JPH10317136A - Both side simultaneous coating forming method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form thin coating such as antireflection coating on both sides of a spectacle lens without requiring a complicated inverting mechanism. SOLUTION: This is a method for simultaneously forming coating on both sides of a spectacle lens by sputtering, in which a spectacle lens is loaded onto a planar substrate holder 31 and is introduced into a vacuum treating chamber 11, and, in the vacuum treating chamber, the following (i) sputtering stage and (ii) converting stage are repeated, by which metallic compound thin coating with desired coating thickness is simultaneously formed on both sides of the spectacle lens: (i) the sputtering stage in which a target is sputtered onto the spectacle lens by using sputtering devices 41 provided on both sides of the spectacle lens to form metallic ultrathin coating composed of metal or metallic imperfect reactants respectively on both sides of the spectacle lens and (ii) the converting stage in which the metallic ultrathin coating is brought to react with a reactive gas, which is converted into ultrathin coating of metallic compounds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for simultaneously forming thin films on both surfaces of a spectacle lens in the same vacuum chamber.

[0002]

2. Description of the Related Art A spectacle lens is formed with a thin film such as an antireflection film and a protective film. In this case, it is necessary to form a thin film such as an antireflection film on both surfaces. As a method of forming a thin film such as an anti-reflection film, there are a vacuum deposition method and a sputtering method. In any case, a thin film is first formed on one side, and then a thin film is formed again on the back side.
As a general method, once a thin film is formed on one side, the film is once taken out of the vacuum chamber, the spectacle lens (substrate) is turned over and set again so that a film is formed on the back side, and the film is formed again in the vacuum chamber. There is a method, but the operation is complicated and productivity is poor. Further, there is also known an apparatus in which a thin film is formed on one side of an eyeglass lens, and then the eyeglass lens is inverted in a vacuum chamber to perform vacuum deposition on both sides without breaking a vacuum atmosphere.
However, this reversal vapor deposition apparatus has a complicated reversal mechanism, resulting in an increase in apparatus cost and a decrease in productivity.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to simultaneously form a thin film such as an antireflection film on both surfaces of an eyeglass lens by sputtering without requiring an inversion mechanism.

[0004]

The double-sided simultaneous film forming method according to the present invention is a method for simultaneously forming a film on both surfaces of an eyeglass lens by sputtering, wherein the eyeglass lens is mounted on a flat substrate holder and subjected to vacuum processing. A metal compound thin film having a desired film thickness is simultaneously formed on both surfaces of the spectacle lens by introducing the film into a chamber and repeating the following (i) sputtering step and (ii) conversion step in the vacuum processing chamber. And (I) A sputtering process in which a target is sputtered on the spectacle lens using a sputtering device provided on both sides of the spectacle lens, and a metal-based ultrathin film made of a metal or an incompletely reacted metal is formed on each side of the spectacle lens. (Ii) a conversion step of reacting a metal-based ultrathin film with a reactive gas to convert it into a metal compound ultrathin film

The double-sided simultaneous film forming apparatus of the present invention is an apparatus for simultaneously forming a film on both sides of a spectacle lens by sputtering, and is provided in a vacuum processing chamber and a vacuum processing chamber, wherein the spectacle lens is mounted. A disk-shaped substrate holder that rotates in the horizontal direction, and a sputtering device and a reactive gas supply source provided on both sides of the substrate holder, respectively. And a reactive gas supply source alternately and repeatedly, and a metal-based ultrathin film made of a metal or an incompletely reacted metal is formed on both surfaces of the spectacle lens by sputtering with a sputtering device. The gas supply source reacts the ultra-thin metallic film with the reactive gas to convert it into an ultra-thin metal compound film. Characterized in that so as to form a desired film thickness of the thin film by repeating the conversion of ultra thin films of group compound.

