JPH09148214A - Method of coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the deviation of pattern dimensions due to variations in thickness of a coating when patterns are formed by spin coating on a substrate having a step. SOLUTION: When a substrate having a step of less than 100 microns in width is coated by spin coating, the coating is set to a thickness corresponding to a point shifted +0.01 to +0.10 in terms of the period from a peak of a standing-wave curve Sw that represents pattern dimensions varying with variations in thickness of the coating, so as to reduce the deviation of pattern dimensions. In the case of a substrate having a step of greater than 100 microns, on the other hand, the coating is set to a thickness corresponding to a point shifted +0.10 to +0.30 in terms of the period from a peak of the standing-wave curve Sw, so as to reduce the area in which pattern formation is inhibited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a coating film such as a resist film or an SOG (Spin on glass) film used in a semiconductor device.

[0002]

2. Description of the Related Art In recent years, as LSIs have been highly integrated, a highly accurate pattern forming technique has been required. The accuracy is generally within ± 10% of the design rule. For example, VLSI with a design rule of 0.35 μm
Then, the uniformity of the pattern dimension of ± 0.035 μm is required.

The following items can be cited as causes of the deterioration of the accuracy. (1) Variation of resist film thickness, (2) Standing wave effect, (3) Variation of resist dissolution rate, (4) Variation of various resist material properties, (5) Exposure equipment optical and mechanical Fluctuation, (6) reticle pattern size variation, (7) etching variation, (8) substrate light reflectance variation (or film thickness variation of coating film formed on substrate surface), (9) substrate Step due to pattern, influence of acid / alkali in (10) atmosphere (especially in case of chemically amplified resist). Among the above, (1) to (4) and (10) are factors of variation of the pattern dimension in the photolithography process. The problem to be solved by the present invention relates to (1) and (2), and is the fluctuation of the pattern dimension due to the local fluctuation of the resist film thickness caused by the step.

Considering the above-mentioned factors of variation in the pattern size, in a VLSI having a design rule of 0.35 μm, for example, a so-called bare wafer is required to have a film thickness uniformity of 5 nm or less.

Here, the relationship between the dimensions of the resist pattern and the resist film thickness will be described. When the resist film thickness changes, the dimensions of the resist pattern after development also change. This relationship is shown in FIG. In FIG. 5, the vertical axis represents the dimension (line width) of the resist pattern, and the horizontal axis represents the resist film thickness.

As shown in FIG. 5, in general, the size of the resist pattern is determined by the interference between the exposure light and the reflected light from the underlayer, and a certain amplitude and period [2λ / n (λ: exposure wavelength,
n: refractive index of resist)]. The state is shown by the curve a. This is called the standing wave effect. Since this amplitude becomes larger as the reflected light from the underlayer becomes stronger, the controllability of the dimensions of the resist pattern becomes worse. Therefore, it is necessary to prevent reflection on a base having a high reflectance such as an aluminum film. Examples of the material of the antireflection film include amorphous silicon (a-Si), titanium oxynitride (TiON), and organic high absorption materials. The standing wave effect is reduced by reversing the phase and causing the light to interfere in the direction of canceling the standing wave by using the film as described above.

Then, the dimension change of the resist pattern when the antireflection is completely applied becomes almost linear as shown by the straight line b, and the phenomenon that the dimension of the resist pattern becomes thicker as the resist film thickness becomes larger remains. . This is called the bulk effect.

The required uniformity of the film thickness can be realized when the film is formed on a flat substrate surface. However, a step is usually formed on an actual substrate, and the step causes a film thickness variation more than an allowable value. In general, the resist film thickness is a region where the film thickness variation due to standing waves is small, that is, the standing wave peak (point p in FIG. 5).
Is fitted to the part of. That is, the position near the point p has the largest allowable range for the film thickness variation. However, in the vicinity of the step, there is a large local variation in the resist film thickness, so it was unclear at which point in the standing wave the film thickness came.

Therefore, there is a demand for a method of forming a coating film which can reduce the area where the coating film thickness varies in the step portion to reduce the dimensional variation due to the bulk effect.

[0010]

However, the film thickness uniformity required for the resist film must be at least 5 nm or less when the film is formed on a so-called bare wafer. Normally, even if it is possible to achieve it when a film is formed on a flat substrate surface, since a step is formed on an actual substrate, the step causes a film thickness variation more than an allowable value. Along with this, the area in which the dimensions of the pattern formed on the step varies also becomes large.

