JPH03125150A - Mask and mask preparation - Google Patents

Abstract

PURPOSE:To improve the contrast of a projected optical image for transfer mask patterns of various shapes and to form a resist pattern excellent in cross- selectional shape by using a phase shift mask arranged directly next to at least one of transmissive areas so that lights which have passed through a mask differ by about 180 deg. from each other in phase. CONSTITUTION:A pair of light transmitting areas is provided; the pair is arranged so that both the areas are in contact with each other; at least one of them is provided with a means 12 for making lights which have passed through their respective light transmitting areas almost 180 deg. different from each other in phase. In this case, the phase of the light which has passed through the light transmitting area and that of the light which has passed through a phase shifter are offset by shifting the phases almost 180 deg. from each other, at their boundary part; consequently light intensity is extremely decreased. That is, the light-shielding effect which is far more intense can be obtained in such a mask. Thus, a satisfactory optical image of high contrast can obtained for an arbitrary linear pattern.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a projection exposure mask used for forming fine patterns in various solid-state devices such as semiconductor devices, superconductor devices, magnetic devices, and optical ICs, and a method for manufacturing the same.

[Conventional technology]

Conventionally, the formation of fine patterns for solid-state devices such as VLSI
This has mainly been done using the reduction projection exposure method. The above method uses a projection optical system to form an image of the mask pattern onto a substrate coated with a resist, thereby transferring the mask pattern. The critical resolution in the reduction projection exposure method is proportional to the exposure wavelength λ and inversely proportional to the numerical aperture NA of the projection optical system. Therefore, improvements in resolution have been promoted by shortening the wavelength of exposure light and increasing the NA of projection lenses. However, increasing the resolution using the above method is approaching its limits due to limitations in the design of the projection optical system, manufacturing technology, and light source. On the other hand, as one way to overcome these limitations. There is a method (hereinafter referred to as the phase shift method) that aims to improve resolution and increase the depth of focus by introducing a phase difference between the lights that have passed through adjacent transparent parts on the mask. For example, it is described in Japanese Patent Laid-Open No. 58-173744. For example, in the case of a repeating pattern of elongated transmissive areas and opaque areas, this method is applied at every other transmissive area so that the phase difference of light passing through adjacent transmissive areas on the mask is approximately 180 degrees. A transparent material (hereinafter referred to as a 1-phase shifter) is provided for introducing a phase difference. It has been reported that in the case of the above pattern, the resolution is improved by about 40% compared to the case where no phase thick is provided. The above facts can be found in, for example, IE Transactions on Electron Devices, E.D.-29, No. 12 (1982) No. 1828.
From page to page 1836 (■EEE, Trans, Elec
tron Devices, ED29. No.12
(1982) pp 1828-1836).

[Problem to be solved by the invention]

The above-mentioned conventional technology has a problem in that it can only be applied to a certain specific shape of a button, in which a transparent area and an opaque area are repeatedly arranged. Further, in the above-mentioned conventional technology, the plurality of transmission regions having a phase difference of 180 degrees must be separated from each other. When forming such mutually separated patterns, it is necessary to use a negative resist, and there is a problem in that it is difficult to apply a positive resist, which is mainly used in the current LSI manufacturing process. . An object of the present invention is to provide a mask that solves the above-mentioned problems, improves the contrast of projected optical images of transfer patterns of various shapes, and makes it possible to form battens with good shapes. Another object of the present invention is to provide a method for manufacturing the above mask. (Means for Solving the Problems) The above object is to provide (1) a mask having a mask pattern for projection exposure using a projection optical