JPH1046340A - Film forming method and film forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film-forming method and a film-forming apparatus by sputtering or the like in which a film boundary is not generated at the time of forming a film on a surface of a donut-shaped disc-shaped substrate such as a CD. With the goal. SOLUTION: In a film forming method in which a metal material is scattered on a surface of a donut-shaped disk-shaped substrate 11 in a chamber 51 connected to a decompression device to form a donut-shaped metal film 2, a central portion 13 of the disk-shaped substrate 11 is provided. And a film forming method and a film forming apparatus for applying a film material by pressing and holding the peripheral portion 14 from both sides.

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 forming a film of aluminum or the like on the surface of a donut-shaped disk-shaped substrate such as a compact disk by sputtering or the like.

[0002]

2. Description of the Related Art Recently, compact discs (hereinafter referred to as CDs) and digital video discs (hereinafter referred to as DVDs) which are widely used for recording a large amount of digitized audio signals and image information. ) Is formed by forming a thin film of aluminum or the like having a high light reflectivity on a surface of a donut-shaped disk-shaped base made of a transparent synthetic resin plate such as polycarbonate by sputtering or the like.

In a CD, for example, a small hole called a bit in which information is converted into a digital signal consisting of "1" and "0" is formed in a film of aluminum or the like on the surface of the substrate and recorded. The recorded information is read out by detecting the presence or absence of a reflected wave (the presence or absence of a hole) by applying a laser beam.

As shown in FIG. 4, the current 12 cm CD1 has a disc-shaped base 11 having an outer diameter of 120 mm, a thickness of 1.2 mm, a central hole 12 having a diameter of 15 mm, and a transparent portion formed of the base 11. Between about 20 mm from the center, the coating 2 of aluminum or the like is about 20 mm to about 59 mm from the center of the base 11.
Inner side 13 and outer end side (peripheral portion) 14 around hole 12
Are formed during the removal.

Conventionally, a film is formed on the surface of this toroidal disk-shaped substrate by, for example, sputtering, as shown in FIG.
The equipment was used as shown in the figure. If the disk-shaped substrate 11 placed and transferred on the stepped portion 63 of the holder 64 in a vacuum chamber such as a chamber is sputtered in this state, the coating 2 is formed on the entire surface, so that masking is performed. Work is being done.

That is, a center bracket 81 is disposed inside the holder 64 so as to be able to freely advance and retreat. The center bracket 81 is elastically attached to the distal end of the shaft 83 via a coil spring 85 with a degree of freedom in the axial direction, and the distal end is easily inserted into the hole of the donut-shaped disk-shaped base 11. A tapered head portion 87 is formed in such a manner. A cylinder device 84 is connected to a lower end of the shaft 83. Further, a magnetron sputtering device (not shown) serving as a sputtering source, a center mask 71 having a circular tip and an outer mask 73 having a ring shape are provided above.

[0007] In the sputtering operation, when the cylinder device 84 is operated to raise the shaft 83, the leading portion 87 at the tip of the center bracket 81 enters the center hole 12 of the disk-shaped base 11. Since this head portion 87 is tapered, it easily penetrates into the center hole 12 and the
When 1 reaches the flat portion, the disk-shaped base 11 is pushed up from the step 63 of the holder 64. When the disc is further pushed up, the center of the disc-shaped base 11 is moved to the center mask 7.
The peripheral portion 14 of the disc-shaped base 11 also contacts the contact portion 74 of the outer mask 73 as well as the contact portion 72. At this time, the disk-shaped base 11 is elastically deformed, and the peripheral portion 14 of the disk-shaped base 11 is reliably pressed against the outer mask 73 by the reaction force.

In this state, when the inside of the chamber reaches a predetermined degree of vacuum, the magnetron sputtering device is operated to discharge aluminum fine particles, and the disk-shaped substrate 11
An aluminum coating 2 is formed on the surface of. When the formation of the coating 2 is completed, when the cylinder device 84 is operated to lower the shaft 83, the inner bracket 81 holding the disk-shaped base 11 is lowered and the holder 64 in the middle is lowered.
When passing through the portion, the peripheral portion 14 of the disc-shaped base 11
, The disc-shaped base 11 is placed on the step 63.

Thereafter, the work is completed by filling the chamber with nitrogen or the like and taking out the disk-shaped substrate 11 from the holder 64.