An object of the present invention is to provide a method for forming a coating film in which the dimensional variation of the pattern formed by the coating film is small.

[0012]

The present invention is a method for forming a coating film, which has been made to achieve the above object. That is, the first method is a method of forming a coating film by spin coating to form a film by applying a coating solution to a substrate surface having a step on the substrate surface and the width of the step being 100 μm or less. The film thickness of the coating film is +0.01 or more of the period of the standing wave curve from the maximum value of the standing wave curve that represents the pattern dimension that periodically changes according to the change of the film thickness of the coating film.
This is a method in which coating is performed by setting the film thickness value at a shifted position within a range of 0.10 or less.

In the first method, the film thickness of the coating film is set to a film thickness value at a position deviated from the maximum value of the period of the standing wave curve in the range of +0.01 or more and +0.10 or less of the period. Therefore, the film thickness variation of the coating film caused by the step is taken into consideration. That is, the film thickness of the coating film on the top and bottom of the step is taken into consideration. Therefore, the size (line width) variation of the pattern formed by the coating film in the step portion is reduced.

The second method is a coating film formed by spin coating to apply a coating solution to a substrate surface having a step on the substrate surface and the width of the step being 100 μm or more and less than the radius of the substrate. The method for forming a coating film according to claim 1, wherein the film thickness of the coating film changes from the maximum value of the standing wave curve representing the pattern dimension that periodically changes according to the change of the film thickness of the coating film to +0 of the period of the standing wave curve. It is a method in which coating is performed by setting the film thickness value at the shifted position in the range of 10 or more and +0.30 or less.

In the second method, the film thickness of the coating film is set to a film thickness value at a position deviated from the maximum value of the period of the standing wave curve within the range of +0.10 to +0.30 of the period. Therefore, the film thickness variation of the coating film caused by the step is taken into consideration. That is, the film thickness of the coating film on the top and bottom of the step is taken into consideration. Therefore, the range in which the dimension (line width) variation of the pattern formed by the coating film in the step portion increases becomes small.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An example of a first embodiment according to the present invention will be described with reference to FIG. In the figure, the left vertical axis shows the pattern dimension variation (line width variation), the right vertical axis shows the pattern dimension (line width), and the horizontal axis shows the coating film normalized by the period of the standing wave effect. Film thickness (λ / 2n) [λ: exposure wavelength, n: refractive index of coating film]. Therefore,
The positions of 6.00 and 7.00 show the maximum values of the pattern size distribution generated by the standing wave effect, and 6.50 and 7.50.
The position of indicates the minimum value of the pattern size distribution generated by the standing wave effect.

As shown in FIG. 1, the film thickness of the coating film is a maximum value (of a standing wave curve Sw (indicated by a broken line) of a standing wave curve Sw (indicated by a broken line) that represents a pattern dimension that periodically changes in accordance with a change in the film thickness of the coating film. For example, the film thickness value at a position shifted from 7.00) in the range of +0.01 or more and +0.10 or less of the period of the standing wave curve Sw, that is, the range D1 of 7.01 to 7.10 is set. .

As can be seen from the dimension variation distribution curve Lw shown in FIG. 1, the pattern dimension variation is 0.0 when the coating film thickness is 6.60.
The minimum value is 21 μm, and when the thickness of the coating film is 7.05, the dimensional variation of the pattern is a minimum value of 0.015 μm. Among them, the minimum value when the film thickness of the coating film is 6.60 is 7.00 when the film thickness of the coating film which is conventionally set is 7.00.
The variation in the dimension of the pattern at the time of (the maximum value of the dimension distribution of the pattern caused by the standing wave effect) becomes a value larger than 0.020 μm. On the other hand, from the maximum value of the standing wave curve (for example, 7.00), the dimensional variation of the pattern tends to decrease in the direction in which the film thickness increases.
When the film thickness of the coating film is 7.05, the dimensional variation of the pattern changes in the direction of increasing. Then, the dimensional variation of the pattern when the film thickness of the coating film is 7.10 and the film thickness of the coating film is 7.00 is almost equal. Therefore, the film thickness of the coating film is set within the above-mentioned range so that the dimensional variation of the pattern is at least equal to or smaller than the conventional setting value of the film thickness.

