Patent Application
20080029023
The present invention relates to a vacuum processing device depositing continuously a multilayer film on a substrate of such an optical disk or an optical component.
Optical disks such as the compact disk (CD) or the digital versatile disk (DVD) have been diversified recently, and therefore availability thereof has been still growing from an information medium of reading-only to an optical information medium capable of writing. Synthetic resin, typically polycarbonate, having a low mold shrinkage ratio or a low expansion coefficient is used for substrate materials of the optical disk. Information is recorded on the surface of the substrate as a pit row in the case of the read-only disk, and a guide groove to become the track for laser is formed on the surface of the substrate in the case of the disk capable of writing. A multilayer film containing a writing layer is deposited on the surface to constitute the disk.
Because quantity of information to be recorded on a disk increases, a structure of the film that enables sure read has been required for densification of recorded information and acceleration of reading speed (Patent Document 1). In order to respond such requirement, it is necessary that the device forming the film should be much more improved on the performance thereof, for example, increasing the number of layers of the multilayer film, or regulating precisely the thickness of the layer.
For example,
In a general vacuum processing device, a disk substrate of the object to be processed is carried on the rotary table disposed in the chamber, and is transported to the film-depositing chambers disposed on a circumference with an interval for overlapped film-depositing. Because the number of the film-depositing chambers is increased as the number of layers in the multilayer film increases, the radius of the circumference becomes large. As a result, the dimension of the chamber containing the carrying table is enlarged. Therefore, because the volume to be evacuated increases remarkably, the volume of the exhaust system evacuating to a vacuum state must be increased to the extent beyond necessity, and enlarged. Additionally, carrying circumference for the processed object on the rotary table becomes large, so that the centrifugal force subject to the processed object cannot be neglected when the table is rotated with a high speed to shorten the tact time. Furthermore, intermittent drive control of the rotary table becomes complicated.
Patent Document 1: Japanese Patent Laid-open No. 2001-209974
As to conventional vacuum processing devices, if an attempt to increase the number of film-depositing chambers is made in an device where a series of film-depositing processes are carried out by carrying intermittently with horizontal rotation in an evacuated carrying space, the device must result in a large sized one. In the case that a multilayer film-deposited by a small number of film-depositing is fabricated to cope with various film structures, useless processing chambers would be generated. Though it may be thought that film-depositing is executed with setting a plurality of processing devices in line, there is a problem that obtaining steadily the quality of products should be difficult because processed objects must be taken out from the vacuum space into the atmosphere while the objects are being processed.
The present invention is intended to obtain a vacuum processing device capable of corresponding to a wide variety of production processes, which can layer efficiently many kinds and thicknesses of films with high reliability and downsize the manufacturing device by suppressing the device become large-sized due to increase of the number of film-depositing chambers according to increase and complication of processing steps.
According to an embodiment of the present invention, an aspect of the present invention is a vacuum processing device comprising:
a first film-depositing process part comprising, a first chamber being evacuated in a vacuum state, a first rotary carrying table disposed in the first chamber and having a plurality of susceptors carrying a processed object at a predetermined angular interval so as to form a carrying route for the processed object, and a plurality of film-depositing chambers disposed along a circumference centered at a rotating shaft of the rotary carrying table in the first chamber and depositing a film in a multilayered form on the processed object to be carried by the rotary carrying table;
a second film-depositing process part comprising, a second chamber being evacuated in a vacuum state, a second rotary carrying table disposed in the second chamber and having a plurality of susceptors carrying a processed object at a predetermined angular interval so as to form a carrying route for the processed object, and at least one film-depositing chamber disposed along a circumference centered at a rotating shaft of the second rotary carrying table in the second chamber and depositing a film on the processed object to be carried by the second rotary carrying table;
a connecting part connecting the first film-depositing process part with the second film-depositing process part, and delivering the processed object processed in the first and the second film-depositing process parts to each other; and
a load lock mechanism disposed on any one of the first film-depositing process part, the second film-depositing process part and the connecting part and carrying the processed object in or out of the chamber while maintaining a vacuum state.
Moreover, the number of the first film-depositing chambers can be different from the number of the second film-depositing chambers.