However, in the sputtering operation using such an apparatus, the formed coating film 2 may have defects. This depends on the type, material, thickness, and the like of the disc-shaped base 11, and there is also variation in the same part.
Outer mask 7 applied to peripheral portion 14 of disk-shaped base 11
Since the stress applied to the disk-shaped substrate 11 also changes depending on the pressing force of No. 3 and the applied coating material, a gap is formed between the disk-shaped substrate 11 and the center mask 71 or the outer mask 73, and the coating material enters. There was something. (Note that FIG. 5 is an exaggerated view of the deformed state of the disk-shaped substrate 11.) When the coating is applied to the non-formed portion, the boundary is unclear, and the coating may be blurred. There was a need for improvement in both characteristics and appearance. Further, the outer edge portion 14 is rubbed when the disk-shaped substrate 11 bends, for example, due to warping, and returns to the original state, so that there is a flaw near the outer edge portion 14.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and when forming a film on the surface of a donut-shaped disk-shaped substrate such as a CD, there is no occurrence of blurring or the like at the boundary of the film. It is an object to provide a film forming method and a film forming apparatus by sputtering or the like.

[0012]

According to a first aspect of the present invention, there is provided a film forming method, wherein a coating material is scattered on the surface of a donut-shaped disk-shaped substrate in a chamber connected to a decompression device to form a donut-shaped coating. In the method of forming a film, the central portion and the peripheral portion of the disk-shaped substrate are pressed and held from both front and back surfaces to apply the coating material.

[0013] Since the film is formed in a state where the center portion and the peripheral portion of the disc-shaped substrate are held substantially straight from both the front and back surfaces, the boundary of the film formation can be clearly defined. Further, since no deformation such as warpage occurs in the disk-shaped base, the peripheral edge of the base does not shift and no abrasion occurs.

According to a second aspect of the present invention, there is provided a film forming method comprising: a step of holding a peripheral portion of a donut-shaped disc-shaped base in a holder in a chamber connected to a decompression device; and a center bracket raised in the holder. Is inserted into the hole of the donut-shaped disc-shaped base, and the disc-shaped base is placed on the center bracket, and the outer bracket provided on the shaft of the center bracket abuts on the periphery of the disc-shaped base. Raising the bracket, raising the bracket to contact the center portion of the upper surface of the donut-shaped disc-shaped base with the center mask, and contacting the peripheral portion with the outer mask, and scattering the coating material in the evacuated chamber. A step of forming a coating on the upper surface of the donut-shaped disk-shaped substrate, and lowering both brackets to remove the upper surface of the donut-shaped disk-shaped substrate. Removing the donut from the disc, further lowering the two brackets, separating the donut-shaped disc-shaped base from the bracket and mounting the donut-shaped disc-shaped base on the holder, and removing the donut-shaped disc-shaped base placed on the holder. It is characterized by having.

An operation similar to that of the first aspect is achieved.

According to a third aspect of the present invention, there is provided a film forming apparatus comprising: a chamber connected to a decompression device; a holder provided in the chamber for holding a donut-shaped disk-shaped substrate;
A center bracket which is inserted into the holder so as to be able to advance and retreat and whose tip is inserted into a hole of the donut-shaped disc-shaped base and which holds the disc-shaped base, and a donut-shaped disc type provided on a shaft of the center bracket An outer bracket that abuts an edge of the base, a spring member that elastically supports the center bracket and the outer bracket on the shaft, and a center part of a donut-shaped disk-shaped base provided corresponding to the center bracket. A center mask for covering, an outer mask for covering a peripheral portion of the donut-shaped disk-shaped base provided corresponding to the outer bracket, and a device for scattering a coating material provided on the side where the center mask and the outer mask are provided. It is characterized by having.

According to the first aspect of the present invention, the same operation as described above is achieved.

According to a fourth aspect of the present invention, there is provided the film forming apparatus, wherein the inner peripheral diameter of the holder is larger than the outer diameter of the donut-shaped disk-shaped base, and a plurality of protruding convex portions are formed on the inner peripheral edge. The outer diameter of the outer bracket is larger than the outer diameter of the donut-shaped disk-shaped base, and a plurality of concave portions are formed in the peripheral portion, so that the concave and convex portions of the two coincide and can be inserted without contacting each other. .

The holder and the outer bracket whose center is provided coaxially can be interchanged without contact or collision while holding the disc-shaped base.

A film forming apparatus according to a fifth aspect of the present invention is characterized in that the center bracket and the outer bracket each include a spring member that acts independently.

[0021] Both brackets having their centers provided coaxially,
The spring member expands and contracts even if the thickness and the like of the disk-shaped base vary or the product type changes and the thickness differs, and the disk-shaped base can be held substantially in a straight line. It has the same function as.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an example of a film forming apparatus by sputtering which is a manufacturing process of a CD, and FIG. 2 is an enlarged front sectional view showing a main part of FIG.

