JPH1171671A - Vacuum deposition device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form thin film having a uniform coating thickness even onto a substrate to be deposited having a spherical face as the face to be deposited. SOLUTION: A primary substrate holder 4 is supported in a vacuum chamber 104 so as to rotate around a primary virtual axis 26 as the center, and a secondary substrate holder 6 is supported by the primary substrate holder 4 in such a state as to rotate around a secondary virtual axis 24 inclined at an angle of 20 or 60 degrees to the primary virtual axis 26 and extended. A substrate 20 on which surface thin coating shall be formed in made direct its spherical face to be deposited in the lower direction and is arranged at the place of an opening 18 formed on a rotary plate 16 being the secondary substrate holder 6. When the primary substrate holder 4 is rotatively driven by a motor 128, the rotary plate 16 whose tooth part formed on its outer circumference is meshed with a pinion 28 fixed to the vacuum chamber 104 also makes the primary substrate holder rotate 4 while being rotated with the primary substrate holder 4. An evaporating means 106 is arranged at a position deviated from the center in the vacuum chamber 104.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum evaporation apparatus for forming a thin film on a substrate surface by vacuum evaporation, and more particularly to a vacuum evaporation apparatus for forming a thin film on a substrate having a spherical evaporation surface such as a lens. .

[0002]

2. Description of the Related Art Conventionally, there is known a vacuum deposition method in which a thin film is formed by evaporating an evaporation source made of a deposition material in a vacuum atmosphere and attaching vapor to a surface of an object to be deposited. For example, in the field of manufacturing optical components, an antireflection film, a reflection increasing film, an optical filter film, and the like are formed on a glass substrate by the vacuum deposition method. As a method of forming a thin film, in addition to the vacuum evaporation method, a sputtering method or a CVD method is used.
Although the method is known, especially when forming a multilayer film, the vacuum evaporation method is excellent in terms of easy film thickness control, high film forming speed, simplicity of the device configuration, and the like, Widely used.

FIG. 5 is a sectional side view showing an example of a conventional vacuum deposition apparatus for performing a vacuum deposition method. As shown in FIG. 5, the vacuum deposition apparatus 102 includes a vacuum chamber 10
4. Evaporating means 106, substrate holder 108, motor 128
Etc. An exhaust port 114 is formed on the side wall near the bottom of the vacuum chamber 104, and the inside of the vacuum chamber 104 is evacuated by a vacuum pump (not shown) through the exhaust port 114 to maintain a necessary vacuum state. You. Evaporating means 106 is provided at substantially the center of the bottom surface of the vacuum chamber 104. Evaporation means 106
Is a crucible 116, its shutter 118, an electron gun 120
It is comprised including. The crucible 116 is filled with a vapor deposition material that is an evaporation source, and the shutter 118 is arranged close to the upper part thereof.

The shutter 118 has a size covering the upper part of the crucible 116, and is rotatably supported by a rotating column 119. Then, the rotation position of the shutter 118 is changed by rotating the rotating column 119 by a motor (not shown), and the shutter 118 is opened and closed. That is, when the shutter 118 is opened,
Is a position deviated from the upper part of the crucible 116, and when the shutter 118 is closed, the shutter 118
Is the position above the crucible 116 (the position in FIG. 5). An electron gun 120 is disposed on the side of the crucible 116, and electrons emitted from the electron gun 120 are indicated by a dotted line a.
As shown by, the vapor deposition material evaporates by being incident on the vapor deposition material in the crucible 116.

[0005] The substrate holder 108 is formed in a disk shape, and has a large number of openings 124 formed therein. A rotation shaft 126 is fixed substantially vertically to the center of the upper surface of the substrate holder 108, and the substrate holder 108 is supported by the rotation shaft 126, and is disposed above the vacuum chamber 104 with the lower surface facing the evaporating means 106. I have. The rotating shaft 126 is provided in the vacuum chamber 1
The upper end of the vacuum chamber 104 is connected to the output shaft of a motor 128 which is rotatably supported by being inserted through a hole 105 formed in the ceiling of the vacuum chamber 104. In addition,
An O-ring 127 is provided between the rotation shaft 126 and the hole 105.
To ensure airtightness.