[0006]

FIG. 1 is a longitudinal sectional view showing an embodiment of an apparatus used in the present invention, and FIG. 2 is a sectional view (plan view) along line AA of FIG. Note that some members such as the shielding plate 51 are omitted in FIG. 2 to avoid complexity. FIG. 3 is a perspective view showing the positional relationship between the target 43 and the inductively coupled plasma generator 61 with respect to the substrate holder 31 and the spectacle lens 33. In order to avoid complication, only the above members on the lower surface side of the substrate holder 31 are shown, and the others are omitted. FIG. 4 shows a rotation mechanism of the substrate holder in this embodiment, and FIG. 5 shows a transport mechanism of the substrate holder and the film thickness correction plate. The double-sided simultaneous film forming apparatus includes an introduction chamber 83, a vacuum processing chamber 11, and a preliminary processing chamber 85.
It is composed of As shown in FIGS. 1, 2, and 3, a substrate holder 31 on which a number of spectacle lenses 33 as substrates are mounted is processed in the vacuum processing chamber 11, and an antireflection film is formed on the spectacle lenses 33.

The disc-shaped substrate holder 31 on which the spectacle lens 33 (substrate) is mounted is rotated by the rotating mechanism 21 to form a metal-based ultra-thin film on the spectacle lens 33 by a sputtering device and to form an inductively coupled plasma generator 61 ( The conversion of the metal compound thin film into an oxide thin film or the like by the reactive gas supply source) is repeated, and an ultrathin film is repeatedly deposited to form a thin film having a desired thickness. First, the substrate holder 31 on which the spectacle lens is mounted is placed on the carrier 81 and put into the introduction chamber 83, and the introduction chamber 83 is evacuated. Then, the gate valve 17 is opened, and the substrate holder 31 is transported by the transport roller 13 together with the carrier 81 into the vacuum processing chamber 11 which is also evacuated.

The substrate holder 31 is held by the rotating mechanism 21 in the vacuum processing chamber 11 as shown in FIG. The rotation mechanism 21 holds the substrate holder 31 by an upper support member 23 and a lower support member 25 driven up and down by a hydraulic cylinder or the like, and is rotated by a motor 29. The positioning of the substrate holder 31 is performed by fitting the chucking projection 27 into the center hole of the substrate holder 31. 2
7 ′ is the position (height) of the chucking projection when the substrate holder 31 mounted on the carrier 81 is carried into the vacuum processing chamber 11 from the introduction chamber 83, or the substrate holder 31 mounted on the carrier is The position of the chucking projection when being carried out from the vacuum processing chamber 11 to the preliminary vacuum chamber 85 is shown. On the other hand, at 27 ″ and 31 ″, the carrier 81 is supported by the rotation mechanism 21 after the substrate holder 31 is supported.
Or the positions of the chucking projections and the substrate holder when the carrier 81 is carried in from the preliminary vacuum chamber 85 to collect the substrate holder 31 after forming the thin film.

In the evacuated vacuum processing chamber 11, an ultra-thin film is repeatedly deposited as described above. The detailed technical contents are described in Japanese Patent Publication No. Hei 8-19518 and Japanese Patent Laid-Open Publication No. Hei 8-176821. It is described in.
The sputtering apparatus includes a sputtering electrode 41, a target 43,
It comprises a sputter power supply 45, a mass flow 47, a sputter gas cylinder 49, and a shielding plate 51. On the other hand, the inductively coupled plasma generator 61 includes a high frequency (RF) discharge chamber 63, a high frequency (RF) coil 65, and an internal magnetic field coil 6.
6, matching box 67, high frequency (RF) power supply 6
9. It is composed of a shielding plate 71. Shielding plates 51, 71
Is intended to separate and separately control a sputtering atmosphere in which argon is introduced to sputter the target 43 and a degree of vacuum and a partial pressure of gas are obtained, and a plasma atmosphere obtained by introducing a reactive gas such as oxygen gas. It is installed in. In particular, when oxygen partial pressure is increased by mixing oxygen into the argon atmosphere of the target 43, the target 43
An oxide film is formed on the surface layer of the target 43, and abnormal discharge on the surface of the target 43 increases. For this reason, the sputtering operation becomes unstable, and damage to the thin film occurs.
The above shielding plates 51 and 71 prevent the above-mentioned inconvenience by separating the sputtering atmosphere and the plasma atmosphere from each other in terms of gas type, gas partial pressure, and gas pressure (degree of vacuum) and controlling them individually.