Additionally, a sequence of processing steps can be performed upon connecting the two film-depositing process parts together, or the same processing can be executed in parallel by the two film-depositing process parts in compliance with the number of the film-depositing processing chambers.
Furthermore, the first film-depositing process part and the second film-depositing process part can be provided with a cooling chamber cooling the processed object between respective film-depositing chambers.
Besides, the vacuum processing device is able to include an operation control part to control the device, wherein the load lock mechanism is arranged in the first film-depositing process part, and a film is deposited on the processed object carried from the load lock mechanism into the first chamber arranged in the first film-depositing process part after the object is carried by the first rotary table, the object being transported to the connecting part and then a film being deposited on the object in the second film-depositing chamber after the object being transported thereto by the second rotary table of the second chamber of the second film-depositing process part from the connecting part, the processed object having the films deposited thereon being transported to the first rotary table via the connecting part and a film being deposited thereon in the first film-depositing chamber, thereafter the object being taken out from the load lock mechanism.
The load lock mechanism is arranged in the connecting part and the connecting part contains a delivering mechanism for the processed object capable of doubling as the load lock mechanism.
The connecting part includes positions delivering the processed object to the first film-depositing process part and the second film-depositing process part, and at least one of the delivering positions can double as a cooling chamber. Furthermore, a third film-depositing process part is connected with at least one of the first film-depositing process part and the second film-depositing process part, wherein the third film-depositing process part is comprised of a third chamber capable of being evacuated in a vacuum state, a third rotary carrying table disposed in the third chamber and having a plurality of susceptors carrying a processed object at a predetermined angular interval so as to form a carrying route for the processed object, and a third film-depositing chamber disposed along a circumference centered at a rotating shaft of the rotary carrying table in the third chamber and depositing a film on the processed object to be carried by the rotary carrying table.
The present invention can effectively layer various kinds and thicknesses of films with high reliability. In addition, the present invention can aim to downsize a manufacturing device by suppressing enlargement of the size of the device due to increase of the number of film-depositing chambers caused by increase and complexity of process stages. Thereby, a vacuum processing device capable of responding to various production processes can be obtained.
In the present invention, ‘vacuum’ means a state that is depressurized to a pressure lower than the atmosphere, and ‘vacuum processing’ means carrying out a process such as film-depositing by sputtering under a reduced pressure.
Referring to the drawings, some embodiments of the present invention will be explained hereinafter. An aspect of the present invention is a vacuum processing device where a plurality of film-depositing process parts having a carrying table and a film-depositing chamber are connected together in a chamber capable of being evacuated in a vacuum state, and a processed object is transported to the film-depositing process parts to form a film thereon in a multilayer with a continuous processing. Detailed explanation thereof will be executed with the embodiments.
In the first film-depositing process part 10, four film-depositing chambers 12a, 12b, 12c and 12d are disposed on a circumference c1 with a predetermined radius r1 centered at the vicinity of the center of the first chamber 11 in such a manner that the centers thereof are positioned on the circumference. Four spaces between respective film-depositing chambers are defined as ‘space positions’. A cooling chamber 13a is arranged between the film-depositing chamber 12a and the film-depositing chamber 12b, and a cooling chamber 13b is arranged between the film-depositing chamber 12c and the film-depositing chamber 12d. In addition, a load lock mechanism 14 is disposed between the film-depositing chamber 12d and the film-depositing chamber 12a, and a first delivering position 31 of the connecting part 30 is arranged between the film-depositing chamber 12 band the film-depositing chamber 12c. A load lock chamber 14a of the load lock mechanism and the first delivering position 31 are arranged so that they can be positioned oppositely to each other with respect to the center of the first chamber 11 and on the line dividing the main chamber 1 symmetrically into upper and lower portions in the figure. The load lock chamber 14a can double as a cooling chamber.