[0006] The vacuum vapor deposition apparatus 102 thus configured
In forming a thin film on the surface of a substrate such as a glass substrate forming an optical component, for example, the substrate 154 to be vapor-deposited is
In a state where the lower surface is exposed downward through the opening 124, each is locked and arranged in the opening 124, and power is supplied to the motor 128 to rotate the substrate holder 108. Next, power is supplied to a motor (not shown) to rotate the shutter 118 by a predetermined angle to set the shutter 118 to the open state. As a result, the vapor of the vapor deposition material in the crucible 116 is released from the crucible 116, rises in the vacuum chamber 104, and
8 adheres through the opening 124 to the surface of the base 154 supported by 8 to form a thin film.

Although the vapor of the vapor deposition material is not necessarily distributed at a uniform density in the vacuum chamber 104, a thin film having a substantially uniform thickness is formed on any of the substrates 154 because the substrate holder 108 is rotated. However, since the evaporating means 106 is disposed substantially at the center in the vacuum chamber 104, the vapor density is low at the peripheral portion of the substrate holder 108, and the substrate 154 disposed at the central portion of the substrate holder 108
There is a case where the thickness of the thin film formed differs between the substrate and the base 154 disposed in the peripheral portion. Therefore, the base holder 10
A film thickness correction plate having a different width in the radial direction of the base holder 108 is arranged below the substrate holder 8, so that the film thickness is often made uniform.

[0008]

By the way, in such a vacuum evaporation apparatus 102, when the evaporation surface of the base 154 is flat or nearly flat, the vapor from the evaporating means 106 emits the evaporation surface of each base 154. Is almost perpendicular to the substrate 154, so that a thin film is formed with a substantially uniform thickness regardless of the location on the base 154. However, when the substrate 154 to be vapor-deposited is, for example, a convex lens and the vapor-deposited surface is spherical as shown in FIG. In the part, the light enters the surface obliquely. Therefore, the thickness of the thin film formed on the peripheral portion is small, and it is difficult to form a thin film with a uniform thickness on the surface of the base 154.

That is, in the conventional vacuum vapor deposition apparatus, a thin film cannot be formed with a uniform film thickness on a vapor-deposited substrate having a spherical vapor deposition surface, and an optical component having necessary optical characteristics is manufactured. It was difficult. An object of the present invention is to solve such a problem, and to form a thin film with a uniform film thickness regardless of the position on the evaporation surface even on a deposition substrate having a spherical evaporation surface. It is to provide a device.

[0010]

According to the present invention, in order to achieve the above object, a plurality of substrates are supported in a vacuum chamber, and a vapor deposition material is evaporated from an evaporation source disposed below the substrates to form the substrates. In a vacuum evaporation apparatus for forming a thin film on the surface of the base by attaching the thin film to a surface,
A first base holder supported in the vacuum chamber so as to be rotatable about a virtual axis, and rotatable about a second virtual axis extending at an angle to the first virtual axis. The second substrate holder supported by the first substrate holder in a suitable state, and supporting the substrate with the vapor deposition surface of the substrate oriented substantially in the same direction as the extending direction of the second virtual axis. A substrate supporting portion provided on the second substrate holder, first driving means for driving the first substrate holder to rotate, and second driving means for driving the second substrate holder to rotate. It is characterized by having.

Further, the present invention is characterized in that the evaporation source is arranged at a position deviated laterally from the first virtual axis at the bottom of the vacuum chamber. Further, the present invention is characterized in that the vacuum chamber has a column shape centered on the first virtual axis, and the evaporation source is arranged at a position near the outer periphery of the bottom of the vacuum chamber. Also,
The present invention is characterized in that the second virtual axis extends obliquely at an angle of 20 degrees to 60 degrees with respect to the first virtual axis.

Further, according to the present invention, the second virtual axis is
It is characterized by being inclined at an angle of 40 degrees to 55 degrees with respect to the first virtual axis. Further, the invention is characterized in that a plurality of second base holders are supported on the first base holder. Also, in the present invention, the first base holder is formed in a hollow conical shape that is convex upward and open at a lower portion about the first virtual axis, and a plurality of circular first openings are formed in the first circular shape. A plurality of base holders are formed at intervals in a circumferential direction of the base holder, and the second base holder is configured by a rotating plate having a circular shape in a plan view and rotatably fitted and supported in the second opening; The virtual axis passes through the center of the first opening.