system, having at least one pair of light transmitting regions, The light transmitting regions are arranged so as to be in contact with each other, and at least one of the pair of light transmitting regions has means for making the phases of the light passing through the respective light transmitting regions different from each other by approximately 180 degrees. (2) The mask has an opaque region, and one of the pair of light-transmissive regions is disposed substantially in contact with and around the opaque region, as described in 1 above. mask, (3) the width of one of the pair of light transmission areas is λ/NA (where λ is the wavelength of the light for the projection exposure, and NA is the numerical aperture of the projection optical system);
The mask according to item 1 above, wherein the mask is as follows, and the one light-transmitting region is arranged within the other light-transmitting region, (4) the mask of the above-mentioned pair of light-transmitting regions is The means to make the phases differ from each other by approximately 180 degrees is as follows:
The material is transparent to exposure light, and the refractive index n and thickness d of the transparent material are (n-1)d=Φλ (where Φ is 5/12≦Φ≦7/12 A range of values, λ
is the wavelength of the light used for projection exposure; (5) the transparent material is an organic polymer compound, silicon oxide, silicon nitride, magnesium fluoride; , the mask according to 4 above, which is made of at least one of calcium fluoride, indium oxide, and tin oxide; (6) a transparent film, an opaque film, and a resist film having a predetermined thickness are laminated on the substrate; Process. A step of forming the resist film into a predetermined resist pattern, a step of etching the opaque film using the resist pattern as a mask to form a light-shielding button, removing the resist pattern, depositing a film on the entire surface, and removing the film. A step of anisotropic etching to leave the film of a predetermined width only on the side wall portion of the light-shielding pattern to form a side wall batten; a step of etching the transparent film using the side wall batt and the opaque film as a mask; 2. The mask manufacturing method as described in 2 above, which includes the step of removing the film on the side wall portion, (7) laminating an opaque film and a resist film of a predetermined thickness on the substrate, and depositing the resist film in a predetermined thickness. forming a resist pattern, etching the opaque film using the resist pattern as a mask to form a light-shielding pattern, removing the resist pattern, depositing a film over the entire surface, and anisotropically etching the film. 2. The method for manufacturing a mask according to the above 2, characterized in that the method includes the step of forming a side wall batten by leaving the coating with a predetermined radius only on the side wall portion of the light shielding batten; (8) forming a predetermined film on the substrate; A step of laminating a thick transparent film, an opaque film, and a resist film, a step of forming the resist film into a predetermined resist pattern, a step of etching the opaque film using the resist pattern as a mask, and a step of etching the opaque film on the removed portion of the opaque film. Item 2 above, characterized in that the method includes the steps of etching the exposed transparent film, and removing the outline of the opaque film so that the transparent film is exposed over a predetermined width along the outline of the opaque film. (9) a step of laminating an opaque film and a resist film on a substrate; a step of forming the resist film into a predetermined resist pattern; a step of etching the opaque film using the resist pattern as a mask; a step of etching the substrate exposed in the portion from which the opaque film has been removed to a predetermined depth; Achieved by the method for manufacturing a mask according to the above item 2, which includes the step of removing the contour of the opaque film so that the unetched portion of the substrate is exposed to a predetermined width along the contour of the opaque film. . In the present invention, as a means for making the phases of light passing through a pair of light transmission regions different from each other by approximately 180 degrees,
For example, a material transparent to exposure light having a predetermined thickness as described in item 5 above is used. Further, even if a common material is present in the circumferential regions, if the thickness of each region differs by a predetermined thickness, it is recognized that the above means exists.