[0010] When the substrate holder 31 is rotated by the rotating mechanism 21, the target 43 is sputtered on the front surface of the sputtering apparatus, and an ultrathin film is formed on the spectacle lens 33 of the substrate holder 31. At this time, a sputtering gas such as an argon gas is introduced from a sputtering gas cylinder through the mass flow 47, and the sputtering atmosphere is adjusted. Here, a case where a SiO ₂ thin film is finally formed will be described as an example. An ultra-thin Si film is formed on a spectacle lens (substrate) using metal Si as a target 43. Next, the spectacle lens is rotated and moved by the rotation mechanism 21 and is exposed to the plasma of oxygen introduced from the reactive gas cylinder 75 through the mass flow 73 on the front surface of the inductively coupled plasma generator 61 to convert the metal Si into SiO ₂ . It is converted to form an ultra thin film of SiO ₂ . By rotating the substrate holder 31 and repeating this operation, a plurality of ultra-thin SiO ₂ thin films are deposited, and finally a SiO ₂ thin film having a desired thickness is obtained. The term “ultra-thin film” in the present invention is a term used to prevent confusion with the final thin film because the ultra-thin film is deposited a plurality of times to form a final thin film. , Meaning that it is much thinner than the final thin film.

According to the present invention, since sputtering can be performed as metal Si instead of SiO ₂ , the sputtering speed can be increased and the efficiency is improved. In addition, target 43
Even when SiO ₂ is sputtered as above, the thin film formed by the sputtering shows SiO x (x <2) and oxygen deficiency, but according to the present invention, the oxygen deficiency is compensated for by the reactive gas from the plasma source. Thus, a stable SiO ₂ thin film can be formed. 1 and 2, one target 43, 43 is provided on each side of the substrate holder 31.
Is shown, but a plurality of targets 43 can be provided on both sides of the substrate holder 31 respectively.
As a specific example, a target such as titanium (Ti), Zr (zirconium) or Ta (tantalum) is used in combination with a Si target, and a SiO ₂ film, a TiO ₂ film, and a ZrO ₂ film are used.
A case where a multilayer antireflection film is manufactured by forming a film or a laminated film with a Ta ₂ O ₅ film is exemplified.

The inductively-coupled plasma generator 61 generates a plasma of an oxygen gas by introducing a reactive gas such as an oxygen gas or a nitrogen gas from a reactive gas cylinder 75 into a vacuum processing chamber 11 through a mass flow 73. It is. In the present invention, a reactive gas can be generated using an ion source such as an ion gun instead of such a plasma generation source. The internal magnetic field coil 66 disposed in the opening of the inductively coupled plasma generator 61 has a magnetic velocity density distribution that is axially symmetric with respect to the axis of the plasma source and diverges on the substrate surface. It is possible to control the size of a reaction region such as an oxidation reaction on the surface. Furthermore, the inductively coupled plasma generator 61 can be disposed facing the upper surface and the lower surface of the substrate holder 31 or can be disposed so as to be shifted in position. The same applies to the targets 43 on the upper and lower sides of the substrate holder 31. As described above, according to the present invention, films can be simultaneously formed on both surfaces of the spectacle lens.