Further, according to the present invention, a tooth portion is formed on an outer periphery of the second base holder, and a second driving means is provided with the first driving means.
A pinion which is fixed in the vacuum chamber so as to substantially coincide with the center of the virtual axis, and meshes with a tooth portion of the second base holder at an upper portion of the first base holder. Also, in the present invention, a plurality of second openings are formed in the second base holder at intervals in a circumferential direction of the second base holder, and the base support portion is provided with the second openings. Wherein the base is disposed in each of the second openings such that the lower surface is exposed downward. Also, in the present invention, the first driving means may be a first driving means.
A rotating shaft extending upward from the upper end of the base holder through the inside of the pinion on the first virtual axis, and a motor disposed outside the vacuum chamber and rotating the rotating shaft. It is characterized by being. Also, the present invention
The surface of the substrate on which the thin film is formed is spherical.

In the vacuum vapor deposition apparatus according to the present invention, each substrate is supported by the second substrate holder, and the respective vapor deposition surfaces are inclined in the extending direction of the second virtual axis. Not only does the whole rotate with one substrate holder, but also around a second virtual axis with the second substrate holder. Therefore, the vapor of the vapor deposition material from the evaporation source is obliquely incident on the central portion of each substrate while changing the angle, even if the vapor deposition surface of the substrate is spherical.
The light is also obliquely incident on the peripheral portion of the base while changing the angle. Therefore, in the present invention, a thin film having a uniform thickness can be formed on the deposition surface of the substrate regardless of the location. As a result, it is possible to manufacture an optical component such as a convex lens having the necessary optical characteristics over the entire surface. Further, in the present invention, since the evaporation source is disposed at a position deviated laterally from the first virtual axis, the vapor of the vapor deposition material enters the substrate more obliquely, and has a uniform thickness. This is even more advantageous in forming a thin film having a small thickness.

[0015]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a sectional side view showing an example of the vacuum evaporation apparatus according to the present invention, and FIG. 2 is a sectional view taken along line FF 'of FIG. In the drawing, the same elements as those of the vacuum evaporation apparatus shown in FIG. 5 are denoted by the same reference numerals, and a detailed description thereof will be omitted here. The vacuum deposition apparatus 2 according to the present embodiment includes a first substrate holder 4, a second substrate holder 6 supported by the first substrate holder 4, and first and second substrate holders 4 and 6 for driving the first and second substrate holders 4, 6, respectively. It is configured to include first and second driving means 8 and 10, and the like. The first base holder 4 is formed in the shape of a hollow cone with a convex upward and an open lower part, and the center of the cone is arranged so as to coincide with the center of the rotary shaft 126, and a portion corresponding to the top of the cone is substantially vertical. Is fixed to the lower end of the rotating shaft 126. In the first base holder 4, four openings 12 (equivalent to the first openings in the claims) having a circular shape in a plan view are formed at equal intervals around the center of the first base holder 4. . At the lower edge of each opening 12, at a location on the lower surface of the first base holder 4,
A step 14 (FIG. 1) protruding in the center direction is formed, and the upper surface of the step 14 contacts the lower surface of the second substrate holder 6 to support the second substrate holder 6 fitted in the opening 12. Is done. The diameter of the opening 12 is such that the second base holder 6 having a circular shape in a plan view fits into the opening 12 and has no backlash and can rotate smoothly.

The second substrate holder 6 specifically includes the rotating plate 1
The rotary plate 16 is formed with four openings 18 (equivalent to the second openings in the claims) at equal intervals around the center thereof. Each opening 18 forms a base supporting portion, and each base 20 is disposed at the position of the opening 18 with its lower surface exposed downward through the opening 18. Each opening 18
A step 22 protruding in the center direction is formed at a location on the lower surface side of the rotating plate 16 at the edge of the rotary plate 16.
The inner diameter at the two points is smaller than the diameter of the base 20. Therefore, the base 20 disposed at the location of the opening 18 is supported at the location of the opening 18 without falling. A tooth portion 21 is formed on the entire outer periphery of the rotating plate 16.

