JPH1030170A - Vacuum thin film forming device and production of reflection mirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a reflection mirror having a high accurate reflection surface shape and a vacuum thin film forming device usable for production of the reflection mirror. SOLUTION: This vacuum thin film forming device forms thin films on a substrate 4 arranged in a vacuum vessel. In such a case, the device has at least a mechanism for rotating and holding the substrate 4, an evaporating source for evaporating the material of the thin films and a film thickness correcting member 2 for shielding a part of the evaporated particles 6a generated from the evaporating source 1 and heading toward the substrate 4. This film thickness correcting member 2 is provided with contour parts of prescribed shapes and the device is provided with a driving mechanism 3 having a function to rectilinearly move the film thickness correcting member 2 in a prescribed direction by imparting the speed distribution having a correlation with the desired film thickness distribution by which the thin films having the desired film thickness distribution are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a reflecting mirror having a highly accurate reflecting surface shape, and a vacuum thin film forming apparatus that can be used for manufacturing the reflecting mirror. The present invention is particularly suitable for transferring a circuit pattern on a photomask (mask or reticle) onto a substrate such as a wafer via a projection imaging optical system by a mirror projection system using an X-ray optical system. A method of manufacturing a reflecting mirror serving as a substrate on which an X-ray reflecting multilayer film is formed when manufacturing a multilayer X-ray reflecting mirror used in an X-ray projection exposure apparatus, a method of manufacturing the multilayer X-ray reflecting mirror, and the reflection method The present invention relates to a vacuum thin film forming apparatus that can be used for manufacturing mirrors and X-ray reflecting mirrors.

[0002]

2. Description of the Related Art A lens is mainly used for an optical element in a visible light region, but a conventional lens cannot be used in an X-ray wavelength region because the refractive index of a substance is close to one. Therefore, in the X-ray wavelength region, a reflecting mirror is used as an optical element. Furthermore, a multi-layer X-ray reflecting mirror (X-ray reflecting multi-layer provided on the reflecting surface of the reflecting mirror) capable of reflecting X-rays incident in a state close to direct incidence with a relatively high reflectance.
Is used.

One of the applications of the multilayer X-ray reflector is an exposure apparatus for manufacturing semiconductors. 2. Description of the Related Art An exposure apparatus for manufacturing a semiconductor is configured to project and transfer a circuit pattern formed on a photomask (hereinafter, referred to as a mask) surface as an object surface onto a substrate such as a wafer via an imaging device. A resist is applied to the substrate, and the resist is exposed by exposure to light, and a resist pattern is obtained.

[0004] The resolution w of the exposure apparatus is determined mainly by the exposure wavelength λ and the numerical aperture NA of the imaging optical system, and is expressed by the following equation. w = kλ / NA k: constant Therefore, in order to improve the resolving power of the exposure apparatus, it is necessary to shorten the wavelength or increase the numerical aperture. At present, the exposure apparatus used for manufacturing semiconductors mainly uses i-rays having a wavelength of 365 nm, and has a numerical aperture of about 0.5.
, A resolution of 0.4 μm is obtained.

Since it is difficult to increase the numerical aperture in terms of optical design, it is necessary to shorten the wavelength of exposure light in order to improve the resolution. Examples of the exposure light having a wavelength shorter than the i-line include an excimer laser, and KrF
(Wavelength 248nm) 0.25μm, ArF (wavelength 193nm)
A resolution of 0.18 μm is obtained. When X-rays having a shorter wavelength are used as exposure light, for example, 0.1 μm at a wavelength of 13 nm is used.
m or less.

In order for the exposure apparatus to have a desired resolution, at least the imaging optical system needs to be an optical system having no or almost no aberration. That is, if there is an aberration in the imaging optical system, the resist pattern is not formed, or the cross-sectional shape of the resist pattern is deteriorated, adversely affecting a process after exposure, and causing a problem that an image is distorted. .

The aberration (rms value) of about one-fourth of the wavelength or less is required as the aberration for obtaining the same performance as the no aberration. Therefore, as the wavelength becomes shorter, the value of the aberration must be made smaller. For example, when the exposure light is i-line, the aberration needs to be about 26 nmrms or less. In order to manufacture an optical system having no aberration or having the same performance as that of no aberration, the shape of each optical element constituting the optical system must be processed as designed. The allowable upper limit of the shape error is at least smaller than the aberration, and the upper limit of the shape error decreases as the number of optical elements increases.

In the case where all the optical elements are lenses, assuming that the number of refraction surfaces is N, the shape error has to be about 1 / N ^1/2 or less of the aberration. For example, in the case where the exposure light is i-line, if the number of refraction surfaces is 30, the allowable upper limit of the shape error is about 5 nmrms. As described above, in order to produce an aberration-free optical system, an optical element with high shape accuracy is necessary.However, until now, high-precision grinding or polishing processing has Could be produced.

However, if the wavelength of the exposure light is shortened in order to improve the resolution of the exposure apparatus, the allowable upper limit of the aberration is reduced accordingly. For example, in the case of an X-ray projection exposure apparatus using X-rays as exposure light, the X-ray wavelength is set to 13 nm.
Then, the allowable upper limit of the aberration is about 1 nmrms. This value is much smaller than the allowable upper limit of the aberration at the i-line (about 26 nmrms). Therefore, an optical element used in the X-ray projection exposure apparatus is required to have higher shape accuracy.

In the case of this X-ray projection exposure apparatus, it is preferable that the imaging optical system is a reflection optical system composed entirely of reflecting mirrors. In addition, it has a performance close to no aberration and 30m
In order to obtain an imaging optical system having a visual field of about m, at least four reflecting mirrors are necessary from the viewpoint of optical design. Further, in the case of a reduction optical system, it is difficult to reduce aberrations in a wide field of view with a spherical optical system, so an aspherical optical system is required. As the aspherical optical system, for example, an optical system obtained by improving an Offner type optical system can be mentioned, and a desired aberration can be obtained in a visual field of an orbicular zone having a length of 30 mm or more. In this case, the reflection surface shape is a rotationally symmetric aspherical surface.

Here, when there is a shape error in the reflecting surface of the reflecting mirror, light incident on the reflecting mirror is reflected at a position shifted in the optical axis direction by an amount corresponding to the shape error from an ideal reflecting position. Therefore, the optical path of the reflected light becomes longer or shorter by twice the amount of deviation of the reflection position. Therefore, the allowable upper limit value of the shape error of the reflecting surface in the reduced image forming optical system (reflective optical system) of the X-ray projection exposure apparatus is half of the allowable upper limit value of the aberration generated by each reflecting mirror. Therefore, assuming that the number of reflecting surfaces is N, the required shape error is 1 / N ^1/2 × (1/2) of the aberration.
Becomes For example, if the number of reflecting surfaces is 4, the allowable upper limit of the shape error at a wavelength of 13 nm is 0.23 nmrms.

