth of focus and sufficient exposure amount are secured, respectively. At the same time, it becomes possible to set optimal optical conditions for each exposure. Therefore, a high-resolution mask capable of easily securing the optimum exposure condition and increasing the lithography process latitude is manufactured.

According to a seventh aspect of the present invention, there is provided a method for manufacturing a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction. A step of creating an initial mask pattern based on predetermined pattern data; and, based on the initial mask pattern, data on a loading effect when etching a transparent portion of a transparent substrate in a phase shift mask to form a digging. ,
Dividing a plurality of types of mask patterns based on the pattern shape and the pattern density; creating a plurality of final mask patterns for each of the plurality of types of mask patterns; Forming a shift mask.

In the method of manufacturing a high-resolution mask according to claim 7, a step of forming an initial mask pattern based on predetermined pattern data, and a step of transmitting the initial mask pattern through a transparent substrate in a phase shift mask. Dividing a portion into a plurality of types of mask patterns on the basis of the pattern shape and the pattern density based on data on a loading effect when forming a dug portion by etching a portion, and a plurality of final patterns for each of the plurality of types of mask patterns. A mask having substantially the same pattern shape and pattern density that does not cause a loading effect by having a step of forming a mask pattern and a step of forming a plurality of phase shift masks for each of the plurality of final mask patterns. Is the pattern initially a mask pattern Extracted and divided disposed in each of the plurality of final mask pattern, corresponding to the plurality of final mask pattern, a plurality of phase shift mask for forming a resist pattern of one layer is manufactured. Therefore, when manufacturing each of the plurality of phase shift masks, when a transparent portion of the transparent substrate is etched to form a digging, a loading effect due to a difference in pattern shape and pattern density occurs. As a result, the digging of the desired depth is accurately formed. Therefore, a plurality of phase shift masks, each of which can control the phase difference with high precision, is realized.

According to a eighth aspect of the present invention, in the method of manufacturing a high resolution mask according to the seventh aspect, a plurality of phase shift masks are manufactured for each of a plurality of final mask patterns. In addition, a mask pattern other than a fine pattern is arranged on a plurality of phase shift masks without imparting a phase difference.

As a resist used for forming a fine pattern, a positive resist is generally used because it has a high dry etching resistance and has excellent process stability with no residue left during development. Has been adopted. However, when a positive resist is used when forming a fine pattern using a phase shift mask, an unnecessary pattern is formed in addition to the fine pattern using the phase shift mask. In addition, normal exposure for eliminating the unnecessary pattern is required. For this reason, besides the phase shift mask,
A mask used for normal exposure that eliminates unnecessary patterns is required. On the other hand, in the method of manufacturing a high-resolution mask according to claim 8, a plurality of final mask patterns are formed by utilizing the fact that a plurality of phase shift masks for forming a one-layer resist pattern are manufactured. A mask that eliminates unnecessary patterns other than fine patterns by arranging mask patterns other than fine patterns on a plurality of phase shift masks without imparting a phase difference when manufacturing a plurality of phase shift masks for each The pattern is formed by being incorporated into the phase shift mask. For this reason, a mask used for normal exposure that eliminates unnecessary patterns becomes unnecessary, and the number of masks can be reduced accordingly, and the number of exposures can be reduced accordingly.

For example, based on the data on the loading effect, the pattern shape and pattern density
When two final mask patterns are formed by dividing into two types of mask patterns, two phase shift masks are manufactured to form a one-layer resist pattern. In comparison with the case where one phase shift mask and a normal mask for eliminating unnecessary patterns are required to form the resist pattern of FIG. Does not increase. When arranging a mask pattern other than a fine pattern on a plurality of phase shift masks without imparting a phase difference, the fine pattern having a phase difference formed on the phase shift mask is not affected in the first place. It is necessary to keep in mind.

According to a ninth aspect of the present invention, there is provided a method for manufacturing a high resolution mask, comprising the steps of: forming an initial mask pattern based on predetermined pattern data; A step of dividing into a plurality of types of mask patterns based on the pattern shape and the pattern density based on the degree data, a step of creating a plurality of final mask patterns for each of the plurality of types of mask patterns, And a step of producing a plurality of high-resolution masks.

Thus, in the method of manufacturing a high resolution mask according to the ninth aspect, a step of forming an initial mask pattern based on predetermined pattern data, and a step of forming a depth of focus and an exposure for the initial mask pattern at the time of exposure. A step of dividing into a plurality of types of mask patterns on the basis of the pattern shape and the pattern density based on the data regarding the allowance of the amount; a step of creating a plurality of final mask patterns for each of the plurality of types of mask patterns; For each final mask pattern, having a step of producing a plurality of high-resolution masks, so that substantially the same pattern shape and pattern as to ensure a sufficient depth of focus and a sufficient amount of exposure during exposure. The density mask pattern is extracted from the initial mask pattern to S the divided arrangement, in correspondence to the plurality of final mask pattern, it is possible to produce a plurality higher resolution mask for forming a resist pattern of the one layer. For this reason, when performing multiple exposure processing using these plural high-resolution masks to form a resist pattern of one layer, a sufficient depth of focus and a sufficient amount of exposure are required for the multiple exposure processing. Secured. Therefore, a high-resolution mask capable of easily securing the optimum exposure condition and increasing the lithography process latitude is manufactured.

In the method for manufacturing a high-resolution mask according to the ninth aspect, the plurality of high-resolution masks manufactured for each of the plurality of final mask patterns may include light transmitted through both sides of the fine pattern in the fine line width direction. It is preferable to use a phase shift mask that improves the resolving power by using the interference effect due to the phase difference (claim 10).

That is, the method of manufacturing a high-resolution mask according to the ninth aspect is not limited to the method of manufacturing a phase shift mask, but can be applied when manufacturing a phase shift mask. In such a case, when performing multiple exposure processing using a plurality of phase shift masks manufactured using the method for manufacturing a high resolution mask, sufficient depth of focus and a sufficient amount of exposure are ensured respectively. At the same time, it becomes possible to set optimal optical conditions for each exposure. Therefore, a phase shift mask capable of easily securing the optimum exposure condition and increasing the lithography process latitude is manufactured.

According to another aspect of the present invention, there is provided a resist pattern forming method using a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction. When forming an initial mask pattern based on predetermined pattern data, and forming a digging having a different depth by etching an adjacent transmission portion of a transparent substrate in a phase shift mask with respect to the initial mask pattern. Based on the data related to the loading effect, the pattern is divided into a plurality of types of mask patterns based on the pattern shape and the pattern density, a plurality of final mask patterns are created for each of the plurality of types of mask patterns, and for each of the plurality of final mask patterns, Producing a plurality of phase shift masks;
Performing a multiple exposure process using a plurality of phase shift masks to form a one-layer resist pattern to which a plurality of final mask patterns have been transferred.