The first base holder 4 is formed in a conical shape as described above, and the rotary plate 16 forming the second base holder 6 is fitted into the opening 12 formed in the first base holder 4. Therefore, the second virtual axis 2 which is the center of rotation of the rotating plate 16
The reference numeral 4 extends obliquely with respect to a first virtual axis 26 (the center line of the rotation shaft 126) which is the center of rotation of the first base holder 4. In the present embodiment, the rotating plate 1
6, that is, the angle θ formed by the first base holder 4 with respect to the horizontal is 20 degrees to 60 degrees, preferably 40 degrees to 5 degrees.
By tilting by 5 degrees, the first and second virtual axes 2
6, 24 is set to 20 degrees to 60 degrees, preferably 40 degrees to 55 degrees.

A pinion 28 is disposed at the top of the first base holder 4 with the rotating shaft 126 inside and the center coinciding with the center of the rotating shaft 126, and fixed to the ceiling of the vacuum chamber. Have been. The pinion 28 is a kind of bevel gear, and its teeth mesh with the teeth 21 of the rotary plate 16 protruding from the upper surface of the first base holder 4. The tooth portions 21 formed on the pinion 28 and the rotating plate 16,
Further, the second driving means 1 according to the present invention is driven by the first base holder 4 and the motor 128 which is the first driving means 8.
0 is configured.

The evaporating means 106 provided on the floor of the vacuum chamber 104 is not a central part of the vacuum chamber 104,
It is arranged at a position deviated laterally from the first virtual axis 26, in this embodiment, at a position near the outer periphery of the vacuum chamber 104.

Next, the operation of the vacuum evaporation apparatus 2 configured as described above will be described. First, 16 bases 20 on which a thin film is to be formed on the surface are placed in each opening 1 of the four rotating plates 16.
8 places. As shown in FIG. 1, each base 20 has one surface formed into a spherical shape, and is arranged with the spherical surface side down such that the spherical surface side is exposed downward through the opening 18.

Then, in this state, power is supplied to the motor 128 to drive the first base holder 4 and rotate it as shown by an arrow G (FIG. 1). The rotation of the first base holder 4 causes the rotation plate 16 supported by the first base holder 4 to rotate.
Also rotates together with the first base holder 4. At this time, as the teeth 21 of the rotating plate 16 mesh with the teeth of the pinion 28, the rotating plate 16 is also driven and the second virtual axis 24 is It rotates around as shown by arrow H. On the other hand, power is supplied to a motor (not shown) to rotate the shutter 118 by a certain angle to set the shutter 118 to the open state. As a result, the vapor of the vapor deposition material in the crucible 116 is released from the crucible 116, rises in the vacuum chamber 104, and adheres to the surface of each substrate 20 supported by the rotating plate 16 to form a thin film.

In the vacuum vapor deposition apparatus 2 according to the present embodiment, each substrate 20 is supported by the rotating plate 16 inclined as described above, and each vapor deposition surface has the second virtual axis 2.
4 and in the second direction together with the rotating plate 16.
Is rotated around the virtual axis 24 of FIG. Therefore, even if the evaporating means is disposed substantially at the center in the vacuum chamber 104, the vapor of the evaporation source rising from the evaporating means 106 enters the central portion of each base 20 having a spherical evaporation surface. Increasingly obliquely incident while changing the angle,
The light also enters the peripheral portion of the base 20 obliquely while changing the incident angle. Therefore, in the present embodiment, the base 2
Variations in the thickness of the thin film due to the difference in the incident angle of the vapor with respect to 0 are reduced, and the thin film is formed on the deposition surface of the substrate 20 with a uniform thickness regardless of the location. Moreover, in the present embodiment, since the evaporating means 106 is arranged near the outer periphery in the vacuum chamber 104 deviated from the first virtual axis 26, the vapor from the evaporating means 106 is applied to each base 20. Enter in a more inclined state. Therefore, the base 2
The variation in the thickness of the thin film due to the difference in the incident angle of the vapor of the evaporation source with respect to 0 is smaller, which is more advantageous in forming the thin film with a uniform thickness on the spherical evaporation surface of the substrate 20. . The evaporating means 106 is preferably located at a position farthest from the virtual axis 26. Thereby, the base 2
In the distance between 0 and the evaporating means 106, the difference between the closest distance and the farthest distance can be made large, and the mutual rotation of the first and second base holders 4 and 6 allows the base 20 and the evaporating means 106 Since the vapor deposition is performed in a state where the distance continuously changes between the closest distance and the farthest distance, the evaporating means 106
The unevenness of the film thickness due to the non-uniformity of the distance is suppressed, which is more advantageous.