[Operations] Figure 1(a) shows a partial cross-section of a mask that has two transmission regions (hereinafter referred to as the first transmission region and the second transmission region) in which the phases of transmitted light differ by 180 degrees from each other. FIGS. 1(b) and 1(c) show the phase of the light after passing through the mask and the light intensity on the substrate at the connecting portion where the two passing regions directly communicate with each other. It can be seen that the phases of the light that has passed through the two transmission regions cancel each other out at the boundary between the two, thereby significantly weakening the light intensity. This principle can be applied to various mask patterns such as: Figures 2 (a), (b), and (c) show the cross section of the mask when phase shifters with minute widths are provided on both sides of the opaque area of the line-and-space pattern, the phase of the light immediately after passing through the mask, and the surface of the substrate. This shows the light intensity at . Further, FIG. 3 shows a cross section of a conventional mask without a phase shifter, and the phase and light intensity of light corresponding to the above. A comparison between Figures 2 and 3 shows that by providing a phase shifter with a minute width at the boundary between the transparent and opaque areas of the mask, a good optical image with higher contrast can be obtained in the line-and-space pattern. . Since this method can be applied to patterns of arbitrary shapes, there are no restrictions on the resist process, pattern layout, etc., and this effect can be observed even at a position where the substrate is shifted from the focal point position in the optical axis direction. FIG. 4 shows the cross section of a mask, the phase of light immediately after passing through the mask, and the light intensity on the substrate when a band-shaped phase shifter with a width of λ/NA or less is arranged in the transmission region. Furthermore, FIG. 5 similarly shows the case where a band-shaped opaque region having the same width as FIG. 4 is arranged in the transparent region instead of a phase shifter. As shown in Fig. 4, although the mask is composed of only a transparent area, the same light-shielding effect as when the second transparent area in which a phase difference is introduced is an opaque area is obtained. . Moreover, in contrast to the conventional mask shown in FIG. 5 in which the light intensity at the light-shielding portion does not become completely zero, the mask according to the present invention can provide a stronger light-shielding effect. Therefore, by using the mask according to the present invention, a good optical image with high contrast can be obtained for any linear pattern. Figure 6 shows the cross section of the mask, the phase of light immediately after passing through the mask, and the light intensity on the substrate when band-shaped phase shifters with dimensions larger than the resolution limit are periodically arranged in the transmission region. It is. As shown in FIG. 6, it can be seen that the light intensity becomes zero here even though there is no opaque region near the boundary between the first transmission region and the second transmission region. That is, the boundary can be used as a light shielding pattern. Also,
It can be seen that in case 4, the period of light intensity on the substrate is twice the period of the mask pattern. Therefore, an extremely fine line and space pattern can be formed. All of the above effects are caused by the phase of the light passing through the transmission region and the phase of the light passing through the phase shifter, as in Figure 1. This is due to the fact that they are shifted by approximately 180 degrees at the boundary between the two, which cancels each other out and significantly weakens the light intensity. [Examples] The present invention will be described in detail below using examples. Example I A line and space pattern as shown in FIG. 2 was transferred using an i-line (wavelength 365 nm) reduction projection exposure apparatus with a reduction ratio of 10:1 and a projection optical system with NA=0.42. Ta. Here, the period of the pattern was 1.2 μm, and the width of the phase shifter at both ends of the light-shielding region and the width of the light-shielding region were 0.05 μm and 0.5 μm, respectively. Therefore,
The above widths on the mask are 0.5 μm and 5.0 μm, respectively.
m. The widths of the light shielding area and the area where the phase shifter is arranged are not necessarily limited to the above values. However, the width of the phase shifter is preferably equal to or less than the resolution limit of the conventional mask. Next, the mask manufacturing process according to this example will be described using FIG. First, a silicon nitride film 2 with a thickness of 1100 nm and a silicon oxide film 3 with a thickness of 420 nm were sequentially deposited on a synthetic quartz substrate 1.
A chromium film 4 was deposited to a thickness of 80 nm and a chromium film 4 was deposited to a thickness of 80 nm, both by vapor deposition (FIG. 7a). Here, silicon nitride film 2. Silicon oxide film 3. The chromium film 4 is used as a stopper film, a single phase shifter film, and an opaque film in the etching of the single phase shifter. Here, silicon oxide was used as the material for the phase shifter film, but organic polymer films transparent to exposure light such as resists, silicon nitride, etc.