By setting the film thickness of the coating film under the above conditions, the dimensional variation of the pattern obtained by exposing and developing the coating film is set to the film thickness at which the standing wave curve Sw has the maximum value. It is smaller than the dimensional variation of the pattern using the coating film applied in this way.

The relationship between the dimensional variation of the pattern shown in FIG. 1 and the film thickness of the coating film can be obtained by the simulation described below.

Next, the simulation method will be described below. Here, as shown in FIG. 2, a step 52 (for example, width =
A case will be described in which the coating film 61 is formed on the surface of the wafer 51 having a w, height = δ concave portion). Further, from the center direction of the wafer 51 toward the outer peripheral direction, the upper part of the step is Sui, the bottom part of the step is Sb, and the upper part of the step is Suo.

First, a coating film 61 is formed on the surface of the wafer 51 rotating at a set angular velocity by the spin coating method. The film thickness of the coating film 61 is expressed by the equation (1).

[0023]

H = aexp (-λx) + bexp (λx / 2) cos (√3λx / 2) + cexp (λx / 2) sin (√3λx / 2) (1) [wherein (1) ^{λ = (3Ω 2) 1/3 =} {3 (ρω 2 w 3
_{r 0) / (γhf)}} 1/3, x = ( represents the _{r-r 0) / w,} ρ: density of the coating liquid, omega: wafer of the angular velocity, w: a wafer step width, r: a wafer center , R ₀ : distance between wafer center and step center, γ: surface tension of coating liquid, h
f: represents the coating film thickness at a flat position on the wafer away from the step]

From the equation (1) above, the step upper part Sui
The film thickness H ₁ of the upper coating film 61 is expressed by the equation (2).

[0025]

H ₁ = b ₁ exp (λx / 2) cos (√3λx / 2) + c ₁ exp (λx / 2) sin (√3λx / 2) +1 (2)

Further, the film thickness H ₂ of the coating film 61 on the step bottom portion Sb is expressed by the equation (3).

[0027]

H ₂ = a ₂ exp (−λx) + b ₂ exp (λx / 2) cos (√3λx / 2) + c ₂ exp (λx / 2) sin (√3λx / 2) +1 (3) )

Further, the film thickness H ₃ of the coating film 61 on the step upper portion Suo is expressed by the equation (4).

[0029]

## EQU00004 ## H ₃ = a ₃ exp (-λx) +1 (4)

Here, ex in the above equations (2) to (4)
p (-λx), exp (λx / 2) cos (√3λx /
2) and exp (λx / 2) sin (√3λx / 2) are represented by ψ ₁ , ψ ₂ , ψ as shown in formulas (5) to (7).
Replace with ₃ .

[0031]

[Number 5] _{exp (-λx) = ψ 1 ···} (5)

[0032]

(6) exp (λx / 2) cos (√3λx / 2) = ψ ₂ (6)

[0033]

(7) exp (λx / 2) sin (√3λx / 2) = ψ ₃ (7)

Therefore, the above equations (2) to (4) are
Expressions (8) to (10) are expressed.

[0035]

[Equation 8] H ₁ = b ₁ ψ ₂ + c ₁ ψ ₃ +1 (8)

[0036]

H ₂ = a ₂ ψ ₁ + b ₂ ψ ₂ + c ₂ ψ ₃ +1 (9)

[0037]

[Equation 10] H ₃ = a ₃ ψ ₁ +1 (10)

Then, the continuous condition at the step 52 is
Equations (8) to (10), equations (8) to (10) that have been differentiated once, and equations (8) to (10) that have been differentiated twice are defined as continuous conditions at the step 52. Obtained by solving as a simultaneous equation. That is, equations (8) to (1
The expression obtained by differentiating the expression (0) once is expressed as the expressions (11) to (13).

[0039]

H ₁ '(x) = b ₁ ψ' ₂ + c ₁ ψ ' ₃ (11)

[0040]

H ₂ '= a ₂ ψ ₁ ' + b ₂ ψ ₂ '+ c ₂ ψ ₃ ' (12)

[0041]

[Equation 13] H ₃ '= a ₃ ψ ₁ ' (13)

The expressions obtained by differentiating the expressions (8) to (10) twice are expressed as the expressions (14) to (16).