In FIG. 1, reference numeral 3 denotes a belt conveyor for placing and transporting the donut-shaped disk-shaped substrate 11 of the CD 1, and 4 denotes a transfer device, which is a rotating shaft 41 which can move up and down (arrows).
Disc-shaped brackets 42 and 42 are mounted on the lower surface of each of the brackets 42 and 42, which cover window holes 52 of a chamber 51, which will be described later. (Not shown) are provided. In addition, the tip portions of the rubber pads 43, 43
It is preferable to be located on the inner end side 13 where the coating 2 is not formed on the outer periphery than the center hole 12 because the coating 2 is not damaged.

A sputtering apparatus 5 includes a chamber 51 provided with circular window holes 52, 53 having a diameter larger than that of the donut-shaped disk-shaped base 11 for sputtering. A rotating shaft 61 is provided in the chamber 51. Brackets 62, 62 extending in relative directions at the center are attached, and each bracket 62, 62 has a ring-shaped holder 6 having a stepped portion 63 on which the peripheral portion 14 of the disk-shaped base 11 is placed and held.
4,64 are provided. Reference numeral 54 denotes a film forming chamber connected to the window hole 53 for performing sputtering, and the chamber 51 and the film forming chamber 54 constitute a vacuum chamber.

In the film forming chamber 54, a center mask 71 for covering the center of the magnetron sputtering apparatus 7 and the disk-shaped substrate 11 is provided. Reference numeral 72 denotes a contact portion of the tip of the center mask 71 with the vicinity of the center hole 12 of the disc-shaped base 11. Reference numeral 73 denotes an outer mask provided on the inner periphery of the window hole 53, reference numeral 74 denotes a contact portion with the peripheral portion 14 of the disk-shaped base 11, and reference numeral 55 denotes a decompression device (not shown) such as a vacuum pump. The black spots in the exhaust passage 95 and the like are packing for maintaining airtightness.

Reference numeral 8 denotes a pusher, which is inserted through the center hole 12 of the donut-shaped disc-shaped base 11 and places the center bracket 81 holding the disc-shaped base 11 and the peripheral portion 14 of the disc-shaped base 11. An outer bracket 82 is fixed to the shaft 83. A cylinder device 84 for moving the shaft 83 up and down by electromagnetic operation or gas pressure operation is hermetically attached to the bottom wall of the chamber 51 below the film forming chamber 54. The shaft 83 does not rotate.

Further, a part constituting a main part of the present invention will be further described with reference to FIGS. In FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

A center bracket 8 fixed to the tip of a shaft 83 connected to the cylinder device 84 with a screw or the like.
The outer bracket 82 on the rear side, which is fixed to the first and middle portions with a stopper 88a, has coil-shaped spring members 85 and 86 fitted to the shaft 83, respectively, and has elastic flexibility in the axial direction. It is attached. FIG.
Reference numeral 87 denotes a tapered leading portion of the center bracket 81, 88 b denotes a stopper of the coil spring 86 of the outer bracket 82, and 89 denotes a contact portion of the tip of the outer bracket 82 with the peripheral portion 14 of the disk-shaped base 11. .

FIG. 3A is a top view of a holder 64 in which the holding portion of the donut-shaped disk-shaped base 11 has a ring shape. The inner diameter of the holder 64 is larger than the outer diameter of the disk-shaped base 11. A plurality of projecting steps 63, 63, ... are formed on the inner peripheral edge. FIG. 3B is a top view of the outer bracket 82, the outer diameter of which is a disc-shaped base 1.
1 and a plurality of recesses 90, 9 on the peripheral edge.
0,... Are formed. Then, the relationship between the two is a double state in which the outer bracket 82 is inserted inside the holder 64, but the outer peripheral portions of the outer portions 82 and the concave and convex portions 65 and 90 match each other, so that the gap can be inserted without contacting each other.

The sputtering operation in the sputtering apparatus 5 is performed as follows.

The donut-shaped disk-shaped substrate 11 conveyed by the belt conveyor 3 is sucked by the rubber pads 43 provided on the disk-shaped bracket 42 of the transfer device 4 which has been lowered. (A depressurizing device such as a vacuum pump is not shown.) Then, the rotating shaft 41 of the transfer device 4 is raised, and for example, when the rotating shaft 41 comes to a position indicated by a virtual line in FIG.
Is rotated by 180 degrees, and then the rotating shaft 41 is lowered to move the disk-shaped bracket 42 onto the circular window hole 52 of the chamber 51 of the sputtering apparatus 5. In this state, the disc-shaped bracket 42 is
Is closed, and the disk-shaped base 11 is positioned on the ring-shaped holder 64 in the chamber 51. Then, when the suction of the rubber pads 43, 43 is released (nitrogen or the like is sealed in the suction line), the disc-shaped base 11 is
4 is placed on the step 63.