Magnesium fluoride, lithium fluoride, SOG, etc. may also be used. Further, although a chromium film is used as the opaque film, a molybdenum silicide film or the like may also be used. Further, the etching stopper film is not limited to the silicon nitride film, and it is also possible to omit it. Furthermore, in addition to these films, a transparent conductive film or the like may be laminated. Generally, the optimum value of the film thickness of the phase shifter is determined by the following equation. d=λ/2(n-1) In this example, λ is the exposure wavelength of 365 nm, and n is the refractive index of the silicon oxide film on the wavelength side of 1.43. According to the above formula, it is preferable that the thickness of the silicon oxide film serving as the one-phase shifter is approximately 424±10 nm. Negative resist RD200ON (Hitachi Chemical,
(product name) was applied, and a predetermined light-shielding pattern area was drawn using an electron beam drawing device. In this example, RD200ON
(Hitachi Chemical, product name) was used, but another resist may be used. After a resist pattern was formed by drawing and a prescribed resist development process, the chromium film 4 was wet-etched using a prescribed etching solution using this as a mask. Thereafter, the resist was further removed to obtain a predetermined chrome pattern 5 (FIG. 7b). next,
A uniform silicon nitride film 6 is coated on the entire surface of the mask by the plasma CVD method (FIG. 7c), and then the film is anisotropically dry etched in the film thickness direction to a thickness of approximately 0.5 μm only on the side walls of the chromium pattern. The above-mentioned film having a width of
). Here, instead of the silicon nitride film 6, a resist,
A coating film such as SOG may be used, or it may be formed using a method such as CVD or vapor deposition. Next, using the sidewall pattern 7 made of silicon nitride and the chromium pattern 5 as masks, the silicon oxide film was anisotropically dry etched (FIG. 7e). After that, the side wall pattern 7 is removed by dry etching to form a chrome pattern 5.
The surface of the silicon oxide film 3 was exposed at the contour part, and a desired phase shift mask was obtained (FIG. 7f). After forming the chromium pattern 5, the silicon oxide film 3 is removed by anisotropic dry etching using the chromium pattern or the resist pattern used in forming the chromium pattern as a mask, and then a small amount of the chromium film is isotropically etched. The silicon oxide film 3 may be exposed at the contour of the chromium pattern 5 by etching. In addition, when performing this method, it is preferable that the resist film used as a mask when forming the chromium pattern is not removed until the chromium film is isotropically etched. Note that the method for manufacturing the phase shift mask is not limited to the one described above, and other known methods may be used. For example, the film itself left on the side wall of the chrome pattern may be used as a phase shifter. Alternatively, the phase shifter may be formed by etching a synthetic quartz substrate to a predetermined depth without using a transparent film. The phase shift mask thus produced was transferred onto a resist film coated on a silicon substrate using the reduction projection exposure apparatus. For comparison, a line-and-space pattern of the same size was also transferred using a conventional mask. In this example, TSMR8900 is used as a resist.
(Tokyo Ohka, product name), but other resists may be used. Also, in this example, the coherence factor value was 0.5, but other values may be used. After exposure, a prescribed development process was performed to form a resist pattern on the substrate. As a result of observing the formed resist pattern using a scanning electron microscope (SEM), it was found that the pattern had a more vertical cross-sectional shape when using the mask according to the present invention than when using a conventional mask. was able to form. Furthermore, the exposure latitude was improved by about 30%. Furthermore, ±1.5 μm around the focal point position
A depth of focus of approximately Example 2 A chromium film and a resist film of a predetermined thickness were formed on a synthetic quartz substrate using the same method as in Example 1, but without forming a silicon nitride film or a silicon oxide film. Furthermore, the same steps as in Example 1 were carried out up to the formation of sidewall patterns, and this silicon nitride sidewall pattern was used as a phase shifter film. When the produced phase shift mask was transferred onto a resist film coated on a silicon substrate using a reduction projection exposure apparatus, almost the same results as in Example 1 were obtained. Example 3 g with a reduction ratio of 5:1 with a projection optical system of NA=0.54
1.0 using a line reduction projection exposure device (wavelength 436 nm)
μm period LSI wiring pattern and GaAs MOSF
Figure 8 shows the arrangement of the mask light-shielding pattern and phase shifter used in this example, where the ET gate pattern was transferred.