When a multilayer X-ray mirror is used as an optical element in an X-ray exposure apparatus, the multilayer X-ray mirror must be manufactured with high precision. In order to manufacture a high-precision multilayer X-ray reflecting mirror, first, it is necessary to manufacture a substrate (or a reflecting mirror serving as a substrate) having a high-precision surface shape. If the X-ray reflection multilayer film is coated on the reflection surface of the reflection mirror, a highly accurate multilayer X-ray reflection mirror can be manufactured.

A conventional reflecting mirror or a substrate (or a reflecting mirror serving as a substrate) is manufactured by performing mechanical processing such as polishing with high precision, and more specifically, by repeating mechanical processing and shape measurement, The shape of the reflecting surface was gradually brought closer to the desired shape, and finally a reflecting surface having a desired shape was to be obtained. However, in a machining method such as polishing, it is necessary to produce a highly accurate reflecting surface shape required for a reflecting mirror or a substrate (or a reflecting mirror serving as a substrate) of an optical system of an X-ray projection exposure apparatus as described above. It was very difficult. In particular, a highly accurate aspherical reflecting surface shape could not be produced.

Therefore, as a method of manufacturing a reflecting mirror having a highly accurate reflecting surface shape, a thin film is formed on a surface of a substrate having a surface shape having a shape error with respect to a desired reflecting surface shape by a vacuum thin film forming apparatus. A method of obtaining a desired reflection surface shape by controlling the film thickness distribution and forming the film has been implemented. FIG. 9 is a block diagram showing a configuration (part) of a conventional vacuum thin film forming apparatus (one example) used in such a manufacturing method.

This vacuum thin film forming apparatus includes at least a thin film evaporation source 11, a substrate 14 holding mechanism 15, and an evaporation source 11
And a rotation mechanism 13 for rotating the substrate 14 on its own. Evaporated particles 16a are emitted from the evaporation source 11, reach the substrate 14 via the thickness correction member 12, and are stacked on the substrate. The film thickness correction member 12 controls the spatial distribution of the evaporated particles moving from the evaporation source 11 to the substrate 14.

As shown in FIG. 10, the film thickness correcting member 12
An opening is provided in a part of a metal plate or the like.
And the evaporation source 11. That is, the film thickness correction member 12 has a function of capturing a part of the incident evaporation particles 16a and converting the distribution of the evaporation particles 16b after passing through the member 12 into a desired distribution. When a film is formed using the vacuum thin film forming apparatus of FIG. 9, a part of the evaporated particles 16 a is captured by the film thickness correction member 12 and does not reach the substrate 14. Therefore, by rotating the substrate 14 during film formation, a thin film 17 having a center-symmetric film thickness distribution as shown in FIG. 11 is formed.

Here, the distribution of the evaporated particles reaching the substrate 14 depends on the edge 1 of the film thickness correcting member 12 as shown in FIG.
It is controlled by adjusting the shape of 2a. In this way, by forming a thin film on the surface of a substrate having a surface shape having a shape error with respect to a desired reflection surface shape by controlling the film thickness distribution, a reflector having a small shape error can be manufactured. it can.

[0018]

In this method, since the film thickness correction member is fixed, the film thickness becomes an amount corresponding to the circumferential aperture ratio of the film thickness correction member, and the aperture ratio changes in the radial direction. By changing the thickness, a desired film thickness distribution is obtained. However, if there is an error in the shape of the edge 12a, the film thickness increases or decreases below a desired value, and the error amount of the film thickness is proportional to the ratio of the edge shape error amount to the circumferential opening length. Will do.

Therefore, near the rotation center of the substrate, an edge shape error greatly affects a film thickness error. As a result, there is a problem that an error occurs in the shape of the substrate or the reflecting mirror. Furthermore, in order to obtain a desired film thickness distribution in the conventional manufacturing method, it is necessary to make the shape of the end 12a of the film thickness correcting member 12 into a curve.

However, when the film thickness correcting member is machined by machining or the like, an error occurs in its shape, and particularly, it is difficult to machine a curved shape with high accuracy. There is a problem in that it is not possible to control the film thickness distribution, and only a substrate or a reflector having a large shape error can be manufactured. Further, even if an optical element is manufactured by forming a multilayer film on a substrate having a large shape error manufactured by a conventional method, aberrations increase, and a desired resolution cannot be obtained. Was.

The present invention has been made in view of the above problems, and provides a method of manufacturing a reflecting mirror having a highly accurate reflecting surface shape, and a vacuum thin film forming apparatus that can be used for manufacturing the reflecting mirror. With the goal. Further, the present invention particularly relates to X
A method of manufacturing a reflecting mirror which is a substrate on which an X-ray reflecting multilayer film is formed when manufacturing a multilayer X-ray reflecting mirror used in a X-ray projection exposure apparatus; a method of manufacturing the multilayer X-ray reflecting mirror; It is an object of the present invention to provide a vacuum thin film forming apparatus that can be used for manufacturing a reflecting mirror.

[0022]

Therefore, the present invention firstly provides a vacuum thin film forming apparatus for forming a thin film on a substrate arranged in a vacuum vessel.
A vacuum thin film forming apparatus comprising: a holding mechanism; an evaporation source for evaporating the material of the thin film; and a thickness correction member for shielding a part of the evaporated particles emitted from the evaporation source toward the substrate. By providing a driving mechanism having a function of moving the film thickness correcting member in a predetermined direction with a velocity distribution correlated with a desired film thickness distribution. A vacuum thin film forming apparatus (Claim 1) characterized in that a thin film having a film thickness distribution of (1) can be formed.

The second aspect of the present invention is a vacuum thin film forming apparatus for forming a thin film on a substrate disposed in a vacuum vessel, wherein at least a mechanism for rotating and holding the substrate and a material for the thin film are evaporated. An evaporation source, and a vacuum thin film forming apparatus including a film thickness correction member that shields a part of the evaporation particles emitted from the evaporation source toward the substrate, wherein the film thickness correction member is provided with a contour portion having a predetermined shape, and A thin film having the desired film thickness distribution can be formed by providing a driving mechanism having a function of causing the rotation / holding mechanism to move straight in a predetermined direction with a speed distribution correlated with a desired film thickness distribution. A vacuum thin film forming apparatus (Claim 2) characterized by the above is provided.

Further, the present invention provides, in a third aspect, a vacuum thin film forming apparatus according to claim 1 or 2, wherein the film thickness correcting member is arranged close to the rotation / holding mechanism. Item 3) "is provided. The present invention also provides a vacuum thin film forming apparatus according to any one of claims 1 to 3, wherein the film thickness correcting member is a plate-shaped member, and the contour portion has a linear shape. Item 4) "is provided.

The present invention also has a fifth aspect that “at least a step of preparing a substrate having a reflection surface shape similar to a desired reflection surface shape, a step of installing the substrate in a rotation / holding mechanism, A step of obtaining a shape difference distribution between the reflection surface shape and the reflection surface shape of the substrate; and providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method to form the desired reflection surface shape. A step of shielding a part of the evaporating particles emitted from the evaporation source toward the substrate, and providing a film thickness correction member having a contour portion of a predetermined shape, and attaching the film thickness correction member to the thin film layer. During the film formation, by moving straight in a predetermined direction with a velocity distribution having a correlation with the shape difference distribution, a film thickness distribution corresponding to the shape difference distribution on the reflecting surface of the rotating substrate. Forming a thin film layer having Provides a process for manufacturing the reflector with Jo reflecting surface, a method of manufacturing a reflector (Claim 5) "equipped with.

