JP2011221227A - Photomask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly accurate photomask which is capable of forming minute three-dimensional shapes with uniform height independently of dimensions of the minute three-dimensional shapes.SOLUTION: In the photomask in which a pattern of minute three-dimensional shape regions surrounded with a light shielding region is formed, light transmittance of the minute three-dimensional shape regions of which the dimensions of the three-dimensional shape regions D are twice or less than twice a boundary dimension R given by R=λ/NA, where NA is an aperture ratio of a projection lens for projecting the pattern of the photomask onto a substrate to be exposed and λ is a wavelength of exposure light, is made lower than light transmittance of the minute three-dimensional shape regions of which the dimensions D are equal to or larger than three times the boundary dimension R.

Description

  The present invention relates to a photomask used for manufacturing a micro three-dimensional array formed on a liquid crystal panel, a micro three-dimensional array formed on a semiconductor substrate, or a micro three-dimensional array such as a MEMS or a biochip. Is.

  When manufacturing a micro three-dimensional array such as spacers formed on a liquid crystal panel, a micro lens micro three-dimensional array for each light receiving element of a semiconductor of an imaging device, or a micro three-dimensional array such as a MEMS or a biochip In addition, when a micro three-dimensional mold array is formed on the mold or mother mold forming the array, the micro three-dimensional shape is transferred to the photosensitive resist material layer using a photomask. ing.

  Patent Document 1 discloses a technique in which a photosensitive resist material layer is formed on a substrate to be exposed, a photomask pattern is projected and exposed on the photosensitive resist material layer, and developed to obtain a micro three-dimensional shape of a microlens. It is disclosed. In this method, fine figures (fine halftone dots) are placed on a photomask reticle at fine pitch intervals, and the dimensions and fine pitch of the fine figures (fine halftone figures) on the photomask are patterned with a stepper. The photosensitive resist material layer of the substrate to be exposed is exposed by distributing the exposure density by projecting to a length that is less than the wavelength of light and projecting to a length that is not resolved. Thereby, the micro three-dimensional shape of a micro lens can be formed.

Japanese Translation of National Publication No. 08-504515

  On the other hand, for example, when forming a micro three-dimensional shape of a spacer on a liquid crystal panel, it is necessary to mix micro three-dimensional shapes having different dimensions on the panel and to align their heights. As a result of diligent research, the inventors of the present invention formed a micro three-dimensional shape pattern having the same light transmittance on a photomask and projected the pattern onto the photosensitive resist material layer on the substrate to be exposed. As the size of the shape becomes smaller, the amount of light (projected light intensity) projected onto the photosensitive resist material layer deviates from the design value. As a result, the minute amount obtained by exposing and developing the photosensitive resist material layer. It was found that there is a problem that the height of the solid shape changes depending on the size of the small solid shape.

  For this reason, the present invention projects a photomask pattern onto a photosensitive resist material layer on an exposed substrate with a projection lens to form a micro three-dimensional shape. It is an object of the present invention to obtain a photomask capable of forming a micro three-dimensional shape with the same height without depending on the size of the micro three-dimensional shape.

  In order to solve the above-described problems, the present invention provides a photomask in which a pattern of a micro three-dimensional area surrounded by a light shielding area is formed, and the dimension D of the micro three-dimensional area covers the pattern of the photo mask. With respect to the boundary dimension R = λ / NA with respect to the aperture ratio NA of the projection lens projected onto the exposure substrate and the wavelength λ of the exposure light, the light transmittance of the micro three-dimensional shape region in which the dimension D is not more than twice the boundary dimension R The photomask is characterized in that the dimension D is smaller than the light transmittance of a micro three-dimensional region that is three times or more the boundary dimension R.

Further, the present invention is the above-described photomask, wherein the dimension D is less than twice the boundary dimension R and the light transmittance of the micro three-dimensional region, and the dimension D is more than three times the boundary dimension R. The photomask is characterized in that it is reduced to [0.0450 (D / R) ² −0.328 (D / R) +1.5666] to the light transmittance of the minute three-dimensional shape region. .

  Further, the present invention is the above-described photomask, wherein at least the micro three-dimensional region in which the dimension D is equal to or less than twice the boundary dimension R is set at a lattice point having a pitch smaller than the boundary dimension R. A photomask having a pattern of light-shielding fine halftone dots and a fine gap figure between the fine halftone dots.

  In addition, the present invention is the above-described photomask, wherein at least one of the micro three-dimensional regions has a semi-transparent film formed on a transparent substrate.