As described above, in the method for forming a resist pattern according to the eleventh aspect, the step of manufacturing a plurality of phase shift masks using the method for manufacturing a high resolution mask according to the seventh aspect includes the steps of: Performing a multiple exposure process using a phase shift mask to form a one-layer resist pattern to which a plurality of final mask patterns have been transferred. Since a one-layer resist pattern is formed by multiple exposure processing using a shift mask, the pattern shape controllability and transfer position accuracy of the resist pattern are improved.

According to a twelfth aspect of the present invention, in the method of forming a resist pattern according to the eleventh aspect, a fine pattern is formed when a plurality of phase shift masks are manufactured for each of a plurality of final mask patterns. The mask pattern other than the fine pattern is arranged on a plurality of phase shift masks without imparting a phase difference, and the multi-exposure is performed using the plurality of phase shift masks where the mask patterns other than the fine pattern are arranged without imparting a phase difference. The process is performed to form a one-layer resist pattern in which a plurality of final mask patterns are transferred.

As described above, in the resist pattern forming method according to the twelfth aspect, a multiple exposure process is performed using a plurality of phase shift masks manufactured by applying the high resolution mask manufacturing method according to the eighth aspect. Forming a one-layer resist pattern to which a plurality of final mask patterns have been transferred, so that a mask pattern for eliminating unnecessary patterns other than the fine pattern is incorporated in the phase shift mask. Since a one-layer resist pattern is formed using a shift mask, a mask used for normal exposure for eliminating unnecessary patterns becomes unnecessary, and the number of masks can be reduced accordingly. The number of exposures can be reduced. When arranging a mask pattern other than a fine pattern on a plurality of phase shift masks without imparting a phase difference, the fine pattern having a phase difference formed on the phase shift mask is not affected in the first place. It is necessary to keep in mind.

A resist pattern forming method according to a thirteenth aspect is a resist pattern forming method using a high-resolution mask, wherein the resist pattern is formed based on predetermined pattern data.
Initially, a mask pattern is created, and the initial mask pattern is divided into a plurality of types of mask patterns based on the pattern shape and the pattern density based on data on the depth of focus and the latitude of the exposure amount at the time of exposure. For each mask pattern, create a plurality of final mask patterns, for each of the plurality of final mask patterns, create a plurality of high-resolution masks, and perform multiple exposure processing using the plurality of high-resolution masks. Forming a one-layer resist pattern to which a plurality of final mask patterns have been transferred.

As described above, in the method for forming a resist pattern according to the thirteenth aspect, using the method for manufacturing a high-resolution mask according to the ninth aspect, a step of manufacturing a plurality of high-resolution masks, Performing a multiple exposure process using a high-resolution mask to form a one-layer resist pattern to which a plurality of final mask patterns have been transferred, thereby ensuring a sufficient depth of focus and a sufficient amount of exposure for each. A single-layer resist pattern is formed by multiple exposure processing using a plurality of high-resolution masks, so that each exposure processing using each high-resolution mask requires a sufficient depth of focus and exposure amount. And the optimal optical conditions can be set for each high-resolution mask. Therefore, optimal exposure conditions are easily secured, and the lithography process latitude is increased.

In the method for forming a resist pattern according to the thirteenth aspect, the plurality of high-resolution masks produced for each of the plurality of final mask patterns are arranged so that the positions of light transmitted through both sides of the fine pattern in the fine line width direction are respectively determined. It is preferable to use a phase shift mask that improves the resolving power by using the interference effect due to the phase difference.

That is, the method for forming a resist pattern according to claim 13 is not limited to the method for forming a resist pattern using a phase shift mask, but can be applied to the case where a phase shift mask is used. . In such a case, when performing multiple exposure processing using a plurality of phase shift masks to form a resist pattern of one layer, a sufficient depth of focus and a sufficient amount of exposure are ensured for each. In addition, it becomes possible to set optimal optical conditions for each high resolution mask. Therefore, optimal exposure conditions are easily secured, and the lithography process latitude is increased.

[0042]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described. (First Embodiment) FIG. 1 is a schematic block diagram showing a Levenson phase shift mask pattern forming apparatus according to a first embodiment of the present invention, and FIG. 2 incorporates the Levenson phase shift mask pattern forming apparatus of FIG. FIG. 2 is a schematic block diagram illustrating an apparatus for manufacturing a Levenson phase shift mask.

As shown in FIG. 1, the Levenson phase shift mask pattern forming apparatus according to the present embodiment has a pattern data input section 11 for inputting predetermined pattern data.
And a loading data input section 12 for inputting data relating to a loading effect when a digging is formed by etching a transparent portion of a transparent substrate in a phase shift mask.
And a Levenson phase shift mask pattern creating unit 20 that performs a predetermined process based on the predetermined pattern data and the data related to the loading effect input to the pattern data input unit 11 and the loading data input unit 12 to create a final mask pattern. It is roughly divided.

In the Levenson phase shift mask pattern creating section 20, the pattern data input section 11
A first mask pattern creation unit 21 for initially creating a mask pattern based on predetermined pattern data input to
The initial mask pattern created by the first mask pattern creation unit 21 is converted into a plurality of types of mask patterns based on the pattern shape and pattern density of the fine pattern based on the loading effect data input to the loading data input unit 12. Pattern dividing section 22 for dividing and first mask pattern creating section 21
And a plurality of final mask patterns for each of a plurality of types of mask patterns divided by the pattern dividing unit 22. And a second mask pattern creating unit 24 that arranges a binary mask pattern other than the fine pattern created by the binary mask pattern creating unit 23 on the plurality of final mask patterns. Here, a similar effect is exerted by providing a halftone phase shift mask pattern creating section for creating a mask pattern of a halftone phase shift mask instead of the binary mask pattern creating section 23.

As shown in FIG. 2, the Levenson phase shift mask producing apparatus incorporating the mask pattern producing apparatus of FIG.
In addition to the loading data input unit 12 and the Levenson phase shift mask pattern creation unit 20, a plurality of Levenson phase shift masks are specifically created for each of the plurality of final mask patterns created by the Levenson phase shift mask pattern creation unit 20. Is provided. The Levenson phase shift mask manufacturing unit 30 has the same configuration as a normal Levenson phase shift mask manufacturing unit. Specifically, based on the final mask pattern created by the Levenson phase shift mask pattern creating section 20, a pattern drawing for forming an original pattern on a mask blank on which a light shielding film is formed on a quartz substrate and a resist film is applied. A light-shielding film etching unit 32 for selectively etching the light-shielding film using the resist film of the original pattern drawn in the pattern drawing unit 31 as a mask
And a quartz substrate etching section 33 for selectively etching the quartz substrate in the transmission section not covered with the light-shielding film to form a dig with a different depth for each adjacent transmission section.
And a cleaning unit 34 for cleaning the mask blank after removing the resist film of the original pattern, a line width of a light shielding film formed on a quartz substrate, a space width of a transmission part sandwiched between the light shielding films, and a predetermined position. The line width / phase difference measuring unit 35 for measuring the depth of digging for generating a phase difference and the like and the mask pattern formed of a light shielding film formed on a quartz substrate are inspected for defects, and the defects are corrected. And a defect correction unit 36 to be provided.