The dimensions shown in a) and (b), however, are the values on a wafer that has been reduced to one-fifth. In the mask according to this embodiment, the gate and wiring portions are mainly It consists of only a phase shifter without providing an opaque region. That is, it is based on the principle shown in FIG. Here, the width of 1 phase shifter 12 is 0.2 μm (on the wafer)
Although the width is not limited to 0.2 μm, it is preferably less than the resolution limit of a conventional mask.A light-shielding pattern 14 is provided at the pad portion 15 at the end of the wiring. A narrow phase shifter 12 is arranged at the outline of the light shielding pattern 14. Further, the thickness of the silicon oxide which is the phase shifter is λ=438 nm, n
=1.42, it is preferable to set it to approximately 519±10 nm. Next, the mask manufacturing process will be described. First, as in Example 1, a silicon nitride film, a silicon oxide film, and a chromium film were sequentially laminated on a synthetic quartz substrate. However, the thickness of silicon oxide was 520 nm. Here, the silicon nitride film, silicon oxide film, and chromium film are
Each of these is used as a stopper film, a phase shifter film, and an opaque film in phase shifter etching. A negative resist RD200ON (Hitachi Chemical, product name) was applied onto the substrate, and predetermined light-shielding areas were drawn using an electron beam drawing device. After that, a prescribed resist development process was performed to form a resist pattern, and then the chromium film was wet-etched using this as a mask to form a chrome pattern on the pad area. After drawing the pattern of the phase shifter 12 of the gate and wiring portion shown in FIG. 8 using a drawing device, a prescribed resist development process was performed to form a resist pattern. moreover,
The silicon oxide film is wet-etched using the pattern as a mask to form the phase shifter 12 on the gate or wiring portion.Next, the chromium pattern on the pad portion is isotropically etched by wet etching to form the above-mentioned phase shifter 12. The silicon oxide film was exposed on the contour of the chrome pattern to obtain a desired phase shift mask. Note that the method for manufacturing the phase shift mask is not limited to the one described above, and other known methods may be used. The phase shift mask produced in this way was transferred onto a resist film coated on a silicon substrate using the reduction projection exposure apparatus.
8900 (Tokyo Ohka, product name) was used, but another resist may be used. After exposure, a prescribed development process was performed to form a resist pattern on the substrate. As a result of scanning the formed resist pattern using a scanning electron microscope (SEM), it was possible to form the wiring pattern with a good shape and cross-sectional shape. Also, ± around one in-focus position
A depth of focus of about 1.0 μm was obtained. For comparison, similar exposure was performed using a conventional mask in which all the phase shifter portions of this example were replaced with light-shielding patterns (opaque areas), but the resist pattern was not resolved at all. Example 4 Using a KrF excimer laser stepper (wavelength 248 nm) having a projection optical system with NA=0.35, a 0.2 μm line-and-space pattern (period 0.4 μm) was created based on the principle shown in FIG. The transcription was carried out. That is, in the mask according to this embodiment, the boundary between the normal light shielding part and the phase shifter is used as the light shielding part. Therefore, the period of the line-and-space pattern formed on the wafer is half the period of the phase shifter pattern arranged on the wafer. Therefore, we changed the phase shifter from 0.4 μm on the wafer to 0.8 μm.
Arranged in cycles. Next, the mask manufacturing process will be explained using FIG. 9. First, 20 silicon nitride films 2 are sequentially deposited on a synthetic quartz substrate 1.
A silicon oxide film 3 was deposited to a thickness of 260 nm by vapor deposition. Here, silicon nitride film 2. The silicon oxide film 3 is used as a stopper film and a phase shifter film in the etching of the phase shifter, respectively. The thickness of the silicon oxide film 3 used as the phase shifter is:
In the formula described in Example 1, λ=248 nm, n=1.
48, preferably about 260±10 nm. A negative resist RD200ON (Hitachi Chemical, product name) was coated on the above substrate, and an area where one phase shifter would be placed was drawn using an electron beam lithography system.
00ON (Hitachi Chemical, product name) was used, but other negative or positive resists may be used. After drawing,
A resist pattern 8 was formed by performing a prescribed resist development process. Thereafter, the silicon oxide film was wet-etched using the resist pattern 8 as a mask, and the resist pattern 8 was further removed to form a one-phase shifter 9. As a result, a desired phase shift mask was obtained. Note that the method for manufacturing the phase shift mask is not limited to the one described above, and other known methods may be used. For example, the resist pattern itself may be used as a phase shifter without using a silicon oxide film, or the phase shifter may be formed by etching a synthetic quartz substrate to a predetermined depth. The phase shift mask thus produced was applied to a chemically amplified negative resist 5AL-601 (Sibley, product name) coated on a silicon substrate using the stepper.