In the photomask of the present invention, the dimension D is not more than twice the boundary dimension R with respect to the boundary dimension R = λ / NA with respect to the aperture ratio NA of the projection lens that projects the photomask pattern onto the substrate to be exposed and the wavelength λ of the exposure light. The light transmittance of the mask of the pattern of the micro three-dimensional region is [0.0450 (D / R) with respect to the light transmittance of the mask of the pattern of the micro three-dimensional shape region whose dimension D is three times the boundary dimension R or more. ^{2 -0.328 (D / R) +1.566} ] fraction of it to 1, 2 times the micro three-dimensional shaped region dimensions D boundary dimension R also, the dimension D is more than 3 times the boundary dimension R There is an effect that the photosensitive resist material layer on the exposed substrate can be exposed with the same projection light intensity as that of the micro three-dimensional shape region.

1 is a plan view of a photomask according to a first embodiment of the present invention. It is a sectional side view of the photomask of the 1st Embodiment of this invention. (A) It is a figure which shows the simulation result of the light intensity distribution of the exposure amount (projection light intensity | strength T) by which the pattern of the micro three-dimensional shape area | regions 2a-2d of a photomask of this invention is projected on a to-be-exposed board | substrate. (B) It is a figure which shows the function F which gives the projection light intensity | strength T of the micro solid shape area | region obtained by simulation. It is a top view of the photomask of the 2nd Embodiment of this invention. It is a sectional side view of the photomask of the 2nd Embodiment of this invention. It is a top view of the photomask of the 3rd Embodiment of this invention. It is a sectional side view of the photomask of the 3rd Embodiment of this invention.

<First Embodiment>
(Photomask)
The first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a plan view of four patterns of micro three-dimensional regions 2a to 2d surrounded by a light shielding region 3 of the photomask 10 of the present embodiment. In the photomask 10 of the present embodiment, a light-shielding film is formed on the transparent substrate 1 such as synthetic quartz glass by vapor deposition of chromium (Cr) (if necessary, a two-layer film of Cr and chromium oxide). A film is formed to 200 nm, and a pattern is formed by etching Cr or the like of the light shielding film. Thereby, in the area surrounded by the light-shielding area 3, the patterns of the micro three-dimensional shape areas 2a to 2d in which a set of the micro-gap figures 4 exposing the transparent substrate 1 are formed are formed. Between the minute gap figures 4, there is a light-shielding minute halftone figure 3a formed by a Cr light-shielding film pattern. The minute gap pattern 4 is formed in a staggered pattern on a lattice point having a pitch P.

  In the photomask 10 of FIG. 1, the patterns of the micro three-dimensional regions 2a to 2d surrounded by the light-shielding region 3 and formed by a set of the micro gap patterns 4 have columnar micro three-dimensional shapes having rectangular bottom surfaces with respective dimensions. Used to form. The micro three-dimensional shape region 2a is a square pattern having a dimension Da of 2.5 μm on one side, and the pattern is projected onto the photosensitive resist material layer on the surface of the substrate 30 to be exposed by the projection lens 20 so that the same dimension is obtained. A micro three-dimensional shape is formed. The micro three-dimensional region 2b is a square pattern having a side dimension Db of 5 μm, the micro three-dimensional region 2c is a square pattern having a side dimension Dc of 7.5 μm, and the micro three-dimensional region 2d is a square having a side dimension Dd of 10 μm. Pattern.

  Then, in the square area of each dimension D of the minute solid shape areas 2a to 2d surrounded by the light-shielding area 3, the minute gap figure is staggered on a lattice point having a pitch P (P = 500 nm in FIG. 1). 4 is formed. FIG. 2 shows a cross-sectional view of the photomask 10. As shown in FIG. 2, a pattern of a light shielding region 3 made of a Cr light shielding film and a fine halftone dot pattern 3a is formed on the transparent substrate 1, and the transparent substrate 1 is exposed between the light shielding fine halftone dot pattern 3a. A pattern of the gap graphic 4 is formed. Then, by changing the area ratio between the minute dot pattern 3a and the minute gap pattern 4, the minute three-dimensional region 2 in which the light transmittance is controlled is formed.

  The pattern of the photomask 10 is projected onto the photosensitive resist material layer on the exposed substrate 30 at the same magnification by the projection lens 20 of the stepper and exposed. That is, when the exposure light L0 is irradiated onto the photomask 10, the exposure light L0 passes through the minute gap figure 4, and the pattern is exposed at the same magnification by the projection lens 20 of the reduction projection type exposure apparatus (stepper). Pattern exposure is performed by projecting onto a photosensitive resist material layer formed on the surface 30.