Next, a method for manufacturing a Levenson phase shift mask using the apparatus for manufacturing a Levenson phase shift mask shown in FIG. 2 will be described with reference to FIGS. Here, FIGS. 3A and 3B respectively show data on the loading effect in the pattern dividing section 22 for the initial mask pattern created in the first mask pattern creating section 21 of the Levenson phase shift mask manufacturing apparatus in FIG. 4A and 4B are plan views showing a plurality of types of mask patterns divided on the basis of the pattern shape and pattern density of the fine pattern based on FIG. FIG. 5 is a plan view schematically showing a plurality of final mask patterns created by a second mask pattern creation unit 24;
2A and 2B respectively show a plurality of final mask patterns produced by the Levenson phase shift mask producing section 30 for each of the plurality of final mask patterns produced by the Levenson phase shift mask pattern producing section 20 of the apparatus for producing a Levenson phase shift mask shown in FIG. FIG. 4 is a schematic cross-sectional view showing one Levenson phase shift mask.

First, predetermined pattern data is input to the pattern data input section 11. Further, data relating to a loading effect when the transparent portion of the transparent substrate in the phase shift mask is etched to form the digging is input to the loading data input unit 12. Then, based on the predetermined pattern data input to the pattern data input unit 11, the Levenson phase shift mask pattern generation unit 2
First, a first mask pattern creation unit 21 creates a mask pattern. Here, as the initial mask pattern created by the first mask pattern creation unit 21, a D of the design rule 0.10 μm generation is used.
Assume a pattern of a RAM and a logic circuit.

Next, in the pattern division section 22, the first
For the initial mask pattern created by the mask pattern creation unit 21 of FIG.
Based on the loading effect data you entered in,
The pattern is divided into a plurality of types of mask patterns based on the pattern shape and pattern density of the fine pattern. Specifically, as shown in FIGS. 3A and 3B, respectively.
The mask pattern was divided into two types of gate patterns. That is, an isolated pattern having a line width L = 0.10 μm and a shifter width S = 0.24 μm of the phase shift mask in the logic portion as shown in FIG. And a mask pattern as shown in FIG.
There are two types of L & S (line-and-space) patterns having a line width L = 0.10 μm and a space width S = 0.24 μm in the RAM section, and a mask pattern having a pattern shape and a pattern density substantially similar to the L & S pattern. .

Although not shown, the binary mask pattern creating section 23 extracts a binary mask pattern other than a fine pattern such as a gate pattern from the initial mask pattern created by the first mask pattern creating section 21. To create. Subsequently, in the second mask pattern creation unit 24, the pattern division unit 2
4A and 4B for each of the two types of mask patterns shown in FIGS. 3A and 3B divided in FIG.
The two final mask patterns as shown in FIG.
And second final mask patterns 41 and 42, respectively. Further, a binary mask pattern other than the fine pattern created by the binary mask pattern creating section 23 is arranged on the first and second final mask patterns 41 and 42 shown in FIGS. 4A and 4B, respectively.

Thus, in the first final mask pattern 41 shown in FIG. 4A, a gate pattern of an isolated pattern as shown in FIG. 3A is formed in the logic gate portion 43a. The second shown in (b)
3B, the gate pattern of the L & S pattern as shown in FIG.
It is formed in the RAM cell section 44a. Further, in the first final mask pattern 41, the binary mask pattern created by the binary mask pattern creating section 23 is added to the DRAM peripheral circuit section 44b corresponding to the peripheral section of the DRAM cell section 44a of the second final mask pattern 42. A pattern (a mask pattern other than a fine gate pattern) is formed, and in the second final mask pattern 42, a binary mask pattern forming section The binary mask pattern (mask pattern other than the fine gate pattern) created in 23 is formed.

That is, in the first final mask pattern 41, the logic gate portion 43a, which is hatched in the drawing,
Denotes a region serving as a phase shifter providing portion, and a region where the DRAM peripheral circuit portion 44b with dots is provided serves as a binary mask portion. In the second final mask pattern 42, the hatched DRAM cell portion 44a in the drawing is a region to be a phase shifter providing portion, and the region 43b overlapping the dot-added logic gate portion 43a is a binary region. This is a region to be a mask portion.

Next, in the Levenson phase shift mask producing section 30, the first and second final mask patterns 41, 42 produced in the second mask pattern producing section 24 of the Levenson phase shift mask pattern producing section 20.
Are produced, that is, first and second Levenson phase shift masks 51 and 52 as shown in FIGS. 5A and 5B, respectively. Here, FIG. 5A shows a portion corresponding to the logic gate portion 43a of the first final mask pattern 41, and FIG. 5B shows the second final mask pattern 42.
3 shows a portion corresponding to the DRAM cell section 44a.

That is, as shown in FIG.
In the logic gate portion of the Levenson phase shift mask 51, light shielding films 54a, 54b,
54c, and these light shielding films 54a, 54b, 54
When the digging is formed by selectively etching the quartz substrate 53 in the transmitting portion sandwiched between the gate portions c, for example, the gate pattern has a low pattern density as represented by the isolated pattern in FIG. Even in the case of a mask pattern, since the pattern shape and pattern density in this fine pattern are substantially the same throughout the entire first Levenson phase shift mask 51, the occurrence of a loading effect due to the difference in pattern shape and pattern density is prevented. You. As a result, the width of the light shielding films 54a, 54b, 54c is 100 ×
4 nm, and these light shielding films 54a, 54b, 54c
In the adjacent transmissive portion sandwiched between the two, a dug 55 having a width of 240 × 4 nm and a depth of 380 nm and a dug 56 having a width of 240 × 4 nm and a depth of 380 nm + 230 nm = 610 nm 56 are formed.
Are formed, and a desired phase difference of 171 ° is generated.

Further, as shown in FIG.
In the DRAM cell portion of the Levenson phase shift mask 52, the light shielding films 54d, 54e,
4f, and these light-shielding films 54d, 54e, 54f
When the digging is formed by selectively etching the quartz substrate 53 of the transmission part sandwiched between the masks, for example, a mask having a high pattern density such as the gate pattern represented by the L & S pattern in FIG. Even in the case of a pattern, the pattern shape and pattern density of this fine pattern are substantially the same over the entire second Levenson phase shift mask 52, so that the occurrence of a loading effect due to the difference in pattern shape and pattern density is prevented. . As a result, the width of the light shielding films 54d, 54e, 54f is 100 ×
4 nm, and these light-shielding films 54d, 54e, 54f
In the adjacent transmissive portion sandwiched between them, a dug 57 having a width of 240 × 4 nm and a depth of 380 nm and a dug 58 having a width of 240 × 4 nm and a depth of 380 nm + 230 nm = 610 nm 58 are formed.
Are formed, and a desired phase difference of 171 ° is generated.