The present invention is also directed to a sixth aspect of the present invention which comprises at least a step of preparing a substrate having a reflection surface shape similar to a desired reflection surface shape, a step of installing the substrate on a rotating / holding mechanism, A step of obtaining a shape difference distribution between the reflection surface shape and the reflection surface shape of the substrate; and providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method to form the desired reflection surface shape. A step of providing a film thickness correction member having a contoured portion having a predetermined shape, which is a member for shielding a part of the evaporated particles emitted from the evaporation source toward the substrate, and forming the substrate on the thin film layer. A thin film having a film thickness distribution corresponding to the shape difference distribution on the reflecting surface of the rotating substrate by moving straight in a predetermined direction with a velocity distribution correlated with the shape difference distribution in the film. Form the layer to the desired shape Method for manufacturing a reflecting mirror and a step of fabricating the reflecting mirror having a reflecting surface to provide a (claim 6). "

In a seventh aspect of the present invention, there is provided a manufacturing method according to the fifth or sixth aspect, wherein the film thickness correcting member is arranged close to the substrate. provide. An eighth aspect of the present invention is directed to the manufacturing method according to any one of claims 5 to 7, wherein the film thickness correction member is a plate-shaped member, and the contour portion has a linear shape. )"I will provide a.

In a ninth aspect of the present invention, "i, j, and N are integers, and a projection line of the contour portion of the film thickness correction member viewed from the evaporation source on the substrate is a rotation axis of the substrate. The travel time of the film thickness correction member at each point obtained by equally dividing the moving distance R when scanning the film thickness correction member so as to move from the position to the position of the length R is represented by a vector T = (t _i ). =
(T ₁ , t ₂ ,..., T _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the substrate surface, and is an integral multiple of R / N. The thickness of the thin film layer on a plurality of concentric circles having a radius is defined as a vector Y = (y _i ) = (y ₁ , y ₂ ,..., Y _N ),
The deposition rate of the thin film layer is k, and the matrix A is A = (a _{i, j} ) a _{i, j} = 0 (i <j) a _{i, j} = (k / π) cos ^-1 ｛(j− 1) / (i-1 /
2) When 膜厚 (i ≧ j), and the inverse matrix of the matrix A is A ⁻¹ , the film thickness correction member is moved such that the stay time T satisfies T = A ⁻¹ Y. The manufacturing method according to claim 8 (claim 9) "is provided.

[0029] In the present invention, the tenth is that "i, j, N are integers, and the projection line of the contour portion of the film thickness correction member viewed from the evaporation source on the substrate is the rotation axis of the substrate. The travel time of the film thickness correction member at each point obtained by equally dividing the moving distance R when scanning the film thickness correction member so as to move from the position to the position of the length R is represented by a vector T = (t _i ). =
(T ₁ , t ₂ ,..., T _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the substrate surface, and is an integral multiple of R / N. The thickness of the thin film layer on a plurality of concentric circles having a radius is defined as a vector Y = (y _i ) = (y ₁ , y ₂ ,..., Y _N ),
The deposition rate of the thin film layer is k, and the matrix B is B = (b _{i, j} ) b _{i, j} = k (i ≦ N−j) b _{i, j} = (k / π) cos ⁻¹ ｛( j−N) / (i−1 /
2) When｝ (i> N−j), and the inverse matrix of the matrix B is B ⁻¹ , the film thickness correction member is moved so that the stay time T satisfies T = B ⁻¹ Y. A manufacturing method according to claim 8 (claim 10) "is provided.

In the eleventh aspect of the present invention, it is preferable that the desired shape is an aspherical surface, and the reflection surface shape of the substrate is a spherical surface or an aspherical surface approximate to the aspherical surface. To (10) (claim 11). In addition, the present invention provides a twelfth aspect of the present invention, which is to manufacture an X-ray reflecting mirror which is an X-ray reflecting mirror by further providing an X-ray reflecting multilayer film on a reflecting surface of the reflecting mirror manufactured by the manufacturing method according to claims 5 to 11. A method (claim 12) is provided.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS At least a mechanism for rotating and holding a substrate, an evaporation source for evaporating a material of a thin film,
According to the vacuum thin film forming apparatus including a film thickness correction member that shields a part of the evaporated particles emitted from the evaporation source toward the substrate, the film thickness correction member is provided with a contour portion having a predetermined shape, and A thin film having the desired film thickness distribution can be formed by providing a drive mechanism having a function of causing the film thickness correction member to move straight in a predetermined direction with a speed distribution correlated with the desired film thickness distribution ( Claim 1).

Further, according to the present invention, at least a mechanism for rotating and holding the substrate, an evaporation source for evaporating the material of the thin film, and a film thickness correction for shielding a part of the evaporated particles emitted from the evaporation source toward the substrate. According to the vacuum thin film forming apparatus provided with the member, a contour portion of a predetermined shape is provided on the film thickness correction member,
The thin film having the desired film thickness distribution is formed by providing a drive mechanism having a function of causing the rotation / holding mechanism to move straight in a predetermined direction with a speed distribution correlated with the desired film thickness distribution. (Claim 2).

Therefore, using the vacuum thin film forming apparatus according to the present invention, a substrate having a reflection surface shape similar to a desired reflection surface shape is provided on a substrate having a reflection surface shape similar to the desired reflection surface shape. By providing a thin film layer having a film thickness distribution corresponding to the above, a reflecting mirror having a highly accurate reflecting surface shape can be manufactured. Note that the reflector that can be manufactured includes a reflector that is a substrate on which an X-ray reflective multilayer film is formed when a multilayer X-ray reflector used in an X-ray projection exposure apparatus is manufactured.

The film thickness correcting member according to the present invention is preferably arranged close to the rotation / holding mechanism in order to easily control the film thickness distribution.
Further, it is preferable that the film thickness correcting member according to the present invention is a member having a flat plate shape, and the contour portion has a linear shape (claims 4 and 8). With such a configuration,
High-precision processing of contour shapes and members becomes easy.

Further, according to the present invention, a step of preparing a substrate having at least a reflection surface shape similar to a desired reflection surface shape, a step of installing the substrate on a rotating / holding mechanism, and a step of providing the desired reflection surface Obtaining a shape difference distribution between the shape and the reflection surface shape of the substrate, and providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method to form the desired reflection surface shape. A member that shields a part of the evaporated particles emitted from the evaporation source toward the substrate, and a film thickness correction member having a contour portion having a predetermined shape is provided, and the film thickness correction member is formed of the thin film layer. A thin film having a film thickness distribution corresponding to the shape difference distribution on the reflecting surface of the rotating substrate by moving straight in a predetermined direction with a velocity distribution correlated with the shape difference distribution in the film. Forming a layer, Manufacturing a reflecting mirror having a reflecting surface in a shape of, the method according to the method for manufacturing a reflecting mirror, the substrate having a reflecting surface shape close to the desired reflecting surface shape, the desired reflecting surface shape and the It is possible to provide a thin film layer having a film thickness distribution corresponding to the shape difference distribution of the reflection surface shape of the substrate, and as a result, it is possible to manufacture a reflection mirror having a highly accurate reflection surface shape. ).