Next, the rotating shaft 61 in the chamber 51 is rotated by 180 degrees, and the holder 6 on which the disc-shaped base 11 is placed is placed.
4 is moved to a position facing the film forming chamber 54. After the circular window 52 is closed by the bracket 42, the inside of the chamber 51 and the inside of the film forming chamber 54 are exhausted through an exhaust passage 55 to reduce the pressure. Next, when the shaft device 83 is moved up by operating the cylinder device 84, the tapered head portion 87 of the center bracket 81 at the tip of the shaft 83 makes the hole 1 at the center portion of the donut-shaped disk-shaped base 11 on the holder 64.
2 and the outer bracket 82 on the rear side also rises, and the abutting portion 89 at the front end is
And the brackets 81 and 82 cooperate to push up the disc-shaped base 11 from above the holder 64.

The disc-shaped base 11 pushed up and held by the brackets 81 and 82 in contact with the center hole 12 and the peripheral edge portion 14 has a contact portion 72 of a center mask 71 having a central portion on the opposite surface located above. And the periphery 1
4 is pressed against the contact portion 74 of the outer mask 73. That is, the disc-shaped base 11 is held in a horizontal state without being curved by the central portion and the peripheral portion 14 being pinched and pressed from both side surfaces. At this time, both brackets 81, 82
Are provided via independent spring members 85 and 86, respectively, so that the respective pressing forces can be absorbed and held horizontally.

When the exhaust in the chamber 51 and the film forming chamber 54 reaches a predetermined degree of vacuum in this state, the magnetron sputtering device 7 is operated to sputter aluminum as a coating material. The aluminum particles scattered by this sputtering are mainly
1, the outer surface of the center mask 71 and the surface of the outer mask 73, and an aluminum film 2 having a predetermined thickness can be formed thereon.

When the sputtering is completed, the cylinder device 84 is operated to lower the shaft 83, and the inner bracket 81 and the outer bracket 82 holding the disk-shaped base 11 are also lowered, and pass through the holder 64 partway. At this time, the peripheral portion 14 of the disc-shaped base 11 is hooked on the step 63, and the disc-shaped base 11 is placed on the step 63.

Then, the rotation shaft 61 is rotated by 180 degrees,
The holder 64 on which the disk-shaped base 11 is placed is moved rightward in FIG. 1, the exhaust is stopped, and nitrogen or the like is sealed in the chamber 51 through the exhaust passage 55. When the inside of the chamber 51 reaches the atmospheric pressure state, the rubber pad 43 of the bracket 42 on the circular window hole 52 of the chamber 51,
43 is connected to a vacuum system, and the disk-shaped substrate 11 on the holder 64 is sucked.

Next, the rotating shaft 4 of the transfer device 4
1 and, for example, when it reaches the position indicated by the imaginary line in FIG. 1, the rotation shaft 41 is rotated by 180 degrees.
When the vacuum state of 43 is changed to the atmospheric pressure, the holding of the disc-shaped base 11 is released, and the disc-shaped base 11 on which the aluminum coating 2 is formed can be taken out.

After that, the transfer device 4 is lowered, a new disk-shaped substrate 11 on the conveyor 3 is sucked by the rubber pads 43, 43, sent to the sputtering device 5, and the above-described operation is repeated.

The doughnut-shaped disk-shaped substrate 11, which has been sputtered by the above-described apparatus and method, has its central portion and its peripheral portion 14 sandwiched and pressed by masks 71, 72, etc., from both side surfaces, so that it is curved, such as warped. Sputtering is performed in a state where the coating 2 is formed in a horizontal state, and the boundary of the formation of the coating 2 becomes clear.
CD1 with improved characteristics and appearance could be produced.

The CD 1 shown in FIG. 4 in which the aluminum coating 2 is formed using the center bracket 81, the outer bracket 82, the center mask 71 and the outer mask 73 shown in FIG.
m, the width W of the non-coated portion from the end face of the peripheral portion 14 is 1 mm
The boundary was clear and no blurring or the like was observed in the coating 2.

The present invention is not limited to the above embodiment. For example, the object of film formation is not limited to CD,
(Laser disk), DVD (digital video disk), MD (mini disk), MO (magnet optical), and the like.