[0043]

[Equation 14] H ₁ "(x) = b ₁ ψ" ₂ + c ₁ ψ " ₃ (14)

[0044]

[Equation 15] H ₂ "= a ₂ ψ ₁ " + b ₂ ψ ₂ "+ c ₂ ψ ₃ " (15)

[0045]

[Equation 16] H ₃ '= a ₃ ψ ₁ "... (16)

Therefore, the step top Sui and the step bottom Sb
Considering the step, the continuous condition at the step with
Expressions (7) to (19) are obtained. Also, s = δ
/ Hf, which represents a step difference standardized by the thickness of the resist film.

[0047]

B ₁ ψ ₂ + c ₁ ψ ₃ + s = a ₂ ψ ₁ + b ₂ ψ ₂ + c ₂ ψ ₃ (17)

[0048]

B ₁ ψ ′ ₂ + c ₁ ψ ′ ₃ = a ₂ ψ ₁ ′ + b ₂ ψ ₂ ′ + c ₂ ψ ₃ ′ (18)

[0049]

## EQU19 ## b ₁ ψ " ₂ + c ₁ ψ" ₃ = a ₂ ψ ₁ "+ b ₂ ψ ₂ " + c ₂ ψ ₃ "(19)

Further, the continuous condition for the step difference between the step bottom Sb and the step upper part Suo is as follows in consideration of the step (20).
Expressions to (22) are obtained.

[0051]

## EQU20 ## a ₂ ψ ₁ + b ₂ ψ ₂ + c ₂ ψ ₃ = a ₃ ψ ₁ + s (20)

[0052]

[Expression 21] a ₂ ψ ₁ ′ + b ₂ ψ ₂ ′ + c ₂ ψ ₃ ′ = a ₃ ψ ₁ ′ (21)

[0053]

[Equation 22] a ₂ ψ ₁ "+ b ₂ ψ ₂ " + c ₂ ψ ₃ "= a ₃ ψ ₁ " (22)

For example, the above equations (17) to (22) are set to 6
When the continuous condition at x = ± _1/2 is calculated as the simultaneous equations, a ₂ , a ₃ , b ₂ , b ₁ , c ₁ , c ₂ are given by the following equations (23) to (28). become.

[0055]

A ₂ = s / 3exp (λ / 2) (23)

[0056]

A ₃ = s / 3exp (λ / 2) −s / 3exp (−λ / 2) (24)

[0057]

B ₂ = 2s · cos (√3λ / 4) / 3exp (λ / 4) (25)

[0058]

B ₁ = 2s [cos (√3λ / 4) / 3exp (λ / 4) -cos (-√3λ / 4) / 3exp (-λ / 4)] (26)

[0059]

C ₁ = 2s [sin (√3λ / 4) / 3exp (λ / 4) -sin (-√3λ / 4) / 3exp (-λ / 4)] (27)

[0060]

C ₂ = 2s · sin (√3λ / 4) / 3exp (λ / 4) (28)

As a result, the above a ₂ , a ₃ , b ₂ , b ₁ ,
Substituting c ₁ and c ₂ into the equations (2) to (4), H ₁ representing the film thickness distribution of each coating film 61 on the step upper part on Sui, the step lower part on Sb, and the step upper part on Suo. , H ₂ and H ₃ are obtained.

Then, the pattern dimension y which varies depending on the film thickness distribution of the coating film 61 and the standing wave effect is obtained by the equation (29).

[0063]

[Mathematical formula-see original document] y = (aχ + b) sin (4nπχ / λ _c + c) + dχ + e (29) [wherein (29), χ: coating thickness, n: refractive index of coating film,
λ _c : exposure wavelength, a, b, _C , d, e: standing wave regression constant]

That is, the film thickness at a predetermined position of the coating film thickness distribution represented by the above H ₁ , H ₂ , and H ₃ is defined by the above (29).
By substituting for χ in the equation, the pattern dimension y at the predetermined position, for example, the line width of the line pattern is obtained.

Next, the dimensional variation is obtained from the value of the pattern dimension y obtained above. The dimensional variation is
For example, it is simply _calculated as the difference between the maximum value y _max of the pattern dimension y and the minimum value y _min of the pattern dimension y. Usually, when the standard dimension value is y _s , y _max ≧ y _s ≧ y _min . Alternatively, it may be a difference from the average value of the pattern dimensions of a plurality of calculation points, and the variation of the pattern dimensions may be defined by other criteria.