[0036] Further, according to the present invention, a step of preparing a substrate having at least a reflection surface shape similar to a desired reflection surface shape, a step of installing the substrate on a rotating / holding mechanism, and a step of: Obtaining a shape difference distribution between the shape and the reflection surface shape of the substrate, and providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method to form the desired reflection surface shape. A film thickness correction member having a contoured portion of a predetermined shape, which is a member for shielding a part of evaporating particles emitted from the evaporation source toward the substrate, and forming the substrate on the thin film layer. The thin film layer having a film thickness distribution corresponding to the shape difference distribution is formed on the reflecting surface of the rotating substrate by moving straight in a predetermined direction with a velocity distribution having a correlation with the shape difference distribution. Form the desired shape Manufacturing a reflecting mirror having a reflecting surface, and a method of manufacturing a reflecting mirror including the reflecting mirror, the substrate having a reflecting surface shape similar to the desired reflecting surface shape, the desired reflecting surface shape and the substrate It is possible to provide a thin film layer having a film thickness distribution corresponding to the shape difference distribution of the reflecting surface shape, and as a result, it is possible to manufacture a reflecting mirror having a highly accurate reflecting surface shape.

The mirrors that can be manufactured include X-rays used for manufacturing a multilayer X-ray mirror used in an X-ray projection exposure apparatus.
A reflecting mirror serving as a substrate on which the line reflective multilayer film is formed is also included.
Further, in the manufacturing method according to the present invention, “i, j,
N is an integer, and the film thickness correction is performed such that a projection line of the contour portion of the film thickness correction member viewed from the evaporation source onto the substrate moves from a rotation axis position of the substrate to a position of length R. The stay time of the film thickness correction member at each point obtained by equally dividing the movement distance R when scanning the member by N is represented by a vector T = (t
_i ) = (t ₁ , t ₂ ,..., t _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the substrate surface, and R / N A vector Y = (y _i ) = (y ₁ , y ₂ ,..., Y _N ) on the plurality of concentric circles having a radius of an integral multiple.
And the film formation rate of the thin film layer is k, and the matrix A is A = (a _{i, j} ) a _{i, j} = 0 (i <j) a _{i, j} = (k / π) cos ⁻¹ } ( j-1) / (i-1 /
2) When｝ (i ≧ j), and the inverse matrix of the matrix A is A ⁻¹ , the film thickness correction member is moved so that the stay time T satisfies T = A ⁻¹ Y ” This is preferable because a reflecting mirror having a highly accurate reflecting surface shape can be manufactured.

Further, in the manufacturing method according to the present invention, it is preferable that “i, j, N be integers, and a projection line of the contour portion of the film thickness correction member on the substrate viewed from the evaporation source be formed on the substrate. When the film thickness correction member is scanned so as to move from the rotation axis position to the position of the length R, the stay time of the film thickness correction member at each point obtained by dividing the movement distance R by N is represented by a vector T = ( t _i ) = (t ₁ , t ₂ ,..., t _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the substrate surface, and R / N The thickness of the thin film layer on a plurality of concentric orbits having a radius of an integral multiple of the vector Y = (y _i ) = (y ₁ , y ₂ ,
.., Y _N ), the deposition rate of the thin film layer is k, and the matrix B is B = (bi _{, j} ) bi _{, j} = k (i ≦ N−j) bi _{, j} = ( k / π) cos ^-1 ｛(j−N) / (i−1 /
2) Move the film thickness correction member so that the stay time T satisfies T = B ^-1 Y when ^させ る (i> N−j) and the inverse matrix of the matrix B is B ^−1. Thus, it is possible to manufacture a reflecting mirror having a more accurate reflecting surface shape, which is also preferable (claim 10).

The method of manufacturing a reflecting mirror according to the present invention is preferably used when the desired shape is an aspherical surface and the reflecting surface shape of the substrate is a spherical surface or an aspherical surface similar to the aspherical surface. There is (claim 11). In particular, when a substrate having a reflective surface shape of a spherical surface is used, the spherical substrate can be processed with high precision by mechanical processing such as polishing, so if the film is formed by controlling the film thickness distribution with high precision by the manufacturing method according to the present invention. Thus, it is possible to manufacture a reflecting mirror having a more accurate aspherical reflecting surface shape.

Further, an X-ray reflecting mirror can be manufactured by further providing an X-ray reflecting multilayer film on the reflecting surface of the reflecting mirror manufactured by the manufacturing method according to claims 5 to 11 (claim 12). Further, by combining a plurality of the X-ray reflecting mirrors, it is possible to form an X-ray optical system having no or almost no aberration. The evaporation source according to the present invention is preferably one capable of controlling the film deposition rate with high accuracy in controlling the film thickness distribution with high accuracy according to the present invention. For example, a sputtering source such as an ion beam or an EB evaporation source may be used. Evaporation sources are preferred.

It is preferable that the drive mechanism according to the present invention is capable of controlling the position and movement of the film thickness correcting member or the substrate rotating / holding mechanism with high precision. In the present invention, a mechanism capable of measuring the surface (reflection surface) shape of the substrate during film formation may be provided (not shown). By providing such a mechanism, by monitoring in real time the reflection surface shape of the substrate during the formation of the thin film, the change in the shape error from the desired reflection surface shape is tracked, and the value is set to zero. By controlling the film formation and the driving, the desired reflection surface shape can be formed more accurately.

Here, a vacuum thin film forming apparatus (one example) according to the present invention, and a reflecting mirror using the apparatus (for example, an X-ray for manufacturing a multilayer X-ray reflecting mirror used in an X-ray projection exposure apparatus) A method (one example) of manufacturing a reflecting mirror serving as a substrate for forming a reflective multilayer film will be described (see FIGS. 1 and 2). First, FIG.
The vacuum thin film forming apparatus of the present invention comprises at least a rotation / holding mechanism 5 for the substrate 4, an evaporation source 1 for evaporating the material of the thin film, and a film thickness correction for shielding a part of the evaporation particles emitted from the evaporation source toward the substrate 4. A member 2 and a drive mechanism 3 for controlling the position of the film thickness correcting member 2 are provided.

Here, the film thickness correcting member 2 is disposed between the evaporation source 1 and the substrate 4, and the driving mechanism 3 has a speed distribution correlated with a desired film thickness distribution, and It has a function of moving the member straight in a predetermined direction. Evaporated particles 6a are emitted from the evaporation source 1, and reach the substrate 4 via the film thickness correcting member 2 to be laminated (formed). The substrate 4 has a reflection surface shape similar to a desired reflection surface shape.