(Pitch P of lattice point of photomask)
As a result of diligent research, the fine gap figure 4 is formed in a staggered pattern at the lattice points of the pitch P in the fine three-dimensional shape region 2 surrounded by the light shielding region 3 of the photomask 10. Set the following dimensions. That is, the aperture ratio NA of the projection lens 20 on the exposed substrate 30 side of the stepper and the wavelength λ of the exposure light are proportional to the resolution of the pattern of the micro three-dimensional region 2 projected onto the exposed substrate 30 (defined by Equation 1). ) A pitch P smaller than the boundary dimension R = λ / NA is set (Formula 2). By setting the pitch P, a substantially uniform light distribution pattern can be projected onto the substrate 30 to be exposed. The photosensitive resist material layer on the exposed substrate 30 exposed by projecting the pattern of the micro three-dimensional region 2 of the photomask 10 is developed, so that the surface of the exposed substrate 30 has a small height unevenness. A three-dimensional shape can be formed.
(Formula 1) R = λ / NA
(Formula 2) P <R

  The pattern of the photomask 10 is exposed with exposure light L0 having a wavelength λ of 365 nm under the condition that the aperture ratio NA of the projection lens 20 on the exposure substrate 30 side of the stepper is 0.15 and the coherence factor σ is 0.6. When the boundary dimension R is calculated by (Equation 1) when the substrate 30 is exposed, the boundary dimension R is calculated as R = λ / NA = 365 nm / 0.15 = 2433 nm = 2.43 μm. The pitch P of the lattice point (grid) of the photomask 10 is set to a pitch P of 500 nm, which is larger than the exposure wavelength λ = 365 nm but smaller than the boundary dimension R = 2.43 μm.

(Photomask gradation)
In the pattern of the photomask 10, a minute gap graphic 4 having a dimension (area) changed according to a gradation (gray scale: density) designated in each part of the mask is set at a lattice point. That is, the gradation is adjusted by changing the light transmittance at each lattice point of the photomask by changing the length of the side of the rectangular minute gap figure 4 from 0 to twice the pitch P of the lattice point. . For example, the photomask 1 is formed by arranging rectangular minute gap figures 4 each having a side of 316 nm in a staggered pattern on the lattice points.
The ratio of the area of the minute gap figure 4 to the 0 light irradiation region is set to 20%.

(Dependence of projected light intensity on dimension D of the micro three-dimensional region)
FIG. 3A shows an exposure amount (projection) in which the patterns of the micro three-dimensional regions 2a to 2d surrounded by the light shielding region 3 of the photomask 10 shown in FIG. The simulation result of the light intensity distribution of the light intensity T) is shown. In this case, in the pattern of the photomask 10, the minute gap figures 4 are arranged in a staggered pattern on lattice points having a pitch P = 0.5 μm smaller than the boundary dimension R = 2.43 μm. Here, aiming at the projection light intensity T of the light projected onto the substrate 30 to be exposed by the projection lens 20 in the minute three-dimensional shape region 2 in the photomask 10 (target projection light intensity A = 0). .2), the dimension of one side of the rectangle of the minute gap figure 4 was set to 316 nm. In this case, the light shielding fine halftone dots 3a between the minute gap figures 4 are connected at the ends. The horizontal axis X in FIG. 3A represents the position coordinates of the pattern in which each micro three-dimensional region 2a to 2d is projected onto the substrate 30 to be exposed by the projection lens 20. The distribution of the projection light intensity T as a result of the simulation is as follows: the dimension in which the micro three-dimensional area 2a having the dimension Da is projected is 2.5 μm, the dimension in which the micro three-dimensional area 2b having the dimension Db is projected is 5 μm, and the micro solid having the dimension Dc. A square micro three-dimensional exposure pattern is projected onto the substrate 30 to be exposed, with the size projected onto the shape area 2c of 7.5 μm and the dimension onto which the micro solid area 2d with the dimension Dd projected is 10 μm.