As described above, the logic gate unit and the DR
Even if there is a great difference in the pattern shape and pattern density of the fine pattern from the AM cell part, it is separated into first and second Levenson phase shift masks 51 and 52, and the fine pattern in the respective Levenson phase shift masks Since the pattern shape and the pattern density are substantially the same, the occurrence of the loading effect due to the difference between the pattern shape and the pattern density is prevented, and the first and second patterns are not formed.
In the respective Levenson phase shift masks 51 and 52, dug portions 55 and 56; 57 and 58 having a desired depth are formed, respectively, and two Levenson phase shift masks which together generate a desired phase difference of 171 ° are manufactured. You.
Although not shown, in each of the first and second Levenson phase shift masks 51 and 52, in addition to a fine gate pattern provided with a phase shifter of a logic gate portion and a DRAM cell portion, a DRAM peripheral circuit is provided. A binary pattern to which a phase shifter is not provided is formed in a portion or the like.

Next, although not shown, a pattern is formed using the first and second Levenson phase shift masks 51 and 52 manufactured in the Levenson phase shift mask manufacturing section 30. That is, a desired phase difference 17 is applied to a semiconductor substrate having a predetermined resist film applied on its surface.
Using the first and second Levenson phase shift masks 51 and 52 that generate 1 °, two multiple exposure processes are performed,
Further, through a process such as development and cleaning, a resist pattern of one layer is formed by overlappingly transferring the mask patterns of the first and second Levenson phase shift masks 51 and 52.

As described above, according to the present embodiment, the initial mask pattern created based on the predetermined pattern data is divided on the basis of the pattern shape and pattern density of the fine pattern based on the data relating to the loading effect. And second final mask patterns 41 and 42, and first and second Levenson phase shift masks 51 and 52 corresponding to the first and second final mask patterns 41 and 42, respectively. The first and second Levenson phase shift masks 5 can be used even if fine patterns having a large difference in pattern shape and pattern density are mixed in the initial mask pattern.
Since the pattern shape and the pattern density of the fine pattern in each of 1 and 52 are substantially the same, when the digging is formed by etching the transmission part of the phase shifter applying part, it is caused by the difference in the pattern shape and the pattern density. The occurrence of the loading effect is prevented, the digging of a desired depth can be formed with high accuracy, and a desired phase difference can be generated. Accordingly, highly accurate phase difference control of the Levenson phase shift mask can be easily performed, and the production yield is also improved. Therefore, a high-performance Levenson phase shift mask can be manufactured at low cost.

In addition, the first and second Levenson phase shift masks 51 and 5 which both generate a desired phase difference are provided.
2 to form a resist pattern of one layer by performing multiple exposure processes twice, thereby improving pattern shape controllability and transfer position accuracy when forming a fine resist pattern.

When a positive resist is used in forming a pattern using a phase shift mask, a mask used for normal exposure for eliminating unnecessary patterns other than fine patterns is required. Since the second Levenson phase shift masks 51 and 52 are formed with not only a fine gate pattern provided with a phase shifter but also a binary pattern not provided with a phase shifter.
A mask used for normal exposure for eliminating unnecessary patterns becomes unnecessary, and only two masks, ie, the first and second Levenson phase shift masks 51 and 52, are used. It is possible to avoid an increase in the number of masks as compared with the conventional case that requires the above mask. Therefore, the throughput does not lower than in the conventional case.

Further, when performing multiple exposure processing using the first and second Levenson phase shift masks 51 and 52, it becomes possible to set optimal optical conditions for each of them, so that the tolerance of the lithography process is reduced. It is possible to make it larger. Therefore, manufacturing yield and reliability can be improved, and throughput can be increased.

(Second Embodiment) FIG. 6 is a schematic block diagram showing a high-resolution mask pattern forming apparatus according to a second embodiment of the present invention, and FIG. 7 shows the high-resolution mask pattern forming apparatus of FIG. FIG. 2 is a schematic block diagram showing a high-resolution mask manufacturing apparatus incorporated therein.

The high-resolution mask pattern producing apparatus and the high-resolution mask producing apparatus according to the present embodiment include the Levenson phase shift mask pattern producing apparatus and the Levenson phase shift mask producing apparatus. The present invention is not limited to the Levenson phase shift mask pattern forming apparatus and the Levenson phase shift mask forming apparatus as in the case of the embodiment.

As shown in FIG. 6, the high-resolution mask pattern forming apparatus according to the present embodiment includes a pattern data input unit 61 for inputting predetermined pattern data, a depth of focus and a tolerance of an exposure amount at the time of exposure. Depth of focus and exposure amount data input unit 62 for inputting data related to the predetermined pattern data, focal depth and exposure amount input to the pattern data input unit 61 and the depth of focus and exposure amount tolerance data input unit 62 And a high-resolution mask pattern creation unit 70 that performs a predetermined process based on the data regarding the margin and creates a final mask pattern.

Then, the high-resolution mask pattern creating section 7
0, a first mask pattern creating unit 71 that creates an initial mask pattern based on predetermined pattern data input to the pattern data input unit 61, and an initial mask pattern created by the first mask pattern creating unit 71. A pattern to be divided into a plurality of types of mask patterns on the basis of the pattern shape and pattern density of the fine pattern based on the data on the depth of focus and the latitude of the exposure amount input to the depth of focus and the latitude of the exposure amount data input unit 62. The dividing unit 72 and the pattern dividing unit 72
And a second mask pattern creating section 73 for creating a plurality of final mask patterns for each of the plurality of types of mask patterns divided in.

As shown in FIG. 7, the high-resolution mask producing apparatus incorporating the mask pattern producing apparatus shown in FIG. 6 includes the above-described pattern data input section 61, depth of focus and exposure tolerance data input section 62. , And a high-resolution mask forming unit that specifically manufactures a plurality of high-resolution masks for each of the plurality of final mask patterns generated by the high-resolution mask pattern forming unit 70 80 are provided. And
The high-resolution mask manufacturing unit 80 has the same configuration as a normal high-resolution mask manufacturing unit. Specifically, based on the final mask pattern created by the high-resolution mask pattern creation unit 70, a pattern drawing unit that draws an original image pattern on a mask blank on which a light shielding film is formed on a quartz substrate and a resist film is applied. 81, a light-shielding film etching portion 82 for selectively etching the light-shielding film using the resist film of the original pattern drawn in the pattern drawing portion 81 as a mask, and a quartz substrate in the transmission portion not covered with the light-shielding film. A quartz substrate etching portion 83 for forming a digging having a different depth for each adjacent transmission portion by etching, a cleaning portion 84 for cleaning a mask blank after removing a resist film of an original pattern, and a quartz substrate Engraving to generate the line width of the formed light shielding film, the space width of the transmissive portion sandwiched between the light shielding films, and a predetermined phase difference The line width and phase difference measuring section 85 for measuring the depth or the like and inspected for defects in the mask pattern made of light shielding film formed on a quartz substrate, the defect correcting section 86 to correct the defect
Are provided.