The film thickness correcting member 2 and the driving mechanism 3 are for controlling the spatial distribution of the evaporated particles which are emitted from the evaporation source 1 and move to the substrate 4. It is possible to obtain a desired distribution of the evaporated particles 6b after capturing a part thereof and passing through the film thickness correcting member 2. The film thickness correcting member 2 is made of a material that shields the evaporated particles, and has a shape of a flat plate having at least one end (contour portion) 2a as shown in FIG. 3, for example.

Of the evaporated particles 6a emitted from the evaporation source 1,
The evaporated particles 6b not shielded by the film thickness correction member 2 reach the substrate 4 and are stacked (formed). Conversely, the evaporated particles shielded by the film thickness correction member 2 do not reach the substrate 4. Therefore, the evaporating particles cannot reach the shielded portion near the member 2 on the substrate surface. In other words, a thin film is deposited (deposited) only on a part of the substrate 4, and the processing amount (deposition amount) of that part can be increased.

Then, while the substrate 4 is rotated by the rotation / holding mechanism 5 during the film formation, the position of the film thickness correction member 2 is moved by the drive mechanism 3 so as to have a velocity distribution correlated with the desired film thickness distribution. Then, the spatial distribution of the evaporating particles 6b reaching the substrate 4 is changed over time to form a thin film layer having a desired film thickness distribution on the reflection surface of the substrate 4.

At this time, it is preferable to scan the film thickness correction member 2 substantially parallel to the surface of the substrate 4 because the film thickness distribution can be easily controlled. FIG. 4 (cross-sectional view) shows an example of forming a thin film layer in this manner. For example, the drive mechanism 3 moves the film thickness correction member 2 from the center of the substrate 4 to the end of FIG.
By scanning in the order shown in (a), (b), and (c), a film is formed on the entire surface of the substrate.

At this time, since the film thickness distribution of the thin film layer can be controlled by the scanning speed of the film thickness correcting member 2, a desired surface shape can be obtained. That is, a desired film thickness distribution (a film thickness distribution corresponding to a shape difference distribution between the desired reflecting surface shape and the reflecting surface shape of the substrate) is formed on the reflecting surface of the substrate having a reflecting surface shape similar to the desired reflecting surface shape. ) Can be formed to produce a reflecting mirror having a reflecting surface of a desired shape (a highly accurate reflecting surface). Next, the vacuum thin film forming apparatus of FIG. 2 includes at least a rotation / holding mechanism 5 for the substrate 4, an evaporation source 1 for evaporating the material of the thin film, and a part of the evaporated particles emitted from the evaporation source toward the substrate 4. Thickness correction member 2 to be shielded, and drive mechanism 7 for controlling the position of substrate 4
Having.

Here, the film thickness correction member 2 is disposed between the evaporation source 1 and the substrate 4, and the driving mechanism 7 controls the substrate 4 to a predetermined speed distribution having a correlation with a desired film thickness distribution. It has the function of moving straight in the direction. Evaporated particles 6a are emitted from the evaporation source 1, and reach the substrate 4 via the film thickness correcting member 2 to be laminated (formed). The substrate 4 has a reflection surface shape similar to a desired reflection surface shape.

The film thickness correcting member 2 and the driving mechanism 7 are for controlling the spatial distribution of the evaporated particles which are emitted from the evaporation source 1 and move to the substrate 4. It is possible to obtain a desired distribution of the evaporated particles 6b after capturing a part thereof and passing through the film thickness correcting member 2. The film thickness correcting member 2 is made of a material that shields the evaporated particles, and has a shape of a flat plate having at least one end (contour portion) 2a as shown in FIG. 3, for example.

Of the evaporated particles 6a emitted from the evaporation source 1,
The evaporated particles 6b not shielded by the film thickness correction member 2 reach the substrate 4 and are stacked (formed). Conversely, the evaporated particles shielded by the film thickness correction member 2 do not reach the substrate 4. Therefore, the evaporating particles cannot reach the shielded portion near the member 2 on the substrate surface. In other words, a thin film is deposited (deposited) only on a part of the substrate 4, and the processing amount (deposition amount) of that part can be increased.

Then, while the substrate 4 is rotated by the rotation and holding mechanism 5 during the film formation, the position of the substrate 4 is moved by the driving mechanism 7 so as to have a velocity distribution correlated with a desired film thickness distribution. By changing the position on the substrate 4 where the evaporating particles 6b reach sequentially with time, a thin film layer having a desired film thickness distribution can be formed on the reflection surface of the substrate 4. At this time, it is preferable to scan the substrate 4 substantially parallel to the surface of the film thickness correction member 2 because the film thickness distribution can be easily controlled.

FIG. 4 shows an example of forming a thin film layer in this manner.
(Cross-sectional view). For example, the driving mechanism 7 controls the substrate 4
From the position where half of the substrate surface is on the film thickness correction member 2 to the position where the entire substrate surface is on the film thickness correction member 2 in FIG.
By scanning in the order shown in (a), (b), and (c), a film is formed on the entire surface of the substrate. At this time, the thickness distribution of the thin film layer can be controlled by the scanning speed of the substrate 4, so that a desired surface shape can be obtained.

That is, a desired film thickness distribution (corresponding to a shape difference distribution between the desired reflecting surface shape and the reflecting surface shape of the substrate) is formed on the reflecting surface of the substrate having a reflecting surface shape similar to the desired reflecting surface shape. By forming a thin film layer having a (thickness distribution), a reflecting mirror having a reflecting surface of a desired shape (a highly accurate reflecting surface) can be manufactured. The film thickness correcting member 2 according to the present invention may be manufactured by machining or the like, and it is preferable that the shape of the contour portion 2a be processed with high precision. As described above, if the film thickness correction member is a flat plate-shaped member and the contour portion is a linear shape, high-precision processing of the contour shape and the member becomes easy.

FIG. 5 shows an example of processing the linear contour 2a. When the contour 2a is planarly polished with the film thickness correcting member 2 sandwiched between the auxiliary members 9, the contour 2a is polished linearly. Since planar polishing can easily perform high-precision processing as compared with processing of a curved surface or the like, the contour portion 2a has a high-precision linear shape. Next, using a film thickness correction member having a linear contour,
A method for obtaining a desired film thickness distribution according to the present invention will be specifically described below.

As shown in FIG. 6, on the surface of the substrate 4 having a radius R, a plurality of concentric annular zones in which a circle having a radius R is equally divided into N in the radial direction are considered. Th
・ ・ It is the Nth ring zone. The projection line of the contour portion 2a on the substrate is moved N steps at equal intervals from the rotation axis position of the substrate 4 to the position of the length R (outer circumference) in proximity to the substrate 4, Let the stay time of the step be t _j (j is an integer equal to or less than N).

Since the outer radius of the i-th annular zone (i is an integer equal to or less than N) is i / N × R, if the radius of the center of the annular zone is the radius r _i of the i-th annular zone, then r _i = (I-1 / 2) R
/ N. When the film thickness correcting member 2 is at the j-th step (when the contour of the member 2 is in contact with the inner periphery of the j-th annular zone), the position l _j of the contour 2a of the member 2 is represented by l _j = (j− 1) Assuming that R / N, at this time, in the i-th annular zone, the angle θ _{i, j} (hereinafter referred to as the opening angle) of the arc of the region where the film is attached is θ _{i, j} = 2 cos ⁻¹ (l _j / R _i ) = 2 cos ^-1 {(j-1) / (i-1 / 2)} (i ≧
j) θ _{i, j} = 0 (i <j).