In the above embodiment, the case where the film is formed by sputtering has been described. However, the present invention is not limited to sputtering, and a method and apparatus by vacuum deposition or ion plating for forming a film in a vacuum can be applied. . In addition, the detailed configuration of each unit of the apparatus is not limited to that described in the embodiment. In addition, the work was performed from above by holding the disc-shaped base horizontally, but may be performed not only from above but also from below, and further, by holding the disc-shaped base vertically and forming the coating. Is also good.

Further, the coating material is aluminum (Al).
In addition, a film of gold (Au), silver (Ag), copper (Cu), silicon (Si), or the like can be formed.

[0044]

According to the first to third aspects of the present invention, the disk-shaped substrate can be held straight at the center and the outer end, and a uniform coating can be formed in a predetermined range with high accuracy. In addition, since the base is held elastically, it can be held straight even if the thickness of the base or the film-forming material changes, and there is no abrasion that occurs when the disk-shaped base curves or returns from the curve. Occurrence can be prevented.

According to the invention of claim 4 of the present invention,
The transfer of the disk-shaped substrate can be easily performed with a simple configuration.

Further, according to the fifth aspect of the present invention, the straightness of the disk-shaped base can be increased with a simple structure, and the cost of the apparatus can be reduced.

Further, according to the invention of claim 6 of the present invention, a CD (substrate thickness 1.2 mm) or a DVD (substrate thickness 0.6 mm) can be used without switching the apparatus. It can be easily performed with a simple adjustment.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of a sputtering apparatus of the present invention.

FIG. 2 is an enlarged partial cross-sectional front view showing a main part of the present invention.

FIG. 3 is an explanatory view of a main part of the present invention as viewed from above, and FIG.
Indicates a holder, and (b) indicates an outer mask.

FIG. 4 is a front view of a compact disc (CD).

FIG. 5 is a partially sectional front view showing a part of a conventional sputtering apparatus.

[Explanation of symbols]

 1: compact disk (CD) 11: donut-shaped disc-shaped substrate 12: center hole 14: peripheral portion 2: coating film 5: sputtering device 51: chamber 54: film forming chamber 63: step portion 64: holder 71: center mask 73 ： Outer mask 81 ： Center bracket 83 ： Shaft 84 ： Cylinder device

Claims (5)

[Claims] 1. A film forming method for forming a donut-shaped film by scattering a film material on the surface of a donut-shaped disk-shaped substrate in a chamber connected to a decompression device, wherein a center portion and a peripheral portion of the disk-shaped substrate are front and back. A film forming method, wherein a film material is applied by pressing and holding from both sides. 2. A step of holding a peripheral portion of the donut-shaped disc-shaped base by a holder in a chamber connected to the pressure reducing device; and a step of moving the tip of the center bracket raised inside the holder into a hole of the donut-shaped disc-shaped base. And placing the disc-shaped base on the center bracket, and contacting the outer bracket provided on the shaft of the center bracket with the periphery of the disc-shaped base; raising the bracket to a donut shape Contacting the center of the upper surface of the disk-shaped substrate with the center mask and the peripheral portion of the disk-shaped substrate against the outer mask; and forming a coating on the upper surface of the donut-shaped disk-shaped substrate by scattering the coating material in the evacuated chamber. Lowering the two brackets to remove the upper surface of the donut-shaped disc-shaped base from the mask; A step of moving the donut-shaped disk-shaped base body down from the bracket by lowering the bracket and mounting the same on a holder; and a step of taking out the donut-shaped disk-shaped base body mounted on the holder. Film forming method. 3. A chamber connected to a decompression device; a holder provided in the chamber for holding a donut-shaped disc-shaped base; and a tip of a donut-shaped disc-shaped base inserted into the holder so as to be able to advance and retreat. A center bracket inserted into the hole and holding the disc-shaped base;
An outer bracket provided on a shaft of the center bracket and in contact with an edge of a donut-shaped disc-shaped base; a spring member for elastically supporting the center bracket and the outer bracket on the shaft; A center mask that covers a central portion of the donut-shaped disk-shaped substrate provided as described above; an outer mask that covers a peripheral portion of the donut-shaped disk-shaped substrate provided corresponding to the outer bracket; and the center mask and the outer mask. And a device provided on the disposition side for scattering the coating material. 4. The inner diameter of the holder is larger than the outer diameter of the donut-shaped disk-shaped base, a plurality of protruding protrusions are formed on the inner peripheral edge, and the outer diameter of the outer bracket is a donut-shaped disk. 4. The film forming apparatus according to claim 3, wherein a plurality of recesses are formed in a peripheral portion of the substrate, the recesses being larger than an outer diameter of the base, and the two concave and convex portions can be inserted without contacting each other. 5. The film forming apparatus according to claim 3, wherein each of the center bracket and the outer bracket includes a spring member that operates independently.