As a result of the above simulation, the line width distribution of the pattern in the step portion can be obtained. The result is shown in FIG. In the figure, the vertical axis indicates the pattern size (line width), and the horizontal axis indicates the step position x. Further, the discontinuity of the pattern size at the step portion is caused by the step upper portions Sui and Suo and the step lower portion S.
This is because the resist film thickness changes discontinuously at the boundary with b, that is, at the position of x = ± 1/2.

As shown in FIG. 3, it can be seen that the pattern size (line width) distribution changes near the step position x = 1/2 position.

Then, using the above simulation method,
The relationship shown in FIG. 1 is obtained by obtaining the dimensional variation of the pattern for each film thickness of the coating film.

Next, the thickness of the resist film was set in consideration of the period of the standing wave effect having the effect of the step obtained in the first embodiment, and the dimensional variation of the pattern was experimentally obtained. In this experiment, a resist film was formed as a coating film by a spin coating method on the surface of the substrate on which a step having a width of 50 μm was formed in the radial direction of the substrate. As the resist, for example, a novolac-based resist was used.
Then, the resist film to be applied is applied so as to have a film thickness at a position where the period is shifted by 0.050 in the + direction from the maximum value of the standing wave curve Sw, that is, conventionally, the film thickness is 770 nm. The coating was applied so that the film thickness would be 780 nm.

As a result, the dimensional variation of the pattern in the lower portion Sb of the step was 0.015 μm. On the other hand, when the thickness of the resist film is set to the maximum value of the standing wave curve as in the conventional case, the dimensional variation of the pattern in the lower part Sb of the step is 0.020 μm. Therefore, also from the experimental results, it can be said that a pattern with small dimensional variation can be formed by setting the range of the thickness of the coating film as in the first embodiment.

Next, an example of the second embodiment according to the present invention will be described with reference to the explanatory view of the embodiment shown in FIG. In the figure, the vertical axis on the left has a pattern dimension variation of 0.005 μm.
Area, that is, the size of the pattern formation prohibited area, the right vertical axis shows the pattern dimension (line width), and the vertical axis shows the thickness of the coating film standardized by the standing wave effect period. (Λ / 2n) [λ: exposure wavelength (for example, λ = 365n
m) and n: the refractive index of the coating film (for example, n = 1.62)]. Therefore, the positions of 6.00 and 7.00 show the maximum values of the pattern size distribution generated by the standing wave effect,
The positions of 6.50 and 7.50 indicate the minimum values of the pattern size distribution generated by the standing wave effect.

As shown in FIG. 4, the film thickness of the coating film is a maximum value of the standing wave curve Sw (indicated by a broken line) (indicated by a broken line) which represents a pattern dimension which changes periodically according to the change of the film thickness of the coating film. For example, the film thickness value at a position deviated from 7.00) in the range of +0.10 to +0.30 of the period of the standing wave curve Sw, that is, set to the range D2 of 7.10 to 7.30. There is.

The size distribution curve Pw of the prohibited area shown in FIG.
As can be seen from the above, the pattern formation prohibited area has a minimum value of 15 μm when the coating film thickness is around 6.78 and the coating film thickness is around 7.14. In addition, the pattern formation prohibited region has a minimum value of 10 μm. Then, the maximum value of the standing wave curve (for example, 7.0
From 0), the size of the prohibited area for pattern formation tends to decrease in the direction of increasing the film thickness, and the prohibited area for pattern formation is Change to increase. Here, the film thickness of the coating film is set in the above range, which has a large effect of reducing the pattern formation prohibited region. Therefore, the film thickness of the coating film is
It is set within the above-mentioned range so that the dimensional variation of the pattern is at least equal to or smaller than the conventional setting value of the film thickness.

By setting the film thickness of the coating film under the above conditions, the size variation of the pattern obtained by exposing and developing the coating film exceeds 0.005 μm, that is, the size of the pattern formation prohibited region. That is, the size is smaller than the size of the forbidden region by the pattern formed by using the coating film having the film thickness set to the maximum value of the standing wave curve Sw used in the conventional coating.