[0058] When the deposition rate and k, the thickness of the film deposited on the i-th ring-shaped zone y ^o _{i, j} is _{^{y o i, j = 0 (}} i <j) y o i, j = k (θ _{i, j) t j / 2π} = (k / π) cos -1 {(j-1) / (i-1/2)}
(I ≧ j).

When i is smaller than j, the whole annular zone is shielded by the film thickness correcting member 2, so that the aperture angle becomes 0 and no film is deposited. Accordingly, when the member 2 is moved from the center of the substrate to the position of the N-th annular zone, the thickness y _i of the film deposited on the i-th annular zone is Becomes Here, two vectors Y and T are defined as Y = y _i =
(Y ₁ , y ₂ ,... Y _N ), T = t _i = (t ₁ ,
t ₂ ,..., t _N ), and the matrix A is A = (a _{i, j} ) a _{i, j} = 0 (i <j) a _{i, j} = (k / π) cos ⁻¹ ｛(j -1) / (i-1 /
2) If｝ (i ≧ j), then Y = AT.

This equation gives the relationship between the way of moving the film thickness correction member and the film thickness distribution of the thin film. Therefore, assuming that the inverse matrix of the matrix A is A ⁻¹ , when the member is moved with the residence time T of the film thickness correction member satisfying T = A ⁻¹ Y, a desired film thickness distribution Y is obtained. As a result, a reflector and a substrate having desired shapes can be manufactured. Then, the scanning speed of the film thickness correction member for obtaining the desired film thickness distribution Y can be calculated from these equations.

The case where the film thickness correction member is scanned from the center of the substrate to the outside has been described above. In this case, the film thickness monotonically increases from the center of the substrate to the outside. On the other hand, when the thickness correction member is scanned from the outside of the substrate toward the center,
The film thickness monotonically decreases from the center of the substrate toward the outside. Hereinafter, how to move the film thickness correction member in this case will be described.

As shown in FIG. 7, on the surface of the substrate 4 having a radius R, a plurality of concentric annular zones in which a circle having a radius R is equally divided into N in the radial direction are considered. Th
・ ・ It is the Nth ring zone. The film thickness correction member 2 is moved close to the substrate 4 by N steps at regular intervals from the outer periphery of the substrate 4 to the position of the rotation axis by moving the projection line of the contour portion 2a onto the substrate, and the stay time of each step is t. _j (j is an integer less than or equal to N)
And

Since the outer radius of the i-th annular zone (i is an integer equal to or less than N) is i / N × R, if the radius of the center of the annular zone is the radius r _i of the i-th annular zone, then r _i = (I-1 / 2) R
/ N. When the film thickness correction member 2 is at the j-th step (when the contour of the member 2 is in contact with the inner periphery of the (N-j) th annular zone), the position l _j of the contour 2a of the member 2 is represented by l _j = ( N−j) R / N, then, in the i-th annular zone, the angle θ _{i, j} of the arc of the region where the film is attached is θ _{i, j} = 2 cos ⁻¹ (−l _j / r _i ) = 2 cos ^-1 {(j-N) / (i-1 / 2)} (i>
N−j) θ _{i, j} = 2π (i ≦ N−j).

Assuming that the deposition rate is k, the thickness y ^oi _{, j} of the film deposited on the i-th annular zone is ^yo _{i, j} = kt _j (i ≦ N−j) ^yo _{i, j} = k (θ _{i, j} ) t _j / 2π = (k / π) cos ^-1 {(j−N) / (i−1 / 2)}
(I> N−j).

When i is equal to or smaller than Nj, the i-th orbicular zone is not shielded by the film thickness correcting member 2, so that the aperture angle becomes 2π and the film forming speed becomes k. Therefore, the member 2 is moved from the center of the substrate by N
The thickness y _i of the film deposited on the i-th annular zone when moved to the position of the i-th annular zone is Becomes Here, two vectors Y and T are defined as Y = y _i =
(Y ₁ , y ₂ ,... Y _N ), T = t _i = (t ₁ ,
t ₂ ,..., t _N ), and the matrix B is B = (b _{i, j} ) b _{i, j} = k (i ≦ N−j) b _{i, j} = (k / π) cos ⁻¹ } (J−N) / (i−1 /
2) If｝ (i> N−j), Y = BT.

This equation gives the relation between the way of moving the film thickness correction member and the film thickness distribution of the thin film. Therefore, assuming that the inverse matrix of the matrix B is B ⁻¹ , when the member is moved at the residence time T of the member that satisfies T = B ⁻¹ Y, a desired film thickness distribution Y is obtained,
As a result, a reflector and a substrate having desired shapes can be manufactured. Then, it is possible to calculate how to move the film thickness correction member to obtain a desired film thickness distribution Y from these equations.

As described above, according to the present invention,
When the thickness correction member is moved from the center of the substrate to the outside, the film thickness monotonically increases from the center of the substrate to the outside.When the member is moved from the outside of the substrate to the center, the film thickness moves from the center of the substrate to the outside. It decreases monotonically toward. Furthermore, an arbitrary film thickness distribution can be realized by combining these movements.

When the film thickness correcting member is moved stepwise, the opening angle in each ring zone changes stepwise, for example, as shown by a curve 1 in FIG. Therefore, in order to change the opening angle approximately equal to the curve 2 in FIG. 8, the thickness correction member may be scanned continuously instead of stepwise. For example, instead of the member staying at the j-th step position, the member may be moved at a constant speed from the j-th step position to the (j + 1) -th step position at a speed such that the moving time is equal to the staying time, The thickness correction member may be scanned while the moving speed is continuously changed so that the change of the curve describes the curve 2.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0070]

Embodiment 1 FIG. 1 is a schematic configuration diagram showing a partial configuration of a vacuum thin film forming apparatus of the present embodiment. The vacuum thin film forming apparatus shown in FIG. 1 includes at least a rotation / holding mechanism 5 for a substrate 4, an evaporation source 1 for evaporating a material of the thin film, and a film for shielding a part of evaporated particles emitted from the evaporation source toward the substrate 4. Thickness correction member 2,
And a drive mechanism 3 for controlling the position of the film thickness correction member 2.

As the evaporation source, an ion beam sputtering source capable of controlling the film thickness with a high degree of accuracy (film formation speed control) was used. Substrate 4
Has a spherical surface and a diameter of 30 manufactured by polishing.
A mm quartz substrate was used. The film thickness compensating member 2 is disposed between the evaporation source 1 and the substrate 4 in close proximity to the substrate 4, and a driving mechanism 3
Has a velocity distribution that is correlated with the desired film thickness distribution,
It has a function of moving the film thickness correcting member straight in a predetermined direction.