As described above, the present invention has been described based on the embodiment. However, this is merely an example, and the present invention can be implemented in various forms without being limited to this example. For example, the second base attached to the first base holder 4
The number of the substrate holders 6 and the number of the substrates 20 mounted on the second substrate holder 6 can be variously changed according to the required device specifications. Further, the shape of the first base holder 4 is not necessarily required to be conical, and any shape can be used as long as the second base holder 6 can be supported in a rotatable state and each base 20 can be supported by being inclined. It may be a shape. The present invention is of course effective not only when a single-layer film is formed on the substrate surface but also when a multi-layer film is formed.

[0024]

Next, an embodiment of a vacuum deposition apparatus according to the present invention will be described. In this embodiment, the distance A from the first virtual axis 26 to the center of the crucible 116 is 350 mm, and the height of the top of the first base holder 4 with respect to the bottom of the vacuum chamber 104 in the above-described vacuum deposition apparatus 2. 8 for B
00 mm, and the distance C from the top of the first base holder 4 to the center of the second base holder 6 (rotating plate 16) is 260 m.
m, the distance D between the centers of the two openings 18 sandwiching the center of the rotating plate 16 is 100 mm, and the first and second virtual axes 2
The angle θ formed by the first and second radiators 6 and 24 was 40 degrees. Also, the base 20
As shown in the side view of FIG.
m, the radius of curvature of the deposition surface was 15 mm, the non-deposition surface was flat, and the thickness was 15 mm.

Under the above conditions, vapor deposition was actually performed on the substrate 20, and the thickness of the thin film formed on the surface was measured.
FIG. 4A is a plan view showing a measurement position of the thin film thickness, and FIG.
Is a side view of the same. The measurement results are shown in [Table 1]. Also,
For comparison, vapor deposition was also performed on the substrate 20 having the same shape and size by the vacuum vapor deposition apparatus 102 shown in FIG. 5, and the thickness of the formed thin film was measured at the same measurement position. The measurement results are also shown in Table 1 (Comparative Example). In the vacuum deposition apparatus 102, the height B ′ of the lower surface of the base holder with respect to the bottom of the vacuum chamber 104 is 800 mm, and the base holder 1
08 to the center of the outer substrate 154
Was set to 200 mm (FIG. 5).

[0026]

[Table 1]

As can be seen from this table, in the vacuum evaporation apparatus 2, the film thickness is 391 nm to 5 at the measurement positions P1 to P5.
00 nm, and the change width is 109 nm. On the other hand, in the conventional vacuum vapor deposition apparatus 102, the film thickness is 240 nm to 500 nm at the measurement positions P1 to P5, and the variation width is 260 nm. That is, in the vacuum evaporation apparatus 2 of this embodiment, the change in the film thickness is greatly reduced.

[0028]

As described above, in the vacuum vapor deposition apparatus of the present invention, each substrate is supported by the second substrate holder, and each vapor deposition surface is inclined toward the direction in which the second virtual axis extends. Then, not only does the entire body rotate with the first base holder, but also rotates about the second virtual axis with the second base holder. Therefore, the vapor of the deposition material from the evaporation source is obliquely incident on the central portion of the base and the peripheral portion of the base while changing the incident angle, even if the deposition surface is spherical. Therefore, in the present invention, the variation in the thickness of the thin film due to the incident angle is reduced, and the thin film can be formed with a uniform thickness regardless of the location on the deposition surface of the substrate. As a result, it is possible to manufacture an optical component such as a convex lens having the necessary optical characteristics over the entire surface. Furthermore, in the present invention, since the evaporation source is disposed at a position distant to the side from the first imaginary axis, the angle of incidence of the vapor on the substrate becomes more oblique, so that a thin film having a uniform thickness can be formed. Is more advantageous.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing an example of a vacuum evaporation apparatus according to the present invention.