Next, a method for manufacturing a high-resolution mask using the high-resolution mask manufacturing apparatus shown in FIG. 7 will be described with reference to FIG. Here, FIGS. 8A and 8B show the depth of focus and the exposure amount of the initial mask pattern created by the first mask pattern creating unit 71 of the high-resolution mask manufacturing apparatus of FIG. 7 is a graph showing ED windows for a plurality of types of mask patterns divided on the basis of the pattern shape and the pattern density of the fine pattern based on the data regarding the margins. Note that, regarding the initial mask pattern created in the first mask pattern creating unit 71 of the high resolution mask manufacturing apparatus in FIG. 7, the pattern dividing unit 72 uses the pattern of the fine pattern based on the data on the depth of focus and the latitude of the exposure amount. A plan view showing a plurality of types of mask patterns divided based on the shape and the pattern density is the same as that shown in FIGS. 3A and 3B of the first embodiment, and the high resolution shown in FIG. For each of the plurality of final mask patterns created in the high-resolution mask pattern creating section 70 of the mask manufacturing apparatus, a schematic cross-sectional view showing a part of the plurality of high-resolution masks created in the high-resolution mask creating section 80 is shown in FIG. FIG. 5A of the first embodiment,
3 and 5 are also used in the description of the present embodiment because they are the same as those shown in FIG.

First, predetermined pattern data is input to the pattern data input section 61. In addition, data relating to the depth of focus and the amount of exposure during exposure is input to the depth of focus and the amount of exposure data input unit 62. Then, based on the predetermined pattern data input to the pattern data input unit 61, the first mask pattern creation unit 71 of the high resolution mask pattern creation unit 70 creates an initial mask pattern. Here, as the initial mask pattern created by the first mask pattern creation unit 71, a pattern of a 0.10 μm design rule DRAM and a logic circuit is assumed.

Next, in the pattern division section 72, the first
For the initial mask pattern created by the mask pattern creation unit 71, the pattern shape of the fine pattern and the pattern shape of the fine pattern are determined based on the data on the depth of focus and the latitude of the exposure input to the depth of focus and the latitude of the exposure input to the tolerance data input unit 62. It is divided into a plurality of types of mask patterns based on the pattern density. Specifically, FIG. 3 of the first embodiment described above
The mask pattern was divided into two types of mask patterns similar to those shown in FIGS. That is, the line width L = 0.10 μm in the logic section as shown in FIG.
m, an isolated pattern having a phase shift mask shifter width S = 0.24 μm, a mask pattern having a pattern shape and a pattern density substantially similar to the isolated pattern, and FIG.
The line width L in the DRAM section as shown in FIG.
L & S with = 0.10 μm and space width S = 0.24 μm
(Line and space) pattern and this L &
There are two types of mask patterns having the same pattern shape and pattern density as the S pattern.

Subsequently, a second mask pattern creating section 73
In FIG.
Two final mask patterns are created for each of the two types of mask patterns shown in (a) and (b). Thus, in one final mask pattern of the two final mask patterns, a gate pattern of an isolated pattern as shown in FIG. 3A is formed in the logic gate portion, and in the other final mask pattern, An L & S pattern gate pattern as shown in FIG. 3B is formed in the DRAM cell portion.

Next, in the high-resolution mask producing section 80, two high-resolution masks corresponding to the two final mask patterns produced in the second mask pattern producing section 73 of the high-resolution mask pattern producing section 70 are stored. Make it. However, here, as these two high-resolution masks, the same first and second Levenson phase shift masks 51 as those shown in FIGS. 5A and 5B of the first embodiment, 52 shall be manufactured.

That is, as shown in FIG.
In the logic gate portion of the Levenson phase shift mask 51, light-shielding films 54a, 54b, and 54c having a width of 100 × 4 nm are formed on a quartz substrate 53, and adjacent light-transmitting films sandwiched between these light-shielding films 54a, 54b, and 54c. In the part, a dug 55 with a width of 240 × 4 nm and a depth of 380 nm
And a dug 56 with a width of 240 × 4 nm and a depth of 610 nm
Are formed, and a desired phase difference of 171 ° is generated. Further, as shown in FIG. 5B, the DRAM of the second Levenson phase shift mask 52 is used.
In the cell part, a width of 100 × 4 nm is formed on the quartz substrate 53.
Light-shielding films 54d, 54e, and 54f are formed, and in the adjacent transmission portion sandwiched between these light-shielding films 54d, 54e, and 54f, a dug 57 having a width of 240 × 4 nm and a depth of 380 nm and a width of 240 × 4 nm, Engraved portions 58 having a depth of 610 nm are formed to generate a desired phase difference of 171 °.

Next, although not shown, a pattern is formed using the first and second Levenson phase shift masks 51 and 52 manufactured in the Levenson phase shift mask manufacturing section 30. That is, a desired phase difference 17 is applied to a semiconductor substrate having a predetermined resist film applied on its surface.
Using the first and second Levenson phase shift masks 51 and 52 that generate 1 °, two multiple exposure processes are performed,
Further, through a process such as development and cleaning, a resist pattern of one layer is formed by overlappingly transferring the mask patterns of the first and second Levenson phase shift masks 51 and 52.

Then, a light intensity simulation is performed for the multiple exposure processing using the first and second Levenson phase shift masks 51 and 52, and an ED window at that time is obtained, as shown in FIGS. 8 (a) and 8 (b). Respectively as shown in the graph. In this light intensity simulation, as shown in FIGS. 3A and 3B, the gate length of the logic portion and the DRAM portion was 0.10 μm.
Assuming that the specification of the resist transfer line width for the gate pattern of m is 0.10 ± 0.01 μm, the optical conditions shown in the following table were used.

[0074]

[Table 1]

First, in the case of performing exposure using the first Levenson phase shift mask 51, the line width specification boundary line in the logic gate portion is shown by a solid line in FIG. When the ED window including the latitude of the exposure amount and the latitude of the depth of focus is obtained, the latitude of the exposure amount is 13.2% and the latitude of the depth of focus is 0.6 μm.
m. When the exposure is performed by using the second Levenson phase shift mask 52, the line width specification boundary line in the DRAM cell portion is shown by a solid line in FIG. When the ED window including the latitude of the depth of focus and the latitude of the depth of focus is obtained, the latitude of the exposure amount is 11.6% and the latitude of the depth of focus is 0.4 μm.
It became. Therefore, when multiple exposure is performed using the first and second Levenson phase shift masks 51 and 52, the gate pattern of the DRAM cell portion is transferred even when the gate pattern of the logic gate portion is transferred. In any case, the tolerance of the exposure amount and the tolerance of the depth of focus are 5.3% and the tolerance of the conventional depth of focus shown in the graph of FIG. .4μ
It becomes larger than the case of m.