The film thickness correction member 2 has a thickness of 1 mm, 50 × 10
It is a stainless steel flat plate of 0 mm (rectangle), and its end (contour) 2a has a linear shape. The drive mechanism 3 that controls the position of the film thickness correction member 2 is a scan stage, and can scan the member 2 in a desired one direction. Using this apparatus, a thin film of SiO ₂ was formed on the substrate 4. At the time of film formation, first, the projection line on the substrate at the end 2a of the film thickness correction member 2 is arranged near the center of the substrate 4, and then the substrate 4 is rotated as shown in FIG. The scanning was performed in a direction in which the end 2a approached the peripheral portion of the substrate 4 while the edge 2a approached.

The desired film thickness distribution was obtained by controlling the scanning speed of the film thickness correcting member 2 to control the film thickness distribution. Prior to film formation, a film thickness distribution capable of reducing the surface shape error to a desired value or less and a scanning speed of the member 2 for obtaining such a film thickness distribution have been calculated in advance. When the surface shape of the substrate processed in this manner was measured by an interferometer, the substrate had a desired aspherical shape, and the surface shape error was 0.2 nmrms or less.

Further, when a multilayer film was formed on this substrate to form a multilayer film reflector, and an imaging optical system was constructed with four similarly prepared multilayer film mirrors, the wavefront aberration was 1 nmrms or less. Further, an X-ray projection exposure apparatus was manufactured using this optical system, and the resist was exposed. As a result, a resist pattern having a pattern size of 0.1 μm was obtained.

On the other hand, when a soft X-ray projection exposure apparatus was manufactured using a reflecting mirror manufactured by a conventional vacuum thin film forming apparatus and the resist was exposed, a resist pattern having a pattern size of 0.1 μm could not be obtained.

[0076]

Embodiment 2 FIG. 2 is a schematic configuration diagram showing a partial configuration of a vacuum thin film forming apparatus of the present embodiment. The vacuum thin film forming apparatus shown in FIG. 2 includes at least a rotating / holding mechanism 5 for the substrate 4, an evaporation source 1 for evaporating the material of the thin film, and a film for shielding a part of the evaporated particles emitted from the evaporation source toward the substrate 4. Thickness correction member 2,
And a drive mechanism 7 for controlling the position of the substrate 4.

As the evaporation source, an ion beam sputtering source capable of controlling the film thickness with a high degree of accuracy (film forming speed control) was used. Substrate 4
Has a spherical surface and a diameter of 30 manufactured by polishing.
A mm quartz substrate was used. The film thickness compensating member 2 is disposed between the evaporation source 1 and the substrate 4 in close proximity to the substrate 4, and a driving mechanism 7
Has a velocity distribution that is correlated with the desired film thickness distribution,
It has a function of moving the substrate rotation / holding mechanism 5 straight in a predetermined direction.

The film thickness correcting member 2 has a thickness of 1 mm, 50 × 10
It is a stainless steel flat plate of 0 mm (rectangle), and its end (contour) 2a has a linear shape. The drive mechanism 7 for controlling the position of the substrate 4 is a scan stage, and can scan the substrate 4 in one desired direction. Using this apparatus, a thin film of SiO ₂ was formed on the substrate 4. At the time of film formation, the substrate 4 is first arranged so that the projection line of the end 2a of the shielding member onto the substrate is near the center of the substrate 4, and then, while rotating the substrate 4 as shown in FIG. End 2a
Scans in such a direction that it approaches the periphery of the substrate 4.

The desired film thickness distribution was obtained by controlling the scanning speed of the substrate 4 to control the film thickness distribution. Further, a film thickness distribution capable of reducing a surface shape error to a desired value or less before film formation, and a substrate 4 for obtaining such a film thickness distribution.
Was calculated in advance. When the surface shape of the substrate processed in this way was measured with an interferometer, the substrate had a desired aspherical shape, and the surface shape error was 0.2%.
nmrms or less.

Further, when a multilayer film was formed on this substrate to form a multilayer film reflector, and an imaging optical system was constituted by four similarly manufactured multilayer film mirrors, the wavefront aberration was 1 nmrms or less. Further, an X-ray projection exposure apparatus was manufactured using this optical system, and the resist was exposed. As a result, a resist pattern having a pattern size of 0.1 μm was obtained.

On the other hand, when a soft X-ray projection exposure apparatus was manufactured using a reflecting mirror manufactured by a conventional vacuum thin film forming apparatus and the resist was exposed, a resist pattern having a pattern size of 0.1 μm could not be obtained. In the above embodiment, the substrate for the multilayer reflector that requires a very high-precision shape is a target for film formation. However, the substrate can be applied to other substrates,
For example, it goes without saying that a reflection surface having a desired shape can be similarly formed by using a total reflection mirror for X-rays having a shape error or a reflection mirror for an excimer laser stepper as a substrate.

[0082]

As described above, according to the vacuum thin film forming apparatus of the present invention, a thin film having a desired film thickness distribution can be formed. In addition, using the vacuum thin film forming apparatus according to the present invention, a substrate having a reflection surface shape similar to a desired reflection surface shape corresponds to a shape difference distribution between the desired reflection surface shape and the reflection surface shape of the substrate. When a thin film layer having a film thickness distribution is provided, a reflecting mirror having a highly accurate reflecting surface shape can be manufactured.

Further, according to the method for manufacturing a reflecting mirror of the present invention, a reflecting mirror having a highly accurate reflecting surface shape (for example, a substrate for forming an X-ray reflecting multilayer film when manufacturing a multilayer X-ray reflecting mirror) And a multilayer X-ray reflecting mirror can be manufactured. Further, the X-ray projection exposure apparatus provided with the multilayer X-ray reflecting mirror manufactured according to the present invention has a high resolution, and as a result, it is possible to faithfully transfer the mask pattern onto the substrate with high throughput.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a partial configuration of a vacuum thin film forming apparatus according to a first embodiment.

FIG. 2 is a schematic configuration diagram illustrating a partial configuration of a vacuum thin film forming apparatus according to a second embodiment.

FIG. 3 is a plan view showing an example of a film thickness correction member according to the present invention.

4A and 4B are conceptual diagrams showing an example of film formation according to the present invention. FIGS. 4A, 4B, and 4C show another example in which a film thickness correction member or a substrate is scanned to scan another portion from one end of the substrate. This shows how a film having a desired film thickness distribution is formed at the end.

FIG. 5 is a perspective view showing a processing example of processing an end portion (contour portion) of the film thickness correcting member according to the present invention into a linear shape.

FIG. 6 is an explanatory diagram showing a positional relationship between the substrate and the film thickness correction member when the film thickness correction member is moved from the rotation center of the substrate to the outer periphery.

FIG. 7 is an explanatory diagram showing a positional relationship between the substrate and the film thickness correction member when the film thickness correction member is moved from the outer periphery of the substrate to the center of rotation.

FIG. 8 is a data diagram showing a change of an opening angle in each orbicular zone.

FIG. 9 is a schematic configuration diagram showing a partial configuration of a conventional vacuum thin film forming apparatus used for manufacturing a reflecting mirror and a substrate.