  The simulation result shown in FIG. 3A shows that the light intensity distribution projected onto the substrate to be exposed 30 is small in the micro three-dimensional regions 2b to 2d in which the dimension D of the square micro three-dimensional region 2 of the photomask 10 is 5 μm or more. The peaks of the projected light intensity T are approximately 20%. On the other hand, in the micro three-dimensional shape region 2a having the dimension Da of 2.5 μm, the projection light intensity T projected onto the substrate 30 to be exposed is 25%, and the projection light intensity T is higher than the patterns of the other micro three-dimensional shape regions 2. Increases by about 25%. As described above, when the dimension D of the micro three-dimensional region 2 surrounded by the light shielding region 3 in the photomask 10 becomes smaller than the boundary dimension R = 2.43 μm calculated by (Equation 1), the projection lens 20 causes the substrate to be exposed. It was found that the projection light intensity T projected onto the lens 30 starts to increase.

As a result of the simulation, when the dimension D of the minute solid shape region 2 becomes smaller, the projection light intensity T of the minute solid shape region 2 becomes larger. As a relational expression thereof, the ratio of the dimension D of the minute solid shape region 2 to the boundary dimension R (D / R) is multiplied by a coefficient A and a function F represented by a polynomial is obtained to obtain the following (Expression 3) representing the projected light intensity T.
(Formula 3) T = A · F
= A · [0.0450 (D / R) ² −0.328 (D / R) +1.666]
(Formula 4) (D / R) <4
The applicable range of (Equation 3) is effective for the dimension D within the range of (D / R) <4 (Equation 4). The coefficient A in (Expression 3) represents the light intensity (projection light intensity T) at which the micro three-dimensional region 2 having the dimension D three times or more the boundary dimension R is exposed and projected onto the exposure target substrate 30 by the projection lens 20. .

The calculation result of the projection light intensity T, that is, the function F in the case of A = 1 in (Equation 3) is shown by a solid line in FIG. Thus, by (Equation 3), the projection light intensity T projected onto the exposed substrate 30 as a function of the dimension D of the micro three-dimensional region 2 can be calculated. Thus, the projection light intensity T has a relationship that increases as the dimension D of the minute three-dimensional shape region 2 decreases. By using the relational expression (Equation 3) in which the projection light intensity T obtained in this way depends on the dimension D of the minute three-dimensional shape region 2, the target light intensity can be kept constant regardless of the dimension D of the minute three-dimensional shape region 2. The light transmittance of the micro three-dimensional region 2 of the photomask that exposes the exposure substrate 30 can be calculated. That is, in the photomask 10, for a small three-dimensional shape region 2 whose dimension D is twice or less than the boundary dimension R, the dimension is adjusted so that the light transmittance A 1 is set to the following (formula 5). By forming the gap figure 4, the dependency of the projection light intensity T projected onto the substrate 30 to be exposed by the projection lens 20 is corrected.
(Expression 5) Light transmittance of mask A1 = A0 / F
= A0 / [0.0450 (D / R) ² −0.328 (D / R) +1.566] That is, in the photomask 10, the pattern of the micro three-dimensional region whose dimension D is not more than twice the boundary dimension R The light transmittance A1 of [0.0450 (D / R) ² −0.328 (D / R) with respect to the light transmittance A0 of the pattern of the micro three-dimensional region whose dimension D is three times or more of the boundary dimension R. ) +1.566]. As a result, the projection light intensity T projected onto the substrate to be exposed 30 by the projection lens 20 is such that the dimension D is 3 times or more the boundary dimension R even in the micro three-dimensional shape region 2 whose dimension D is 2 times or less the boundary dimension R. There is an effect that the same projection light intensity T as that of the minute solid shape region 2 can be made uniform.

<Second Embodiment>
FIG. 4 shows a plan view of the photomask 10 of the second embodiment, and FIG. 5 shows a side sectional view thereof. In the second embodiment, as shown in the side sectional view of FIG. 5, the layer of the semi-transparent film 5 is formed on the transparent substrate 1 of the photomask 10. Then, a light-shielding film layer is formed on the semi-transparent film 5 layer, and the light-shielding region 3 and the minute dot pattern 3a are formed with the pattern of the light-shielding film layer. The light transmittance of the layer of the semi-transparent film 5 is set equal to the value of the projected light intensity T (light transmittance A0) in the micro three-dimensional regions 2c and 2d whose dimension D is three times or more the boundary dimension R. Then, as shown in FIG. 4, a light-shielding fine halftone dot pattern 3a is formed in the fine three-dimensional shape regions 2a and 2b whose dimension D is not more than twice the boundary dimension R. A pattern of the minute gap figure 4a is formed between the minute dot figure 3a. In the second embodiment, contrary to the first embodiment, a pattern is formed in which the fine halftone dots 3a between the light-shielding fine halftone dots 3a are connected at the ends. This light-shielding minute halftone dot pattern 3a is arranged in a staggered pattern on lattice points having a pitch P smaller than the boundary dimension R = λ / NA (defined by Equation 1). On the other hand, in the minute solid shape regions 2c and 2d whose dimension D is three times or more of the boundary dimension R, the entire area of each of the minute solid shape regions 2c and 2d is not formed in the light shielding region 3 without forming the minute dot pattern 3a. Is formed in the opening 6 having a length D on one side surrounded by. In the micro three-dimensional regions 2c and 2d, the entire surface of the transparent substrate 1 is covered with the semi-transparent film 5, so that the light transmittance of the opening 6 is set to the light transmittance A0.