As described above, according to the present embodiment, the initial mask pattern created based on the predetermined pattern data is divided based on the pattern shape and pattern density of the fine pattern based on the data on the depth of focus and the latitude of the exposure amount. And create two final mask patterns,
Furthermore, by manufacturing the first and second Levenson phase shift masks 51 and 52 corresponding to these two final mask patterns, respectively, fine patterns having a large difference in pattern shape and pattern density are mixed in the initial mask pattern. However, since the pattern shape and pattern density of the fine pattern in each of the first and second Levenson phase shift masks 51 and 52 are substantially the same,
These first and second Levenson phase shift masks 5
It is possible to increase the latitude of the exposure amount and the latitude of the depth of focus when performing exposure using the light sources 1 and 52. Therefore, the first and second Levenson phase shift masks 5 having large latitudes of the exposure amount and the depth of focus respectively.
By performing a multiple exposure process twice using 1 and 52 to form a resist pattern of one layer, it is possible to easily secure an optimum exposure condition when forming a fine resist pattern and to increase a lithography process margin. Can be bigger.

Further, when performing multiple exposure processing using the first and second Levenson phase shift masks 51 and 52, it is possible to set optimal optical conditions for each of the multiple exposure processing. It is possible to increase the degree. Therefore, manufacturing yield and reliability can be improved, and throughput can be increased.

[0078]

As described above in detail, according to the mask pattern forming apparatus, the high resolution mask forming apparatus and the manufacturing method, and the resist pattern forming method using the high resolution mask according to the present invention, the following is provided. Such effects can be obtained. That is, according to the mask pattern creating apparatus of the first aspect, based on the predetermined pattern data,
A first mask pattern forming section for forming an initial mask pattern, and a pattern shape of the initial mask pattern based on data on a loading effect when a transparent portion of a transparent substrate in a phase shift mask is etched to form a digging. And a pattern division unit for dividing into a plurality of types of mask patterns based on the pattern density,
By providing a second mask pattern creating section for creating a plurality of final mask patterns for each of a plurality of types of mask patterns divided by the pattern dividing section, substantially the same pattern shape that does not cause a loading effect Since a plurality of final mask patterns are created by extracting a mask pattern having a pattern density from the initial mask pattern and separately arranging the mask patterns, a one-layer resist pattern is formed in correspondence with the plurality of final mask patterns. When manufacturing each of the plurality of phase shift masks, when forming a digging by etching the transparent portion of the transparent substrate, to prevent the occurrence of a loading effect due to the difference in pattern shape and pattern density In addition, it is possible to accurately form a digging of a desired depth.
Therefore, it is possible to realize a plurality of phase shift masks, each of which can control the phase difference with high accuracy.

Further, according to the mask pattern creating apparatus of the present invention, a first mask pattern creating section for creating an initial mask pattern based on predetermined pattern data, A pattern division unit that divides the pattern into a plurality of types of mask patterns based on the pattern shape and the pattern density based on the data on the depth of focus and the latitude of the exposure amount, and a plurality of types of mask patterns divided by the pattern division unit. And a second mask pattern creating section for creating a plurality of final mask patterns, so that a substantially similar pattern shape and pattern are obtained to the extent that a sufficient depth of focus and a sufficient amount of exposure can be secured during exposure. A plurality of final mask patterns in which the density mask pattern is extracted from the initial mask pattern and divided and arranged for each In order to form a one-layer resist pattern by performing multiple exposure processing using a plurality of high-resolution masks manufactured in correspondence with the plurality of final mask patterns, when the multiple exposure processing is performed, It is possible to ensure a sufficient depth of focus and a sufficient amount of exposure for each. Therefore, it is possible to realize a high-resolution mask capable of easily securing the optimum exposure conditions and increasing the lithography process latitude.

According to a fourth aspect of the present invention, there is provided an apparatus for producing a mask pattern according to the first aspect, wherein a plurality of phase shift masks are provided for each of a plurality of final mask patterns produced therein. And a mask pattern having a substantially similar pattern shape and pattern density that does not cause a loading effect by extracting a mask pattern from the initial mask pattern and arranging the mask pattern in each of a plurality of final mask patterns. However, since a plurality of phase shift masks for forming a one-layer resist pattern are produced corresponding to the plurality of final mask patterns, when producing each of the plurality of phase shift masks, When etching the transparent part of the transparent substrate to form a dug, the pattern shape and pattern density Different from and prevent loading effects due to, it is possible to accurately form the digging of a desired depth. Accordingly, highly accurate phase difference control of the Levenson phase shift mask can be easily performed, and the production yield is also improved. Therefore, a high-performance Levenson phase shift mask can be manufactured at low cost.

According to the apparatus for producing a high-resolution mask according to the fifth aspect, the apparatus for producing a mask pattern according to the second aspect and a plurality of high-resolution masks for each of a plurality of final mask patterns produced there. By having a high-resolution mask manufacturing section to be manufactured, a mask pattern having a substantially similar pattern shape and pattern density to the extent that it is possible to secure a sufficient depth of focus and a sufficient amount of exposure at the time of exposure is initially provided. A plurality of high-resolution masks for forming a one-layer resist pattern corresponding to the plurality of final mask patterns are extracted from the mask pattern and divided and arranged in each of the plurality of final mask patterns. This makes it possible to form a one-layer resist pattern by performing multiple exposure processing using these multiple high-resolution masks. , During its multiple exposure process, you are possible to secure a sufficient depth of focus and exposure dose latitude, respectively. Accordingly, a high-resolution mask capable of easily securing the optimum exposure conditions and increasing the lithography process latitude can be manufactured.

Further, according to the method of manufacturing a high resolution mask according to claim 7, a step of forming an initial mask pattern based on predetermined pattern data, and transmitting the initial mask pattern through a transparent substrate in a phase shift mask. Dividing a plurality of types of mask patterns on the basis of the pattern shape and the pattern density based on data on a loading effect when forming a dug portion by etching a portion, and forming a plurality of final patterns for each of the plurality of types of mask patterns. A mask having substantially the same pattern shape and pattern density as does not cause a loading effect by having a step of forming a mask pattern and a step of forming a plurality of phase shift masks for each of the plurality of final mask patterns. Extract patterns from initial mask pattern And a plurality of phase shift masks for forming a one-layer resist pattern corresponding to the plurality of final mask patterns are produced. When fabricating each of the phase shift masks, when a transparent portion of the transparent substrate is etched to form a digging, the occurrence of a loading effect due to a difference in pattern shape and pattern density is prevented, and a desired depth is obtained. It is possible to accurately form the digging. Therefore, high-precision phase difference control of the Levenson phase shift mask can be easily performed, and the production yield is also improved.
A high-performance Levenson phase shift mask can be manufactured at low cost.

According to a method of manufacturing a high resolution mask according to claim 8, in the method of manufacturing a high resolution mask according to claim 7, a plurality of phase shift masks for forming a one-layer resist pattern are provided. By making use of the fact that a plurality of phase shift masks are manufactured for each of a plurality of final mask patterns, mask patterns other than the fine pattern can be formed into a plurality of phase shift masks without imparting a phase difference. By arranging, a mask pattern for eliminating unnecessary patterns other than the fine pattern is formed by being incorporated in the phase shift mask. For this reason, a mask used for normal exposure that eliminates unnecessary patterns becomes unnecessary, and the number of masks can be reduced accordingly, and the number of exposures can be reduced accordingly.