The above pattern was transferred. For comparison, a line and space pattern with the same period was also transferred using a conventional mask. In this embodiment, the value of the coherence factor is set to 0.3, but other values may be used. Further, in this embodiment, a chemically amplified negative resist 5AL-601 (manufactured by Sibley Co., Ltd., product name) was used, but other resists may be used. After exposing the above pattern under predetermined exposure conditions,
Balancing was performed after a predetermined exposure. Thereafter, a prescribed development process was performed to form a resist pattern. As a result of observing the formed resist shape using a scanning electron microscope (SEM), when a conventional mask was used, the above pattern was not resolved at all. In contrast, when using the mask according to the present invention. The above pattern could be formed in a good shape. Further, a depth of focus of about ±1 μm was obtained around one in-focus position. Example 5 An isolated wiring pattern as shown in FIG. 11 was transferred using a KrF excimer laser stepper (wavelength 248 nm) having a projection optical system with NA=0.35. This mask manufacturing process will be explained using FIG. 10. First, a chromium film 4 is sequentially deposited on a synthetic quartz substrate 1 to a thickness of 80 mm.
A chromium film 4 is used as an opaque film (FIG. 10(a)). A negative resist RD200ON (Hitachi Chemical, product name) was coated on the above substrate, and predetermined light-shielding regions were drawn using an electron beam lithography system.
Although N (Hitachi Chemical, product name) was used, another resist may be used. After drawing, a predetermined resist development process was performed to form a resist pattern 8. Thereafter, using the resist pattern 8 as a mask, the chromium film was wet-etched using a mixed acid (FIG. 10(b)). Next, the synthetic quartz substrate 1 is wet-etched using an etching solution prepared by diluting cyclohydric acid 60 times with ammonium cyclide. (FIG. 10 (Q)). In this example, since a synthetic quartz substrate is used as a phase shifter, the etching depth of one synthetic quartz substrate is λ=248 nm, n: 1.4
8, it was set to 260 nm. Here, since the etching rate of the synthetic quartz substrate with the above-mentioned etching solution is 20 nm/sec, the etching time was set to about 1300 seconds, and the chromium film was wet-etched again using a mixed acid. Figure 10(d)). Here, in order to expose the patterned synthetic quartz substrate to a width of 0.5 μm on the contour of the chrome pattern 5, etching was performed for about 20 seconds at an etching rate of 25 nm/sec for the chromium film. Thereafter, the resist pattern 8 was removed to obtain a desired phase shift mask (FIG. 10(e)). Note that the method for manufacturing the phase shift mask is not limited to the one described above, and other known methods may be used. The phase shift mask thus produced was applied to a chemically amplified negative resist 5AL-601 (Sibley, product name) coated on a silicon substrate using the stepper.