In the micro three-dimensional regions 2a and 2b in which the dimension D of the photomask 10 is less than or equal to twice the boundary dimension R, the light transmittance A1 is adjusted as shown in (Formula 5) by adjusting the dimension of the micro dot pattern 3a. , to ^{[0.0450 (D / R) 2} -0.328 (D / R) +1.566] 1 of worth to light transmittance A0 of micro three-dimensional shaped region 2c and 2d. As a result, the dependency of the projection light intensity T on the dimension D is corrected, and the projection light intensity T projected onto the substrate to be exposed 30 is a micro solid whose dimension D is not more than twice the boundary dimension R, as in the first embodiment. The shape area 2 also has an effect that the same projection light intensity T as that of the micro three-dimensional shape area 2 whose dimension D is three times or more the boundary dimension R can be obtained.

  The semi-transparent film 5 used in the present embodiment is made of the following material and formed into the following thickness so that the light transmittance is 20%. When i-line (wavelength λ = 365 nm) of a mercury lamp is used as exposure light, a thin film having a composition of molybdenum oxide silicide (MoSiO) and 40% atomic percent of oxygen (O) is 80 to 120 nm in thickness. If the light-transmitting film 5 is formed, the light transmittance is about 20% at the wavelength of i-line. Further, a semi-transparent film 5 having a thickness of 64 nm is formed from a thin film of molybdenum oxynitride silicide (MoSiON) having a component composition of 40% atomic% of oxygen (O) and 18% atomic% of nitrogen (N). Then, the light transmittance is about 20% at the wavelength of i-line. Further, in the case of exposure at a wavelength λ (= 248 nm) of a KrF excimer laser, molybdenum nitride silicide (MoSiN) has a composition in which nitrogen (N) is 48 atomic%, Si is 34 atomic%, and Mo is 18 atomic%. If the semi-transparent film 5 is formed with a thickness of 35 nm, the light transmittance of the semi-transparent film 5 at that wavelength is about 20%.

As a method for manufacturing the semi-transparent film 5, for example, a thin translucent film 5 of molybdenum oxynitride silicide (MoSiON) can be formed on the transparent substrate 1 made of a synthetic quartz glass substrate by reactive sputtering. That is, the semi-transparent film 5 uses a mixed target (Mo: Si = 1: 2 mol%) of molybdenum (Mo) and silicon (Si), and uses argon (Ar), nitrous oxide (N ₂ O), and Can be formed by performing reactive sputtering in a mixed gas atmosphere (Ar; 84% by volume, N ₂ O; 16% by volume, pressure: 1.5 × 10 ⁻³ Torr).

<Third Embodiment>
FIG. 6 shows a plan view of the photomask 10 of the third embodiment, and FIG. 7 shows a side sectional view thereof. In the third embodiment, as in the second embodiment, the semi-transparent film 5 is formed between the light shielding film layer and the transparent substrate 1. As in the plan view of FIG. 6, in the small three-dimensional shape regions 2c and 2d whose dimension D is three times or more of the boundary dimension R, the minute dot pattern 3a is not formed as in the second embodiment. The entire three-dimensional region 2 is formed as an opening 6 having a side length D surrounded by the light-shielding region 3, and the entire surface of the transparent substrate 1 in the opening 6 is covered with the semi-transparent film 5, so that the light transmittance of the region can be increased. The light transmittance A0 of the semi-transparent film 5 is set.

  In the third embodiment, the micro three-dimensional shape region 2b is different from the second embodiment. That is, in the minute three-dimensional shape region 2b, as shown in the side sectional view of FIG. 7, the semi-transparent film 5 is removed in the minute gap pattern 4b between the light-shielding minute dot patterns 3a, and the surface of the transparent substrate 1 is removed. To expose. On the other hand, in the minute solid shape region 2a, the semi-transparent film 5 is left in the minute gap pattern 4a between the light-shielding minute dot patterns 3a.