Further, according to the method of manufacturing a high resolution mask according to the ninth aspect, a step of forming an initial mask pattern based on predetermined pattern data, and a step of exposing the initial mask pattern to a depth of focus and an exposure for exposure. A step of dividing into a plurality of types of mask patterns on the basis of the pattern shape and the pattern density based on the data regarding the margin of the amount; a step of creating a plurality of final mask patterns for each of the plurality of types of mask patterns; For each final mask pattern, having a step of producing a plurality of high-resolution masks, so that it is possible to secure a sufficient depth of focus and a sufficient amount of exposure at the time of exposure. A plurality of final mask patterns are extracted by extracting a mask pattern having a pattern shape and a pattern density from an initial mask pattern. And a plurality of high-resolution masks for forming a one-layer resist pattern corresponding to the plurality of final mask patterns. When a multiple-exposure process is performed using a high-resolution mask to form a resist pattern of one layer, it is possible to secure a sufficient depth of focus and a sufficient amount of exposure for each of the multiple-exposure processes. . Accordingly, a high-resolution mask capable of easily securing the optimum exposure conditions and increasing the lithography process latitude can be manufactured.

According to the method for forming a resist pattern according to the eleventh aspect, the step of manufacturing a plurality of phase shift masks by using the method for manufacturing a high resolution mask according to the seventh aspect includes the steps of: Performing a multiple exposure process using a phase shift mask to form a one-layer resist pattern to which a plurality of final mask patterns have been transferred. Since a one-layer resist pattern is formed by multiple exposure processing using a shift mask, the pattern shape controllability and transfer position accuracy of the resist pattern can be improved. In addition, when performing multiple exposure processing using a plurality of phase shift masks, it is possible to set optimal optical conditions for each of them, so that the latitude of the lithography process can be increased. Therefore, manufacturing yield and reliability can be improved, and throughput can be increased.

According to the resist pattern forming method of the twelfth aspect, multiple exposure processing is performed by using a plurality of phase shift masks manufactured by applying the high resolution mask manufacturing method of the eighth aspect. Forming a one-layer resist pattern to which a plurality of final mask patterns have been transferred, so that a mask pattern for eliminating unnecessary patterns other than the fine pattern is incorporated in the phase shift mask. Since a one-layer resist pattern is formed using a shift mask, a mask used for normal exposure for eliminating unnecessary patterns becomes unnecessary, and the number of masks can be reduced accordingly. The number of exposures can be reduced.

According to the method for forming a resist pattern according to the thirteenth aspect, the step of manufacturing a plurality of high-resolution masks by using the method of manufacturing a high-resolution mask according to the ninth aspect includes the steps of: Performing a multiple exposure process using a high-resolution mask to form a one-layer resist pattern to which a plurality of final mask patterns have been transferred, thereby ensuring a sufficient depth of focus and a sufficient amount of exposure for each. A single-layer resist pattern is formed by multiple exposure processing using a plurality of high-resolution masks, so that each exposure processing using each high-resolution mask requires a sufficient depth of focus and exposure amount. And the optimal optical conditions can be set for each high-resolution mask. Therefore, it is possible to easily secure the optimum exposure condition and increase the lithography process latitude. In addition, when performing multiple exposure processing using a plurality of high-resolution masks, it is possible to set optimal optical conditions for each of them, so that it is possible to increase the margin of the lithography process. Therefore, manufacturing yield and reliability can be improved, and throughput can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a Levenson phase shift mask pattern creation device according to a first embodiment of the present invention.

FIG. 2 is a schematic block diagram showing a Levenson phase shift mask manufacturing apparatus incorporating the mask pattern forming apparatus of FIG.

FIG. 3 shows the pattern shape and pattern of the fine pattern of the initial mask pattern created by the first mask pattern creating unit 21 of the Levenson phase shift mask manufacturing apparatus of FIG. FIG. 4 is a plan view showing a plurality of types of mask patterns divided based on density.

FIG. 4 is a plan view schematically showing a plurality of final mask patterns created by a second mask pattern creating section 24 of the Levenson phase shift mask manufacturing apparatus of FIG. 2;

FIG. 5 is a view showing a plurality of Levenson phase shift masks produced by the Levenson phase shift mask producing unit for each of a plurality of final mask patterns produced by the Levenson phase shift mask pattern producing unit of the apparatus for producing the Levenson phase shift mask of FIG. It is a schematic sectional drawing which shows a part.

FIG. 6 is a schematic block diagram illustrating a mask pattern creating apparatus for a high-resolution mask according to a second embodiment of the present invention.

FIG. 7 is a schematic block diagram illustrating a high-resolution mask manufacturing apparatus incorporating the mask pattern generating apparatus of FIG. 6;

8 is a diagram showing the initial mask pattern created by the first mask pattern creating unit 71 of the high-resolution mask manufacturing apparatus shown in FIG. 7; 11 is a graph showing ED windows for a plurality of types of mask patterns divided based on a pattern shape and a pattern density.

FIG. 9 is a schematic sectional view showing a conventional Levenson phase shift mask.

FIG. 10 is a schematic sectional view showing a conventional Levenson phase shift mask.

FIG. 11 is a graph showing an ED window for a conventional Levenson phase mask pattern.

[Description of Signs] 11 ... pattern data input unit, 12 ... loading data input unit, 20 ... Levenson phase shift mask pattern creation unit, 21 ... first mask pattern creation unit,
22: pattern dividing section, 23: binary mask pattern creating section, 24: second mask pattern creating section, 3
0: Levenson phase shift mask producing unit, 31: pattern drawing unit, 32: light shielding film etching unit, 33:
Quartz substrate etching section, 34 cleaning section, 35 line width / phase difference measurement section, 36 defect correction section, 41, 42
..., 43 ..., 44 ..., 51 ..., 53 ... quartz substrate, 54a, 54b, ..., 54f ... light shielding film, 55, 5
6, 58, digging, 61 pattern data input unit, 62 depth of focus and exposure tolerance data input unit, 70 high resolution mask pattern creation unit, 71
1st mask pattern creation section, 72... Pattern division section, 73... 2nd mask pattern creation section, 80... High-resolution mask creation section, 81... Pattern drawing section, 82.
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6. Defect correction unit.