The above batan was transcribed. For comparison, the same pattern was also transferred using a conventional mask. In this example, the coherence factor value was set to 0.3, but other values may be used. In this example, a chemically amplified negative resist 5AL-601 (Sibley Co., Ltd. product name) was used, but other resists may also be used. Post-baking and development were performed to form a resist pattern. As a result of observing the formed resist shape using a scanning electron microscope (SEM), it was found that the batten was formed with a more vertical cross-sectional shape when using the mask according to the present invention compared to when using a conventional mask. We were able to. Further, a depth of focus of approximately ±1 μm was obtained with one in-focus position as the center. (Effects of the Invention) According to the present invention, at least one pair of transmission regions in which the phases of light after passing through a mask are different from each other by approximately 180 degrees,
By using phase shift masks placed directly adjacent to each other, it was possible to improve the contrast of projected optical images for transfer mask patterns of various shapes, and to form resist patterns with excellent cross-sectional shapes.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the principle operation of the present invention, and Fig. 2, Fig. 4, and Fig. 6 respectively show the cross-sectional shape of a mask pattern of one embodiment of the present invention and the phase of light immediately after passing through the mask. 3 and 5 are schematic diagrams showing the cross-sectional shape of a conventional mask pattern, the phase of light immediately after passing through the mask, and the light intensity on the substrate, respectively. , FIG. 7, FIG. 9, and FIG. 10 are process diagrams showing an example of the manufacturing process of a phase shift mask that is an embodiment of the present invention, and FIG. 8 and FIG. FIG. 3 is a layout diagram of a mask pattern in one embodiment. 1...Synthetic quartz substrate 3...Silicon oxide film 5...Chromium pattern 8...Resist pattern 11...Substrate 2.6...Silicon nitride film 4...Chromium film 7...Side wall Button 9.12... Phase shifter 13... Opaque film 14... Light shielding button 15... Pad portion 22... Bang

Claims (1)

[Claims] 1. A mask having a mask pattern for projection exposure using a projection optical system, which has at least a pair of light transmitting regions, and the pair of light transmitting regions are arranged so as to be in contact with each other. 2. A mask comprising, in at least one of the pair of light transmitting regions, a means for making the phases of light that has passed through each of the light transmitting regions different from each other by approximately 180 degrees. 2. The mask according to claim 1, wherein the mask has an opaque region, and one of the pair of light transmitting regions is disposed substantially in contact with and around the opaque region. 3. The width of one of the pair of light transmission areas is less than or equal to λ/NA (where λ is the wavelength of the projection exposure light, and NA is the numerical aperture of the projection optical system), and 2. The mask according to claim 1, wherein the light transmitting region is located within the other light transmitting region. 4. The means for making the phases of the light passing through the pair of light transmission regions different from each other by approximately 180 degrees is a material that is transparent to the exposure light, and the refractive index n and thickness of the transparent material d is (n-1)d=Φλ (where Φ is a value in the range of 5/12≦Φ≦7/12, λ
2. The mask according to claim 1, wherein: is the wavelength of the light for projection exposure. 5. The mask according to claim 4, wherein the transparent material is a material consisting of at least one of an organic polymer compound, silicon oxide, silicon nitride, magnesium fluoride, calcium fluoride, indium oxide, and tin oxide. 6. A step of laminating a transparent film, an opaque film, and a resist film of a predetermined thickness on a substrate, a step of forming the resist film into a predetermined resist pattern, and a step of etching the opaque film using the resist pattern as a mask to shield light. a process of forming a pattern;
removing the resist pattern, depositing a film over the entire surface, and anisotropically etching the film to leave the film of a predetermined width only on the sidewalls of the light-shielding pattern to form a sidewall pattern; 3. The method of manufacturing a mask according to claim 2, further comprising the steps of: etching the transparent film using the sidewall pattern and the opaque film as a mask; and removing the coating on the sidewall. 7. A step of laminating an opaque film and a resist film of a predetermined thickness on the substrate, a step of forming the resist film into a predetermined resist pattern, and etching the opaque film using the resist pattern as a mask to form a light-shielding pattern. Step of removing the resist pattern, depositing a film on the entire surface, and anisotropically etching the film to leave a predetermined width of the film only on the sidewalls of the light-shielding pattern to form a sidewall pattern. 3. The mask manufacturing method according to claim 2, further comprising the step of: 8. A step of laminating a transparent film, an opaque film, and a resist film of a predetermined thickness on a substrate, a step of forming the resist film into a predetermined resist pattern, a step of etching the opaque film using the resist pattern as a mask, a step of etching the transparent film exposed in the removed portion of the opaque film; and a step of removing the outline of the opaque film so that the transparent film is exposed to a predetermined width along the outline of the opaque film. 3. The mask manufacturing method according to claim 2, further comprising: 9. Laminating an opaque film and a resist film on the substrate;
a step of forming the resist film into a predetermined resist pattern; a step of etching the opaque film using the resist pattern as a mask; a step of etching the substrate exposed in the removed portion of the opaque film to a predetermined depth; 3. The method of manufacturing a mask according to claim 2, further comprising the step of removing the contour of the opaque film so that an unetched portion of the substrate is exposed over a predetermined width along the contour of the opaque film.