As shown in
The susceptor 16 is mounted on a susceptor-receiving hole 15b disposed along the circumference of a table plate 15a of the rotary carrying table 15 so as to be movable vertically. To the bottom portion 2 of the chamber corresponding to each position of the first chamber, a susceptor push-up mechanism called ‘pusher 17’ is fixed. When a pusher piston 17a is driven upward as illustrated by the arrow in the figure, the susceptor 16 arrived at this position is pushed up and closes tightly the openings of the film-depositing chamber 12b or the load lock chamber 14a in
In the case of operation by actual devices, all of eight susceptors including cooling chamber positions are pushed up simultaneously with synchronization by the pushers. With finishing of task, the pushers descend and the susceptors 16 return to the table plate 15a by the aid of a spring 16c. The table turns intermittently by 45 degrees to move the susceptor to the next position. The pusher is driven again at the next position and processing is carried out.
Evacuation of the chamber is carried out by an external exhaust pump (not shown) connected to an exhausting passage 15d formed in a rotating shaft 15c of the rotary carrying table.
As shown in
The film-depositing chamber 12 (12a to 12d) deposits coated films on the transported disk substrate by sputtering. Sputtering is carried out by a glow discharge generated in the film-depositing chamber upon applying a direct or alternate voltage between the electrode of the target 12, side and the electrode located in the vicinity of the substrate side, in order that a fine target material can be scattered out by impacting the ions generated by the discharge onto the target, and thereby the material is deposited on the disk substrate.
The cooling chamber 13 (13a, 13b) has a structure in which a cooling plate is disposed facing the transported disk substrate and a coolant gas is introduced to cool the substrate by conducting the heat of the disk substrate to the cooling plate side. Cooling in the vacuum is very difficult if the disk substrate is heated and the temperature thereof is raised by the sputtering in the film-depositing chamber of the preceding process. Therefore, upon incorporating a vacuum cooling process between respective film-depositing processes of the continuous vacuum process, film-depositing in the next process can be executed at a desired temperature of the disk substrate.
The load lock mechanism 14 is a mechanism that transports a disk substrate located in the atmosphere into a vacuum chamber without breaking its vacuum state. Load lock upper lids 14c1 and 14c2 are disposed on the both ends of a rotatable pick-and-place-arm 14b to transport the substrate alternately between the load lock chamber 14a and an external conveyor. When the load lock upper lid 14c2, which has conveyed a disk substrate 50 to be processed using an electromagnetic chuck 14d, seals hermetically an outer opening 14a1 of the load lock, the susceptor 16 pushed up by the pusher 17 seals hermetically an inner opening 14a2 of the load lock and receives the disk substrate 50 with masks simultaneously. When the load lock chamber 14a is evacuated by an attached exhaust system (not shown) and the vacuum level thereof comes to reach the extent of the vacuum level in the chamber, the pusher descends and the load lock chamber 14a is opened to the chamber side. Then a disk substrate 50 to be processed is loaded on the rotary carrying substrate 15.
The processed disk substrate 50 on which a multilayer film has been deposited in the final film-depositing chamber 12d is transported to the position of the load lock chamber 14a by the rotary table. When the pusher 17 of this position pushes up the susceptor 16 having the disk substrate 50 loaded thereon and the susceptor is hermetically joined to the inner opening 14a2 of the load lock chamber, the disk substrate with masks is electromagnetically chucked to the upper lid 14c2 simultaneously. When the load lock chamber 14a is leaked up to the atmospheric pressure by the attached exhaust system on the condition above, the upper lid 14c2 is released and lifted by the arm 14b, and then moved to the position of the conveyor. At the same time, the other upper lid 14c1 carries a new disk 50 with masks to be processed to the load lock chamber 14a through the outer opening 14a1, and then the load lock chamber is tightly sealed from the atmosphere. Thereafter, the disk is transported to the first film-depositing chamber 12a in accordance with the processing steps mentioned above.
The second film-depositing process part 20 has the same structure as that of the first film-depositing process part 10 except that the second film-depositing process part 20 does not have a load lock chamber. The second film-depositing process part 20 has a structure in which four film-depositing chambers 22a to 22d and three cooling chambers 23a to 23c are arranged alternately along the circumference of a predetermined radius r2 centered approximately at the central portion of the second chamber 21 formed in the circular swelled portion, and a second delivering position 32 of the connecting part 30 is disposed at the cooling position between the first film-depositing chamber 22a and the fourth film-depositing chamber 22d. A rotary carrying table 25 (
Evacuation of the chamber is carried out by an external exhaust pump (not shown) connected to the exhausting passage formed in the rotating shaft (not shown) of the rotary carrying table in cooperation with the exhaust system of the first film-depositing process part.