The pattern of the semi-transparent film 5 of the photomask 10 is formed as follows. That is, the semi-transparent film 5 having the light transmittance A0 of the micro three-dimensional region 2a is covered with an etching resist material layer, and the semi-transparent film 5 of the micro three-dimensional region 2b is a pattern of the light-shielding region 3 and the micro dot pattern 3a. Is used as an etching mask and dry etching is performed using an etching gas of a CF ₄ + O ₂ mixed gas, so that in the minute solid shape region 2b, a minute gap graphic which is a portion other than the base of the light shielding region 3 and the minute dot graphic 3a The semitranslucent film 5b of 4b is removed by dry etching to expose the surface of the transparent substrate 1.

  In the third embodiment, the transparent substrate 1 has a portion where the surface of the transparent substrate 1 is covered with the semi-transparent film 5 and a portion where the surface of the transparent substrate 1 is exposed by removing the semi-transparent film 5. Thus, in order to obtain the light transmittance A1 of the mask required by the micro three-dimensional shape region 2b calculated by Equation 5, instead of using the micro dot pattern 3a having a small pattern that is difficult to manufacture, the transparent substrate 1 By using the minute gap graphic 4b with the exposed surface, the minute dot graphic 3a can be formed in an appropriate size. Accordingly, there is an effect that the manufacturing cost of the photomask 10 can be reduced by easily forming the micro three-dimensional region 2b having the light transmittance A1 of the mask necessary for obtaining the required projection light intensity T.

Note that the present invention is not limited to the photomask 10 in which the light-shielding minute halftone dots 3a and the minute gaps 4 are square, but they may be rectangular or other polygonal shapes. Further, the positions of the grid points where the minute dot graphics 3a and the minute gap graphics 4 are installed are not limited to the staggered positions, and the minute dot graphics 3a may be installed over all the lattice points. A photomask 10 in which the pitch P of dots is changed depending on the portion of the photomask 10 may be used. Furthermore, the present invention changes the thickness of the semi-transparent film 5 exposed to the opening 6 without using the fine halftone dot pattern 3a and the minute gap graphic 4 in accordance with the dimension of the minute three-dimensional shape region 2. The light transmittance A1 of the mask of the pattern of the micro three-dimensional shape region 2 where D is not more than twice the boundary dimension R = λ / NA, and the mask of the pattern of the micro three-dimensional shape region 2 where the dimension D is three times or more of the boundary dimension R Alternatively, the photomask 10 may be reduced to [0.0450 (D / R) ² −0.328 (D / R) +1.566] of the light transmittance A0.

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2, 2a, 2b, 2c, 2d ... Micro solid shape area 3 ... Light-shielding area 3a ... Micro dot figure 4, 4a, 4b ... Micro gap figure 5 ... Semitranslucent film 6... Opening 10... Photomask 20... Projection lens 30 .. Exposed substrate D, Da, Db, Dc, Dd. ..Exposure light P: Pitch of lattice points where fine dot patterns (fine gap figures) are placed

Claims (4)

  A photomask in which a pattern of a micro three-dimensional shape region surrounded by a light-shielding region is formed, and the dimension D of the micro three-dimensional shape region is an aperture ratio NA of a projection lens that projects the photo mask pattern onto an exposed substrate. Regarding the boundary dimension R = λ / NA with respect to the wavelength λ of the exposure light, the dimension D is the light transmittance of the minute three-dimensional shape region that is not more than twice the boundary dimension R, and the dimension D is three times the boundary dimension R. A photomask characterized in that it is smaller than the light transmittance of the micro three-dimensional region. 2. The photomask according to claim 1, wherein the dimension D is a light transmittance of the micro three-dimensional shape region that is not more than twice the boundary dimension R, and the dimension D is not less than three times the boundary dimension R. A photomask characterized by being reduced to [0.0450 (D / R) ² −0.328 (D / R) +1.566] / one of the light transmittance of a three-dimensional region.   3. The photomask according to claim 1, wherein at least the micro three-dimensional shape region in which the dimension D is equal to or less than twice the boundary dimension R is installed at a lattice point having a pitch smaller than the boundary dimension R. 4. A photomask having a pattern of light-shielding fine halftone dots and a fine gap figure between the fine halftone dots.   4. The photomask according to claim 1, wherein at least one of the micro three-dimensional regions has a semi-transparent film formed on a transparent substrate. 5.

Images