FIG. 10 is a plan view showing an example of a conventional film thickness correction member.

FIG. 11 is a sectional view of a reflecting mirror (substrate) manufactured using a conventional vacuum thin film forming apparatus.

[Description of Signs of Main Parts]

 DESCRIPTION OF SYMBOLS 1 ... Evaporation source 2 ... Film thickness correction member 2a ... Edge part (outline part) of film thickness correction member 3 ... Drive mechanism of film thickness correction member 4 ... Substrate 5 ... Substrate Rotation / holding mechanism 6a, 6b Evaporated particles 7 Substrate drive mechanism 8 Thin film 9 Auxiliary member 11 Evaporation source 12 Film thickness correction member 12a End (edge) of opening 13: substrate rotating mechanism 14: substrate 15: holding mechanism 16a, 16b: evaporated particles 17: thin film

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location H01L 21/027 H01L 21/30 531Z

Claims (12)

[Claims] 1. A vacuum thin film forming apparatus for forming a thin film on a substrate disposed in a vacuum vessel, comprising at least a mechanism for rotating and holding the substrate, an evaporation source for evaporating a material of the thin film, and the evaporation source In a vacuum thin film forming apparatus provided with a thickness correction member that shields a part of the evaporating particles emitted from and toward the substrate, a contour portion of a predetermined shape is provided on the thickness correction member, and
A thin film having the desired film thickness distribution can be formed by providing a drive mechanism having a function of causing the film thickness correction member to move straight in a predetermined direction with a speed distribution correlated with the desired film thickness distribution. A vacuum thin film forming apparatus characterized in that: 2. A vacuum thin film forming apparatus for forming a thin film on a substrate disposed in a vacuum container, comprising at least a mechanism for rotating and holding the substrate, an evaporation source for evaporating a material of the thin film, and the evaporation source In a vacuum thin film forming apparatus provided with a thickness correction member that shields a part of the evaporating particles emitted from and toward the substrate, a contour portion of a predetermined shape is provided on the thickness correction member, and
A thin film having the desired film thickness distribution can be formed by providing a driving mechanism having a function of causing the rotation / holding mechanism to have a speed distribution correlated with a desired film thickness distribution and to move in a predetermined direction. A vacuum thin film forming apparatus characterized in that: 3. The apparatus according to claim 1, wherein the film thickness correction member is disposed close to the rotation / holding mechanism.
Or the vacuum thin film forming apparatus according to 2. 4. The vacuum thin film forming apparatus according to claim 1, wherein said film thickness correction member is a plate-shaped member, and said contour portion is linear. 5. A step of preparing at least a substrate having a reflection surface shape close to a desired reflection surface shape; a step of installing the substrate on a rotation / holding mechanism; A step of obtaining a shape difference distribution of the reflection surface shape, and a step of forming a desired reflection surface shape by providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method. A member that shields a part of the evaporating particles emitted from the substrate toward the substrate, and a film thickness correction member having a contour portion of a predetermined shape is provided, and the film thickness correction member is formed during the formation of the thin film layer. By forming a thin film layer having a film thickness distribution corresponding to the shape difference distribution on the reflecting surface of the rotating substrate by moving straight in a predetermined direction with a speed distribution having a correlation with the shape difference distribution. Has a reflective surface of desired shape Method for manufacturing a reflecting mirror and a step of fabricating the reflector. 6. A step of preparing at least a substrate having a reflection surface shape similar to a desired reflection surface shape; a step of installing the substrate on a rotation / holding mechanism; A step of obtaining a shape difference distribution of the reflection surface shape, and a step of forming a desired reflection surface shape by providing a thin film layer having a film thickness distribution on the reflection surface of the substrate by a vacuum thin film forming method. A film thickness correction member having a contoured portion of a predetermined shape, which is a member for shielding a part of the evaporating particles emitted from the substrate toward the substrate, and wherein the substrate has a shape difference during the film formation of the thin film layer. By moving straight ahead in a predetermined direction with a velocity distribution having a correlation with the distribution, a thin film layer having a film thickness distribution corresponding to the shape difference distribution is formed on the reflecting surface of the rotating substrate. Anti-reflection with reflective surface Method for producing a reflector comprising the steps of: preparing a mirror, a. 7. The manufacturing method according to claim 5, wherein the film thickness correction member is arranged close to the substrate. 8. The method according to claim 5, wherein said film thickness correction member is a plate-shaped member, and said contour portion is linear. 9. A projection line on the substrate of the contour portion of the film thickness correction member viewed from the evaporation source, where i, j, and N are integers, and a position of a length R from a rotation axis position of the substrate. The travel time of the film thickness correction member at each point obtained by dividing the movement distance R when scanning the film thickness correction member so as to move to N is represented by a vector T = (t _i ) = (t ₁ ,
t ₂ ,..., t _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the surface of the substrate and has a radius equal to an integral multiple of R / N. The film thickness of the thin film layer on the plurality of orbicular zones is represented by a vector Y =
(Y _i ) = (y ₁ , y ₂ ,..., Y _N ), the deposition rate of the thin film layer is k, and the matrix A is A = (a _{i, j} ) a _{i, j} = 0 ( i <j) a _{i, j} = (k / π) cos ^-1 ｛(j-1) / (i-1 /
2) When 膜厚 (i ≧ j), and the inverse matrix of the matrix A is A ⁻¹ , the film thickness correction member is moved such that the stay time T satisfies T = A ⁻¹ Y. The manufacturing method according to claim 8, wherein 10. i, j, and N are integers, and a projection line of the contour portion of the film thickness correction member on the substrate as viewed from the evaporation source is a position having a length R from a rotation axis position of the substrate. The travel time of the film thickness correction member at each point obtained by dividing the moving distance R when scanning the film thickness correction member so as to move to N is represented by a vector T = (t _i ) = (t ₁ , t _2). ,…,
t _N ), and when the radius of the substrate is R, it is a concentric circle centered on the rotation axis on the substrate surface,
The film thickness of the thin film layer on a plurality of concentric orbits having a radius that is an integral multiple of R / N is represented by a vector Y = (y _i ) =
(Y ₁ , y ₂ ,..., Y _N ), the deposition rate of the thin film layer is k, and the matrix B is B = (b _{i, j} ) b _{i, j} = k (i ≦ N−j) ) B _{i, j} = (k / π) cos ^-1 ｛(j−N) / (i−1 /
2) When｝ (i> N−j), and the inverse matrix of the matrix B is B ⁻¹ , the film thickness correction member is moved so that the stay time T satisfies T = B ⁻¹ Y. The method according to claim 8, wherein: 11. The manufacturing method according to claim 5, wherein the desired shape is an aspherical surface, and a reflection surface shape of the substrate is a spherical surface or an aspherical surface approximate to the aspherical surface. 12. A method of manufacturing an X-ray reflecting mirror, wherein an X-ray reflecting mirror is formed by further providing an X-ray reflecting multilayer film on a reflecting surface of the reflecting mirror manufactured by the manufacturing method according to claim 5.