Claims (14)

[Claims] An apparatus for creating a mask pattern of a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction, wherein predetermined pattern data is input. A pattern data input unit; a loading data input unit for inputting data relating to a loading effect when etching a transparent portion of the transparent substrate in the phase shift mask to form a digging; and a predetermined pattern input to the pattern data input unit. A first mask pattern creating unit for creating an initial mask pattern based on the data, and the initial mask pattern created by the first mask pattern creating unit, based on data on a loading effect input to the loading data input unit. , Pattern shape and pattern density And a second mask pattern creating unit that creates a plurality of final mask patterns for each of the plurality of types of mask patterns divided by the pattern dividing unit. An apparatus for producing a mask pattern. 2. An apparatus for creating a mask pattern of a high-resolution mask, comprising: a pattern data input unit for inputting predetermined pattern data; And a tolerance data input unit for the amount of exposure, a first mask pattern creation unit that initially creates a mask pattern based on predetermined pattern data input to the pattern data input unit, and a first mask pattern creation unit. For the created initial mask pattern, based on the data on the depth of focus and the latitude of the exposure amount input to the depth of focus and latitude of the exposure amount data input unit, a plurality of types of mask patterns based on the pattern shape and the pattern density. And a plurality of types of cells divided by the pattern dividing unit. For each pattern, creation device of a mask pattern and having a second mask pattern creating section that creates a plurality of final mask pattern. 3. The mask pattern creating apparatus according to claim 2, wherein the plurality of final mask patterns created by the second mask pattern creating section are each formed of light transmitted through both sides of the fine pattern in the fine line width direction. An apparatus for creating a mask pattern, wherein the mask pattern is a phase shift mask pattern that improves resolution by using an interference effect due to a phase difference. 4. An apparatus for manufacturing a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light transmitted through both sides of a fine pattern in a fine line width direction, the pattern data inputting inputting predetermined pattern data. A loading data input unit for inputting data relating to a loading effect when forming a digging by etching a transparent portion of a transparent substrate in a phase shift mask; and based on predetermined pattern data input to the pattern data input unit. A first mask pattern creating section for creating an initial mask pattern; and a pattern shape of the initial mask pattern created in the first mask pattern creating section, based on data on a loading effect input to the loading data input section. And multiple types based on pattern density A pattern division unit for dividing into mask patterns; a second mask pattern creation unit for creating a plurality of final mask patterns for each of the plurality of types of mask patterns divided in the pattern division unit; And a phase shift mask producing section for producing a plurality of phase shift masks for each of the plurality of final mask patterns produced in the section. 5. A pattern data input unit for inputting predetermined pattern data, a depth of focus and exposure latitude data input unit for inputting data relating to a depth of focus and exposure latitude during exposure, and the pattern A first mask pattern creating unit that creates an initial mask pattern based on predetermined pattern data input to a data input unit; and the depth of focus and exposure for the initial mask pattern created by the first mask pattern creating unit. A pattern dividing unit that divides into a plurality of types of mask patterns based on a pattern shape and a pattern density based on the data regarding the depth of focus and the latitude of the exposure amount input to the amount tolerance data input unit; and the pattern dividing unit. Creating a plurality of final mask patterns for each of the plurality of types of mask patterns divided in 2, and a high-resolution mask manufacturing unit that manufactures a plurality of high-resolution masks for each of the plurality of final mask patterns created in the second mask pattern creating unit. High resolution mask manufacturing equipment. 6. The apparatus for manufacturing a high-resolution mask according to claim 5, wherein the plurality of high-resolution masks manufactured in the mask manufacturing section are positioned at positions of light transmitted through both sides of the fine pattern in the fine line width direction. An apparatus for manufacturing a high-resolution mask, which is a phase shift mask that improves resolution by using an interference effect due to a phase difference. 7. A method of manufacturing a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction, the mask pattern being initially formed based on predetermined pattern data. And, for the initial mask pattern, based on the data on the loading effect when forming the digging by etching the transparent portion of the transparent substrate in the phase shift mask,
Dividing into a plurality of types of mask patterns based on the pattern shape and the pattern density; forming a plurality of final mask patterns for each of the plurality of types of mask patterns; Producing a phase shift mask, and a method for producing a high resolution mask. 8. The method of manufacturing a high-resolution mask according to claim 7, wherein a mask pattern other than a fine pattern is provided with a phase difference when manufacturing a plurality of phase shift masks for each of the plurality of final mask patterns. A method of manufacturing a high-resolution mask, wherein the mask is arranged on the plurality of phase shift masks without performing the process. 9. A step of creating an initial mask pattern based on predetermined pattern data; and, for the initial mask pattern, determining a pattern shape and a pattern density based on data relating to a depth of focus and an exposure allowance at the time of exposure. Dividing a plurality of types of mask patterns as a reference; forming a plurality of final mask patterns for each of the plurality of types of mask patterns; and fabricating a plurality of high-resolution masks for each of the plurality of final mask patterns. A method for manufacturing a high-resolution mask, comprising: 10. The method of manufacturing a high-resolution mask according to claim 9, wherein the plurality of high-resolution masks manufactured for each of the plurality of final mask patterns penetrate both sides of the fine pattern in the fine line width direction. A method for manufacturing a high-resolution mask, which is a phase shift mask for improving resolution using an interference effect due to a phase difference of light. 11. A method for forming a resist pattern using a high-resolution mask for improving resolution by using an interference effect due to a phase difference of light passing through both sides of a fine pattern in a fine line width direction, the method comprising: Based on the initial mask pattern, the initial mask pattern, based on the data on the loading effect when etching the adjacent transparent portion of the transparent substrate in the phase shift mask to form a digging of different depth, And dividing into a plurality of types of mask patterns based on the pattern density, creating a plurality of final mask patterns for each of the plurality of types of mask patterns, and fabricating a plurality of phase shift masks for each of the plurality of final mask patterns. Performing a multiple exposure process using the plurality of phase shift masks. There, a resist pattern forming method characterized by comprising the steps of: forming a resist pattern of one layer which has been transferred a plurality of final mask pattern. 12. The resist pattern forming method according to claim 11, wherein a mask pattern other than a fine pattern is provided with a phase difference when producing a plurality of phase shift masks for each of the plurality of final mask patterns. Arranged on the plurality of phase shift masks, a mask pattern other than the fine pattern is subjected to multiple exposure processing using a plurality of phase shift masks arranged without imparting a phase difference, and the plurality of final masks A method of forming a resist pattern, comprising forming a one-layer resist pattern onto which a pattern has been transferred. 13. A method of forming a resist pattern using a high-resolution mask, comprising: forming an initial mask pattern based on predetermined pattern data; Based on the data on the degree, divided into a plurality of types of mask patterns based on the pattern shape and pattern density, for each of the plurality of types of mask patterns, to create a plurality of final mask patterns, for each of the plurality of final mask patterns, Producing a plurality of high-resolution masks; and performing a multiple exposure process using the plurality of high-resolution masks to form a one-layer resist pattern obtained by transferring the plurality of final mask patterns. A method for forming a resist pattern. 14. The resist pattern forming method according to claim 13, wherein the plurality of high-resolution masks produced for each of the plurality of final mask patterns are formed of light transmitted through both sides of the fine pattern in the fine line width direction. A method of forming a resist pattern, wherein the method is a phase shift mask that improves resolution by using an interference effect due to a phase difference.