The connecting part 30 connects the vacuum spaces of both chambers 11 and 21 in common by the connecting space of chamber surrounded by a chamber wall 33 continuing from the first chamber 11 and the second chamber 21. The connecting part 30 is provided with the first delivering position 31 on the first film-depositing process part 10 side, the second delivering position 32 on the second film-depositing process part 20 side, and a delivering mechanism 34 (
Upon driving the pusher 171 located on the delivering position 31 of the first chamber 11 side, a disk substrate 501 with masks is adsorbed by the chuck 37A of the first rotary table 15 side. The pusher 172 on the second delivering position 32 of the second chamber 21 side is operated in the same time. A susceptor 26 of the second chamber side is then pushed up and a substrate 502 with masks is adsorbed by another electromagnetic chuck 37B. When both the substrates are adsorbed to the arm 36 side, both the pushers retract downward and respective susceptors return to the rotary table. Next, the arm 36 turns by 180 degrees and exchanges with each other the positions on which the substrates 501 and 502 are located respectively. The pushers 171 and 172 are again operated and push up each susceptor so as to come into contact with the disk substrates exchanged like the above. On the other hand, upon stopping operation of the electromagnetic chuck, respective disk substrates are placed on each susceptor. By repeating the operation mentioned above, exchange of substrates between both chambers can be continuously carried out in a vacuum with ease.
As mentioned above, the vacuum processing device of this embodiment has a structure in which the first film-depositing process part 10 constituted of four film-depositing chambers, two cooling chambers and one load lock chamber, and the second film-depositing process part 20 constituted of four film-depositing chambers and three cooling chambers, both the process parts being connected together through the connecting part as a common vacuum space.
By carrying out continuously multilayered film-depositing with two film-depositing process parts, the whole device can be made compact. If film-depositing positions or cooling positions in the continuous vacuum film-depositing using a rotary table are increased, the radius of the rotary table increases proportionally in compliance with the number of the positions, so that the volume of the chamber increases by about the second power thereof. In this embodiment, upon merely increasing the space of the connecting part a little, the vacuum space can be confined to the minimum, and exhausting efficiency can be ameliorated. Furthermore the diameter of the rotary carrying table becomes small and control of the driving motor can be easily executed. Quick intermittent rotation can be also realized.
In the case of fabricating optical disks having a multilayer film shown in
The multilayer film has seven layers and the first dielectric material film 202 is an insulating material such as ZnS—SiO2 and must be thicker than other layers, so that film-depositing is carried out by means of two film-depositing chambers for sharing the processes. Shared film-depositing can make the tact shorten.
Respective film-depositing process parts and the connecting part of the vacuum processing device are controlled together by the operation control part 60.
(1) The First Film-Depositing Process Part 10
1-1 The load lock mechanism 14—to transport a substrate of polycarbonate with a groove molded by a stamper machine into the load lock chamber 14a after attaching a mask thereto.
1-2 The first film-depositing chamber (1) 12a—to form a part of the first dielectric material film by sputtering on the transported substrate.
1-3 The cooling chamber 13a—to cool the substrate taken out from the first film-depositing chamber (1).
1-4 The first film-depositing chamber (2) 12b—to form the remaining part of the first dielectric material film by sputtering on the transported substrate.
1-5 To transport the substrate having the first dielectric material film layer deposited thereon to the first delivering position.
1-6 To transport a multilayer substrate having the second dielectric material film layer deposited thereon in the second film-depositing chamber (4) to the first film-depositing chamber (3) at the first delivering position.
1-7 The first film-depositing chamber (3) 12c—to form a thermal buffer layer on the transported substrate by sputtering.
1-8 The cooling chamber 13b—to cool the substrate taken out from the first film-depositing chamber (3).
1-9 The first film-depositing chamber (4) 12d—to form a metallic reflection layer on the transported substrate by sputtering.