After the completion of the film formation, the substrate holder 3 shown in FIG.
The carrier 81, which has been moved to the position “1” and has been waiting in the pre-evacuated preliminary vacuum chamber 85, is moved to the gate valve 15.
The substrate is carried into the vacuum processing chamber 11 by the transport rollers 13 via the, the substrate holder 31 is mounted, and is transferred into the preliminary vacuum chamber 85 and taken out. In the present invention, a film can be formed without exposing the vacuum processing chamber 11 to the atmosphere. In the present invention, since a large number of spectacle lenses 33 are mounted on the same substrate holder 31 in the same vacuum processing chamber 11 and a thin film is formed by sputtering, a uniform thin film is formed on the large number of spectacle lenses 33. It is necessary to form the film, that is, to correct the film thickness. Although there are various methods for correcting the film thickness, the following three methods are typical.

(1) As seen in FIGS. 2 and 3,
In the spectacle lens 33 mounted on the substrate holder 31, the linear velocity differs between the rotation axis side and the outer peripheral side. Therefore, the disk-shaped substrate holder 31 is placed in the vacuum processing chamber 11 around the center axis thereof so that the time when the spectacle lens 33 and the target 43 face each other is the same on the rotation axis side and the outer circumference side. And rotate it horizontally.
Is sputtered on a trapezoidal or fan-shaped target 43 whose area increases from the center toward the outer periphery. Thereby, the time during which the spectacle lenses 33 mounted on the central axis side and the outer peripheral side of the substrate holder 31 are sputtered is made uniform,
The thickness of the formed thin film becomes uniform.

(2) Adjust the strength and arrangement of the magnet installed below the target 43. Thus, the distribution of the film thickness of the substrate with respect to the target portion to be sputtered can be adjusted. Therefore, the target 43 is set to the spectacle lens 3
Even if the time at which 3 faces each other is different between the central axis side and the outer peripheral side, the thickness of the formed thin film can be made uniform.
Specifically, the state of the magnetic field formed on the target by the magnet is adjusted to control the electron confinement region, and the position of the target surface to be sputtered and the sputtering speed distribution are adjusted. FIG. 6 shows an example of this magnet arrangement, in which a magnet (S-pole) 44 and a magnet (N-pole) are provided on the lower surface of the target.
46 are arranged. Reference numeral 42 denotes a yoke.

(3) A film thickness correction plate 87 is used. The film thickness correction plate 87 partially covers the space between the target 43 and the spectacle lens 33 and reduces the thin film forming speed in the covered portion, thereby making the film thickness distribution in the diameter direction of the substrate holder 31 uniform. If a generally rectangular target is used, the central axis side where the linear velocity is slow is set to the thickness correction plates 87 and 8.
9 makes the mask larger. FIG. 7 shows a substrate holder 31 using a trapezoidal target 43.
The thickness distribution in the diameter direction is adjusted, and
It is a perspective view showing a state to be corrected by 7, 89, and in order to avoid complication, members other than those relating to film thickness correction are omitted. Note that the film thickness correction plates 87 and 89 may have different shapes as shown in FIG. 7, or may have the same shape.

Further, the repetition of the sputtering changes the consumption state of the target 43, thereby changing the amount of the target 43 to be sputtered, and changing the originally achieved film thickness distribution (uniform deposition film thickness). May be.
In such a case, as shown in FIG.
Is opened, the film thickness compensating plates 87, 89 are collected in the pre-evacuated preliminary vacuum chamber 85, and replaced with a film compensating plate suitable for a new situation. The vacuum processing chamber 11 is introduced by the rollers 13. By doing so, without exposing the vacuum processing chamber 11 to the atmosphere,
The thickness correction plates 87 and 89 can be exchanged.