The minimum value when the film thickness of the coating film is around 6.78 is 7.
The size of the prohibited area of pattern formation when 00 (maximum value of the size distribution of the pattern caused by the standing wave effect) 20
Since the value is smaller than μm, the thickness of the coating film is 6.78.
It is also possible to set the film thickness in the vicinity.

The relationship between the size of the prohibited area and the film thickness of the coating film shown in FIG. 4 can be obtained by the above-described simulation. That is, the coating thickness distribution at the step position x is obtained by the above simulation, and the pattern dimension y at the step position x, for example, the line width of the line pattern is obtained. Next, the dimensional variation is obtained from the obtained value of the pattern dimension y. Here, the dimensional variation is simply obtained as, for example, a difference between the maximum value y _max of the pattern dimension y and the minimum value y _min of the pattern dimension y. Usually, when the standard dimension value is y _s , y _max ≧ y _s
≧ y _min . Alternatively, the variation in the pattern size may be defined in the same manner as described above.

The line width distribution of the pattern in the step portion thus obtained is found for each film thickness of the coating film, and the pattern formation is prohibited in the region where the line width variation in the line width distribution exceeds 0.005 μm. By making the area
The relationship shown in FIG. 4 is obtained.

Next, the film thickness of the resist film was set in consideration of the period of the standing wave effect having the effect of the step difference obtained in the second embodiment, and the prohibited area for pattern formation was obtained by an experiment. In this experiment, a resist film was formed as a coating film by a spin coating method on the surface of the substrate on which a step having a width of 150 μm was formed in the radial direction of the substrate. As the resist, for example, a novolac-based resist was used. The applied resist film has a standing wave curve Sw.
So that the film thickness is at a position shifted by 0.150 in the + direction from the maximum value of
It was applied so that the film thickness was 800 nm, but the film was applied so that the film thickness was 800 nm.

As a result, the pattern formation prohibited area in the lower portion Sb of the step became 10 μm. On the other hand, when the film thickness of the resist film is set to the maximum value of the standing wave curve as in the conventional case, the pattern formation prohibited region in the lower part Sb of the step becomes 20 μm. Therefore, from the experimental results, it can be said that the pattern prohibited area can be reduced by setting the range of the film thickness of the coating film as in the second embodiment.

[0080]

As described above, according to the invention described in claim 1, the thickness of the coating film is from +0.01 to +0.10 of the period from the maximum value of the period of the standing wave curve. Since the film thickness value is set at a position shifted in the range, the variation in the film thickness of the coating film caused by the step is taken into consideration to reduce the variation in the dimension (line width) of the pattern formed by the coating film in the step portion. It will be possible.

According to the second aspect of the invention, the thickness of the coating film is from the maximum value of the period of the standing wave curve to +0.
Since the film thickness value is set to a shifted position within the range of 10 or more and +0.30 or less, the pattern formation of the coating film in the step portion is prohibited in consideration of the film thickness variation of the coating film caused by the step. It is possible to reduce the area.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a first embodiment according to the present invention.

FIG. 2 is an explanatory diagram of a simulation.

FIG. 3 is a size distribution diagram of a pattern by simulation.

FIG. 4 is an explanatory diagram of the first embodiment of the present invention.

FIG. 5 is a relationship diagram between resist pattern dimensions and resist film thickness.

[Explanation of symbols]

 Sw standing wave curve

Claims (2)

[Claims] 1. A method for forming a coating film, which is formed by applying a coating liquid on the substrate surface having a step on the substrate surface by spin coating and the width of the step is 100 μm or less, Is within a range of +0.01 or more and +0.10 or less of the period of the standing wave curve from the maximum value of the standing wave curve that represents the pattern dimension that periodically changes according to the change in the thickness of the coating film. A method of forming a coating film, wherein the film thickness value is set at a position shifted by. 2. A method for forming a coating film, which is formed by applying a coating solution to the surface of a substrate having a step on the surface of the substrate by spin coating and the width of the step is 100 μm or more and less than the radius of the substrate. In the above, the film thickness of the coating film is from a maximum value of the standing wave curve representing a pattern dimension that periodically changes according to a change in the film thickness of the coating film to +0.10 or more of the period of the standing wave curve +0. A method of forming a coating film, wherein the film thickness values at the shifted positions are set within a range of 30 or less.