1-10 To carry the substrate taken out from the first film-depositing chamber (4) to the load lock chamber 14a.
1-11 To take out the substrate having a multilayer film-deposited thereon from the load lock chamber 14a.
(2) The Connecting Part 30
2-1 To transfer the substrate transported to the first delivering position 31 onto the second delivering position 32.
2-2 To transfer simultaneously the substrate transported to the second delivering position 32 onto the first delivering position 31.
(3) The Second Film-Depositing Process Part 20
3-1 To transport the substrate carried in the second delivering position to the second film-depositing chamber (1).
3-2 The second film-depositing chamber (1) 22a—to form a first interfacial layer on the transported substrate by sputtering.
3-3 The cooling chamber 23a—to cool the substrate taken out from the second film-depositing chamber (1).
3-4 The second film-depositing chamber (2) 22b—to form a recording layer on the transported substrate by sputtering.
3-5 The cooling chamber 23b—to cool the substrate taken out from the second film-depositing chamber (2).
3-6 The second film-depositing chamber (3) 22c—to form a second interfacial layer on the transported substrate by sputtering.
3-7 The cooling chamber 23c—to cool the substrate taken out from the second film-depositing chamber (3).
3-8 The second film-depositing chamber (4) 22d—to form a second dielectric material film layer on the transported substrate by sputtering.
3-9 To transport the film-deposited substrate to the second delivering position.
In the fabrication process of a disk substrate, the steps from 1-6 to 1-11 of the first film-depositing process part 10 correspond to the after process of the process steps of the second film-depositing process part 20.
In this embodiment, the rotating direction of the rotary table of the first film-depositing process part is the same as the rotating direction of the rotary table of the second film-depositing process part. However the rotating directions above are free from each other for each film-depositing process part, so that they can be set in accordance with the processed object. In addition, operation of each susceptor can also be controlled individually in order to carry out necessary processing.
Because many steps such as combination of film-depositing chambers and cooling chambers can be installed in a downsized device in accordance with the present invention, multilayer film substrates to be processed by the sheet-fed system can be processed on variety of conditions. Therefore, evenness of the film thickness and uniformity of the film quality are improved, and thereby substrates of multilayer film with high quality can be obtained.
Besides, the structure of this embodiment can cope with variety of changes of the fabrication process.
With respect to fabrication of multilayer films constituted of four layers CD-R shown in
As mentioned above, the process can be flexibly changed in compliance with the type of the optical disk, and fabrication can be performed without useless film-depositing chambers.
As shown in
As shown in
As shown in
As shown in
In the horizontal rotary table system in which the rotary carrying tables of respective film-depositing process parts have rotating shafts in the vertical direction, a processed substrate to be loaded on each susceptor is carried on the condition of top-loading. Inconsequence, the electromagnetic chucks fitted on each arm of the pick-and-place-arm 72 are attached downward. The processed object having arrived at each delivering position or the load lock chamber is fixed to the top side of the susceptor on the condition of being hung in compliance with vertical movement of the arm, and is delivered to another position upon turning the arm by 120 degrees. The load lock chamber 71 opens in the bottom direction of the chamber and a substrate to be processed is carried in or out from the bottom side. When the pick-and-place-arm 72 is turned in the direction of the arrow of the figure, the film-depositing process starts from the second film-depositing process part 20 and the last-half film-depositing process is carried out in the first film-depositing process part 10 after passing through the connecting part. The substrate, on which the film has been deposited, is again carried to the first delivering position 31, and then moved to the load lock chamber 71 so as to be carried outside. Rotating direction can be arbitrarily selected a teach film-depositing process part and the connecting mechanism.
Because the load lock mechanism is disposed between the first and the second film-depositing process parts in this embodiment, independency of the film-depositing process part can be raised and the process step corresponding to the type of optical disks can be easily changed.
In this embodiment as shown in
Though the present invention has been explained heretofore using the embodiments mentioned above, it is needless to say that the present invention is not restricted to the embodiments mentioned above and many kinds of variations are possible unless they deviate from the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-146770 | May 2004 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP05/08882 | 5/16/2005 | WO | 11/17/2006 |