FIG. 8 is a flowchart showing a specific sequence. When replacing the film thickness compensating plates 87 and 89, the film forming operation in the vacuum processing chamber 11 is temporarily stopped, the gate valve 15 is opened, and the film thickness compensating plates 87 are preliminarily evacuated to the preliminary vacuum chamber 85. , 89 are transferred. Then, it is confirmed by the position sensors 93 and 93 that the film thickness correction plates 87 and 89 have been completely transferred to the preliminary vacuum chamber 85 (see FIG. 5), and the gate valve 15 is closed.
To the atmosphere. Next, new film thickness correction plates 87, 8
After the vacuum chamber 9 is evacuated, the gate valve 15 is opened, and new film thickness compensating plates 87 and 89 are transferred into the vacuum processing chamber 11. And
After the film thickness compensating plates 87 and 89 are disposed at predetermined positions in the vacuum processing chamber 11 by the position sensors 91 and 91, the gate valve 15 is closed and the film forming process is restarted. In this manner, film formation can be performed continuously while maintaining uniform film thickness without exposing the vacuum processing chamber 11 to the atmosphere.

[0019]

According to the present invention, a thin film such as an antireflection film can be formed on both surfaces of a spectacle lens without requiring a complicated reversing mechanism.

[Brief description of the drawings]

FIG. 1 is a longitudinal section showing an embodiment of an apparatus used in the present invention.

FIG. 2 is a cross-sectional view (plan view) taken along line AA of FIG.

FIG. 3 is an explanatory perspective view showing a positional relationship between a substrate holder, a target, and an inductively coupled plasma generator.

FIG. 4 is an explanatory view showing a rotation mechanism of a substrate holder.

FIG. 5 is an explanatory view showing a transport mechanism of a substrate holder and a film thickness correction plate.

FIGS. 6A and 6B are layout views showing the arrangement of magnets on the back surface of the target, where FIG. 6A is a plan view and FIG. 6B is a cross-sectional view taken along line BB of FIG.

FIG. 7 is an explanatory perspective view illustrating a positional relationship among a target, a substrate holder, and a film thickness correction plate.

FIG. 8 is a flowchart showing a sequence of a replacement operation of a film thickness correction plate.

[Explanation of symbols]

 Reference Signs List 11 vacuum processing chamber 13 transport rollers 15, 17 gate valve 21 rotation mechanism 23 upper support member 25 lower support member 27 chucking projection 29 motor 31 substrate holder 33 eyeglass lens (substrate) 41 sputter electrode 42 yoke 43 target 44 magnet (S Pole) 45 Sputter power supply 46 Magnet (N pole) 47 Mass flow 49 Sputter gas cylinder 51 Shielding plate 61 Inductively coupled plasma generator 63 High frequency (RF) discharge chamber 65 High frequency (RF) coil 66 Internal magnetic field coil 67 Matching box 69 High frequency (RF) ) Power supply 71 Shielding plate 73 Mass flow 75 Reactive gas cylinder 81 Carrier 83 Introducing chamber 85 Preliminary vacuum chamber 87, 89 Film thickness compensating plate 91 Position sensor 93 Position sensor

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hajime Kamiya 2-7-5 Nakaochiai, Shinjuku-ku, Tokyo Inside Hoya Corporation (72) Inventor Shigeharu Matsumoto 3-2-6 Minamioi, Shinagawa-ku, Tokyo Inside Syncron Co., Ltd. (72) Inventor Kazuo Kikuchi 3-2-6 Minamioi, Shinagawa-ku, Tokyo Inside Syncron Co., Ltd.

Claims (12)