FIG. 2 is a sectional view taken along line F-F 'of FIG.

FIG. 3 is a side view of a base.

FIG. 4A is a plan view showing a measurement position of a thin film thickness,
(B) is the same side view.

FIG. 5 is a cross-sectional side view showing an example of a conventional vacuum deposition apparatus for performing a vacuum deposition method.

[Explanation of symbols]

 Reference Signs List 2 vacuum evaporation apparatus 4 first substrate holder 6 second substrate holder 8 first driving means 10 second driving means 12 opening (first opening) 18 opening (second opening) 16 rotating plate 20 base 28 Pinion 104 Vacuum chamber 106 Evaporation means 126 Rotation axis

Claims (11)

[Claims] 1. A method comprising: supporting a plurality of substrates in a vacuum chamber;
In a vacuum evaporation apparatus for forming a thin film on the surface of the substrate by evaporating an evaporation material from an evaporation source disposed below the substrate and attaching the evaporation material to the surface of the substrate, a substantially vertical first virtual axis is centered. A first base holder supported in the vacuum chamber in a rotatable state; and a first base holder rotatable about a second virtual axis extending at an angle to the first virtual axis. A second substrate holder supported by the first substrate holder; and the second substrate supporting the substrate with the deposition surface of the substrate oriented substantially in the same direction as the direction in which the second virtual axis extends. A substrate supporting portion provided on the substrate holder, a first driving unit that rotationally drives the first substrate holder, and a second driving unit that rotationally drives the second substrate holder. A vacuum deposition apparatus characterized by the above-mentioned. 2. The vacuum evaporation apparatus according to claim 1, wherein the evaporation source is arranged at a position deviated laterally from the first virtual axis at a bottom of the vacuum chamber. 3. The vacuum evaporation apparatus according to claim 1, wherein the vacuum chamber has a column shape centered on the first virtual axis, and the evaporation source is disposed at a position near the outer periphery of the bottom of the vacuum chamber. 4. The apparatus according to claim 1, wherein the second virtual axis extends at an angle of 20 to 60 degrees with respect to the first virtual axis. Vacuum evaporation equipment. 5. The vacuum according to claim 1, wherein the second virtual axis is inclined at an angle of 40 to 55 degrees with respect to the first virtual axis. Evaporation equipment. 6. The vacuum deposition apparatus according to claim 1, wherein a plurality of second substrate holders are supported on the first substrate holder. 7. The first base holder is formed in a hollow conical shape that is upwardly convex and opened at a lower portion about a first virtual axis, and a plurality of circular first openings are formed in the first cone. A plurality of second base holders are formed at intervals in the circumferential direction of the base holder, and the second base holder is configured by a rotating plate having a circular shape in a plan view and rotatably fitted to and supported by the second opening. The vacuum deposition apparatus according to claim 1, wherein the axis passes through the center of the first opening. 8. A toothed portion is formed on the outer periphery of the second base holder, and the second driving means is fixed in the vacuum chamber so as to substantially coincide with the center of the first virtual axis, The vacuum evaporation apparatus according to claim 7, further comprising a pinion meshing with a tooth portion of the second substrate holder above the first substrate holder. 9. A plurality of second openings are formed in said second base holder at intervals in a circumferential direction of said second base holder, and said base support portion defines said second openings. The vacuum deposition apparatus according to claim 7, wherein the base is disposed so as to include a lower surface of the base in each of the second openings such that a lower surface thereof is exposed downward. 10. A rotating shaft extending upward from a top end of a first base holder through an inside of the pinion on a first virtual axis, and disposed outside the vacuum chamber. 9. The vacuum deposition apparatus according to claim 8, further comprising a motor configured to rotate the rotating shaft. 11. The vacuum evaporation apparatus according to claim 1, wherein a surface of the substrate on which the thin film is formed has a spherical shape.