[Claims] 1. A method for simultaneously forming a film on both surfaces of a spectacle lens by sputtering, wherein the spectacle lens is mounted on a flat substrate holder and introduced into a vacuum processing chamber. A double-sided simultaneous film forming method, wherein a metal compound thin film having a desired thickness is simultaneously formed on both sides of an eyeglass lens by repeating i) a sputtering step and (ii) a converting step. (I) A sputtering process in which a target is sputtered on the spectacle lens using a sputtering device provided on both sides of the spectacle lens, and a metal-based ultrathin film made of a metal or an incompletely reacted metal is formed on each side of the spectacle lens. (Ii) a conversion step of reacting a metal-based ultrathin film with a reactive gas to convert it into a metal compound ultrathin film 2. The double-sided simultaneous film forming method according to claim 1, wherein the conversion step is performed by exposing the substrate to a reactive gas plasma. 3. The double-sided simultaneous film forming method according to claim 1, wherein the conversion step is performed by irradiating an ion beam of a reactive gas. 4. A substantially trapezoidal or fan-shaped target in which the substrate holder is formed in a disk shape and is rotated in a horizontal direction in a vacuum processing chamber with its center as an axis, so that the area increases from the center of the substrate holder toward the outer peripheral portion. 2. The simultaneous double-sided film forming method according to claim 1, wherein the film thickness distribution of the thin film formed on the spectacle lens is made uniform by sputtering. 5. The simultaneous double-sided film formation according to claim 1, wherein a shielding plate for controlling the gas partial pressures of the sputtering step and the conversion step for each atmosphere is provided in the vacuum processing chamber to perform the sputtering step and the conversion step. Method. 6. A thin film formed on a spectacle lens between a spectacle lens mounted on the substrate holder and a target, wherein the substrate holder is formed in a disc shape and is rotated in a horizontal direction about a center thereof in a vacuum processing chamber. A film thickness compensating plate is provided as a masking member to make the film thickness distribution uniform, and a preliminary vacuum chamber connected to the vacuum processing chamber and capable of communicating with the vacuum processing chamber without exposing the vacuum processing chamber to the atmosphere. Is established,
2. The double-sided simultaneous film forming method according to claim 1, wherein the film thickness correction plate is exchanged between the preliminary vacuum chamber and the vacuum processing chamber. 7. An apparatus for simultaneously forming a film on both surfaces of a spectacle lens by sputtering, comprising: a vacuum processing chamber; and a disk-shaped apparatus which is disposed in the vacuum processing chamber and has a spectacle lens mounted thereon and rotates in a horizontal direction. A substrate holder, comprising a sputtering device and a reactive gas supply source respectively provided on both surface sides of the substrate holder, and rotating the substrate holder to move the spectacle lens between the sputter source and the reactive gas supply source. It is alternately and repeatedly conveyed, and a metal-based ultrathin film made of a metal or an incomplete reactant of metal is formed on both surfaces of the spectacle lens by sputtering with a sputtering device. By reacting with the reactive gas and converting it to an ultrathin metal compound, the substrate holder is rotated to form the ultrathin metal-based film and convert the metal compound to an ultrathin film. A double-sided simultaneous film forming apparatus characterized in that a thin film having a desired film thickness is formed by turning back. 8. The simultaneous double-sided film forming apparatus according to claim 7, wherein a plasma source is used as the reactive gas supply source. 9. The double-sided simultaneous film forming apparatus according to claim 7, wherein an ion beam generating source is used as the reactive gas supply source. 10. The double-sided simultaneous film forming apparatus according to claim 7, wherein the turret of the sputtering apparatus is a trapezoidal or fan-shaped target whose area increases from the center of the opposing substrate holder toward the outer peripheral portion. 11. A shielding plate is provided between the sputter source and the reactive gas supply source, and the partial pressure of the sputter gas in the sputter source and the gas partial pressure during the reaction and conversion by the reactive gas supply source are individually set. The double-sided simultaneous film forming apparatus according to claim 7, wherein the control is performed in the following manner. 12. Further, the vacuum processing chamber is connected to the vacuum processing chamber,
A preparatory vacuum chamber capable of communicating without exposing the vacuum processing chamber to the atmosphere; provided between the substrate holder and the casing, as a masking member for uniforming the film thickness distribution of the thin film formed on the spectacle lens. A film thickness correction plate; and a transfer means for transferring the film thickness correction plate between the vacuum processing chamber and the preliminary vacuum chamber; enabling replacement of the film thickness correction plate without exposing the vacuum processing chamber to the atmosphere. The double-sided simultaneous film forming apparatus according to claim 7.